Frame Restoration

[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

[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.

[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.

[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

[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.

[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]

I appreciate it to Steve. I've been reading with much interest as I have a 31V with a slight reverse sweep in the left leg that will need straightening when I eventually get back to Oz and get started on it (currently in Spain until later this year at least). I don't know the measurements of it so don't know if it'll fit in your jigs but the method used should be the same. Once I pull it down I'll give it the once over with the vernier, straight edges, round bar, etc and maybe give you a call.

[exeric]

I appreciate what you're doing here Steve. I've straightened a few rigid forks and it is not easy. I used 7/16" ground drill rod in the fork stem to establish a center point, and drill rod in the rocker holes (like you have). I also made a fixture with the correct 3 hole pattern of the fork tubes and stem (same as the handlebar clamp). The only dimensions I've seen are the ones on the drawing of the rigid fork in the service manual. That drawing leaves a lot of dimensions undocumented and it makes you wonder if H-D wanted their dealers to just buy a new fork.

[Steve Little]

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 Little]

machine ream 001.JPG
I ran a 1/2" machine reamer through each of the holes with my fingers to remove any paint or burrs.
Then parted off a peice of ground 1/2" silver steel.
This 1/2" silver steel can now be used to slide through the holes and be an accurate place to measure the height of each spear with a height gauge.

[Steve Little]

I picked up the material to manufacture the hook fixture this morning. It just needs the cap heads to be machined into it and a little cleanup and some radius on the corners, and then I can have a go at doing a bit more work on the spears.

Think it will be strong enough?.
What do you think? Spear straighten fixture 001.JPG.

Chunky.

The last picture is just sitting in sittu to show approximate working position.

[Steve Little]

Not sure if this has actually been done on the forum before but here goes.
I set the 1941-46 rear leg on top of the 1936-1940 rear leg so that you can get a visual comparison.
The height gauge is only in there to support a rod in the axle hole of the top springer.
If you need me to explain the difference between the two leading edge shapes, let me know.

[Steve Little]

I had checked the springer on my 37 before starting this procedure. After putting a small straight edge on the front of the spear in my 37 I could see that the 1936-40 spear is straight. When I put a straightedge on the 1941-46 spear it has a negative curve on the front face. When I straightened this spear it looked just like the one on my bike.

[Steve Little]

Even though I have ordered the material for the new fixtures for the jig, I decided to forge ahead on this job and use the equipment I already have.
I put the jig in the 100 ton hand press and supported the end of the spear and used the breadboard nylon to try and press the spear straight.
I brought the hand wheel adjuster down onto the spear with the nylon between the end of the ram and the spear.
I used the coarse pumping leaver to do 5 pumps, and on the sixth pump there was a loud bang and a whizzing noise past my ear, followed by a thump and clatter on the wall of the workshop.
I was thinking earlier on that a piece of ˝” thick nylon would be better.
I guess my saftey warning should read DO NOT USE 1/4" thick nylon on the leading egde of these springers during press work

Straighten 36-40 springer 002.JPG
I found a piece of nylon that is 1 inch thick and put that in between the ram and the spear.
I then hid behind the mainframe of the press while I pumped the lever.
Straighten 36-40 springer 003.JPG

[Steve Little]

Interesting Dave. I know that during the straightening of the right spear I was feeling pretty nervouse. But it was only because I had no experience. Next time I will move as cautiously, but will have the experience behind me. When we do a production run of bending tubes for the frames we make, I always check the first couple off the bender. If they are a degree out we make an adjustment on the bender and continue. I then put the effected tubes over a hard wood block and give a whack with my number 4 Thor leather hyde Hammer. If I give a whack within an hour it moves easily. If I leave it half a day before giving a whack I really have to belt it to take some of the set out. This is called work hardening and it takes the carbon in the steel a few hours to gather its witts, and realise its been bossed around....but when it does, its a stubborn bugger.