Trying to find a better hold down system.

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SIBUD
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Trying to find a better hold down system.

Post by SIBUD »

I'm looking for any and all pics/suggestions of hold down systems people are using.

Please describe why you use your system and why it is better than what you had previously.

Thanks in advance.
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Re: Trying to find a better hold down system.

Post by Adrian »

It's worth doing some searches. This has come up lots of times before. I know I've posted the clamps etc I've used at least three times on here.

Currently I use a system of T-tracks and clamps but I'll be changing soon to less tracks as I use jigs rather than clamps for smaller parts and most of what I cut is in 8x4 form.

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Re: Trying to find a better hold down system.

Post by Zeropoint »

Hi All
I've stumbled along with a variety of methods - some good & some not so good.
The best so far is that I cut a piece of MDf oversized to my work piece & clamp this to the machine bed with metal step clamps.
Then I line up work piece on this spoil board & clamp it down.
Next step is to drill holes in appropriate places, clear of machining, & I screw the work piece onto the spoil board.
Remove clamps holding work piece.
The work piece is now clear of obstacles, secured to the spoil board below & the job can start.
The added advantage of this is that if it is a double-sided machining task, the drilled holes will line up the work piece if you need to flip it about either x or y axis.
The down side is that you end up using a bit more material for spoil boards & need to do a regular flycut to recycle the MDF as long as possible.
I try & post some pics on my next run.
Rgds
Mark

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Re: Trying to find a better hold down system.

Post by larrybadgett »

You might check out this topic. I posted a system that i use to clamp toward the end that i'm still using today since it is working well for me and is very simple.

viewtopic.php?f=28&t=13270
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Re: Trying to find a better hold down system.

Post by Leo »

I don't think you find a one size fits all system.

Workholding is situational.

Sometimes I use a drill press vise.

Sometimes double sided tape

Lots of times I just drill a hole in the piece and screw it down to the sacrificial board

There are "T" slots with clamps. You could build a vacuum table. There are "mighty bite" types of clamping systems.

There are LOTS of systems out there and not a single one will be one size fits all.
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Re: Trying to find a better hold down system.

Post by Carrie V »

Another option that works for me sometimes ,you can Premask your part/Sheet, then use a can of 77 adhesive spray on Premask and stick it to MDF table top.

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Re: Trying to find a better hold down system.

Post by JimG »

I normally work with double sided tape or clamps. But recently, when cutting small parts, I've started machining from plate of appropriate thickness and of much larger size so that the plate can easily be clamped at its edges with the clamps well away from the cutter. The parts are cut with tabs so that they won't break away at the final cut through and are sawn out of the plate with a piercing saw when it's removed from the machine. It can be a bit wasteful of material since you have to leave reasonable margins around any cut pieces to support tabs for any further pieces being machined. It also helps if the plate is flat, but I can do a bit of fiddling around the area where the part is being cut to get that area as flat as possible.
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Re: Trying to find a better hold down system.

Post by larrybadgett »

Try this link as it looks like the last one doesn't work!

http://forum.vectric.com/viewtopic.php? ... ing#p92056
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Re: Trying to find a better hold down system.

Post by COWBOY1296 »

I know those that have the vacuum hold downs swear by them, but I am happy with t-tracks and clamps. This is an old picture and I now have tracks that run the full width of the table and have more tracks then what are shown. The next time that I do them I will cut the pockets deeper so that I can re-surface the table without hitting the t-tracks.
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Re: Trying to find a better hold down system.

Post by wonderpilot »

I use a bunch of different methods as they have already said..for each application.
I use an aluminum die plate that is drilled & tapped every 2" for 5/16x18.
I use an aluminum backer bar and then wedges off the bolts on front and one side
This keeps the piece in one place and doesn't interfere with the cutter.
This seems to work for me!
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Re: Trying to find a better hold down system.

Post by rscrawford »

My favourite method is a vacuum jig. I use a pallet system that fits over an aluminum plenum on my table. The pallets fit in exactly the same place every time, and are held in place by vacuum (and a hole through the pallet allows the vacuum to clamp my workpiece as well). This way, I can change jigs in seconds and always have them indexed exactly to the table.

For 4x8 sheet material I use a larger vacuum through my spoil board. I also have t-track around my different plenums for holding with clamps.

My favourite system, as of late, is nailing with composite nails. Nail through the sheet into the spoil board, and then cut them flush with the spoil board when done. I think they're called Raptor nails. 15 gauge - I use anything from 1/2" to 1.5" depending on the thickness of my workpiece.
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Re: Trying to find a better hold down system.

Post by Ms Wolffie »

I use the Raptor staples, will get the longer nails next time.
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Re: Trying to find a better hold down system.

Post by Lameiii »

I'm not familiar with Raptor staples. Can you tell me a bit more and where I might obtain them?

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Re: Trying to find a better hold down system.

Post by 4DThinker »

Raptor staples/nails/fasteners are plastic. http://raptornails.com/

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Re: Trying to find a better hold down system.

Post by larrybadgett »

Anyone have an idea where they can be purchased or ordered in the US? I've done a little looking around and have been unable to find them.
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