Do CNC Vacuum Tables Really Work? UNEXPECTED RESULTS

[@dwwoodbuilds]

Great video! Covered the most common situations, covered the pros and most of the cons (maybe a follow up on the lifespan of the sheets and how to prolong). Allstar and airweights are making a mark in the small scale CNC business! and clean your shop!

[@HamiltonDilbeck]

Thanks! I did ask about how long the sheets "last" if they are not fully cut into and Allstar said they have customers that have been using the same tile gasket for over a year!

[@SebbyG86]

here is some tips from my experience of working on an industrial machine. If you really want to test the hold down strength, get some 18mm ply that's cupped and see how well the vacuum set up will hold it down and then try to machine it, especially cutting strait through. the more rigid the material, the more problems you encounter with vacuum tables. next, especially for scenarios like your example of cutting out 90 small parts covering the majority of your surface, use an up-down compression cutting bit, these force the sawdust to stay in the cut and well compacted to stop parts from being able to shift. 6-8mm diameter bits work really well, especially if your machine is strong enough to cut out the profile in 1 pass, overwise consider tabs for small parts even with a vacuum table. you are, in my opinion, 100% right that more smaller zones is better then fewer larger ones. the machine I used was 1 giant zone, and if it fails anywhere, it fails everywhere. multi zones like you suggest is far safer and less problematic and also more energy efficient. i also would say a cheaper option then buying those stick on sheets with holes is to just lacquer /paint the mdf you want to use as your sacrificial piece (you basically want to seal it) and then use your cnc to cut the holes, or even a different pattern. you'll prob get a better result doing this as you can also seal the sides of the mdf which will increase the vacuum as it will have less surface area for air to get sucked in from. one other piece of advice on the sacrificial piece of MDF. MDF usually arrives lacquered on both sides. when you machine the first side flat, its great as the vacuum table should form a fantastic seal against the bottom side, however once you flip it and start machining the second side, your vacuum (hold down strength) will drop. doing a zigzag pattern up the the mdf is not ideal, a snail shell pattern is better and depending on whether the mdf is cupped or bowed or anything start from inside or the outside. if the mdf lifts up on the outside as you loose suction and you profiled starting on the inside, then you will cut the mdf deeper on the outside and any following work you do will suffer from this consequence, I.E. leaving some onion skin behind as you experienced. so ideally in that instance you would have wanted to start your flattening profile from the outside in, maximising the vacuum strength at the start. Hope this makes sense. its hard to explain unless you have experienced this. The vacuum table i experienced was very old and underpowered in my opinion which aggravated all these problems, but if you encounter any of the above, these are good potential solutions.

[@stlwoodworking]

Nice. I also have the 2x4 and I love it. Airweights are awesome!

[@HamiltonDilbeck]

So great!

[@jamieclarke321]

You can make your own tile gasket on the CNC machine BTW, just use 1mm self adhesive foam and machine the 1/4 holes in with the CNC 👍

[@Hinkleshop]

Great job Hamilton! now I have to add another thing to my wish list

[@HamiltonDilbeck]

Christmas is right around the corner!

[@twomakerscrew]

Another great video, you answered all my questions!!

[@HamiltonDilbeck]

Thanks! Thats what I like to hear!

[@louisfbrooks]

I have had mine, 24x48, for a couple of weeks and really like it. The only issue I have was the fitting from the pump to the moisture trap was to short but that was an easy fix. The pump does put off a lot of heat though especially on long multi hours cuts. I need to figure out a way to exhaust it to the outside. I will be interested to see what you come up with on the mdf.

[@MattWeber]

I mean the test with foam in the shrinking island started moving wellll before you stopped it. The right side was basically floating at almost twice the size you show.

[@sparks-tech]

Clean your Shop!! Thanks for a great video. Lots of great info.

[@HamiltonDilbeck]

lol thanks!!

[@BadPandaWoodworks]

I bought a vac pump from a guy that was at 7,500' altitude. He thought there was something wrong with the pump. Got it super cheap... Got it home, plugged it in, and it pulled as expected for my 5,500'. Dude didn't know about the altitude drop off.

[@HamiltonDilbeck]

I hadn't thought of it either until I was talking with Airweights about potential failure points. the more you know!

