Thread: Big Clamp Down

For some while now I have had a number of clamps languishing useless in the shed because they either were missing handles, which renders them almost useless as there is little leverage, or missing the little wobbly bits on the other end of the screw thread, which is even worse.

I was loathe to throw them away as I knew the handle issue was relatively easy to fix as I just had to be motivated to replace them, but the little wobbly bit was much more of an issue. I was really disappointed that one of these clamps was a largish engineers style "F" clamp and really felt that shouldn't have happened, but it did. Some of the clamps were also missing the ball that fits into the wobbly bit.

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Showing the missing ball on one clamp.

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The ball was replaced by suitable sized balls salvaged from old ball bearings and welded in place. Fortunately the clamp lends itself very well to holding them in place. This is before welding:

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After welding the ball in place a "pad" and a sleeve is needed. I thought I had taken pix of those processes, but apparently not so I will have to describe it. For the pad I used some waste round bits of metal retrieved from our hole punch at work. If I had not had access to that I would have either cut suitable bits of round bar to achieve a circular flat pad or used a washer. The hole in the washer is not an issue, but in the next step a piece of tube is welded onto the disc so the sizing needs to suit. It also needs to fit easily over the ball.

Once this is done about eight slots are cut in the top half of the tube (four cuts with a hacksaw) so they can be bent in to close around the ball. I got the idea from another thread but it only linked to a video elsewhere so I am not inclined to pass it on. One thing I did find out the hard way is that it is much better to weld and then cut slots. This enables you to modify the length of tube and minimises blowing holes in the relatively thin tubing. I had stainless steel tube and consequently had to use SS welding rods. I only had 3.2mm rods and really I should have used 2.5mm rods or possibly smaller.

I found that to crimp tightly around the ball I had to crimp the tube a little and resaw again with the hacksaw.

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I have at this stage just left the attachment crimped as further welding would be disastrous. It may work just fine as the pressure is always into the socket, but if not, my fallback plan is to work some two part epoxy into the saw cuts and rotate the wobbly bit so it does not glue up solid, which is the main danger.

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Not quite as pretty as they could be, but at least I have four clamps that were previously useless.

There was no real need to go into detail regarding the rehandling of the other clamps other than to explain how they are held. There were two different styles and sizes.

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For the moment with the three smaller handles I have relied on two part epoxy to hold the handles in place but I may need to pin them at a later date.

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For the larger handle on the right, it was held by only a short length of screw thread and I used the existing hole to rivet through the ferrule: The "rivet" is a nail cut down and peened over. I need to do some work on the beam as it is horribly bent . If the handles on the smaller clamps look like moving I will treat them the same way and rivet them to the stem. The ferrules were whatever the first pieces of tubing that came to hand. Two are stainless steel and two are brass.

Eight more clamps ready to go to work. Timber is Forest Red Gum.

Regards
Paul