8mm pinions
 

Any view on where / if these can be obtained? thanks

www.sdp-si.com has some

I'm guessing you're trying to see if one of the 1521's on the Neu specials page is a worthy purchase?

if you get in touch with Kershaw Designs he might be able to make you some, I was planning on a 8mm 1521 for a boat

Only problem is finding a source of hardened 8mm bore mod1 pinions... I doubt plastic spurs will last too long with a 1521.

if you can find some non hardned steel pinions you could harden them yourself

There was a thread about that on here, right? Where you get the steel super hot and dunk it in some hardening compound. If that's what you're referring to, I can imagine that coating would wear off considering the power level, after enough usage. Or am I wrong?

Hardeneing is interesting. Some metals are compounded to allow for hardening by heating and air quenching, while others are to be quenched by oil dunking. It basically rearranges the orientation of the metal on a molecular level...

I have had decent success annealing certain hardened pinions and the rehardening them, these were the top gears in the old emaxx tranny. I wanted to drill and tap them for set screws, and that would be nearly impossible as they are hardened.

The best bet would be to buy the spi pinions and try to harden them. Spi should be able to give you material spec, and someone in the know would be able to tell you how hot to heat them to, how long to keep them hot and how to cool them. Might take a bit of seaching, but there are tables setup for various metals. I may have them somewhere, I will have to look.

When working with steel, the quicker you cool it, the harder it becomes.
To harden most steel it is heated to a medium red or slightly above the point where it becomes non-magnetic. It is then quenched in water, oil or air depending on the type of steel. The steel is now at its maximum hardness but is very brittle.

Here's a 20 Tooth. How many tooth were you looking for?

http://cgi.ebay.com/Steel-Metric-Spu...2em118Q2el1247

kershaw designs made me a hardened 8mm bore with a reducer sleeve to use with 6mm shaft... it cost around $30 though for a 24T

I'm not sure I was eying up the 1521 Neu's on special but they all had the 8mm shafts

Just wondering what the options were... I don't really have any thing for it to go in but tempting never the less.

That's a damn good price. Only problem is a lack of being hardened.

SDP-SI has the 8mm shaft out of Carbon Steel and it should be strong enough.

only problem with the SDP-SI gears, are the size of the set screws... they are super small...