trying to shed some weight

[Eldert]

i did some drilling , milling and turning on the selectordrum and the shafts the selectorforks slide on this week

total weight saved 520 gram or more then a pound





i did some work on the bottom bevelgear to






Eldert

[Jordan]

Nice work.
Is it difficult to machine? Special cutting tools?

Jordan

[Eldert]

Hi Jordan

the drum is very hard to machine . what i did is i send the drum to a place to have it softened and then did
all the machining . when this was al done i send it to the same place to harden it again ( nitrating )

the selectorfork shafts i drilled with hard tipped concrete drills

Eldert

[Rick]

Well there's some dedication to weight reduction.
Are the parts 'through' hardened from the factory, or a surface or 'case' hardening? I would have worried that the annealing, removing material, and rehardening would have introduced some distortion- do the dimensions remain stable through all of this? Did you mean nitriding to restore the surface hardness? My only experience is in heat treating high carbon tool steels that require some precision grinding after the heat treating to hit a target dimension, but I talked to a guy who was setting up to do 'gas nitriding', a surface only hardening, that he claimed was done at low temperatures and less likely to cause distortion, but things changed and I never got a chance to send anything to him.
It's good to see people making little improvements that would have cost too much for the factory to do.
Rick

[wcorey]

...'gas nitriding', a surface only hardening, that he claimed was done at low temperatures and less likely to cause distortion,

I think it's 'plasma ion nitriding' that doesn't require temps high enough to cause distortion...


Bill

[Rick]

I Googled plasma ion nitriding, and found a place in the midwest that does it:
http://www.mtvac.com/pages/plasma_nitriding.html
They say there's no distortion and it even increases tensile strength. Looks good.
Rick