Just Got My Stinger I

[Art Mann]

After waiting a couple of days for the roads to clear from the snow storm, I picked up my Stinger I in Cartersville last Friday. Yesterday (Saturday), I moved the Stinger to its permanent home, set up the computer equipment, installed a spoil board on top of the base, wrote a Vcarve program to mill the spoil board and successfully milled it flat and smooth. This afternoon, I am going to attempt my first real project, which is a small V-carved sign.

Things were a little busy at Camaster because they were teaching a two day class on software and hardware. In spite of that, Master Technician Luke Bennett took out about 45 minutes from teaching to give me a detailed introduction to the machine and Wincnc controller software. That little private class was as good as gold. I had already downloaded and experimented with demo versions of the software and was confused on several points. Luke cleared all that up in a hurry. He is a great teacher and really knows how to explain things clearly and quickly. I am so thankful that he took the time to help me out. I also appreciate Gary Campbell arranging for us to get together. Their reputation for strong customer service is well deserved.

There was one piece of information Luke mentioned that I forgot about until it was too late. We were talking about dust collection and he suggested I should have it in place prior to milling the spoil board. Well I didn't. I thought I would just hold the vacuum hose up next to the bit (2" dia. surfacing bit) and that would be good enough. Wrong! Machining 0.050" off the surface of a 2 X 3 foot piece of MDF in one pass puts out an incredible amount of dust. It resulted in a deep layer of dust deposited over a 10 foot diameter circle around the machine. I quickly gave up on the vac hose and just went outside until the program completed. Today I get to find out how effective my new little Oneida Dust Deputy cyclone separator is at preventing fine dust clogging a shop vac filter.

[Bruce Page]

Congrats on your new machine. Do you plan on using the shop vac as your primary DC? I went that route with my Fein T3 because I didn’t want to listen to my DC running for hours at a time. It didn’t take long to realize that the vac didn’t have enough Wheaties to do the job effectively.

[Art Mann]

Well Bruce, I am glad you brought that up. I have a few dust collection options in mind. I was thinking about buying a new top notch shop vac like the Fein. The dust collection foot that came with the Stinger has a 2 1/2 inch dust port connection that matches the size of a shop vac hose. I am kind of disappointed to hear that solution is not adequate. I also have a Delta 50-760 dust collector I could use. It has a 1 1/2 hp motor, 1000+ CFM (advertised) capacity and has the 1 micron felt and plastic bag configuration. If I use it, I will have to either modify or replace the OEM dust foot to accommodate a 4 inch flex pipe. I was planning on using the Stinger to cut out a Thien baffle separator for it and replace the felt bag with a Wynn cartridge filter regardless of where I use it.

I would sure like to hear from you and others as to how they provided dust collection to their small CNC routers.

[Bruce Page]

You might have better luck than I did so certainly give your shop vac a try. I’m using a Delta 50-850 DC. I retired the Camaster boot and bought the Kent dust boot that accepts a 4” hose. If you search camheads for What a difference 1200 CFM makes! you’ll see some pics of my setup.

[Art Mann]

Hey Bruce, I just checked out the pictures and that is a pretty innovative design. I will try the shop vac today since that is all I have that I can conveniently hook up to at the moment. I can say this. There is no way a shop vac would have handled the amount of dust coming off that surfacing bit when I milled my spoil board flat. I don't think even a 4 inch dust collection system sucking 700 cfm would have done a very good job the way I did it. The run time was less than a minute and i bet I generated a gallon or more of dust in that time. I am going to go slower next time just so the dust collection system can keep up.

[Keith Outten]

Art,

I found a 2.5" to 4" horn shaped adapter at either Lowe's or WoodCraft For my Stinger II. I also removed the baffle under the dust foot. Sorry, the attached picture was taken before I found the horn adapter.

Because CNC Routers are often used for long runs a shop vac is not the best choice because most are not designed to run for long periods of time. If you search you will find pictures of some shop vacs that caught on fire.

Art, the next time I replace my spoil board I'm going to use 3/4" thick PVC sheet instead of MDF.

[Art Mann]

Hello Keith,

I think I still have an adapter that goes from 2 1/2 to 4 inch dust collector hose, although it is a step shaped thing rather than a cone. When I tried it on my table saw, the air flow was restricted to the point that my shop vac actually provided better suction. I could try it again easily enough. I have a pretty good shop vac I was planning to try. If it works well enough I might buy a new and more powerful shop vac. I thought about buying a Ridgid brand because they have a lifetime warranty. That would address the issue of wearing out but it wouldn't address the issue of fire. I'm glad you mentioned it.

I am looking for an alternative to MDF. I hate working with the stuff but I haven't found a better material for some applications. Can you please post a link or provide a brand name of the PVC you are using? I would like to do some research on that subject.

While I have your attention, I would like to ask another question I'm sure you and perhaps others will have an answer to. Several months ago, I bought a sheet of 1/2" Corian really cheap ($50). Since then, I have fabricated a router table top using a piece of that laminated to a 1" thick piece of MDF. I haven't yet cut the hole for the router plate because I have been waiting to do it on my new CNC router. I am planning to use a 3/8" two flute spiral upcut bit. Is that appropriate? What kind of feed rate and cut depth should I use considering I have the Porter Cable 890 model router? I will be cutting all the way through the Corian and MDF.

Thanks, Keith and everyone else for all the very helpful information.

