# Hold it Down



## jetvich (Oct 19, 2007)

I'm looking for someone who has experience in holding down plastics to the table. The vacuum works for large sheets, but when I'm making parts that are 12" and less the bits tear them out of place. I'm currently using double sided carpet seeming tape and the stuff is a dread for cleaning. Any suggestions?


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## Errol (Dec 13, 2006)

Hi Jetvitch,
Have you had a look at V-Clamps? vac-clamp.com. This might help you on your quest.


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## pwdavo (Jul 25, 2006)

Having used my homebuilt CNC for some 6 years, I have tried almost everything. Now I use .5 throwaway MDF on bed and screw stock by corners, yes stock needs to be a little bigger but it works first time every time.


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## blurrycustoms (Feb 23, 2009)

I have had success with drilling a hole pattern in a 1/2"-1" thick MDF or HDPE table, say 5/16 holes on a 4"x4" grid, and then using a 1/4"-20 t-nut (similar to below) pressed into the bottom.










They run about $7-$8/100 pieces

Obviously you can use any grid spacing, but these t-nuts come a good variety of shapes and sizes from McMaster-Carr. This may extend the life of an otherwise disposable tabletop.

Just a thought!


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## Arcticfox46 (Jul 19, 2007)

jetvich said:


> I'm looking for someone who has experience in holding down plastics to the table. The vacuum works for large sheets, but when I'm making parts that are 12" and less the bits tear them out of place. I'm currently using double sided carpet seeming tape and the stuff is a dread for cleaning. Any suggestions?


3M - double sided sticky tape --- its wicked strong and simple.

I use it all the time on my CNC machine

Heck - I use in on non CNC too


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## CNCWOODWORKER (Oct 19, 2009)

Arcticfox46 said:


> 3M - double sided sticky tape --- its wicked strong and simple.
> 
> I use it all the time on my CNC machine
> 
> Heck - I use in on non CNC too


Can you tell me exactly which 3M tape you use? They got about a million it seems. Also, how much does it cost per roll? I'm looking for a replacement for my current brand.

I've tried probably a dozen types through the years and have found Do It Best Brand carpet tape in the retro 70's looking box to be the best, but they rarely have it at my local stores anymore and I can't find it on their website either. It's also expensive. 
This stuff is extremely sticky, and cleanup usually isn't an issue. 
I've used it to hold down hard maple guitar necks and bodies and done some pretty heavy routing with no problems - except getting the part off the table when it's done.


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## Axeman (Nov 3, 2009)

A little denatured alcohol releases the 3m tapes instantly.


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## BigJimAK (Mar 13, 2009)

CNCWOODWORKER said:


> Can you tell me exactly which 3M tape you use? They got about a million it seems. Also, how much does it cost per roll? I'm looking for a replacement for my current brand.
> 
> I've tried probably a dozen types through the years and have found Do It Best Brand carpet tape in the retro 70's looking box to be the best, but they rarely have it at my local stores anymore and I can't find it on their website either. It's also expensive.
> This stuff is extremely sticky, and cleanup usually isn't an issue.
> I've used it to hold down hard maple guitar necks and bodies and done some pretty heavy routing with no problems - except getting the part off the table when it's done.


+1 on the double-stick tape


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## LisaDavid (May 23, 2013)

jetvich said:


> I'm looking for someone who has experience in holding down plastics to the table. The vacuum works for large sheets, but when I'm making parts that are 12" and less the bits tear them out of place. I'm currently using double sided carpet seeming tape and the stuff is a dread for cleaning. Any suggestions?


I guess may it works for double sided carpet tape have all that capability which requires for vacuum works..
Check out eastern suburbs


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## fixtureman (Jul 5, 2012)

When I cut small parts I use a pressure foot


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## geotek (Mar 4, 2012)

Axeman said:


> A little denatured alcohol releases the 3m tapes instantly.


Be careful with DA around acrylic and polycarbonate. It can make the plastic craze and crumble. Not right away, but sometimes days later. I learned that when machining some acrylic parts. I had cleaned them off with DA after they were machined. The next day the box of parts was just a crumbling mess. They looked almost like tempered glass when it shatters.


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## Quillman (Aug 16, 2010)

Pinning, toggle clamps, sometimes machine screws.
Do it everyday.


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## fixtureman (Jul 5, 2012)

what kind of plastic is it. Does it have a protective coat on it if not try some vinyl transfer paper on it and then spray 3m 77 on it and use a sacrificial sheet


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## spiderlegs54 (Apr 4, 2012)

?? describe a pressure foot, please


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## fixtureman (Jul 5, 2012)

here is the pressure foot that I made


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## Keith Hodges (Apr 30, 2013)

I've been using a double sided tape from Lowes. Its got a blue plastic coat that you remove, and the sticky part peals off pretty easy once finished, leaving no cleanup. Pretty inexpensive also. Most double sided tape will move some if its hot in your shop, so, once I tape it in place, I'll take 4 small pieces of wood, put one on each side of the plastic, (acrylic), and clamp the wood. The tape holds the plastic down, and the 4 blocks of wood keep it from moving around. BTW, paint thinner works great on acrylic, with no problems at all. The sticky residue comes right off.


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