Startup CNC with Ed ...

Ed was featured in ShopBot's ad in the December 2006 issue of Make Magazine.   If you're using your ShopBot for a unique application and would like to be featured in a future ShopBot ad, send your story to info@shopbottools.com.

Ed's Ugly One Hour Vacuum Source - February 2008

[Download pdf version of this article for printing]

In prior articles I wrote about my vacuum table and how I used the Fein Turbo III vacs to hold my parts. The Feins are quiet and ready to connect and run right out of the box. ShopBot can even provide you with them!

For those of you who want to get started using vacuum as a means to hold work on your machine, and want to either save some cash or build it yourself, there is another option for you to consider. Surf on over to http://www.lighthouseenterprises.us and let Ward fix you up with Imperial vacuum motors and mufflers. You will be looking at the heart of the vacuum systems, the motor. These are not going to be complete units ready to plug in, but the parts to assemble a wonderful vacuum source. You will have to wire up motors, drill holes and build a box. I will be showing you how I experimented with my motors from Lighthouse Enterprises. I am not suggesting that you should follow my example. Do look at the ShopBot Forum and see how others are using the same motors and just how fancy some have made the enclosures for their systems. The scope of my project was to get vacuum cheap and quick. I also wanted to build this vacuum source without using my ShopBot. The reason for this is simple, if I were just getting started, I would not have a vacuum source to hold parts down to cut this project in the first place! If this project sounds like something you want to tackle, then read on.

First I needed to mount the motors to something. I figured that drilling a hole the same size or larger than the inlet hole would be just fine. I used All Star spoilboard gasket between my motor and the box, but now Lighthouse Enterprises supplies a gasket with the motors. Since I didn't have a drawing of the vacuum motor flange handy, I took some scrap threaded rod and sharpened one end at the bench grinder. This rod will now be use as a long center punch. I put a washer and nut on the other end and positioned them so the rod would be suspended just a tad bit above the surface I was going to mount the motors on. This way the rod would hang straight and I could mark where the center of the mounting holes needed to be. Next I drew a circle around the base of the motors and found the center of that circle. This would later become the center of the motors inlet hole. None of the dimensions are critical! Let me quote Bill Young from his February 2007 article, "Unless you're cutting out valves for artificial hearts, don't feel like you need micro precision either."  This project is a good example of what he said. I will be using scraps to make this vacuum source!

I was going to get fancy and use T-nuts on the inside of the box for the threaded rod to screw into but decided that was going too far. I grabbed a hole saw that would cut a hold that I could just get my hand into to put a washer and nut on the rod inside of the box. I also put a washer and nut on the outside to lock the threaded rod in and prevent the nut inside from working lose. A dab of thread lock would be a good idea here as well. The next steps were very simple, I just built a box. No fancy joinery but I used plenty of glue and narrow crown staples to assemble the box. I found another hole-saw that will cut a hole almost the right size for the flexible vacuum hose I am going to use. A wrap or two of blue painter's tape on the hose makes the fit real tight. For those who are still making "heart valves", here are some dimensions of my box. They are sized like this because that is what I had in the scrap box. 33" long, 8.5" wide, 7" tall. I used a 4" hole saw to cut the holes for the motors to mount over. I think smaller holes would be better, but I had a 4" hole saw handy. The hose connection could have also been a PVC pipe or pipe flange with a short flexible coupling between the box and the ShopBot. At first I wired up an extension cord with the female end cut off as my power cord to test the system. Now I am using the ShopBot relay board to automatically control my vacuum motors and my dust collection! Next month I'll show you all about that!

Below are some pictures that will show you how I knocked together a quick, cheap but very effective vacuum source for my ShopBot. I have been using it for over a month now and am very happy with it.

The long black device pictured is the exhaust muffler that Lighthouse Enterprises can provide you with. The muffler will eliminate the high pitch scream from the exhaust port. The motor will still provide you with audible feedback so you will know if it is turned on or not. If you experiment with reducing the sound of the motor even more, remember to keep a good supply of air moving past the motor.

I think the following pictures will be self explanatory. Good luck with your vacuum source project.

 

Easy Signs in Five Steps - January 2008

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Since I am not a good painter, I look at this step of making a sign the biggest challenge. I have tried rollers, brushes and rags all with mixed results. I am going to explain this month how I can finish a sign quickly and get what I and others feel are fantastic results. You may already be doing something close to this so don't be surprised. Here we go.....

Step one- Route the sign in solid surface material.
Step two- clean the routed areas and let dry.
Step three- spray the routed areas and sides of lettering with the base coat
Step four- before the base coat dries, spray the top coat and let the two mix and mingle while drying.
Step five- After the paint dries sand off the over spray with your random orbital sander, polish and admire.

Now that you have the 5 easy steps, lets go a little deeper into each of them.