[@BadPandaWoodworks]

@HamiltonDilbeck yeah. It's crazy how quickly you lose pressure. I drove from like 20' altitude in Georgia home to 5,500' in Colorado... Everything with a flip top lid popped open, and a bag of chips exploded. Which sounded like a damn bomb went off in the back of the car.

[@vanduraful]

I love the idea of one of these and with the foam and all parts you definitely answered two of my biggest questions. It’s just soooo much money. 💰 😢

[@HamiltonDilbeck]

Yeah vacuum work holding isn't cheap! But its still one of the cheaper options around!

[@vanduraful]

Oh I forgot to mention “great stuff foam cleaner” (yellow can sold by expanding foams at the big box stores) instantly dissolves any foam residue on your bits. Or anything else for that matter.

[@RoseKindred]

Using the foam was a good call. Sure, it could hold wood securely but foam has more play. The foam showed it off well. I remember the hanging vacuum test and was waiting for a follow-up. More specifically, after those fans I was waiting to see if you had an old kitchen sink to hang from it, cause, funny.

[@HamiltonDilbeck]

Haha yeah I was going to even make a chair this time and sit on it mounted to a wall- but I chickened out! Maybe next time

[@jamieclarke321]

Hmm the tile gasket looks more glossy than the foam I used. Is it more like a vinyl/ rubber material?

[@aaronblackford981]

I wonder if using tyvek type tape or just packing tape to help seal certain rows or columns to help it pull more from the area needed. I first was thinking covering the whole back but if your cutting a 1.5 “ row/column area with 1/8” between, then you could use 1.75 inch tape for instance so you have some fudging as long as it doesn’t overlap?

[@HamiltonDilbeck]

Airweights did mention that if you have material thats not fully grabbing- you can use packaging tape or some other type of slick tape and it will help a ton!

[@HarresMakerShop]

Clean your shop. Great video Hamilton.

[@HamiltonDilbeck]

FIRST! And thanks!

[@RBallarddesigns]

Slick table setup

[@HamiltonDilbeck]

Thanks, Ryan!

[@InspiredCraftsman]

Clean your shop. I built my vacuum table using vacuum motors from ametek, works great. I just use lightweight mdf for the bleeder/spoilboard and no longer use tabs. I almost always use compression bits cutting full depth in one pass. The sawdust packing behind the bit along with the vacuum allows me to cut very small parts.

[@HamiltonDilbeck]

GREAT POINT! I completely forgot to mention downcut bits and sawdust packing can help the part stay put. Thanks!

[@rexmundi8154]

Having used both, feel like a vacuum table is just trading some mild inconveniences for others. The blue painters tape and superglue trick takes a few min to set up, but it’s cheap and it holds great. The vacuum table is loud and expensive and you’re always fussing with it.

[@InspiredCraftsman]

@rexmundi8154 I still use painters tape and super glue for very small parts (less than an inch cutouts in very thin stock). The vacuum is great not worrying about hitting clamps or screws and multiple sheets of the same part are a breeze to change out by just flipping the switch. I have about $400 into my vacuum setup. Depends on what your needs. I had to use vacuum to improve part quality. It was mainly to hold sheets perfectly flat against the bed. A slight bow in the sheet gets pulled flat by the vacuum. I get little to no tool marks in pockets and much better results when v-carving.

[@rexmundi8154]

@@InspiredCraftsman I guess I was thinking about my own use case where I’m machining stuff in a CNC Mill like a Haas. I’m planning to get a onefinity when I retire. I agree about clamps. I almost never use them

[@InspiredCraftsman]

@rexmundi8154 I would love to have a cnc mill. I'm dabbling in the machining world with a victor lathe and a 3/4 size mill. For woodworking I'm running a shopbot cnc and do a lot of sheet goods, so that's where my perspective is coming from. I can't say enough good things about shopbot. My machine was built around 2010. shopbot was very helpful with tech support to get it up and running.

[@brandonbevan6426]

I’m surenot did you answer whether you can use the mdf or not if you flatten both sides?im considering buying the 2x4 option very expensive. Can you use that mdf as a gasket material instead of the mat or is the mat more for air loss?

[@HamiltonDilbeck]

So the mat is more for concentration. So its like using a straw to grab the part, rather than a larger area. Tons of little straws, I guess lol. I think the next mdf I'm going to try is gonna be 1/4" and I won't surface it. Time will tell!

[@bigeasy_f150]

i wonder how good your setup with the thin mdf and gasket would work on EVA foam like seadek

[@HamiltonDilbeck]

I bet it would work perfectly!

