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Gleggy on Fchat.

I made the broach support. My small endmills are all pretty dull so I was mostly beating the metal off but it worked


Then cut the end with no teeth off the broach



and got on with it.


The SS shim stock I bought to wrap the old adapter is about right for shimming the broach so the plan is get it deep enough to index well then do the rest and then start shortening the broach until its straight so like just the last 2 teeth then back to shimming to get the final depth. Its going to take a while but it seems doable.

Yesterday's plan was slow, stupid and resulted in a broken broach on the 1st cut tonight

So tonight I took a section of the broach and welded it to an shaft. I could have used a tool bit but since I'd already scrapped the broach this seems easier

Then broach the splines on the mill. About .002" per pass seemed about right and its mostly done now. The tooth profile is supposed to be a radius so tomorrow I'll grind that into the tool and finish it up, there is a few thou left to cut so it should go quick.

I like it. Broken bit? Plan B and done. I am guessing there is some heat treat coming for that parts?

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

Yes, once everything fits and loos right, the shaft goes for heat treat to RC50-52. Hopefully tonight I'll finish up the broaching and make sure it fits. Then I need to set the depth of the outer bearing, then send the shaft to a buddy who can cut the metric thread, then heat treat while I move on the fix what I assume is bent valve in #12

Got it. I like the plan. What will you need to do after heat treatment? Will you need to grind finish some of the dimensions or will it be set before heat?
Let me know if you need the valves touched up.

_________________
Wade Williams
Master Ferrari Tech
Restoration Tech
Engine Machinist
Fabricator
Racecar Driver

Yesterday was not a great day. I pulled the broach and put a little radius on


The back in the mill and cut the first, then..what the???

with a little age and dirt the 50 and 60 looks about identical


I started the second and the broach was just not cutting, I spent like 2 hours cutting 2 grooves. and I was working



Finally decide to reshape the broach tooth and 40 minutes later it was mostly fitting the trans shaft. a little clean up to get it fitting better then recut the other end.

Mostly I'm going to hope I don't need to do anything....4340 is pretty good dimensionally. But I'll check everything and polish and diamond file as needed.

I was hoping to be pulling the valves out this weekend but now that I'm remaking the shaft it might be next weekend.

Back on track. The gear fits the shaft, the shaft fits the trans shaft, the gear ends up in the drop gear case where it belongs.


Next items are the welding bugger the middle bearing fit a bit, I need to fix that. Then set up the new angular contact bearing in the cover to get a slip fit and just a little preload on the bearing set. The shaft still needs a thread I can't cut and to be heat treated so I need to ship it to a buddy once I'm done test fitting everything then to heat treater. I'll work on the the bent valves and head gasket stuff while I wait.


Oh, the 12 pt nuts came yesterday and look good. They are shiny black so hopefully that is something that doesn't just burn off

After pushing the last couple days, today I was slow. Ifigured I should confirm the shaft is sitting right and since its hollow it was as easy as measuring the drop then removing the housing and resetting the drop...perfect


I forgot to cut the locking detents in the shaft so I took care of that.

then the outer bearing needed a spacer, Its a slip fit over the shaft and light press into the bearing


Then it's more obvious where the nut goes once the thread is cut

Then fixed the idles bearing a quick test fit...working gears.

I did check the outer bearing and cover quickly and discovered the existing bearing pocket is just a touch too deep. tomorrow project.