Step one: Routing the sign. My software of choice is PartWorks (Vectrics V-Carve PRO). I use a technique to get PartWorks to create two tool paths automatically. One for large area clears using a larger cutter and a smaller more detailed tool path with a smaller cutter. By doing this I reduce the time to cut a sign by much more than half. Here is how I do that. In the tool database create two “special” tools. I am going to use a 0.25” end mill and a 0.125” end mill. The trick here is to tell the software that you are going to V-carve the sign! When I enter the specs of the 0.25” end mill I select the tool type “engraving”. I tell the software to use a 0.1 degree angle and the diameter is 0.25 with a flat diameter of 0.249. Now create a special tool for the 0.125” end mill by entering values of 0.125 for the diameter, 0.1 for the side angle and 0.124 for the flat diameter. Remember to set your pass depth and the feed and spindle speeds appropriate to your work. Now all you have to do is select the vectors of your sign and tell PartWorks to V-carve it by using a large tool to create the area clear tool path and the smaller tool for the V-carving. My example assumes you are going to be using a 0.125” and 0.25” cutter. If you are going to use other sizes of cutter just enter them as engraving tools and adjust your numbers to fit your cutter.



Step two. I like to wash my solid surface with a mild detergent and lots of hot water before I paint it. This is to remove any dust that may still be sticking in the recesses. Make sure to let the sign blank dry before painting.

Step three and four. I use Rust-Oleum Hammered spray paint for this type of sign. I spray a heavy base coat of Dark Bronze followed up with Hammered Copper. You will have to adjust and experiment with how much copper spray paint you use. Don't try to get even coverage and you will get better results. I find that after I spray the copper on and it starts to dry I will give it a little more spraying in places to brighten up the copper. Not too much now; you are not trying to cover up the base coat of dark bronze.



Step five. After the thick paint has dried and gotten hard, I will start sanding the surface of the solid surface sign with 60-grit paper on my random orbital sander. Then I move up in the grits until I get to 400. Then I use buffing wheels to bring up the shine on the surface of the sign. The buffing starts out with one wheel and tripoli as the compound and then I move to the next wheel and white diamond compound.

There you have it, the five easy steps to making a very expensive sign. One thing for sure, if you are not making sawdust and spraying paint, you will not learn. Now go out and give it a try!


 

How I Zero the Z to the Bed - December 2007

I bet you are thinking... Why doesn't Ed just lay the Z zero plate on the bed before he puts the material to be cut on it?  It's quite simple you know!

When I change cutters in the middle of a job, I want to re-zero to the bed. I cannot do that with the bed covered with the job. So, here is how I solved that.

What you are looking at is a 1.5” diameter aluminum rod about 9” long. It is mounted to the end of my table and has a wire connected to the bottom and runs to the input #1 in the control box.

I copied the ShopBot supplied Z zero file to a Custom Cut file and changed the variable for the Z zero plate to a fixed number 0.00 since the top of the rod is the same height as the table of the machine. I also entered the fixed location of the X and Y that I needed the spindle to go to in order for it to be centered over the rod. Now all I have to do is run the Custom Cut file and the machine will move over the rod, run the Z zero routine and pull up to the safe z height. Nothing could be easier!

But wait! How do I get the surface of the rod exactly the same as the top of the table you ask? Well, here is how I took care of that. I created another Custom Cut file that will call the Custom Cut to zero the cutter to the aluminum rod. Then it will move away from the rod and prompt me to push the START button. Then it will surface 0.005” off the top of the rod. Next it changes the spindle speed by using the neat utility Ryan Patterson wrote. Be sure to look at the ShopBot Labs page to find the one for your spindle. http://www.shopbottools.com/shopbot_labs.htm. Then I surface my table with the same 0.005” depth as I surfaced the rod. Now both the table and the rod are at the same height. When I lay 4' X 8” material on my machine and cover the entire table, I can still zero the Z by using the “ZZR” (Z Zero Rod). Below are a few more pictures of the rod and how it is mounted. If you can make use of something like this, please improve on the idea and let us all know.

It's now time to get back to making those Christmas yard cut outs before it is too late!

Z you later,
Ed







 

My first Camp ShopBot/Ed's Vac Stack - November 2007

My First Camp ShopBot

Since my last article in July I hosted my first Camp ShopBot on September 8th. I had been to a couple of camps and one Jamboree before so I had an idea of what to expect, but no idea about all that goes on behind the scenes. Well, let me say that the folks from ShopBot will help you every step of the way. Bill Palumbo, Bill Young and Ryan Patterson showed up the day before and were ready to lend a hand doing anything that needed to be done. The rest of the ShopBot crew that came were here early on Saturday and pitched in to help me with any detail that was not completed. Jay Wyant, another ShopBot owner, spent Friday and Friday night cooking BBQ and all of the fixings for our lunch on Saturday. Of course, none of this could have been possible without the folks who showed up for the day. Some got up and spoke while others took pictures, video and soaked in all of the ideas and knowledge that flowed from person to person that day. Thank you all for doing your part in the camp. There are pictures on the Camp ShopBot Flickr site. One person who never gets brought into the “lime light” but who is there every step of the way is my wife, Melissa. Without her, I would have never been able to get to where I am now.

Ed's Vac Stack



As you may recall from prior articles, I use two Fein Turbo III vacs for my vacuum source. The Feins are working well for me with one exception: After a long run, the plastic canisters will start to soften and implode. This causes the top to deform, thus causing a vacuum leak between the motor and the canister. I decided to try out a small wooden box to replace the orange plastic trouble makers. So here is what I did.

