[Frankmali17]

Hey hack, how is the machine working out for cutting plywood or melamine? what bits/ software do you use... and how well is it working out...
I'm actually hopping to build a machine using CNCRP parts like their pro kit...
If you had to do it over again, would you build or buy?.... what would you do different?

Thanks.
from a fellow woodworker/cabinetmaker

[Hack]

The machine is working pretty well. I have had a few issues but they have been operator / programming errors. I was having some issues with major backlash / out of round circles. Traced it back tot he fact that my z axis had loosened up. Tightened it back up and used some lock tite this time and seems to be fine. The Y and Z axis are smooth, the x not so much. Still trying to figure that one out.

For bits I use Amana brand mostly. Specifically the 46350 Solid Carbide Compression Spiral Bit. It does a great job on melamine and pretty good on plywood. They are about 45 bucks each. For software, I currently use Cut2D and Mach3, but working towards using Cabinet Parts Pro. I have also been looking at Mozaik, but not really wanting a monthly payment right now. Perhaps when I get the vacuum done and a few other things. Cash is tight for small business / startup and another payment is not wanted. Currently I use Alibre for design. Not the most efficient methods to get from design to machine, but it may be the cheapest.

If I were to do over again, I may look at some of the chinese 4 x 8 routers which are quicker to get up and running. I went with a buildable router because I could do it in phases and spread the purchases out over the several months it took to build. Hard for me to come up with a large lump sum purchase. I had designed a couple of routers on my own before settling on the CNCRP kit, but went with the proven kit instead of an unknown (my design). I do believe that the cnc router parts kit could be upgraded really easy if one wanted. The extrusion frame would allow the use of linear rails in the long run if one wanted.

Hope this helps

Dan

[bobmagnuson]

Hack, what's the latest on the vacuum table? Got it working?

[Hack]

Not quite. I had to order some flexible hose to make some connections. When I plumbed the table and the plenum, I did not do a very good job of aligning the 2 pipes up so that I could conenct everthing together. Word of advice to others. Start at one end or the other, not in separate sections to allow for an easier time of connecting and aligning things. The hose is due to arrive Monday.

I did get the motors under the table and everything wired this past week. Put a switch on the vacuums so they are easy to turn on / off. I wired them together on one switch. Might change this later depending on how things function. I still have to drill a 1/4" hole in the piping for leakage to allow cooling of the motors. This is per the website I bought them from. Unfortunately, I just noticed that I should have put a gasket on the motors as well, but didn't. Looks like I will be taking them back out and adding one. No big deal. (I should pay more attention) Also, I am still debating on whether or not I want to add vacuum guages to the 4 zones. I know I should, but I am feeling cheap right now.

Dan

[Hack]

Just ordered some vacuum guages off ebay. With having spent a few hundred bucks on motors, piping, etc another few bucks on gauges wont hurt.

Dan

[bobmagnuson]

Yeah, if you're going to all the trouble of doing it right, no point in not going all the way!

[Hack]

The hose and vacuum gages showed up earlier this week and I got everything connected this afternoon and tried it out. I set a 1/2 sheet of melamine on the table, opened 2 of the zones and tried moving the material around. Not good results. It moved as if there was no vacuum at all. I installed the vacuum gages and opened one of the zones. I get a reading of about 2 in/hg. Obviously not anywhere close to being enough, nor what was expected by me. I didn't have alot of time to troubleshoot as it was getting to be dinner time, but I did remove the vacuums out from under the table and hooked a gage up to it. I get about 7 in/hg with the 2" intake wide open and about 10" with it closed. This is pretty much what I expected for 2 motors in parallel. If nothing else, i know that the vacuum box is not the fault.

Basically, what that leaves is the flexible hose that I used to connect things, or the manifold design. Hopefully I will test things a bit further tomorrow. Basically I will just be placing a vacuum gage a different points in the system to see if I can tell where the majority of the loss is coming from. My guess, the flexible tubing even though it is designed for vacuum use according to the manufacture.

Dan

[tinygiants]

In a static system, vacuum will be the same at all locations as you are not maintaining the vacuum by flow. If you are loosing that much in vacuum, then I speculate you have a leak. The leak is either a poor seal between your table and the work piece, or it is in the plumbing. Can you pressurize any of the system? If so take some soapy water and spray over your joints and look for bubbles. If not, while the system is running, smoke the joints and watch the smoke to see if its flow is disrupted. Good Luck.

[tinygiants]

I just re-read the thread and reviewed your table set up. Are you using a gasket around the edge of your zones? I have seen other designs that will install a rope type gasket around the perimeter of the part if it is smaller than a zone, or around the zone itself to ensure a good seal against the part being held.

