Frame Restoration

[Steve Little]

Thanks guys. Yesterday was a bit of a day.
I now have 6 rigid forks to check, and correct, for this information gathering eccercise.
Three of those are Offset rear legs. I plan to stay on this task until I have completed them all.
Aside from the information I've posted, I have picked up some other interesting information just by looking them and working with them.
I had better write it all down at the end of the job so that I don't forget it.

Pete. I have made this jig with the smaller And larger stems in mind.
The end inserts of the stem fixture are removable, so that we can accommodate the 7/8" stem, or whatever size we want to put in.

[Peter Cooke]

Pete. I have made this jig with the smaller And larger stems in mind.
The end inserts of the stem fixture are removable, so that we can accommodate the 7/8" stem, or whatever size we want to put in.

Excellent! I'll be living back in Melbourne so that works out nicely. In the meantime I'll try and track down some factory dimensions.

[Jerry Wieland]

I hoped that the online presence of this springer project, might tease out some knowledge or information on this extremely vague subject.
Perhaps a springer blue print, or a HD springer straightening manual.
But not to be.
Aside from some well placed advice on cat herding, (albeit a little vague in technique) and Kyle’s (very helpful) advise on the forward sweep measurement, I was sure I could hear the occasional chirp of a cricket.

The hook attachments are tough and worked well. I used them in conjunction with the ram to straighten the 41-46 fork.

Steve I was hoping too that you would 'shake some new info' out of the fog but maybe we already know as much as is out there.

Jerry

[Steve Little]

In an effort to stop you all falling asleep on your keyboards with boredom, we will have small deviation in the thread.
One of the Offset springers has arrived here. The customer described it as having a (bit of a crack) in the leg. His casual remark made me think it was a small crack.
Australians in the generation range of 40 and up, are know for dry wit and larrikin humour, and I think this guy can count himself in the forefront of this trend.
This bike is a known history 1947 and had a package truck attached to it, for most of its 66 year life.
The leg does not have a bit of a crack, it is completely severed between the stem crown and the spring crown.
After a close inspection I could see there was another.
The red oxide dust is a dead giveaway to any long term crack.
Springer weld repair 002.JPG
Harley Davidson would have simply scrapped this rear leg, due to the time that it will take to do a proper job in the repair.
But, they stopped making them, we will have a go at repairing it.

There is always the question of the originality virses integrity on a lot of the major parts of our decaying, old bikes.
We can blast, paint, and shine them, all we like. But the Carbon in the steel is gradually taking over as the decades pass.

I will document, what I consider to be the correct way to repair the crack and make it safe enough to ride for a bit longer.
If you feel I am going about it in the wrong manner, or giving wrong information, let us know.

All of the components that make up this rear leg are Chrome Moly.
Meaning, that the weld must be made with a Chrome Moly filler rod.
Simply butt welding it with braze filler rod would be ineffectual and most likely break the first time the bike was being primed to start it.

[c.o.]

Ouch! That's a nasty one! I'm betting nobody back in '47 would ever have thought that this was worth fixing. But like you said, "they stopped making them". I'll be staying tuned to see what you do with that one Steve.

[Jerry Wieland]

Steve I have a couple broke like that and a WLA leg that someone already tried to fix. This will be interesting. I often wondered how they could break there.

Jerry

[exeric]

That rigid leg can be bent and broken in a lot of places but that looks to be as bad as it gets. I'll be very interested to see how you go about this. I'm trying to think of how I would approach it and I'm drawing a blank.

[Steve Little]

Hi guys. The fisrt thing I did was blast the effected areas to get a better look.
Springer weld repair 006.JPGSpringer weld repair 007.JPG
I think calamity was just around the corner if this bike had been ridden much further.
Springer weld repair 008.JPG
Align it in both directions, and put the handlebar clamp on to hold the top in alingment.

[Steve Little]

Springer weld repair 010.JPG
I put three evenly spaced tack welds around the break.

[Steve Little]

I should mention, that before making the tack weld on the back of the leg, I had to take care of the brazing on the steel.
All braze material had to be removed before a steel, tack weld can be applied.
If any braze is left in the weld area it will liquefy during the weld and be drawn into the weld. As soon as the weld starts to cool, a crack will form because of the disparate nature of the two metals.

[Steve Little]

A thorough cleanup with these two tools, and the tack weld took nicely.
Note. A clean surface in this type of area is standard procedure, but will not always guarantee a good weld.
Braze can get into the pours of the metal (particularly when it is overheated).
The copper and brass will release during the heat of a weld and be drawn into a weld.
Be prepared to grind out an effected weld and do it again.
On the few occasions this has happened to me, I find that the contamination will be drawn out on the first weld and a good weld can be laid the second time.

[Jerry Wieland]

Steve

The one front end I have that is broke like that is also bent above the cross brace. I think I have to weld it first and then try and straighten it.

Jerry

[Steve Little]

Hi Jerry. Good to see your in the fray.
Can I clarify, that the leg of your springer is bent, and broken, between the stem crown and the spring crown? Can you add a picture?
Appologies if the crown terminology is a little strange. I am trying to use Harley Davidson terminology on the rigid leg components, so that we all know what part is what.

[Steve Little]

The next step was to do the weld preparation.
I selected a 3mm (1/8”) cutting blade and used it as a grinding blade.
This allowed me to make a nice tight V to a certain depth for weld preperation.
Before starting the grinding process, I measured the thickness of the leg wall and planned the depth of the V from there.
The vernia reads 0.1435, but I believe the wall thickness of the leg would be 0.140” if I scraped the rust off the inside wall, for a true reading.
The depth of my V was around 0.100” leaving a small wall thickness of 0.040”

As I laid the root run with the TIG, the remaining metal burnt away and helped form the “Back bead” of the weld and also allowed me to use less heat during the weld.

Wouldn’t it be great if I had one of those probe diagnostic tools to take a picture of the penetration on the back edge for you…..but I don’t. So you will just have to trust that I have done a good job.
TIG stands for Tungsten Inert gas. I used Argon 61 as the shielding gas and 3/32” Chrome Moly filler rods.

It is my understanding that you Northern hemisphere welders like to use Helium as the shielding gas, but it also makes a hotter weld.
How hot? I have no idea as I have never welded with it, but if it’s all you got, you could try welding faster to keep as much heat out of the fork as possible.
I kept remembering the drag racers hint while I was welding….Heat will anneal the chrome moly.....Dont listen to him, just do a good weld!!....Heat will anneal the chrome moly!!!.

[Steve Little]

This part of the repair is complete. A quick blast and coat of paint, and away she goes again with a backfire and a puff of smoke.