After reading all of @Tokoloshe topic on vacuum table build from last year I’m quite intrigued to make my own (so amazing that MDF allows air flowing through the board itself!) But having lost my job recently I can’t go and buy a proper vacuum device and whole setup for a lot of $$$, so…would a vacuum cleaner work?
@Fodder1 mentioned in a post that there are three types of motors and to have a “bypass” one is the best for a suction table…but do these exist on a vacuum cleaner? And what do my Swedish compatriots use?
A small shop vacuum works fine if you design around it. There’s really no need for so much vacuum that you’re getting a firm hold through mdf. Just build a sealed box with a bunch of 1/8 or 1/4 inch holes through the lid.
Generally speaking, central vacs and wet/dry vacs have bypass motors and normal household vacs do not.
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My first table was build around an old Miele vacuum. The problem with those is that, as Rocco said, their cooling is not great and they are prone to overheating, so I never ran it for too long. The suction was quite good though. It was also very loud, which led me to buy a sidechannel blower for around 250€, a vacuum pump was out of the question (it seems to be better for smaller parts as far as I know).
You can use a shopvac though. It is still loud, but it works. There are several good tutorials on Instructables and YouTube how to build one.
In hindsight I would say that I am not using it as much as I thought I would, because it really only works for sheet goods and as soon as you cut through, the holding power goes down quite a bit. I also have a MDF plate that is a bit bigger than the grid, so it sucks air out of the sides which is not really ideal.
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Is the sound of the vacuum not dwarfed compared to the sound of the CNC? Is it really an issue how loud the vac is? Just curious about it, my build will start in some weeks, so I can’t know myself (yet) 
Good to know. I’m trying to see if I can find some middle ground where in the top suction table I’m able to have isolated screw holes for switching between the two, clamps for the small projects and suction for the big ones 
It’s a different sound and depends on spindle speed. When I am cutting with 24k RPM the vacuum still adds a lot of noise, when running at 16k the vacuum is louder. 
I would not have thought that. I would have considered the CNC to be way louder. OK, I’m excited to see how it turns out once I switch mine on for the first time 
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Hi all,
Sorry I started a new job and play time has been very limited, so i missed this.
Ok, yes verything that has been said is true. But also if you are going to use a vacuum cleaner (as someone said an internal “drag behind you” vac is not equal to on of the motors i mentioned) as you hold down use hard plastic pipe to connect everything. You can get so many differnt fitting for the plastic pipe in somany different sizes you can make anything work.
The problem with soft hoses is that they basically take up some of your suction power. So by the plastic piipe and say the “screw together unions” you are eliminating any movement in the pipe etc.
A couple other things i gleened from the internet searching i did was that if you use a thin sealing liquid, ie varnish or paint or expoxy around the edges and the bottom, except around the port where the suction is and the port can be on the side with some work, then you loose no suction that way.
So if you were going to make a vac port the things i would watxh out for are
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At the start the vac strength is quite good, untill you start cutting through. — so people who use this leave an ‘onion skin’ so that they done loose that “seal”
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If you have several differnet size base plates is a good idea as you can use the one closest to you part
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This sort of work holding, at the vac cleaner sort of suction, is best for small parts
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The holding power reduces as more of the base black is exposed.
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Another way they do this is not to ise the porus nature of MDF and use a gasket around the outside of the block or sections of blocks. Then drill / mill a shallow pattern into the blcok.
As a general thing, and your milage may vary, even with my motors i dont use it for work holding.