Gear cutters?

[TimK]

Do any of our Australian members know of a gear cutter in NSW that may be able to help me with some gears for a Sturmey Archer gearbox for my 1929 AJS 350
Cheers
Tim K

[jimmy]

G`day Tim not nsw but i used an engineering firm in Euroa Vic to cut and harden gears for a `27 triumph, regards Jim

[TimK]

Thanks Jim, our daughter lives in Melbourne so Euroa is an easy stop when we travel down to see her. Was the company you used Ford McKernan Engineering? I did a search for engineering firms in Euroa, and their advertising includes gear cutting.
Cheers
Tim

[BSA_54A10]

If you are coming the the BSA National Rally next week in Gloucester then have a chat to Doug Frazer who is coming on the B66
If not give him a call early next week at Emu Engineering
I don't think they cut gears but fairly sur he has had several cut .

[jimmy]

G`day Tim, yes Ford McKernan Engineering did a good job for me, regards Jim

[TimK]

I've managed to find some stock DP10 Spur gears on-line that I should be able to modify to fit the shaft. The material is S45C - does anyone know if this can be heat treated successfully?

[BSA_54A10]

S45 is 0.45% carbon steel so does heat treat, it will flame harden as is and can be cased with caution, if deeper harening is required
it is basically the same as AISI  1045 steel but with a much higer & wider band of acceptiable impurities.
Basically it is a downgraded 1045
Most of the Asian JIS standards are the same as AISI ones but with higher impurities so they can be made from scrap remelt and still be within specifications without the need to purify or dilute the impurities to AISI levels.
It is becoming a big problem for steel industries world wide as more & more Asian steels saturate the market
China runs it's own standards that are even more dirty
Because of the high impuritiy levels it can not be nitrided ( in any form ) or cryogenically heat treated ,
It can not be through hardened either 
Aussie sort of equivalent is 1045 under AS 1442  and is heat treated the same .

[TimK]

That's really useful information thanks. The alternatives to using these stock spur gears is to either have some gears custom made,  or there was a complete compatible gearbox on ebay for A$1250! If I can use these stock gears I can get the job done for A$400 so it's got to be worth a go - especially as the bike is never going to be used hard. I'll let you know how I get on.

[chaterlea25]

Hi Tim,
I know the UK is a long way from NZ, but HPC gears will supply gears in EN24 or special order in EN36

https://www.hpcgears.com/

John

[jimmy]

Hello Tim, a`29 AJS has its own make gearbox not a Sturmey Archer. AJS gearboxes have a crash second gear, which is its weak spot and why they went to S.A. in1930, also the gears in 1929 have stub teeth which are stronger. I have a 1929 M8 and had to get a counter shaft made regards Jim

[TimK]

Hi Tim,
I know the UK is a long way from NZ, but HPC gears will supply gears in EN24 or special order in EN36

https://www.hpcgears.com/

John

Thanks John
EN24 would be a good option as compared to S45C it's well known in Australia. I'll check out their website.
Cheers
Tim

[TimK]

Hello Tim, a`29 AJS has its own make gearbox not a Sturmey Archer. AJS gearboxes have a crash second gear, which is its weak spot and why they went to S.A. in1930, also the gears in 1929 have stub teeth which are stronger. I have a 1929 M8 and had to get a counter shaft made regards Jim

Hi Jimmy
I spent ages scratching my head trying to work out why my gearbox was similar, but not the same, as the 'other' SA gearboxes. My gearbox certainly has a crash second gear on which the individual teeth are now triangular due to wear. There was a complete AJS OHV gearbox on ebay last week but at A$1250 it was too expensive as I only need the gears. I think I'll be checking out the website that John recommended (above).
Cheers
Tim