lotus 30
classic car enthusiast mostly lotus
- Messages
- 684
- Location
- caldicot south wales uk
I see you have read my first post LOLIf the originals have oil ways your replacements will also need them
Ahh sorry, I see i have re-arranged 2 words in my head when I read it , maybe I've caught dyslexiaI see you have read my first post LOL
The middle bit is cut away for the pinch bolt to hold it all down on the head so it does not move will post another picture that is best remember we are talking a toy so not a great milage involved and easy to change.The material you choose is very much linked to the heat treatment process you choose and also the grinding after heat treatment.
The semi-circular notch in the centre could exacerbate distortion if you do a home-treatment (heat up with a torch and chuck in water or oil). There are a limited number of steels that are simple to heat treat at home. If the heat treatment is likely to lead to distortion, the unhardened part will need a greater finishing allowance.
If you go for commercial heat treatment, there are lots of options (e.g. nitriding) which can have less effect on part geometry (and thus might only need lapping after HT). But the steels best suited for nitriding are not necessarily the same as the heat and quench ones.
In making the part, you need to consider how you will hold it to grind it - it may need to be a lot longer and then the excess cut off as a last operation when the geometry is correct.
Would it be correct to say that the centre section does not move or have something move on it? If so, does that part need to be hardened? Some of the old books on case hardening describe how you can impregnate the whole part with carbon and then machine away the bit you do not want to be hardened before selectively hardening what remains.
Good shout. That's not gonna be an easy thing to holdHolding them for grinding might be tricky but there will always be a way. Also if the shafts are hard and worn then the rockers will be worn too.
I'd put a file on them first and see how hard they actually are, or aren't.