rivets in hand tools

I just got pair of Starrett #1 - 5-1/2 carbide tipped nippers. They look like this

formatting link

Go there if you want new ones, I suppose.

The rivet sticks up from the surface on both sides about 1/16" or so and is completely flat. The ones I got had a rough life and have far more play than was acceptable due to the wear on the rivet. I ground it out with a die grinder with a bit of fuss.

The form was as expected, a rivet with a washer-ish side peened over on the other side with the connecting gap barely visible. They did a nice job blending it all together. It was not easy to tell which side to grind away at first. When I saw the gap I tried to break it out with an arbor press, but that did nothing at all.

The shaft of old rivet was quite worn and had a weird staggered offset to it. I machined a new one out of 1/2" 1018 round, and got a nice fit to the jaws. Next step is get the washer side in place and make it look good. My guess is the washer side should have a real tight fit and a radiused outside face where you peen the shaft over for a solid fit.

My question is, how do I do this and not bind up the tool? There was no shoulder or step on the original part to prevent the washer side from being pressed against the jaw too hard. There were also no antirotation type patterns like star shapes, cut-outs or anything like that. Was the washer heat fit by chance? I can get this tool mostly up and running the ugly way, buy really want to know what they did at the factory.

It's got to be similar magic to the joint in wire cutters of needle nose pliers. Not really sure how how they get such a precise fit.

The only other part I broke was a screw for one cutter. It's a 6-40 thread screw with a shoulder. Sort of a screwy item. If I jump in and make one of those is 1018 ok or is there something better to get for medium+ strength screws? I've made leaded steel screws and stuff like that, but none really needed any strength. This screws is available from starrett, but I'm sort of curious about how to just make it. The original one broke from being stretched too much. It turned greyish white and the threads popped off.

Reply to
Cydrome Leader
Loading thread data ...

What if, instead of being a single piece, the main joint pin was two halves, with a central pin knurled or glued to hold them together? That would limit the travel as the two halves were pressed into place, and would fit with all else you describe. There's no huge force spreading that axle, what matters is mainly the diameter matching the socket holes in the arms.

That would explain why you find no sign of peening.

Reply to
whit3rd

I would have made some threads on the pin and used a thin nut. Probably hit the nut by the threads in several places with a sharp punch once I got the tension where I thought it was good. Thin lock nuts are hard to source...

You may be able to put a thin shim in between the jaw and handle. Maybe fork shaped. Then just peen over your "rivet". Then pull, work out the shim and hope there is a bit of play.

Usually hex head bolts have a spec, hopefully this link works:

formatting link

Maybe make a custom size washer in place of the shoulder?

Reply to
Leon Fisk

You could set the rivet with its head supported, then place the tool over a hole that doesn't support the head and tap the other end until it's loose enough.

-jsw

Reply to
Jim Wilkins

I had a couple of pairs of very high-quality shears that they gave me when I left Ranger Yachts many decades ago. They were used for cutting fiberglas s fabric, and they considered them to be worn out. I said I thought I could fix them, so they told me to take them.

Anyway, the pivots were threaded on the end but the screw slot on one side was ground off. There was a thin washer and a thin nut on the other side. T he "rivet" was peened over the nut -- with a good rivet set, because they w ere nicely rounded -- and there was no other way to adjust the tension.

I also have a range of rivet sets, which I inherited, and I adjusted the lo ose pivots by carefully tapping the rounded head with a rivet set, laying t he flat side -- the ground-off end of the threaded "rivet" -- on my rivet p late, which is a 1-foot square of 1/2-inch c.r. steel.

I found them very easy to adjust that way. Just keep trying them after each modest whack on the rivet set. Make sure they're cleaned, sharpened, and r e-curved, if necessary, before whacking the rivet.

It sounds like it should work with your nippers -- and you don't even have to worry about re-curving them. The rivet set is a neat touch but I'd just use a ball-peen hammer if I didn't have them.

Reply to
edhuntress2

Ugly Way - I repaired a knife my son gave me once by turning a shoulder bolt and a nut that were a matched set domed on both sides on the lathe. When assembled I made two uniform punch marks at the seam between the nut and the bolt. When you look at it all you see is the two punch marks that look more like a driving feature in a security screw head than anything else. The belt clip broke and other things on the knife has worn over the years, but my home made shoulder bolt is still nearly perfect and the knife swings up and closed easily. I used an old stainless bolt as the working stock for both parts. It looks almost like a rivit except for the two peen marks. It was the first really useful thing I did on the mini lathe back in early

2006. (My wife gave me the lathe for Christmas 2005)
Reply to
Bob La Londe

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.