Securing wood to the CNC router

[bill z]

When you have your demos, don't forget to mention the vacuum hold down tables. Yes, they rob a bunch of Z space but, if built right, they can hold down a bunch. Sort of like air hockey table but sucking. Yes, you have to design it to have the vacuum holes where needed. The CNC can even do most of the work. I don't have one but I watch the YouTubes.

https://www.youtube.com/watch?v=B4HDGnJVe_o

https://www.youtube.com/watch?v=MR-WS8CUHrs

There is a good idea for a MDF table at the end of this video.

https://www.youtube.com/watch?v=TSTThLM8s8o

[cjablonski]

Agree with Bill, a vacuum table is the way to go eventually. Although I do not have one at home I have 2 where I work and the advantages are worth the time and investment. If properly designed it can be zoned to allow holding of small parts yet have area coverage for the largest projects. The limiting factor can be the cost. Vacuum pumps aren't cheap and the plumbing can add up. Additionally there are consumables (the MDF itself needs replacing eventually ). And at least the ones I've seen require some gasket to contain the vacuum itself. That said, it honestly is a fairly simple, fun and straightforward project you can tackle using your shark to create it. And in the long run, extremely worth it.

[Bob]

Bob, how did you get started with demoing units? Do you work for Rockler? It sounds fun.

I can see this being a common question. For me, securing down the material has always been the most difficult part of using the CNC machine once you have a design. It's not the same solution every time, either, which further complicates things.

Kayvon,
You are absolutely right. Doing demos at Rockler is a hoot!
How did I get started...I post a lot of my work on this forum. Corporate noticed that I was having fun. They asked if I would like to do demos at our local Rockler. It took me about 2 seconds to make the decision. I wound up doing demos and running our cnc group at the Rockler store. 34 members at our last meeting. That's a lot of people who are excited about all aspects of cnc in one room at the same time. Does your Rockler have a group? See about starting one if they don't.

Securing material, is a frequent source of discussion at our meetings. Also, lots of great solutions. CNC presents many opportunities, and challenges. It sure is fun.

Bob

[Bob]

When you have your demos, don't forget to mention the vacuum hold down tables. Yes, they rob a bunch of Z space but, if built right, they can hold down a bunch. Sort of like air hockey table but sucking. Yes, you have to design it to have the vacuum holes where needed. The CNC can even do most of the work. I don't have one but I watch the YouTubes.

https://www.youtube.com/watch?v=B4HDGnJVe_o

https://www.youtube.com/watch?v=MR-WS8CUHrs

There is a good idea for a MDF table at the end of this video.

https://www.youtube.com/watch?v=TSTThLM8s8o

Bill and CJ,
Those are good resources for information.
You're right, vacuum is a good source of discussion at meetings. Some of our members are fearless and try things that should not work...but do. For example, one uses a small vacuum cleaner to produce the vacuum. It works, and he has not burned out the vacuum yet. Several have tried vacuum tables on top of vacuum tables for versatility in setups. That works too. "Real" vacuum pumps are used, and HF pumps work.
If your Rockler store has a cnc group, help it grow. If there is no group, get one started. Some people work best when using forums like this one, some work best when attending group meetings. It's a unique experience to be with a group of people who are excited about sharing cnc at all levels.
Bob

[bill z]

I just ran across this use of masking tape and 2P-10 glue to hold down parts. NO DOUBLE SIDED TAPE! Really impressive.

Note the spoil board has been used several times already. Looks like the trick is to have a dust free spoil board and really press down the masking tape. Yes, the 2P-10 does it's magic.

https://www.youtube.com/watch?v=3uTsQ3dYRrk

[erich2027]

See the 2 attachments. I haven't cut the mounting bolts yet, but you get the idea. I cut the length to 25" so i can mount a full 24 inch work piece and I can still use a clamp on the spoil board. I used 1/2 inch MDF, but there is a tiny bow in the center, so I'm thinking about drilling two holes through the bottom of the CNC plate just small enough to screw 2 wood screws through to pull the MDF down to the metal plate. Also, you'll notice the lip toward the front of the table. That is square, so I can mount my work piece against it. I also have used double sided tape, and that seems to work great.

[gordread]

I saw a video on youtube where this guy puts down a strip of masking tape on the spoil board, and and a strip under the work piece, puts glue on one side, and glue activator on the other, and presses them together... The work piece doesn't move at all and when you're down, you just pry the board and tape up and simply remove the tape... I think i'll try that also.

This is my go-to technique for holding things down now. It works particularly well for small pieces or pieces where tabs aren't as practical, like gears for a clock. For large pieces, I'll still use tabs and clamps. Sometimes I'll use both, like last night when only three clamps would really fit on the work piece.

This is a new one for me. I think I will try it out. I would think normal painters tape would work? Or do you use an actual masking tape, with a little stronger 'stickiness'?

Gordon

[Kayvon]

I just use the blue tape, which I guess is painters tape. I've found it helps to lightly sand both spoilboard and workpiece with ~150 grit prior to taping (blowing off the sawdust first), but it works just fine even when I don't do that. I haven't yet tried it with cheaper super glue, but I'm sure it would work fine that way, too.

It's a little annoying to use up commodities just to secure a piece, but it's so much easier that I'm willing to pay the little extra just for the reduced hassle.

[csnyder3]

I also use a spoil board then use a good 2-sided tape between the spoil board and piece that is being machined. This has worked well for me.
Chris