[bobmagnuson]

Dan, what's the latest on the vacuum table? Did you figure out where your vacuum loss was happening?

[Hack]

Well after having given up on this project, I took some time off from it, but a recent series of events has made me get back at trying to make a vacuum table for my router. What that series of events was is simply wrecking about 150 buck worth of bits in one week hitting hold down screws while cutting some parts. All user error, but still expensive nonetheless. This time it will be made simpler.

So first things first. I ripped the existing spoil board and table board off the machine and replace them with 2 layers of 3/4" MDF. This is in 3" x 49" wide strips and firmly attached to the table extrusions. From there I surfaced them so they are parallel to the machine.

From there I added a sheet of 3/4" mdf to be used as the plenum. On the bottom of the sheet I routed pockets and the bolt pattern to accept the vacuum motors. I am using the same motors I started this project with.

I then flipped the board over and screwed it down to the strips mentioned above. I layed out the screw pattern in my cad software to avoid hitting them later. Next, I routed the vacuum grid into the sheet. 1/2" wide by about 3/8" deep. The cut was a bit fuzzy so I took the time to run a small chamfer bit along the edges to clean them up. Probably not necessary, but visually better.

Upon completing the grid pattern, I took the board back off and secured the motors. Note the gasket material applied to the motors for a good seal before bolting them on. I did not do this on my last attempt and may have been a source of leakage / inefficiency.

Next was to put the plenum back on the machine and apply 2 coats of polyurethane to seal the grooves.

Enjoy the pics so far.

[mussersail]

I only have a few month old machine, but have been looking at possible vacuum table project and caught up on your posts from a few years ago it looks like. I too am using the machine a significant portion of the time for nested cabinet production. You were talking about software back in 2014 - what did you end up going with? I saw the Cabinet Parts Pro and it looked like a super deal, but couldn't really find much more information about post processors, or anyone actually using it. Because of this I went with Mozaik and have been busy getting used to this hardware. There are some features with Mozaik that have enabled me to process boards fairly trouble free without a vacuum, although, obviously the vacuum would be better. There is an option for tabbing, and more importantly, a tool path is created to make a final pass and remove the tabs. So far my experience as been good with plywood and MDF - compression bit keeps enough saw dust packed into grooves to keep pieces from shifting when last tab is cut. Melamine is just too slippery for this and I find myself dancing with the machine and manually holding each piece when last tab is cut. This has worked fine and since there are only 4 tabs per piece, it goes pretty fast. I also had to adjust the margin around the nested pieces to 3/4" - this allows me to use the plastic nails to shoot my piece to the spoil board. The nesting isn't as efficient so you might end up needing an extra sheet now and again. Plastic nails have been working great and no worries about tool damage.

[ger21]

Next was to put the plenum back on the machine and apply 2 coats of polyurethane to seal the grooves.

I'm not sure if two coats of polyurethane are enough. If you add another coat and it still soaks in, then it's not sealed.

[Jon.N.CNC]

Good work. Do you have any videos of it working? How is it at sucking through a spoil board?

[Kosh]

I'm not sure if two coats of polyurethane are enough. If you add another coat and it still soaks in, then it's not sealed.

Definitely NOT.

I used shellac to seal mine and just ripped it off and gave up when I realized I was losing 2/3 of my vacuum through leaks.

I could remake it better I guess, but the reality is I was wanting to hole SMALL parts with it, and that would work best with custom jigs. So I went back to a t-slot
spoil board for most cutting, and double backed carpet tape for inlays, etc.

@Hack, have you seen the nylon nail gun that CNCRP is selling?

[Hack]

"You were talking about software back in 2014 - what did you end up going with?".

I never did find a software package that I liked. To be fair, I never paid for any of the cabinet software out there and I am sure there are some good ones out there that could work, but I don't do enough to justify it. I believe CPP would be good for faceframe cabinets, but I was not able to get it to consistently do frameless cabinets the way I liked. I took the long way around and nest individual cabinets on either full or partial sheets - 1 cabinet per sheet (or partial sheet). I cost the entire sheet or partial sheet to the job. Once a cabinet is programmed, I never have to do it again. I can actually get quite good a nesting these. It also allows tweaking programs as needed for speed, gut quality, etc. Investment up front, saves time later. I just make a list of cabinet boxes that need made, pull each one up on the computer attached to the cnc and cut the cabinet. One benefit is that I have complete cabinets at that point and can build that one while waiting on the next. If nested across multiple sheets I could potentially wait for the machine to cut a few sheets to be done prior to being able to take the next step.

Good work. Do you have any videos of it working? How is it at sucking through a spoil board?