[@alexduffey]

ok you have pretty much set my mind that I will be upgrading to air-weights after my holiday market income comes in lol

[@HamiltonDilbeck]

They are super worth it!

[@fcschoenthal]

You mentioned acrylic works great on the table. What materials wouldn't work well? - Chris

[@HamiltonDilbeck]

Things that are rough. So any rough wood isn't going to hold! Using packing tape on rough wood, could help though

[@jonathanyost5546]

I wonder how the Tile Gasket product compares to just covering the exposed parts of the spoil board with melamine or rubber sheets. Has anyone seen that sort of comparison performed? edit: I should clarify that I'm talking more about holding down larger pieces. I'm also curious if TG works well with higher CFM vacuum table designs.

[@HamiltonDilbeck]

Tile Gasket was originally made 20 years ago for large format tables! Its for sure meant for big pieces. Not sure aobut melamine or rubber sheets- but I do know that the gasket material still will hold a seal when the top has been cut a bit. Its great!

[@Cadence_MFG]

CNC Ya Later double sided sticky tape!

[@HamiltonDilbeck]

Lol love it

[@D-GatDesignsLLC]

Can you post a link for the bottle opener inserts you use? I been looking for some and every set I buy end up being crap

[@HamiltonDilbeck]

Yep! Out of the office right now, but I'll post a link in the description tonight!

[@D-GatDesignsLLC]

Never got a reply about the bottle openers insert​@@HamiltonDilbeck

[@HamiltonDilbeck]

​@@D-GatDesignsLLC they are in the description of this video!

[@jameskuhlman9835]

They aren't mistakes, they are part of an iterative continuous improvement development cycle . OR If you aren't messing stuff up, you aren't pressing the boundaries or learning anything new.

[@HamiltonDilbeck]

I like that!

[@NeilBlanchard]

I am wondering another possible function for a vacuum table - and that is can it pull a warped sheet down flat? It doesn't appear like it could; based on your comments about having to press the foam down when it was warped? Or - with an 18mm thick sheet of Baltic birch, if you could press the warp down, would it then hold it flat?

[@HamiltonDilbeck]

I wouldn't count on it flattening a piece of baltic birch. Its great at holding, but I think the foam was much more pliable than plywood would be

[@NeilBlanchard]

@@HamiltonDilbeck - that's what I would think, too. I will continue to use edge clamps, and move them to allow access as the spindle moves from edge to edge of the panel.

[@SebbyG86]

depends on the vacuum pumps and how good of a seal you can get. i used to stand on our CNC to get 18mm ply to suck down (industrial machine sized 2440x1220mm). but in a perfect world youd put those really warped or cupped sheets to the side and cut them down smaller so you dont have to deal with it. The place i worked at didnt accept returning warped wood so we had to find solutions to get it to hold down. sometimes had to get masking tape out and tape the stock all around to form a good seal with the MDF. not a great solution as depending on how warped the stock is, as soon as you start cutting through and you loose suction strength, your stock can just pop off, or, in some occasions, especially if you tapped the stock to the MDF, the stock will lift off and pull the MDF with it clean off the vacuum table, and now you have the scenario where your CNC can move a full piece of 18mm ply 2400x1220mm around the table. Ideally if you do any of the above, your doing it on a project that doesnt require you to cut all the way through, or you leave an oversized onion skin.

[@NeilBlanchard]

@@SebbyG86 Right - the challenge is for me as a startup business (making mass loaded transmission line speakers) the ~$100/sheet price of 18mm Baltic birch has to work. I have been doing a series of edge clamps (of the panel that is cut to size already) and pausing the Journeyman Elite to move clamps as it progresses. Then the joints are cut flat, and can be clamped during assembly, and have things come out right. Vacuum hold down is not going to be practical for this.

[@SebbyG86]

@@NeilBlanchard we used to make speakers and subs, some subs so big it took 4 full sheets of 18mm to make 1. If you are cutting the sheets down to size first then machining them, i think your best bet for speed would be vacuum table + jigs. Jigs makes it so it redirects the vac to your piece your working on, and then you dont have to faf with the clamps. but obviously its an investment as you will have to make all the jigs, but once you have made them you would gain time. i couldnt fathom stopping a program to move clamps, over and over.

[@chrisc3170]

clean your shop

[@kennethritchie3138]

Clean your shop