I looked at the bottom of the motor and decided I was not going to suck water with this vacuum, so I didn't need the plastic cone that captures the float. The purpose of this float is to stop the vacuum from sucking liquid into the blower if you overfill the canister while picking up liquid. Four screws and that part was removed. Next I saw a small foam filter just below the opening in the blower itself. I pulled the foam filter out to discover that the plastic holder behind it was melted and deformed. When it does break, it will be sucked into the blower, and I don't think that will do it any good. So I removed the foam and the plastic disk behind it. Note: I am NOT suggesting you remove yours. You should have some filtration between your vacuum blower and the spoilboard. In my case the plastic part was deformed and I didn't want it to break off and the blower ingest it causing more trouble.

Now that I had the motor ready to mount to something, I built a quick box out of scrap wood. The ShopBot cut a nice hole in the top for the Fein motor to just sit on. I did add some gasket material where the edge of the motor will contact the top of the box. I did not used any hardware to hold the motor in place as gravity seems to be doing a Fein (pun intended) job.



Since I have two Feins, I built two boxes. One larger box would have worked just fine but I am using scraps and testing the setup. The only problem I encountered was the need to bend over to turn the unit on and off. They are sitting on the floor! A quick look around and I solved that by adding the vertical strips to the side of the bottom box and putting a cleat where the top box could sit.



Now I have a smaller footprint, two Fein vacuum sources and an on/off switch that is located at a good height. Now when I run the Feins for hours at a time, nothing implodes or leaks.

The next thing I need to add to the Vac Stack is a filter between the vacuum table and the motors to keep any debris out.


 

Making parts and fixtures without any CAD software - July 2007

You saw the round parts and jigs I was making in the last article.  All of them were made without the help of a CAD/CAM package.  I only used the keyboard and the ShopBot control software.  I am running 3.5.3 which is the current release as of today, and I find it quite an improvement over the release that shipped with my machine more than a year ago.  The team at ShopBot have sure kept the “thinking cap” on.  Now let’s get started.

I move the machine to the X and Y location that I want to be the center of the part.

When I type “CP” into the command box in the ShopBot control software I will get a Fill-In sheet.



“Diameter” is, of course, the diameter of the cut I wish to make.

The “Xcenter” and “Ycenter” boxes can be left blank and the tool will use the current position.  You could enter values here and the tool will move to that spot and then cut.

“Outside-inside-true.”  I will be using the outside because I am going to cut an 18.5” circle now.

“Direction” will be left at “default.”  I could have selected “CW” or “CCW” for a climb or conventional direction of cut.

“Begin Angle” I have left blank since I am cutting a circle and don’t care where it starts cutting from.

“End Angle" will also be left blank.  This will cause the machine to cut a circle.

"Plunge."  This command is worth making a note about.  This value tells the tool how much to go down on each pass.  Sounds easy, and it is, until you forget to make this value a negative number and you watch to tool go up on each pass.  It is hard to cut something if the tool goes farther away from the wood each time.

"Repetitions."  How many times do you want the tool to go around?  If I had the Z .25” above the surface of my material I wanted to cut, had the plunge value set to .25” and I wanted to cut through .5” material, I would need to go 3 repetitions.  The first one would go to the surface and the second one would go .25” into the material and the third would be .5” deep.  There is another way to do this and, that command is coming up shortly.  It is plunge from 0.

"Proportion X and Proportion Y."  I wanted the size to be what I had entered into the diameter box so I left this at “default.”  I could scale up my circle by entering values here.

"No Pull-Up."  This command made me think of my old HP 25 calculator that used RPN.  This catches me off guard so I always read it twice and think about it.  The box is asking you if you want to have the Z pull up after the cut is finished.  So, “No Pull-UP” should be “OFF” if you want it to pull up after the cut.

"Plunge from 0."  Here you can instruct the tool to go to the Z-zero position and then start your cut.  In my example, I used the current Z position of .25” above the material and just made three passes.  I could have set this option to “yes” and have done two repetitions with a -.25” plunge.  My example here will take into account material that is thicker or thinner than the exact .5” since it starts .25” above the surface.

"Special: Tabbing, Pocketing, & Spiral Plunge."  These are pretty cool features. I use the pocketing and spiral plunge with bottom ones the most.  When I cut wheels for my toys, I use the spiral plunge with bottom.  This causes the Z to go deeper as the tool moves around the circle. It does not just plunge and go around.  I find this puts less pushing force on the small parts and makes them easier to hold down.  Spindle owners will love this as they don’t want to plunge the spindle down hard and deep but rather ramp into the cut.

Now, in my opinion, we get to the most important commands of them all.  But you may say, "there are no more blanks in the fill-in sheet!"  And you would be correct.  No I am not crazy, but this did drive me crazy for a while.  Do you recall we never told the tool how fast to move or what size cutter you placed into the collet?  Try cutting an 18.5” disk and allowing the machine to think it has a .5” cutter in it, while you actually have a .25” cutter in it.  And try that at 10ips.  Look to the right side of the fill-in sheet.  There is a scroll bar.  Move it all the way down and you will see a couple of notes.



"Related Commands."  You had better go and look at these related commands because you will not get what you think you will without doing so.  And remember to do this each time you use this command or any of the others that are built in.  They all get the speed and cutter information from there.  I hope in some future release of the control software there will be either an indication of the bit and speed or maybe even a fill-in for the cutter and speed.

