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Stu Gillard
05-25-2018, 6:51 AM
I picked up some old calipers that I want to use to turn a set of tool handles.

386465

Presently they are too loose to use.
Does anyone have any tips to tighten them up?

Heat and peen the pin with a ball hammer?
Heat and center punch around the pin?
Cold peen?
Cold center punch?

I'm hoping someone has needed to do this in the past. There's scant information online.

Cheers all,
Stu

Bill Houghton
05-25-2018, 9:44 AM
I would just try bashing on them with a suitably heavy hammer, with the caliper joint resting on a block of steel or iron. Firm joint calipers are tricky: you want tight enough to hold but loose enough to move. So hit/test/hit/test.

Jim Koepke
05-25-2018, 12:54 PM
Tapping lightly seems better than "bashing on them with a suitably heavy hammer."

Better still would be a caliper with an adjustment or tightening screw.

386486

On the upper left is one with a tightening screw. The caliper is set and then the center screw is tightened to lock the setting. There is a secondary fine adjustment screw that is handy at times. This caliper is made to do inside and outside measurements.

At the bottom right next to the slide rule is a caliper with a long threaded rod to set the caliper to a measurement.

The calipers in Stu's picture are a quick set comparison type. They are not really made to hold a setting while being picked up and set down constantly like would be taking place on a lathe.

jtk

John K Jordan
05-25-2018, 1:17 PM
I never heat heat but just peen lightly with a punch and small hammer with an anvil or heavy steel plate behind. Rivets are rarely hardened.

However, at the lathe I don't like calipers that can't be locked since they always tend to open up in use. I have a drawer full of these cheap verniers and use them a lot. Found a real deal on them once. I round the points a bit so they will slip nicely over the work.

386492

All the other calipers and dividers I use at the lathe have screw adjustments to keep them at the desired setting. Some are spring loaded for ID use and checking wall thickness. Some are visible in these photos.

386493

If you want some dimension on a bunch of tool handles to be the same diameter, say to fit the ferrules, another option is to cut a slot of the right size in a piece of say, 1/16" sheet steel. Round or bevel the corners. As you reduce the diameter of the wood push the metal template against the back until it slips over the tenon. The steel will go over the tenon when it is still a tiny bit too large and compress and burnish a groove in the wood. Turn down to the level of this burnished mark and the diameter is perfect.

JKJ


I picked up some old calipers that I want to use to turn a set of tool handles.

386465

Presently they are too loose to use.
Does anyone have any tips to tighten them up?

Heat and peen the pin with a ball hammer?
Heat and center punch around the pin?
Cold peen?
Cold center punch?

I'm hoping someone has needed to do this in the past. There's scant information online.

Cheers all,
Stu

Richard Line
05-25-2018, 3:37 PM
My thought, for your planned use, would be to drill out the rivet or pin and replace it with an appropriately sized bold and nut, probably would also want washers. That way you could lock them down. Of course finding the right size bolt and a easy to use nut may be a bit of a hunt.

John C Cox
05-25-2018, 4:06 PM
Clean the hinge pin off good - they look like they have little pin holes in them - perhaps you will get lucky and fond they are screws which tighten with a pin spanner...

If they are real soft like a rivet and don't have any sort of provision to tighten them - perhaps use the pin holes already in them with a good center punch and lightly upset the rivet a bit at a time until it tightens properly...

Stu Gillard
05-25-2018, 7:51 PM
Thanks all for the ideas.



The calipers in Stu's picture are a quick set comparison type. They are not really made to hold a setting while being picked up and set down constantly like would be taking place on a lathe.


This is exactly how I want to use them. I do have a set of the screw type calipers that I use for fitting the tenon in to the ferrule. I just don't have multiple sets :(
I suppose the bottom line is they are currently useless and I don't want any of my tools to be useless.

@John K Jordan
Great ideas. I don't do much turning, but a metal template to size the ferrule tenon would be useful.
I figured that these calipers would be an easy way to get some consistency in the profile (quick comparison).

@John C Cox
Those little pin hols look like someone has tried to tighten them in the past with a punch. They aren't screws.

I intend to turn a new set of handles for my HSS lathe tools. Sort of like using Internet Explorer to download Firefox :D

I'll try working around the rivet with a center punch on an anvil.

Jim Koepke
05-25-2018, 8:01 PM
I suppose the bottom line is they are currently useless and I don't want any of my tools to be useless.

Well then, just how industrious are you and how much odd hardware can be found in your neck of the woods?

With a bit of imagination, a few tools, some long pieces of threaded material a few nuts and some shoulder bolts you could turn these into calipers with fixed setting abilities.

jtk

Stu Gillard
05-25-2018, 8:12 PM
Well then, just how industrious are you and how much odd hardware can be found in your neck of the woods?

With a bit of imagination, a few tools, some long pieces of threaded material a few nuts and some shoulder bolts you could turn these into calipers with fixed setting abilities.

jtk

That would be ideal ..... when I retire :D

They would be fit for (my) purpose if they were tight.

The tool handles won't be turned anytime too soon.
I have two colonial aussie red cedar chest of drawers to restore (commissions) and two bar stools to build for SWMBO. All while working a 9 to 5 job.

Sigh

Jim Koepke
05-25-2018, 8:19 PM
The tool handles won't be turned anytime too soon.

My luck has been pretty good doing tool handles and such by eye.

It can be handy to use a caliper or even an open end wrench for getting a consistent size turning.

jtk