Frame Restoration

[Steve Little]

Run out of time today. Will post pictures of deck cutting tomorrow.

[Steve Little]

Cutting the decks.

When a frame has been welded or brazed there will always be contraction at play.
Contraction is the pulling force of a weld as it cools.
A 6mm or 1/4” fillet weld in a corner has a contraction rate measured in Tons.
During the welding of a frame, contraction can be managed to a certain point, by balancing the welds across a frame.
This means, don’t weld everything down one side of the frame and then weld everything down the other side.

During the welding of the engine mounts, the contraction pulls at the decks.
The rear decks usually (but not always) pulls up which decreases the important angle to the seat post and also increases the gap from the front engine mount.
The relationship of the seat post to the rear deck is important because it dictates how close the rear head will be to the seat post. Harley Davidson designed this angle to be 74 degrees and 4 minutes.
The measurement from the rear deck, down to the front engine mount is 1.625” for frames 1936-1947 and 2” for 1948 through all Pans etc.
When we have checked a frame and determined that the decks need cutting, we bolt it into the jig on one of our mill and then take a very light witness cut across the rear deck. The witness cut shows any distortion. We then evaluate the next cut on what we read from this.
Enjoy the pictures of young Steve weaving some magic.
1945-46 frame restoration 001.JPG

1945-46 frame restoration 004.JPG

1945-46 frame restoration 008.JPG

1945-46 frame restoration 007.JPG

28 hours and Job is complete.
Hope it was informative.

[exeric]

It's amazing how you found a milling machine that is purpose made to deck Harley Davidson motor mounts In all my years in machine shops, I've never seen a mill with such a low profile head and I can think of many jobs where that would have been a life saver. Steve, thank you so much for taking the time, and making the effort to document the remarkable work you do for so many people. You are a true craftsman.

[Steve Little]

Hi Eric.
I appreciate your praise.
It felt like, it took as long to enter the thread posts as it did to restore the frame.

I originally had a Deckel FP1 for this job. Deckel is a world renowned (German made) toolroom mill, and they are very sought after.
If you use a Deckel, a new (shorter) quill has to be manufactured to get into the deck area. This means sacrificing the manual drill operation of the head.

It was a great machine but a little light for the work, so I traded it in when I bought our CNC mill and then bought this current machine which was manufactured in 1957.
I knew this machine would fit in with out alteration. This machine is solid and handles this job, and other jobs with ease.
Thanks again.
Regards Steve

[DANPATCH]

Steve how do you tell the differance between the 1936-1940 springer

[Robert Luland]

Grease nipples are inboard on early and out board on later. There are other differances but at a fast need to know glance, etc. Bob L

[Steve Little]

The rear leg of 1936-1940 springers have a forward sweep in them.
The 1941- early 1946 are a ( true) inline springer. If you stand back and look at a foreword sweep you will see it.

[koanes]

I have been curious about the "Forward Sweep" Is there any factory documentation in the form of a blueprint, drawing or repair manual instuction? The common Knuck/Flat repair manual only shows instuction for checking the fork with a rod through the stem hole aligning with the rocker stud holes. I have seen early NOS forks that do not show curve. Does anyone have a spec for the forward sweep?

[exeric]

I've had 3 or 4 early forks and they all had the forward cant or sweep. I recall seeing a drawing Steve Little posted of the dimensions he has documented. Oddly enough, I never noticed it until Peter Reeves pointed it out to me. So much for my powers of observation.

[DANPATCH]

Bull neck frame

What was the serial number for the Bull Neck frame Thanks Steve

[Steve Little]

I have been curious about the "Forward Sweep" Is there any factory documentation in the form of a blueprint, drawing or repair manual instuction? The common Knuck/Flat repair manual only shows instuction for checking the fork with a rod through the stem hole aligning with the rocker stud holes. I have seen early NOS forks that do not show curve. Does anyone have a spec for the forward sweep?

Kyle. You have PM.

[Steve Little]

Hi. We are about to start a new frame restoration, and I thought it would compliment the information of the restoration we did last year.
This is mostly, a front half restoration so we will be brazing on a neck and fitting sidecar loops etc.
After a couple of phone discussions on procedures, the owner decided he had the skills to pull the frame apart but after doing this, he decided, he did not have the proper equipment/jig to ensure the correct alignment during re assembly.
He has done a good job of disassembling the frame and the following shots show where this frame has suffered at the hands of the demon chopper guys at some time in the past.
The owner wants the frame restored to original specs, and I will document the repair and re-assembly of the frame as we proceed.

[exeric]

Looking forward to it Steve. I always learn a lot from your knowledgable experience, and well researched observations.

[Steve Little]

The seat post cluster has been severely modified during the frame’s chopper stage.
My guess is that, the top half of the backbone spigot, backbone and the top section of the seat post cluster has been cut off to achieve a flat surface for the base of a chopper seat or a metal plate could be welded to this section so that body filler could be smeared over the area for the sanitary look that was favoured at the time.

Whoever has tried to recover this frame for the re-assembly of the bike, has welded a piece of seat post tube to the top of the cluster to support the piece of seat post bush that would have been sticking out of the top.
The tube looked odd without the casting around it so we have removed the bush and cut the extension tube off.

[Steve Little]

I knurled a piece of tube and cut out a section to repair the missing piece of the spigot. I put a nice V on each end of the repair piece for weld penetration, and then slipped a piece on 1 ˝ tube over the snout of the spigot to hold it in place while I tacked it in place with the TIG welder.
Appologies for the picture quality. The old shop camera is not the best...and to be truthful, even with my glasses on, I cant tell if its a good picture in the view screen until I load it up to the laptop.