So by using the “CP” command to cut circles and pockets and the “CR” command to cut squares, I was able to make my jigs and fixtures as well as my parts and never open up Corel X3, Vcarve PRO or PartWizard.  I am not saying you don’t need a CAD/CAM package, because you do for some jobs.  They make life easy.  All I am saying is go and explore the power of the control software you have right in front of you.

Maybe at some future Jamboree there could be a contest centered around making something without using any software other than the control software and its built-in commands. Hmm, I might have to suggest that.

Ed
 

Vacuum is vacuum, but how you use it makes the difference - June 2007

I have had my PRTalpha96 for a little more than year now and am still learning how to do things and improving techniques I have been using for a while now. I would like to share with you how and why I have moved from a full table, four-zone vacuum system to a pretty simple vacuum system. As you might recall from one of my earlier articles, I was cutting full sheets of ply for another shop and had some trouble holding down some of the bowed pieces. I solved most of that problem by adding a second Fein Turbo III vacuum to double the volume of air that I could move, but I still had some sheets that needed screws to keep them from moving. Also you may recall that I make toys and other small parts. The full table vacuum system has not worked out perfectly for me with the very small parts I want to cut. With all of that said, here is how I have made the next step in my trek down the learning path of hold down:   I removed the plumbing from under my machine’s table, as well as the sheets of ply bolted to it. This left me with a machine without any bed at all, just the steel cross members. I laid a sheet of .75” ply on the machine and positioned it so I could move the tool past it in every direction.  Next it was bolted to the cross member exactly as shown in the ShopBot assembly manual. After this, I surfaced the table to remove most of the high spots and spread about a half gallon of Tightbond II over the surface. I placed another sheet of .75” ply on the glue-covered surface and installed two screws to keep both sheets registered. Next, lots of weight was placed on top. The next day after removing the weight and screws, I surfaced the table to be perfectly flat to the tool. A couple of coats of sanding sealer were applied and sanded after drying. Now I have a flat and glass-smooth table 1.5” thick.

In order to connect the vacuum to my table, I cut a hole through the 1.5” ply table that would allow the hose from the vacuum to fit tight from the bottom.

To use this type of vacuum setup I will need to create jigs or fixtures so I can focus the vacuum to the parts I am trying to hold.  Pictured here is an example of a small Brady Vac plenum created from Trupan.  This plenum was created by using the Brady Vac utility available as a download from the ShopBot Labs web page.

In addition, I make another type of fixture to hold parts that are either very small or difficult to hold with the Brady Vac system.  The advantage of this fixture is that all of the vacuum is directed to my part and I get no leaks around the edges or cutter kerf.

In the case of cutting many circles measuring 18.5” in diameter with a 1.35” hole in the center, I found the Brady Vac system worked very well until I ran across a sheet of .5” ply that had a very pronounced bow to it.

No matter how I tried, I could not get the vacuum to hold the part down on the Brady Vac plenum.  With the fixture made to hold only this circle, I was able to hold the same plywood tight and was able to finish cutting this job.

All of this further proved that there is no right or wrong way to hold your parts.  You will have to evaluate the types of jobs you run on your machine and decide what method works best for you.  I try real hard to not use any screws in any of my parts.  Others have used screws from day one and find it works just fine for them.  Don’t forget to consider the high-vacuum, low-volume pump that is used with pods or pucks.  Now that I have a nonporous table that is smooth, I will be able to use double-sided pucks to hold even smaller parts.  My shop sits about 550’ above sea level so I will get better results in my vacuum system than someone at a much higher elevation.

Be sure to watch for my next article as I will show you how I did all of the above cutting without opening any CAD or drawing software!  Everything was done from the ShopBot control software.

Ed

HSD Spindle Upgrade! - March 2007

Last month I said I was going to experiment more with V-bits and tell you what I have learned. Well, that project is still in the works and I hope to have information by next month.

The big excitement in the shop for February was upgrading my Porter Cable router to a 4HP HSD spindle. My reason for doing this was to lower the noise level in the shop, improve my cutting speed and increase my quality of cuts. Well I am happy to report the work to make this change was quick and painless. There were no unexpected things to fix or problems to work out. It was quite anti-climatic in fact. When I powered on the VFD for the first time and brought life into the new spindle, this grand event was heralded only by a quiet whisper of the cooling fan perched on top of the spindle. No bangs, whirrs, clunks, thuds or screams. Just peaceful quiet rotational bliss. I can now hear the song of the stepper motors as my machine munches its way through the day.

As well as installing the spindle, I also added four V rollers to my Z axis like the PRTalpha machines have. I thought this was going to be a real problem as the nuts need to be placed on bolts that are way down in the square tube that makes up the Z axis. This too turned out to be an easy task, as did getting all eight rollers to line up.