[Keith Outten]

Art,

My 4" by 2.5" DC hose adapter is a cone that is probably 14" long. I installed it as a temporary fix until I can remove the 2.5" connection and use 4" all the way to the boot. After more then 3 years I still have not found the time to modify my DC setup but I'm thinking seriously about getting the Kent dust boot that Bruce is using. Its a bit pricy but I don't have the time to make my own.

I strongly suggest that you Do Not Consider Using A Shop Vac for your CNC Router. The last thread I read on the subject was from someone whose garage caught on fire and he almost lost his home as well. In the beginning you think that your machine times will be short, that is rarely the case and a shop vac is just not designed to run for long periods of time based on all of the information I have seen on the subject. I think I remember Jim McGrew posting a picture of a shop vac that was under his router table and when it caught fire it caught the router table on fire as well. My memory isn't clear on who or what but I can tell you that there are a lot of people who will recommend that you use a dust collector.

MDF is NASTY!!! I used an MDF spoil board on my ShopBot and my Stinger as well but I'm done with MDF. In fact I don't ever want the stuff in my shop ever again. There must be a dozen brands of PVC. I have purchased AZEK and Celtec and can't tell the difference.....its all the same to me. My shop is full of the stuff these days and one of my storage buildings has PVC drops piled up almost to the ceiling. Most of what I have is 3/4" thick but I have a stack of 1/4" thick PVC sheets as well. Recently I placed a piece of 3/4" thick PVC on top of my Stinger's MDF spoil board and screwed it down to give it a try for awhile.

I use a 1/4" diameter spiral bit to cut 1/2" Corian in three passes at 1300 RPM. I can't remember the feed rate but I can look on my shop computer and get it for you. I don't normally commit these numbers to memory, between the CNC Router and my Laser Engraver there are way to many parameters to memorize for the various materials I use on an almost daily basis. The feed rate for every material type varies depending on the bit and the type of cut being made. My Stinger II has the old motors which don't have the power the new machines have so I tend to stay with 1/4" bits for cutting through Corian as it puts less stress on the XY motors. I use 3/8" and 1/2" diameter bits for various cuts but not for cutting through Corian unless I have to.

Concerning your router table top I would have recommended that you cut and glued Corian strips under the top, like a torsion box, rather than use MDF. You can epoxy Corian to Corian joints and they will be vary strong. Another option would have been to make a plywood torsion box frame and use silicone glue to adhere the Corian top to the support frame.

The picture below is a PVC slider I recently made for my band saw. I built a PVC box for my miniature metal lathe and I have been making VCarved signs from PVC lately.

[Biff Phillips]

I use 3/4" exterior plywood for my spoilboard. Works great, plywood holds screws better too, and no MDF dust to deal with.

[Art Mann]

Hey Keith,

Thanks for all the good advice. The more I work with the dust foot that came with the Stinger, the more I am convinced I need some other solution. The mount isn't very easy to adjust and the brush bristles are way to short for deep cuts. I really want to go with a 4 inch hose. Just out of curiosity, I emailed Ridgid technical support and asked them whether their most powerful shop vac was rated for continuous duty. They replied right away. They didn't say not to run it continuously but they did say not to leave it running unattended. I appreciate their honesty.

I did a little reading on Azek but I didn't find a local source of sheet material. I did find some trim planks at Lowes that were 1" X 8" X 8'. Is that the same stuff? If it is then I may go buy a board to experiment with. Can you machine a spoil board flat that is made of PVC?

I did some experimenting with Corian. I cut it with a 1/2" straight bit because that is all I had that would cut 1-1/2" deep for the router table. I used 13,000 RPM, 60 IPM and 1/8" cut depth. I was surprised at how well the machine cut the material. I believe I could have cut a good bit faster or deeper. Unfortunately, when I started cutting the hole in the table top for the router plate, it cut the hole rotated 90 degrees off from what the simulation showed in Vcarve. I think I misused the rotate function and the program didn't show the result like I expected.

Edit: About the router table top - I am using a Kreg router plate that requires a solid hole be cut all the way through from top to bottom (no shoulder) and it requires at least an inch of solid material to run screws into from the bottom that hold the support brackets in place. The top I am using now is a torsion box with the router base mounted directly to the under side of the top skin (1/2" baltic birch). It has been a very good flat and rigid top but it doesn't allow for interchangeable rings. That is the main reason I am building a new top. I think I am going back to 1-1/2" MDF laminated on both sides because I found the Corian to be almost as messy and more difficult to handle and cut than MDF.

[Keith Outten]

Art,

The PVC trim boards at Lowe's are probably the same material that Azek sells, honestly I can't tell the difference between brands of PVC. PVC machines like butter, you can machine it flat which is why I am experimenting with it now for my spoil board. I don't know of anyone else who has used it yet but I expect I'm not the first. You are probably going to have to look at commercial suppliers in your area for full sheets of PVC.

When routing Corian slow is the best way to go because your router bits will last a long time if you keep the speed rate down. Try a spiral bit and see if that works better.

For your router table top cut your full size Corian top and then glue a smaller piece under the top where you need the 1" thickness for the router mount. Cut Corian strips and glue them underneath the top where you need to add strength and rigidity, you'll have a great table that stays flat and smooth as glass. Clean Corian surfaces that are to be glued together with alcohol before you apply the adhesive.
.

[Sotos Patistas]

FWIW, I still use 3/4" MDF as my "base" spoil board, but I generally use 1/4" PVC sheet underneath the material I'm routing. One benefit other than the extended life of the MDF spoil board, is that I when making multiple passes to perform through cuts on thicker materials, I can often smell when the router has started the last pass as the routed PVC has a distinct odor. Also lets me know for sure that my bit has made it all the way through.