MTFCA Forum

First, a little history.

A few years ago I slid off a muddy road and into some branches that broke a top socket. A friend who was an old body man fixed the socket so it looked good as new.

But my September trip undid the fix. Bouncing on bad roads and recurrent battering by wind from passing trucks broke the socket at the weak spot where it was broken before.

I stopped at the Reddings' place and Bud applied a temporary splint to get me home.

That brings us to the question. In October I picked up a new socket at Hershey. But as you see here, it's only the crimped sheet metal tube. I have to use the old hardware from the broken socket.

I don't expect any trouble with the riveted parts. I know what to do there. But I'm not clear on how to get the cast base (left) out of the sheet metal part (right) and install it in the new socket (top). I hope somebody with experience on this job can provide some guidance.

Steve, If I was to tackle the task I would wirebuff/sandblast/handscrape all the paint off the original forged ends to see how the tubes were attached. Then the old tubes can be ground off back to the parent metal of the forgings. Check the fit of your replacement tubes at this stage. Most likely the tubes were bronze welded to the forgings, and I would do the same. I would first use bronze material to "tin" the forgings, so that when the tubes are fitted, all you really need to do is sweat the two pieces together. To this end, there are bronzing alloys made for close tolerance work like this. Sweating bicycle frame tubes and butts together is one similar application. It would not hurt to drill a couple of 1/4" holes in the tubes, a little below the depth of the forgings, so that additional bronze can be flowed down the tubes.

I would cheat a little, and attach the anchor point castings the same way, using the rivets as insurance for the bronzing, and to preserve the original appearance.

Hope this helps.
Allan from down under.

As Allan suggested, I wire brushed the paint off the joint. It looked like the parts were put together with body solder, not welded or brazed.

So today I applied enough heat to melt out the solder and the parts came apart easily. Attaching the new socket to the base will have to wait until I buy more solder.

Might have to wait to save up enough $ to buy a roll of solder. Every time I have to buy another roll it's sticker shock.

Dick

I don't know if this would apply to your situation, but in a recent conversation with RV Anderson he recommended removing the wood filler at the bottom of the sockets and filling them with pourable epoxy. The epoxy is supposed to prevent corrosion and provide additional strength to the tube. Something to consider after you put yours back together.

I wonder if others have done this and what they think of it?

The epoxy filler may be a good idea. I'll look into that.

Today's work on this project was attaching the new socket to the base. I slathered flux on the inside of the socket, and on the base stub that fits inside, lined up the two parts, dropped a coiled few inches of solder down into the socket, and applied the heat.

The result seems to be a good, solid connection between the two pieces.

All the body solder I have left is that little chunk sitting on the vise. It will take more than that to build up the base to the same size as the socket, so this job is on hold for a few days until I get more.

Steve, I can see why solder was used. I believe you are working with reproduction top bows. Originals with which I am familiar all have steel castings for the bracketry, rather than the brass your photos show. Consequently, brazing would be the way to go, but not with your brass components.

Silver solder would make for a stronger joint, but that would be somewhat expensive!!!!!

Allan from down under.

Looking good Steve. When I brazed mine I sprinkled some flux around the surfaces and built a cave of fire brick around the standing assembly. This allowed me to heat the parts to an even temperature. I had dropped a brass rod down the tube and eventually the brass flowed into the seam and began showing up outside the tube.
I filed the sleeve rather than filling at the bottom.
Does your assembly have an inner sleeve as well as the seamed sleeve?
I would give the epoxy some thought. I have heard this can make the assembly too rigid. The bow twists and flexes much more than one would think and being rigid all the way up can cause it to crack at the weakest point.

I believe you are working with reproduction top bows.

That wouldn't surprise me. I'm pretty sure this is a 1970's 1915.

Does your assembly have an inner sleeve as well as the seamed sleeve?

No, it's just base and tube, with nothing inside the tube.

I believe my '15 has the repro top sockets and they work fine. They do have bronze ends. The original irons had the seamed sleeve with an additional inner sleeve that was open and slid inside the seamed sleeve. The pictures in this post show some of that.
http://www.mtfca.com/discus/messages/70 ... 1506904799
I doubt if any paint got inside the factory irons. The two layers create a moisture trap probably from condensation and that is why they are often rusted out. My first top was a '25 which I painted and put on the car. One Winter a foot of snow accumulated and the irons collapsed. They were rusted badly but not through and failed where the sheet sleeve meets the forging. Those later irons don't have the inner sleeve and are thicker metal with a butt seam not welded. Old irons may look good but beware.