The VFD that ShopBot packages with the HSD spindles will only display frequency, not RPM. This is no big deal, and with a second or two in Excel, I had a nice chart to fix to the front of the VFD. Now I don’t even have to think twice about the frequency to RPM conversion. The conversion is easy, just take the displayed frequency and multiply it by the frequency of the commercial power in your shop. That’s 60 Hz for us U.S. folks and 50 Hz for some other parts of the world. In other words, if my VFD displays 150 for the frequency I would multiply that by 60 to get a spindle RPM of 9000. To find out what frequency to set the VFD to in order to get 11,000 RPM in my shop, I would take 11,000 and divide it by 60 and get a frequency of 183.3. My chart makes day to day setups real easy. If you do not have Excel or would rather not make a spreadsheet to print out, ShopBot has a nice chart in the back of the instruction book that you can fill in and put on the VFD. The VFD will display other parameters as well as frequency, and I find showing the current that the spindle is drawing is a good rule of thumb to indicate how dull a bit is getting. If you start a job and notice the current draw with a new bit and then check later after several sheets, you will find the current is going up. Unlike my router that would just run slower with the increase load, the VFD will increase current to keep the spindle running at your desired RPM.

I also requested 1/8”, 1/4”, 3/8” and 1/2” collets for the spindle as well as extra collet nuts. It is a snap to change collets in the nut but I chose to use the extra nuts to house the extra collets so I didn’t have to keep changing them out. Remember that you have to install or snap the collet into the nut before installing it in the spindle. Another trick I picked up from the Jamboree last year is the router bit shank needs to be flush or stick out a little past the inside end of the collet. In other words, make sure the surface of the collet that tightens up to the bit does so the full length. This will keep the collet from getting deformed and causing your bit to break. Now with that said, be sure the bit is not sticking through so far that it will bottom against the recess that the collet goes into. There should always be room between the end of the router bit and the end of the hole where the collet goes. I found the wrenches supplied to tighten and loosen the collet nut to be quite easy to use. It’s a funny looking spanner type of wrench and I find it much simpler to use than the wrenches for my Porter Cable 7518 router.

When you upgrade to a spindle, remember to warm it up before use after it has cooled down. The short time it takes to do this will extend the life of your spindle bearings.

I hope next time I can report on some software and some v carving.

Ed

Problems Solved - January 2007

Happy New Year!

I hope 2006 was a great year for you and 2007 will be even better.

The two Fein Turbo III vacuum system I wrote about in the last article got a good testing the week before Christmas.  The largest job I have run to date was completed on time and brought forward several inefficiencies in my shop.  In running this job I found that a lot of little things which had not been a source of irritation in the past became much more pronounced.  I’ll go over them and how I solved - or attempted to solve - them.

First, my shop is too small.  Since I will not be adding to it anytime soon, I have to find another way to overcome this.  I have read posts in the past on various forums about workflow, the triangle and dedicated machines.  How could I put all of this information to good use in my shop?  As you can see from the pictures below, I moved the ShopBot just a little so there was no longer a 90 degree angle between my sheet goods storage rack and the machine.

This helped me in pulling sheets from storage and loading them on the machine as well as taking parts off of the Shopbot.  This 45-degree shift effectively gave me three times the floor space at the end of the machine.

Second, it takes too long to cut a sheet of parts.  At first glance this might not seem like a problem if you are charging by the hour, but you only have so many hours in a day and deadlines have to be met.  This job required me to use a .25” bit as I didn’t have enough room to nest all of the parts and use a .375” bit like I wanted to so I felt I needed to slow the feed rate down.  This did not help the fact that I have a deadline to meet.  From past experience, I felt that I didn’t have the quantity of .25” cutters that I would need for this job, either.  Can you feel my stress building?  OK, here is what happened – I happened to find out about a tool manufacturer just 15 miles from me.  I thought that would solve the lack of cutters I had on hand.  One quick call and I learned that they only had three .25” up spiral cutters on the shelf.  They custom make cutters for shops, so they do not stock them.  I got the three cutters, and when the owner learned I was still new to CNC he moved into tutor mode.  I have to say, he didn’t tell me anything new from what I have been told at ShopBot, the Jamboree or any of the Camps.  For some reason, I just felt that slowing down the router and speeding up the ips was not the thing to do.  Do you see where this is going?  Lesson learned here is pay attention to the built-in chip load calculator in your ShopBot software.  It is there for a reason.  Use it!  I ran the router at 10K RPM and was cutting at 7 to 9 ips, and the machine, cutter and the wood loved it.  No more 3 ips and 20k for me.  The bit did not turn black, not even brown.  I didn’t break a single bit and only used two, not the 10 I expected to use.  Please use the chip load charts and experiment with feeds and speeds.  There are a lot of folks on the ShopBot Forum with answers as well as the folks at ShopBot.  Ask them where to start if you are having trouble.

Can I get better cut quality?  I am using that .25” up spiral bit I got just down the road and the bottom side of the Maple Ply is fantastic… the top is chipping out a little.  This is not the quality I want to send out.  As simple as this is to fix, in my state of panic to run the job on time, I missed something simple.  You have to remember, I do not have any special cutters on hand right now and the job has to be run.  I have up spirals and down spirals as well as straight cutters only and no time to order more.  I emailed Brady Watson and asked for his advice, smart move on my part here.  Brady answered and I could have smacked myself after reading his response….. use a down spiral to cut into the material and then an up spiral to finish it.  Let me tell you this, the cut quality on this Maple Ply is better than the factory edge.  Again, listen to folks and experiment.  I have to say that changing the bit for each sheet was not a problem and it went quickly.