Not yet, still not quite finished with it. Should be done by the end of the weekend.


I'm not sure if two coats of polyurethane are enough. If you add another coat and it still soaks in, then it's not sealed.

I found that the 2 VERY heavy coats were fine for the grooves, but as I seal the edges of the mdf, it is taking more.

Thanks all.

Dan

[Jon.N.CNC]

"You were talking about software back in 2014 - what did you end up going with?".

I never did find a software package that I liked. To be fair, I never paid for any of the cabinet software out there and I am sure there are some good ones out there that could work, but I don't do enough to justify it. I believe CPP would be good for faceframe cabinets, but I was not able to get it to consistently do frameless cabinets the way I liked. I took the long way around and nest individual cabinets on either full or partial sheets - 1 cabinet per sheet (or partial sheet). I cost the entire sheet or partial sheet to the job. Once a cabinet is programmed, I never have to do it again. I can actually get quite good a nesting these. It also allows tweaking programs as needed for speed, gut quality, etc. Investment up front, saves time later. I just make a list of cabinet boxes that need made, pull each one up on the computer attached to the cnc and cut the cabinet. One benefit is that I have complete cabinets at that point and can build that one while waiting on the next. If nested across multiple sheets I could potentially wait for the machine to cut a few sheets to be done prior to being able to take the next step.

Good work. Do you have any videos of it working? How is it at sucking through a spoil board?

Not yet, still not quite finished with it. Should be done by the end of the weekend.


I'm not sure if two coats of polyurethane are enough. If you add another coat and it still soaks in, then it's not sealed.

I found that the 2 VERY heavy coats were fine for the grooves, but as I seal the edges of the mdf, it is taking more.

Thanks all.

Dan

Look forward to it. I am limited to single phase here and a rubbish amount of amps so this type solution is looking to be my only option. Am i right in thinking the current draw of these vacuum motors drops when there is less air passing through them?

[Hack]

Updates

Well to keep everyone updated, I made a bit more progress. First of all I put the spoil board on and turned the vacuum on to assess the hold down. Nothing, Zip, horrible. Oh great I thought. So, surface a few thousandths off the first side and flipped it over, glued it down and turned the vacuum on to help hold it down. The sheet had banana's a bit from being unbalanced at this point with a crown of about 1/4" in the middle. Once the vacuum was turned on it sucked it down quickly. At that point I new I had good vacuum, but it wasn't pulling through the mdf spoil board. I put a couple of smaller pcs of melamine on the table to see how the suction was now that 1 side had been surfaced and it was night a day different.

The pictures show an approx. 24 x 36 and 30 x 42 pc and I can't move them by had without prying on them quite hard. I actually took a small pry bar to break the seal. Very pleased. Now I need to surface the second side. I assume this will allow more vacuum to pass through. You can also see in the picture that I started to seal the edges as well, this should help as well. It will take more then the 2 coats originally thought to seal the edges.

I did try a small pc of melamine - approx. 10 x 18 - and it did not hold well. I will try it again after sealing the edges and surfacing the spoil board. I rarely use less than a 32 x 48 size pc to start with and I am pretty confident at this point that it will be good based on initial results.

The other picture is what happens to a 1.25" diameter bit when it hits a screw.....ouch. At least it didn't break like the 1/4" "expensive" ones did.

In hindsight, I may have given up on the first attempt to early. I never got to the point of surfacing the spoil board (on either side) and think this may have been where I was losing the vacuum. May never know but.....

Thanks for following along.

Dan

[Hack]

Am i right in thinking the current draw of these vacuum motors drops when there is less air passing through them?

I do not know that for sure. I have (2) 20 amp 110 circuits in the shop and run the router, computer, electronics and dust collection on one, the vacuum motors and lights on the other. If I sneeze, the breaker blows. It works, but less than ideal.

Dan

[Jon.N.CNC]

Am i right in thinking the current draw of these vacuum motors drops when there is less air passing through them?

I do not know that for sure. I have (2) 20 amp 110 circuits in the shop and run the router, computer, electronics and dust collection on one, the vacuum motors and lights on the other. If I sneeze, the breaker blows. It works, but less than ideal.

Dan

I've been searching for some figures on this effect however It's not returned any results. I'm pretty sure it is the case. One way to tell is switch them all on without spoil board and see if your lights flicker lol. Try it again with a spoil board and again with spoil board covered. No flicker then would suggest making sure you only switch on zones after they are covered. I have 30a total so with 6 motors that I'm planning I'm pretty much relying on there being a considerable drop. Will have to get a power consumption meter on my shop vac see if I can prove the theory.