Unique Thimble Design Construction?

[WKevinD]

I was examining some early fowlers and one had a set of unique thimbles that I would like to copy.
Looking for suggestions. I form my thimbles using a vice, 1/4" tabs and 3/8" rod as an inside die, I use a rounded chisel and grooved flat plate to form rings on my annealed flat before folding and swaging my thimbles.
I am stumped trying to figure how to form the dimples and swage them round?

Thoughts, suggestions?

Kevin

[rich pierce]

The dimples would be formed just as the rings are, but punching from the other side of the blank?

[WKevinD]

The dimples would be formed just as the rings are, but punching from the other side of the blank?

But then pushed out when swaged around the rod...that is what has me stumped?

Kevin

[rich pierce]

The dimples would be formed just as the rings are, but punching from the other side of the blank?

But then pushed out when swaged around the rod...that is what has me stumped?

Kevin

Dang, and I thought I was smart! 

As far as I can figure there’s no way to make those!

How about this: the rod they are formed on has longitudinal grooves.

[WKevinD]

(How about this: the rod they are formed on has longitudinal grooves.)

Worth a try, I guess. Thanks Rich.

Kevin

[rich pierce]

(How about this: the rod they are formed on has longitudinal grooves.)

Worth a try, I guess. Thanks Rich.

Kevin

Just guessing and hoping someone else knows. One cool feature of the dimples is they would sort of gently squeeze the ramrod but the road would be thin enough to never bind.

[David Rase]

The dimples would be formed just as the rings are, but punching from the other side of the blank?

Rich,
I think you are right on track, you just stopped short.  If the material is thin like tradegun pipes are, you could slip in your dimpled rod, clamp the tab shut then with a round nosed punch dimple your pipe.  After the dimples are applied, unclamp the tab, slightly open the pipe and slid out your dimpled rod.  Close the pipe back up and voila!
David

[WKevinD]

The originals used fairly thin stock (that I never measured) so the dimples should form easily in annealed stock.
Combining Dave and Richards suggestions I'm now thinking about using a 1/2" forming rod with drilled dimple recesses, dimples formed with a rounded punch, open tab, slide off pinch and solder tabs. I'll give it a try when I get out to the shop this AM.
Thanks, I think.
These were on a 60" barreled Hudson Valley Fowler so I don't think 1/2" OD pipes would be that awkward.?

Kevin

[rich pierce]

The dimples would be formed just as the rings are, but punching from the other side of the blank?

Rich,
I think you are right on track, you just stopped short.  If the material is thin like tradegun pipes are, you could slip in your dimpled rod, clamp the tab shut then with a round nosed punch dimple your pipe.  After the dimples are applied, unclamp the tab, slightly open the pipe and slid out your dimpled rod.  Close the pipe back up and voila!
David

BANG! You nailed it!

[P.W.Berkuta]

You could also try a two-piece form. One half that is half round with hold drilled in it to form the dimples and the other section to fit under the first half as a buck. Slip the two into the thimble make your dimples then knock out the bottom section then the top section will fall out.

[Jim Kibler]

Punch and form everything flat and then just wrap it around the appropriate sized rod.  The dimples shouldn't effect the rolling process too much.

[kutter]

Form the thimble in the normal fashion from flat stock.
I'd use thinner stock than normally used because of the need to dimble it later.

After forming round which includes the normal legs or flanges for pinning,,clamp & hold the thimble tightly closed and pour the inside full of lead so it is completely solid.

Then go about dimpling the surface , the lead supporting the brass from the inside for the operation.
I suspect it would take a bit of practice on the part of the 'smith to get the right convex punch size, depth and hammer wack to get
the dimples to appear the way you want them too.
Perhaps reheating the thimble to let the lead re-melt and re-occupy the inside at some point during the process as it gets displaced,,maybe.

When done, heat it up, drain the lead out.  Clean it out w/a brass brush run in and out of the thimble while the lead is still molten. That should 'tin' the inner surface and not leave extra lead in there to decrease the diameter.
Probably could get the flanges to solder together at the same time too.

It always works so great on 'paper'.

[smylee grouch]

I have made a few. It seems as though when I used a 3\8 drill bit my forward pipes were a bit tight as I wanted a tapered rod so I soldered a small strip of brass in between the tabs on the forward pipes and this gave me just enuf clearance for the tapered rod butt not overly big looking.

[WKevinD]

Smylee I like your thought... Jim I need to try but worry about pushing the dimples out.

I set up for a quick try with an oversized rod (1/2"hickory scrap) and used a 5/16 piece as a punch on .016 annealed stock. I worked OK but the next attempt I'll mix the tapered rod configuration I usually use with Smylees shim idea and Jims suggestion to punch while flat.

It's a process...thanks for the input

Kevin

[smylee grouch]

Kevin, if I remember right I used a thinner " shim " on the center pipe and then one just a tinny bit thicker on the end pipe so I could make the rod taper almost full length but still not as big as the next size ( 7\8 ).

[bluenoser]

This is an interesting thread.
The rod appears to be a snug fit at the end of the thimble, so I don't see how dimples on a straight barrel would work.  I don't think the thimbles are straight sided.  I think they are barrel shaped in the dimpled areas and the dimples likely  reduce the ID to about that of the ends.

[Jim Kibler]

Nah, you won’t push the dimples out.  When firming them, you’ll work harden them to some degree.  Bend a paper clip to a sharp bend and try to straighten it out at the bend. 

Ex-Metallirgical Engineer

[WKevinD]

Nah, you won’t push the dimples out.  When firming them, you’ll work harden them to some degree.  Bend a paper clip to a sharp bend and try to straighten it out at the bend. 

Ex-Metallirgical Engineer

I'll try, thanks!
Kevin