I said that I would share how I solved or attempted to solve my problems above.  So far every problem was solved.  Here is the one I am still working on.  Power or torque.  My Porter Cable router 7518 is feeling the increased cut depth and speeds I am now cutting with.  It is working just fine and I am satisfied with performance.  I would like to not hear it bog down when I start a cut and wait for the electronic speed control to notice it is turning too slow and speed it up.  The noise from the router running at 10K to 13K is not bad.  Faster than that and it is quite loud.  My next option is a spindle.  Maybe I’ll be able to cut even faster with one.

The last bottleneck I encountered was trying to use the ShopBot control computer to do design work and run the machine.  Doing both is possible, but not at the same time.  Remember, I need to get this job run quickly.  I loaded my software on a second computer and was able to draw a sheet while one was cutting.  Easy to solve, if you have the second computer handy.

From all of this I have learned that not experimenting and finding the optimum feed, speed and cutter for a job before the job is due is not smart.  Not having a selection of bits on hand is not bright either.  Running the router too fast and the ips too slow burns up bits, breaks bits and doesn’t help anything.  Asking the folks at ShopBot or posting a question on the ShopBot Forum will give you access to the vast experience of the many users that frequent the board.  And best of all, I made the right choice in buying the machine that I did.

I have been experimenting with v-carving more than usual so next time I plan to share some of my blunders -er- learning experiences with you on why a 120-degree bit might be better than a 90-degree bit in some applications.  Maybe even a comment or two on a spindle vs a router, but don’t hold your breath on that one just yet.

One of the highlights for me last year was going to John & Doug Roughton's shop located in Kitty Hawk, NC for a wonderful Camp.  Thank you guys for a wonderful fun and education-filled weekend.  I look forward to this camp next year!!

Folks, if you have not been to a ShopBot Camp before, you are missing a big opportunity to learn from others and see how others are doing their work.  There is always something to be gained from sharing your ideas and methods with others.

Now go and make big sheets or boards into smaller ones and gain the experience to cut faster and better with less stress!

Ed

Holding Things Down - September 2006

I cannot believe I missed the entire month of August! That just goes to show you how busy the ShopBot has been this past month. Now let's get down to what was going on...

After the last article, I moved from using a high vacuum low volume pump to a single Fein Turbo III shop vacuum. This vacuum gave me a lot more cubic feet per minute of air flow but at the cost of much lower vacuum in inches of mercury. I was trying to spread this vacuum over the entire 4'x8' bed of my machine to boot. The lure of holding full sheets of 3/4" plywood was just too much for me to resist. I had to try it.

My first impressions were good, and the holding power was much more than I expected. I was cutting cabinet parts for another shop and the job would stay put till I turned off the vacuum. After cutting several jobs, I got the job that was going to burst my bubble, put me back at ground zero and cause everything to stop in the shop... Or at least I thought it would. I received a load of the most bowed ply I had ever seen. I had used Zebra Wood in the past, but never Rainbow Wood! Vacuum would not hold this twisted mess no matter how I pushed or pulled it. Screws was the only way to tame this beast. My bleeder board is still new and I didn't have a bunch of holes in it so driving that first screw was like getting that first scratch on your first brand new car. After getting the job out of the door and surviving the screw holes I started to think if only I had a little more CFM, I might be able to get that ply to suck down........

Next comes the second Fein Turbo III and a "T" installed in the manifold for both vacuums to connect to. I like the built-in feature on the Turbo III that will switch the vacuum on when a power tool that is plugged into it is turned on. With this feature, I connected the second Turbo III to the first one so I only had to switch one of them on and off. Works like a charm. Oh, I forgot to let you know that I tried a Sears Shopvac with the Turbo III before I bought the second one. In short, the Fein could produce more vacuum than the Sears so as hard as the Sears might try, the Fein caused the exhaust port on the Sears to suck air back into the system. In effect, the Sears was causing a big leak!

Now that I have all of this air flow, but no more vacuum as in inches of mercury I am ready to tackle that next load of Rainbow Ply. Well to date I have not gotten another sheet bowed like the others so I cannot comment on just how much better things are now with two Feins under the table. I can say that my cutting boards do hold a lot better. I am now laying the blanks directly on the spoilboard and cutting them right there. I learned the hard way that you must keep the debris cleaned from under the blanks or it will act just like small ball bearings and cause the blank to move around under the load of the bit.

