I think that would worry me even more with shattering.

 

seriously though I think a case hardened annealed alloy would be good for wear and durability both.

 

The metal is really gonna be the cheapest part of this, so I think we should splurge and get a non heat treated 28C alloy. I cant remember the name of it though. Easy as sin to machine and since its not heat treated you dont get some of the nasty effects

 

you heat treat after machining... to remove machining induced stress and then harden the outer skin to prevent wear but still maintaining the overall ductility.

 

**** heat treating theres no reason for it. And since most heat treat places add more carbon than I would want in my gears

 

how about if I stick them up your butt for 20 minutes.

 

Yeah but then how do we quench em?

 

Pee?

 

i follow. Alright lets do this thing

 

awesome.

not many threads can go from metallurgy to scatalogy.

 

loki&y8s+1 cup=treated gears

 

been reading up on here and the associated links there, seems they went from using treated stainless to billet...now I have already shown how much I know about alloys, but what is the difference here...they also mention hardness to be Rockwell C 48-52 or something like that, so brittleness seems not to be the issue if the gears are hard enough.
My other concern is, how do I drop these in, supposedy I can just buy a new pump and drop them in, I have to have the pump machined to fit the gears to get the best oil pressure. Anyone know of a step-by-step for this or do I just go to local shop and open my butthole?

 

You suck at links. They are doing over kill with the 48-52. 25-29 is still going to be way too hard for our needs. They are just raping you.

Stainless is a bad idea in these kinds of situations.

 

Expansion?

 

Lol, billet means a piece of wood or metal Dan. A piece of steel will work and do fine.

 

You are thinking of brake die. Generally 29-32 Rc. It would work fine without any case hardening. One other thought now that I have actually seen these gears is to use A2 tools steel without heat treating. Good toughness and hard enough, plus not really any more expensive than brake die but available in more sizes.

 

Yeah according to dictionary.com, but really its used to describe the the process. FOr example the stock gears are not billet but the new gears will be billet

 

I did a quickie look on mcmaster and saw the tool steels and they looked interesting. something like an S7 may also be noteworthy. designed for repeated high impacts and wear. sounds interesting. HRB 95ish.

is brake die just a high-carbon chromoly?

 

Drawings are done and will be scanned and emailed to y8s Monday. Jordan, PM me your email address so I can send them to you, too.

y8s, S7 world work fine as well. Back when I used to work for a living, we used to use A2 and S7 for all of the forming die components due to its toughness, whereas D2 would hold a better edge for punches and dies with less impact resistance.

One nice thing that I found when measuring the parts is the outer gear is .372" thick and the inner gear is .485" thick. Makes it nice to make from plate which will be .375" and .500" thick. Less machining means less built-in stress. I debated on plate vs bar, but with the quantities talked about here and the nominal thickness of the parts, plate will likely be the way to go. Both S7 and A2 will be available in preground thicknesses. Finish the thickness, mill around the boss on the inner gear, stack them up and wire EDM the gear profile = completed gears.

 

awesome john.

I think when bill made them he used slices of round stock that was bigger than the outer gear. plate's probably easier to purchase in moderate qty anyway.

hey i was going to ask you but didn't cuz you left for the weekend... do you guys do precision grinding of flat surfaces, say, for rolling ball bearings on?