Homemade Vacuum Table CNC

[woodzy]

Well, the vacuum table is complete – thanks for all your help or ideas. Here is some pictures of it in action.

First picture is an overview of the table – it has about 100 o-rings that can be used to hold done the plastic. I engraved each one so I once I know what I want to cut, I know which ones to remove the pipe plug and install an o-ring.



What I found out is to only cut the Corian within about .025 from breaking through. Place the corian on top of the table – center it based on the o-rings design.



I cut this using about 6000 rpms and 60 inches a minutes with a ½” carbide cutter taking two cuts each about .230 deep and leaving about 020 on the side. Once it was roughed, took a final pass to clean up the sides. It took about 5 minutes to cut the piece. Once cut, vacuum off the table with the shop vac – give it a quick shot of air to remove all smaller pieces.



I then broke out the leftover stock in the handle area and then put on the router table to round over all the edges. My guess is less than 10 minutes the cutting board is complete.



The only problem I have had is trying to get the suction to start on a large piece of Corian. I needed to place a board across the piece and then pry it a little against the head to start to compress the o-rings. Once they grab – it not going to move. I have a vacuum gage on order because I would like to see how much of a vacuum my pump is pulling. I’m thinking about anodizing the plate some color so I can see which plug is in the center or not. I changes the pattern and it took about 5 minutes to see that I didn’t put the plug back in on one of the holes that was out in the open. Maybe I should just paint the plugs.

Hope this give you an idea on how to build a vacuum table – you can make it as big or small as you like.

Jeff

[LeeWay]

That looks great. I may need to try something like that one of these days.
As for getting the suction to start, throw a sheet of thin plastic or a trash bag over it. That should suck it right on down.
It did with my first venture into using vacuum. My issue was my vacuum pump just wasn't strong enough.

[Trent Steel]

Wow, good work. Great design with the o-rings and plugs. I'll have to make something like that some day.

[j_wizard]

Can you give more detail on the Vacuum table build?
O-Rings used and size?

[woodzy]

Links have been corrected...

Here is some of the design considerations:
http://bbs.homeshopmachinist.net/sho...highlight=pump

Here is info on the pump:
http://bbs.homeshopmachinist.net/sho...highlight=pump

O-rings were #224, which are 2.00 OD, 1.750 ID, and .125 Thick. They were just the cheapest o-rings you can buy, I think it was $10.xx for 100 from McMaster Carr. They were machined .104 deep in the plate with proper clearance on both sides of the o-ring. Center section was a pipe plug with an o-ring for sealing.

[Geof]

Originally Posted by woodzy .....The only problem I have had is trying to get the suction to start on a large piece of Corian. I needed to place a board across the piece and then pry it a little against the head to start to compress the o-rings. Once they grab – it not going to move....Jeff

That is a nice looking job.

To get the initial grab for a large piece of material you could try installing a vacuum reservoir and a ball valve between the reservoir and the table. This way you can pump the reservoir down and when you turn on the vaccuum to the table you get a large suck that helps snap the material down against the O-rings and give the final tight seal.

[Dropout]

Originally Posted by woodzy Here is some of the design considerations: http://bbs.homeshopmachinist.net/sho...highlight=pump Here is info on the pump: http://bbs.homeshopmachinist.net/sho...highlight=pump O-rings were #224, which are 2.00 OD, 1.750 ID, and .125 Thick. They were just the cheapest o-rings you can buy, I think it was $10.xx for 100 from McMaster Carr. They were machined .104 deep in the plate with proper clearance on both sides of the o-ring. Center section was a pipe plug with an o-ring for sealing.

The links don't work...

[j_wizard]

Thank You.
Please keep us posted.
A design like yours is what I was thinking in my head.
I though that O-Rings might be to firm, and was looking for a very soft O-Ring.
I currently have a test setup with 3" very soft gaskets but they rebound into the cutter, I am tring to hold down and cut with out a spoil board. 3" is to large for my projects.

[woodzy]

Links above have been corrected - Sorry for the confusion.

[diycnc]

could you not use thicker o rings that allow the part to be held off the jig so you can cut thru?

[woodzy]

diycnc,

You are correct but if you don't cut through you can leave more o-rings in areas that would cut throught and you would loose suction.

Right now, the part is held off the table about .005 on top of the o-ring so that is an option if I want it.

[j_wizard]

What are you using for the plugs in the Vacuum table (Pipe plugs)?
They don't look like a threaded pipe plug. I assume that they just drop in the vacuum hole and are sealed by a smaller o-ring.

I do like this design.
Before I make a table like this I would like to know if there are any additional tips or changes that you may suggest?