After a quick visit to Bill Young's shop and seeing how he uses Baltic Birch to make a vacuum mask with gasketing, I had to try this for my setup. Let me tell you this, there has never been a happier ShopBotter anywhere than after I got my first mask with gasketing up and running! That is so slick and so easy to make, use and maintain. You have got to try it if you ever want to hold parts tight with a little vacuum. So you ask, how did I do this? I took a 49" by 60" 1/4" Baltic Birch panel and laid it on the bleeder board (spoilboard) I made sure the X and Y zero was exactly matched up with the corner, Lower Left on my machine. I then turned on the two Feins and that sucked the 1/4" ply down real tight. I then created a part file that would only cut into my 1/4" ply .0625" exactly where my outside profile cut would be for all my boards. Next I offset to the inside by .75" and cut the center out, all the way through. After this, I placed AllStar gasketing material just inside of the first profile cut but keeping it away from the center cut out. This way I was creating a vacuum chamber under most of my cutting board blank. I had a few blanks that were made from White Oak that had worm holes in them and a knot or two thrown off to the side. They would not suck down to the table and stay put. There were just too many air leaks in these blanks. With the vacuum mask and gasketing, these "dogs" stuck so tight I was able to cut them out at twice the speed I normally cut my boards and they didn't move. In short, if you don't like screws you will love 1/4" ply (or other materials) and gasketing coupled with a good vacuum cleaner for holding parts. I have never had the pleasure to use a Roots Regen Blower so I don't know how nice that might be, but for this little shop, two Fein Turbo III's and some AllStar Gasketing will take me far with holding my parts in place!

One other thing I want to say about my cut quality is that holding parts tight will make a big difference in the quality of the cut. The other is changing from a .25" bit to a .375" bit, WOW what a difference.

Last article I said I was trying out some new design software and I might say a thing or two about it this time, so here is a quick update. I am using V-Carve PRO ver. 3.1 for my design and toolpathing software. I find nothing better for me, in this price range for making signs and general parts. You owe it to yourself to at least look at this software package. I have also been using Corel X3 for more design work and exporting either an .eps or a .dxf file and importing that into V-Carve PRO. I already had the Corel package since that is the standard for laser engraver folks. Just today I designed a plaque in Corel, exported the vectors, cut the plaques on the Shopbot and then brought the plaque to the laser for engraving.

Till next month, here's wishing you parts held tight, sharp tooling and good business.

Ed

First Things First - June 2006

Some time ago I noticed the Shopbot ad in a magazine and thought that something like that would surely help out in doing the repetitive cutting of some toy parts. Thinking that CNC was way beyond my little shop, I turned the page and went on to the next article. As time marched on, the thought of CNC stayed, it would not go away. I decided to follow my dream and I have put CNC technology to work in my shop. I encourage my sons to follow their dreams as my parents encouraged me to follow mine. Following my dream of putting CNC technology in my small shop has been fun, exciting and not at as much of a cost as I initially thought it would be. I now have dreams of products that I could have not even have dreamed of before. Although CNC will allow me to cut perfect parts and many of them, this machine will never be able to create without me nor will be able to hand assemble, sand or finish. The Toymaker is alive and well, embracing new technology, knowing his place cannot be replaced with any machine, but using every machine to reach farther and go beyond limits of hand tools.

After the process of deciding which CNC machine would fit my shop demands and budget, Shopbot Tools was the winner. Without going into “sales pitch mode” let’s just say that the support and the business structure of Shopbot Tools, Inc. with the quality of the PRTAlpha96 won out.

Now that I had a machine on order, I needed to move my entire shop around to make room for the table as well as establish a new work flow in my shop. Little did I know at that time I would continue to refine the placement and flow in my shop for the next several months. A big advantage for me is I am full time employed and run the shop on a part time basis.

Initial Impressions

In late 2005, I made my pilgrimage to Durham, NC to receive my reward for waiting the required time between placing the order and having my new Alpha 96 ready to be transported to its new home. I left early that morning with my oldest son and arrived about an hour before I was expected. Based on my prior experiences with other companies, I expected to be pushed aside and told to come back later. Much to my surprise, we were welcomed, offered something to drink and a place to sit while someone checked to see if my equipment was ready for delivery. I was met again with a friendly smile and told that the X rails for my stand were being unloaded as we spoke and it would be a little while longer before my machine was ready to load. I said I would leave and come back later. I then got my next surprise, I was asked if either of us had any questions or if there was anything that could be explained to us while we waited! Did I die? Had I gone to Heaven? I was just not used to this level of customer service. In fact, my son and I had downloaded the trial software and had a bit of time to use the software before driving to the factory, so we did indeed have a question or two. We were having trouble creating a toolpath for one of the drawings that we had created. As it turned out, we had open vectors and just needed to close them. Tim took his time to explain all of this to my son who picked up on it quite quickly and then my son and Tim tried to explain this to me. I guess they both saw the deer in the headlights look I must have had as they both slowed down real slow so I could keep up with the explanation. Once I understood what we had done wrong and made sure we were ready to tackle the next phase of our CNC adventure, Tim introduced us to our next Shopbot Mentor, Norb.

We walked into the shipping area and took a look into an open wooden crate that was exactly like what our Alpha was sitting in. Norb explained how it was packed and what to do to unpack it and how to go about doing so. I didn’t realize just how important this was going to be to me just a few hours later. Norb then asked where my truck was and suggested a way to load the machine. This guy put the Alpha in my truck with the precision of a surgeon. Then after saying good-bye to folks and hearing, “if you need any help or have questions just call or email us”, we were off.

Upon arriving at home to our shop, my son and I knew exactly what to do in order to get the new Alpha out of the box without any trouble and started that task right away. We had the Alpha out of the box and all over the shop floor in no time flat! Then my son had to leave and go about his own affairs, leaving the old man to deal with the blue steel and wires without any assistance. After a little reading from the Shopbot Assembly manual I started bolting the beast together... Alone. Later that evening a cousin stopped by to see the new machine. It didn’t take any arm twisting to get him to stay and help with the assembly. In a short while everything was bolted together, leveled and squared to precision.

