Filling in Splines

[Carl Wilson]

I've been watching AG Engineering on YouTube. If you haven't seen him, give him a watch, well worth it.

He's been rebuilding a BSA crankcase with different bearings. As part of this he has a crank that needs the splines modifying. He's talking about building up the splines until solid and then remachining them.

The question I have is how you'd go about this. Tig brazing or welding? What filler etc? I'm not asking on his behalf, this is purely to satisfy my own curiosity. And I know there are a lot of experienced people here.

 

[8ob]

If the crank is a forging you could arc,mig or tig it. If its cast steel it will also weld.

Bob

 

[ronan]

The BSA B and M -series singles crankshafts were not the best, even the fabled Goldstar gave crank trouble. It was down to both design and material. I cannot remember what steel they used, but i reckon welding on it could be trouble. Why does he want to fill in the splines anyway ?

 

[Gritineye]

I repaired some clutch shaft splines using brass dams ( three pin plug earth pins) in the groves and MIGed against them, turned it all down in the lathe, good enough for a country job!

 

[chris pruteanu]

I weld new bearing surfaces on cranks with sterlite, it's hard to machine due to high rockwell strength but it's durable. I build loads of pinions, cranks, drive shafts, etc this way...

 

[Carl Wilson]

The reason he wants to do this is because it isn't the right crank and he wants to see if it's possible to modify it to work. It's probably best to watch his video as he explains it much better than me.

 

[ronan]

The reason he wants to do this is because it isn't the right crank and he wants to see if it's possible to modify it to work. It's probably best to watch his video as he explains it much better than me.

I see, there was a bit of crank-swapping used to go on with old British bikes for various reasons. I have a Triumph engine with a Norton Commando crank in it. M20/21 sidevalve cranks used to be put into b33's, gave a good increase in capacity.

 

[Carl Wilson]

Well what he is doing is putting needle roller bearings into a BSA crankcase, which involves boring out the original registers and re-routing the oil ways by drilling. I'm not au fait with the ins and outs of British bikes (that's my brothers area) but I'm very interested in any sort of engineering.

Also I'm supporting British you tube engineering channels. I don't watch the Americans anymore.

 

[ronan]

Well what he is doing is putting needle roller bearings into a BSA crankcase, which involves boring out the original registers and re-routing the oil ways by drilling. I'm not au fait with the ins and outs of British bikes (that's my brothers area) but I'm very interested in any sort of engineering.

Also I'm supporting British you tube engineering channels. I don't watch the Americans anymore.

Yes i have done this on my A10, the end feed conversion its called. No welding on the crank though.

I wouldn't ignore the American youtubers, they are good craftsmen.

 

[Carl Wilson]

It isn't the craftsmanship that concerns me. It is the constant product placement and begging for money. I cant abide it.