Looking for suggestions (pics) for work holding options

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larrybadgett
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Re: Looking for suggestions (pics) for work holding options

Post by larrybadgett »

Woodchip,
I saw those, they look interesting. I was wondering, with the eccentric holes do you just turn the circles until snug then tighten the bolt and be sure it is tight on all sides? Have they been holding up well? Where did you get the o-rings? Similar to cam clams without the handles.
Yes, the eccentric holes are turned by hand to tighten on the material then the bolt is tightened to hold from turning. The ones with the hole centered is used as a backstop. O rings were ordered from McMaster and take up variances in dimensions of the wood piece along with holding the eccentric ones from turning. I have been using them for several years with very good results. Easy to make and easy to use which makes easy to replace. I used brass for centers but it could be plastic, wood or any material that would not damage a router bit. Since all the spoil board holes are threaded you can also add downward clamping for warped material. I like them and as I've said I have been using them for years now.
Woodchip
Wud Bi Tek
http://wudbitek.com/

Tundraman
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Re: Looking for suggestions (pics) for work holding options

Post by Tundraman »

Woodchip,
Thanks I think there is some very good information there. I may not use it all but I'm sure I will use some of it.

Micheal,
Can you direct me to some more information on the VAC table (drawing or sketch of dimensions, etc.)? I would like to make something along those lines. Its looks like about a perfect size.

Charlie_I,
Those are nice simple straight forward hold downs. I only have V-Carve 8 but they shouldn't me too hard to draw up. Thanks for the offer. I made some out of solid surface material for my original small machine. Overall they have worked pretty well but I can see after using them for a while, many advantages being longer and lower profile.
SS Hold Downs.JPG
I glued 2 - 1/2" pcs of SS together and cut these out. The circle pieces didn't work for the pivot on top so I used sections of dowels. The star knobs were cut from some plywood scraps, glued a 1/4" nut in the recess. Same thing with these materials not mattering if the cutter gets too close. :)

Thanks again to all and if anyone else has any ideas to share - please do.
Scott

Tundraman
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Re: Looking for suggestions (pics) for work holding options

Post by Tundraman »

There are a lot of views - no other work hold suggestions or pics anyone wants to share?
Thanks,
Scott

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zeeway
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Re: Looking for suggestions (pics) for work holding options

Post by zeeway »

The most dependable holddown method from my experience is the use of screws through the scrap area of the material. I have clamps of all kinds sitting unused in drawers - because they occasionally let loose, ruining the material (must be the clamp's fault...not mine, hah).

I do resort to clamps when there is no waste material to screw thru...but I try to remember to take light cuts.

The downside to the screw method, is that the spoil board has little raised knobs from removed screws that I will run a chisel over to remove...between spoil board re machinings.

I am intrigued by the threaded inserts embedded in the spoil board...and I am thinking about giving that a try. My ideal solution that I am thinking through is the use of "pallet fixtures"...which would be made to the spacing of the embedded threaded inserts, as a fixture which mounts on the table and can index to a repeatable location.

But that also takes patience...most times I just want to get on with it...

Angie

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scottp55
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Re: Looking for suggestions (pics) for work holding options

Post by scottp55 »

Angie,
Just in case you ever try a job specific jig with the inserts.
http://www.amazon.com/dp/B002KSZ13G/ref=biss_dp_t_asn
I was a little nervous about using Zinc inserts at first, but with 300+ inserts I've only had two failures. First one the thread only caught half the insert thread and I CRANKED on the wrench and it snapped. Second was a severe cross thread and when tapped again, there wasn't enough meat left and I stripped the threads off.
Had a couple of "Spinners", but that was due to a soft spot in the LOUSY Lowes MDF and some Medium CA soaked in Very well to the surrounding MDF and beefed it up and stopped the problem.
One nice thing about those inserts, is that if you're a total moron and choose the wrong hole and try to profile/spiral ramp MDF and chose the insert hole by mistake.... a 1F upcut is unharmed :oops:
Not sure about surfacing them at MDF speeds, as I haven't managed to make that Oopsy yet.
Most of our stuff is multiples, and even using CA on the screw "volcanoe's" and a cabinet scraper, there were only so many times we could cut a file before changing the screw location or the material.
I'm thinking like you for using them with my vac fixture(IF I ever get aroundtooit), and for a spoilboard/spoilboard for use with Tailmaker where the bit cuts 1/2 Diameter into spoilboard.
Just thought I'd mention I was happy with those .512" length EZ's.
If you buy the tool(WOW!!! 3X what I paid now? think I'd chuck a cut-down Allen now),
http://www.amazon.com/E-Z-LOK-Drive-Too ... MCHRWC2FTH
it only puts it flush, so insert from bottom of your "pallet jig".

scott
"One accurate measurement is worth a thousand expert opinions"

GMH


scott

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