1956 Model 99

Richard Tool said:

Forks back together. Front fender ( mudguard) dry fitted . Needs a little tweaking. Lower stay mount ears on sliders pretty well butchered in thread department by previous owner - I will likely through bolt the stays rather than try thread repair.
I turned temporary bushings of plastic for the swingarm to fit it .
I have new silent block bushes but I will install them closer to final assembly. I have the original Armstrong rear shocks but doubtful of their integrity and rebuilding them seems questionable so I purchased new Girling shrouded classic units . These come with universal bushing kits . The bushes all needed facing on the lathe in order to fit the frame and swingarm mounts .

View attachment 118244

View attachment 118245

Now awaiting return of oil tank , etc from welder to start priming of those components. Magneto and dynamo shipped off to Doug Wood for rebuilding .
Cheers ! RT

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I think the problem with the fender may be that this thread is 5/16 cycle thread and not bsf. I think original thread may have been 26tpi(cycle) and not 22tpi (bsf). This may have initially caused the problem. The former owner may have used bsf or unf thread.

I would be inclined to helicoil the fork sliders if they are not too wallowed out for the helicoil tap drill. . You can drill, tap and run in the helicoil without removing the fork from the frame and will have a stronger thread than before it was done. If there is not enough material for the cycle thread there may be for the bsf or unf thread since it has a larger major diameter.

My thoughts and can't wait to see it finished. Love these bikes.

ilikevelos said:

I think the problem with the fender may be that this thread is 5/16 cycle thread and not bsf. I think original thread may have been 26tpi(cycle) and not 22tpi (bsf). This may have initially caused the problem. The former owner may have used bsf or unf thread.

I would be inclined to helicoil the fork sliders if they are not too wallowed out for the helicoil tap drill. . You can drill, tap and run in the helicoil without removing the fork from the frame and will have a stronger thread than before it was done. If there is not enough material for the cycle thread there may be for the bsf or unf thread since it has a larger major diameter.

My thoughts and can't wait to see it finished. Love these bikes.

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The problem is someone in the past had no idea or didn’t care about the thread form and seems to have forced UNC bolts in .
Threads mostly destroyed. My rationale for through bolts is that I can use 1/4” and not have to remove any more material from the ears . I have various cycle thread helicoil sets but am reluctant to use them in this location. I think 1/4 “ is more than adequate for mudguard stays . Thanks for the thoughtful input - two heads are better than one .
I am still wrestling with my conscience regarding various fasteners on chassis components. I have several sources for BSC , BSF & Whitworth fasteners but I am on a budget with this build and can save time and $$ by using locally available stainless UNF / UNC fasteners for through bolts where thread form isn’t critical ( think Commando hodge podge) . I made up this fixture for doming the bolt heads - polished up on the buffer and turned chamfered washers will look right ( or right enough… )

Richard Tool said:

I made up this fixture for doming the bolt heads - polished up on the buffer and turned chamfered washers will look right ( or right enough… )

https://www.accessnorton.com/attachments/3gfiob-webp.73373/

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Love the radiusing jig! I've got one for my lathe, but most often just put the bolt in a drill and hold it against the belt sander.

looks great. Moving right along!

Pre Commando I do not believe Norton used BSF much mostly I have found most cycle parts were BSC

Some more progress - as the motorcycle moves forward the bank account goes in the other direction.
Oil tank primed , glazed with Upol , sanded and primed again -


Main rear mudguard section primed and glazed -

Tip section primed , glazed , blocked and primed again -

Headlamp primed , glazed , blocked and primed again -

Fuel tank paint stripped to reveal a few dents - must have gotten into a tank slapper at some point . Looks like another cut open and bang out project . These tanks in 1956 were chrome with painted panels - I would like to do the same so that means body solder - no plastic filler. Even if I am successful in removing the dents it may be cost prohibitive. If that’s the case then I’ll go for the later style painted tank with screw on chrome side panels - we’ll see…

Thanks for looking.
RT

@Richard Tool Sorry about your bank account, but the pain looks like it will be worth it, emotionally anyways.

seanalex said:

@Richard Tool Sorry about your bank account, but the pain looks like it will be worth it, emotionally anyways.

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Thanks Sean - I sent you a PM a while ago - did you get it ?