The next step was electrical. I decided a good night’s sleep was in order before starting this step. With sleep and a new day, the electrical section of the Shopbot Assembly manual was called upon to guide me through the final phases of bringing my new CNC machine online for the first time. Soon I was ready to connect the USB cable to my computer and bring this puppy to life. Can you remember the first time you drove without someone next to you? I expect it was quite exciting as you were trying out your new wings on your own. I also expect it was quite scary as you had no one to assist if something went wrong. I bet you did fine, and my first drive around the block with my new CNC tool was also successful. Thanks to the great folks at Shopbot, I now have new wings and just need to exercise them and to become familiar with what all this machine can do for me.

Learning the CNC Ropes

With the shop running well and the machine installed and cutting simple things, I am starting to learn just how much I do and do not know about CAD/CAM. With the Shopbot Camps around the country, I thought a trip to Ed Conley’s Camp in Marietta, GA would be a good place to start, indeed it was. If you have never been to a Shopbot Camp, you owe it to yourself and your knowledge base to attend the next one close to you. You will meet folks with much more knowledge than you as well as folks with your level of expertise, no matter what it might be. One of the first things you will learn is the family of Shopbot owners are a very wide and diverse group. Second they are helpful, going the extra mile to help you in every phase of getting your ideas to designs, your designs to toolpaths, your toolpaths to holding your parts and the final finishing of the created parts.

There is just so much knowledge to tap into. One thing common among all these levels was the willingness to share and listen to new ways of doing something as well as the exchange of ideas and products. Ed Conley fed us well and had a line-up of presenters that kept my left hand cramped from taking so many notes on everything that was said. Remember, I am new to all of this and this was my first Camp!

I also had the pleasure to meet face to face and shake the hands with people I only knew as screen names on the Shopbot Forum. It sure has made it nice to be able to put a personality to the writing of those active on the Forum. Ed Conley’s Camp was just the first door to open for me in getting my business off the ground and running.

The next stop for me was the Shopbot Jamboree held once a year in Durham, NC. Home of Shopbot Tools, Inc. The Jamboree is a larger Camp and is held at both Shopbot’s shop as well as the Hilton. There were many sessions on topics related to the business, design and the mechanics of getting the job processed and out the door. These sessions were designed to allow the novice user as well as the old salt to garner information and take it back to their shops to better the process of making their own items.

I was able to see folks I met at the earlier Camp in GA as well as the opportunity of meet folks that I only knew as names from the Internet. And, of course, I met many new people I didn’t know before the Jamboree. Another trip, well worth any Shopbot owner to take.

On my trip back home to Virginia from the Jamboree, I had a few hours to ride some less often traveled roads in North Carolina and Virginia. This gave me time to reflect on what I had just experienced at the Jamboree and make plans as to what I wanted to try next with my machine. This time, as well as with my first Camp Shopbot, I went with some expectations of what I might learn, but came away with much more. With the broader scope of what others are doing with their machines, again I have to remind myself to focus on a direction, stop changing my mind as to what I am going to make with this CNC machine.

What to Do If Your Full Time Job Keeps You from Working in the Shop

Let me say up front that I am not giving advice to you or anyone here. I am only relaying what works or does not work for me, in my shop, at this time. All subject to change... And probably will.

With a request for a cutting board from my wife, I decided to make it on the Shopbot. It would be a good project to get my feet wet in making something else. I decided to experiment with vacuum hold down on this job. Not having a fancy Roots blower but having a high vacuum low volume pump I use for the wood lathe, I decided to try making a “pod” or “puck” to hold my cutting board. As with most new processes, I had a couple of false starts, things that didn’t work and a hold up or two for parts that I wanted to try but didn’t have on the shelf.

After reading and posting on the Shopbot Forum, I was off and cutting my first cutting board. I had settled on making a small vacuum plenum from solid surface counter top material and using gasket material around it. On top, I would lay a piece of 1/8” Plexiglas and gasket the top, drill a hole in the middle and place my wooden blank on top of the jig.

After opening the valve to the vacuum pump the wood on top was held in place nicely and I was able to make my cut. Now that I have the solid surface material in place, I can simply change the Plexiglas mask to any shape I want and instantly I can cut another shape or part using the high vacuum setup. Over the next few days I cut many cutting boards and, quite frankly, seemed to have no trouble selling all I make.

So you ask, what does this cutting board and vacuum pump have to do with the title “What to Do If Your Full Time Job Keeps You from Working in the Shop”. For me it was to leave the full time job! That’s right, leave a nice 40 hour a week inside job that has benefits, paid vacation and retirement to work in a dusty shop lots more hours than 40 with no sick days or paid vacation time.

It has been a month now and more business is finding its way to my door each day. So for me, Shopbot was not the only reason I could leave the full time job, but it plays a big part in this becoming a reality. Thanks Shopbot!

Next month I will update you on how things are going in the shop as well as how my next generation vacuum table is working. I am also learning new software, so expect a comment or two on it as well.

Be safe in your shop! Ed