Anyone make a homemade Holddown that adjusts to tighten from the side?

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kristenanne77
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Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by kristenanne77 »

Has anyone made a homemade hold-down clamp that would adjust to fit snugly laterally against the workpiece on T-tracks.
In my mind I was wondering if there was a way to use a small turnbuckle between two pieces in the the track rails and use the turnbuckle to tighten one end against the workpiece.
The idea is in my head so I have no idea if it is even doable. Or any other suggestions on making an adjustable holddown similar to the rockler one below. . Although I see many different designs for DIY clamps, I haven't seen any for this this type of clamp. (sometimes it's worth just buying the thing, but sometimes not)

https://www.rockler.com/rockler-auto-lock-t-track-clamp

Thanks
K

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highpockets
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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by highpockets »

You might look into cam clamps
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SteveNelson46
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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by SteveNelson46 »

When I don't use screws to anchor the board to the spoilboard I use these. Handy!

https://shop.opticsplanet.com/shop-fox- ... ouEALw_wcB

Andrew Pitts has a video on YouTube on maing a small 2-sided bowl and shows how he made his own clamps. Clever idea.

Steve

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FixitMike
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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by FixitMike »

Not homemade, but I found this clamp to be more effective than the Rockler one, since it moves downward as well as sideways as it is tightened. I improved it by replacing the bolt with a hex head bolt and spacer. The hex socket bolt would fill up with sawdust.
Shop Fox D3347 Cam Clamp (Available from Amazon)
CNC clamp.JPG
I found that the Rockler clamp tended to lift the material from the table as it was tightened.
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Experience comes from bad judgement.

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gkas
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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by gkas »

Here's another couple of options.....

CNC Nutz Cam Clamp https://www.youtube.com/watch?v=r4-dufCwGEA

I have a couple of the side clamp kits from Axiom Precision. I use them pretty much daily. I'm just too lazy to make them. https://www.axiomprecision.com/accessor ... p-kit.html

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TReischl
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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by TReischl »

Cam clamps can and do work. That said, you need to be careful with them. Two reasons:

If you use a spiral flute upcut end mill and get too aggressive you can lift the material out of the clamps. This is especially true on smaller parts.

Secondly, vibration can release the clamps unless you are near the full stroke of the clamp.

Another solution is to build a vise. I built a pair several years ago and use them constantly. Been thinking of making another pair that have more opening.

Oh, one other thing, if you use a cam clamp and then rout around the outside of a piece the holding force can be severely reduced if there is not enough material left. Not good.
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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by Tailmaker »

I made a flat clamping vise for my little mobile CNC, see video below. It consists of 2 sturdy plywood bars that are closed by 2 metal Harborfreight clamps and which are held town with 4 carriage bolts and knurled nuts onto the t-slot table. The cutout for the clamp rods is tapered so that the rods can wiggle a bit and it can clamp blanks that are not exactly parallel. Works pretty well and easy to do. The plywood bars consist of 2 symmetrical halves each with pockets for the clamp rod.
I clamp the work piece while the t-slot bolts are only hand tight and then tighten it down to the table. Sometimes I use spacers under the work piece to make sure it is parallel to the table.

https://youtu.be/IjtcaGbSX9U

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Tex_Lawrence
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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by Tex_Lawrence »

Here are two variations that work well:

Tiger Claw Clamp

Gator Tooth Clamp
Crooked Wood Products - Custom Wood
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kristenanne77
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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by kristenanne77 »

Thanks.

Lots of great ideas.

K

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Re: Anyone make a homemade Holddown that adjusts to tighten from the side?

Post by kstrauss »


These are metal and that style works well on my CNC. Similar clamps could be made from a hard and slightly springy wood such as maple. Note that if you press hard on the edge of thin stock the middle will bow upwards. It helps if you apply force on the neutral plane or centre of vertical height.

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