Holding Down

[lutchman]

Hey guys, i figured out that my weakest aspect of this whole cnc operation is the hold down. is there any advice, reading material, links or even videos that you pros can point me to so i can turn my weakness into my strength. it would be greatly appreciated. thanks.

[cowboy1296]

There are a few differant ways to hold down your project. I use t-tracks and the clamps that fit in them. I cut pocket cuts in my table big enough to put the t-tracks in just below the surface. You can never have too many. The tracks are available from differant venders but I chose Rockler

[burchbot]

Here is a video you can watch. http://www.youtube.com/watch?v=bBUm59_9Bks&feature=youtu.be
Dan

[gundog]

Your question is hard to answer not knowing what machine you have and what you are trying to hold, how big, and made from what? Provide those answers and people can help you better.

I cut plastic sheet goods and make some very small parts I hold my material with a home built vacuum system. I do not usually cut completely through the material and trim the parts out using a laminate trimmer.

Mike

[chiloquinruss]

I do mostly sheet goods so t-track works for me. Russ

http://hobby-tronics.lenzus.com/content/21775739/r/s_84086157.jpg

http://hobby-tronics.lenzus.com/content/21775739/r/s_32436157.jpg

http://hobby-tronics.lenzus.com/content/21775739/r/s_32426157.jpg

And then like everyone else you make up jigs for the smaller stuff or half sheets, etc,. The jigs get held down by my t-track system. Some of the larger jigs have t-track on them as well. It's hard to give an answer not knowing what you want to hold down. Russ

[donek]

simple and cheap vacuum table tutorial here:
http://donektools.com/cnc-basics-tutorials/

[Bob Eustace]

Email TJ at Shopbot and he will send you the file for the basic methods. Also has a one hour video on clamping.

[bcondon]

I recently started using vacuum and would never go back to anything else.

Please see my post of today about vacuum with pictures.

The investment was minimal and for small items, it works fantastic!

Bob COndon

[lutchman]

we do many different jobs on a daily basis, sometimes its a 4'x8' fretwork job or sometimes its a 4"x4" etching job...so holding down is always different. we have a 4 zone vacuum system in place but sometimes it dosent work for irregular shaped projects. i looked at the TJ video but it only involved holding down with square pieces, i will try to take a pic of some of the work that we do so you all will get a better idea what i am trying to do...(once i get permission that is). but overall, i would like to thank all of you for your continued input and suggestions.

[bleeth]

If your pieces are flat and not prone to bowing a good hold system is cam clamps. David Buchsbaum sells some very well made ones, but I have cranked out a bunch of them on the mill just by cutting some small paddle shapes (similar to a ping pong paddle look but smaller) out of plywood and offsetting a screw hole a 1/4" toward the handle. You can then screw them wherever you want on the table to hold your part. The system allows you to cut anything into the part, but you cant do profile or cutout passes.

[lutchman]

i tried one of the "gigs" on tj"s video and its working ok for now...thanks for all your help, i think i am getting better...lol...any literature on the hold downs?