JAk
08-06-08, 07:56 AM
Machining loose bearing hubs for fixed bearings. Is this ever possible?
JAK
JAK
Bicycle Mechanics - machining hubs
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Booger1
08-06-08, 09:34 AM
Looking at my 105 hubs,there isn't enough material to do that.
HillRider
08-06-08, 09:57 AM
Even if it could be done (and I agree with Booger1 that it probably can't) the cost would make it unattractive compared to just buying the hubs you want to begin with. Also, what's wrong with cup-and-cone bearings? They have their own advantages.
JAk
08-07-08, 05:31 AM
Even if it could be done (and I agree with Booger1 that it probably can't) the cost would make it unattractive compared to just buying the hubs you want to begin with. Also, what's wrong with cup-and-cone bearings? They have their own advantages.
I'm getting a set of little used vintage Trek 610 wheels and I thought I might find a way to do something with my old ones, perhaps just to experiment.
Yes, cup and cone is fine.
JAK
I'm getting a set of little used vintage Trek 610 wheels and I thought I might find a way to do something with my old ones, perhaps just to experiment.
Yes, cup and cone is fine.
JAK
FlatFender
08-07-08, 05:39 AM
I'm getting a set of little used vintage Trek 610 wheels and I thought I might find a way to do something with my old ones, perhaps just to experiment.
Yes, cup and cone is fine.
JAK
If you have a lathe, and know how to use it, I say give it a try!
Yes, cup and cone is fine.
JAK
If you have a lathe, and know how to use it, I say give it a try!
Booger1
08-07-08, 10:07 AM
First you'll have to get the old race out of the hub,no easy task.You can cut it out on the lathe,if you have some diamond tooling laying around.HSS/Carbide will not cut a bearing race.If you have a toolpost grinder,you can grind it out,give yourself plenty of time,because your going to be there awhile grinding them out.Then once you get it out without distroying it,remember,you only have one shot at this,then you will have to find a bearing that will fit.I don't think any of the normal bike hub bearings will work,you'll have to cut the pocket too deep and it will break through the hub on the backside of the bearing.If you can find bearings that are shallow enough,I think you can make it work.I'm sure you can find a needle bearing set that would work but then you would have to make axles/sleeve for them to ride on.
Your going to need some measuring tools that can read in 10,000ths so you can get the bearing crush correct(sealed bearing) or clearance(needle bearings).
If you use needle bearings,you'll get to practice your metallergy skills with making axles/sleeves.You'll have to make them out out material you can harden at home with a torch when your done grinding them.
If you decide to give it a try,don't forget to cut a radius in the back of the bearing bore,you don't want any stress cracks from a sharp edge.
I've been a machinist for longer than I care to remember,I'm thrifty(cheap),retired(bored) and know what I'm doing(experienced) and I still won't do it...But don't let me stop you.I've done worse things than that!!
Your going to need some measuring tools that can read in 10,000ths so you can get the bearing crush correct(sealed bearing) or clearance(needle bearings).
If you use needle bearings,you'll get to practice your metallergy skills with making axles/sleeves.You'll have to make them out out material you can harden at home with a torch when your done grinding them.
If you decide to give it a try,don't forget to cut a radius in the back of the bearing bore,you don't want any stress cracks from a sharp edge.
I've been a machinist for longer than I care to remember,I'm thrifty(cheap),retired(bored) and know what I'm doing(experienced) and I still won't do it...But don't let me stop you.I've done worse things than that!!
dwood
08-07-08, 10:52 AM
First you'll have to get the old race out of the hub,no easy task.You can cut it out on the lathe,if you have some diamond tooling laying around.HSS/Carbide will not cut a bearing race.!!
While the above statement is true . . . there is a very easy way to remove steel races from 'any' hub. No lathe or special tooling needed.
All it takes is a welder, TIG welder being the most controllable. Clean out all of the grease from the bearing and hub. Run a nice hot bead on the race surface where the balls roll. Let it cool normally. The race will shrink and you can usually turn the hub upside down and the race will fall out. This causes no damage to the hub itself.
Done it a million times!
DON
While the above statement is true . . . there is a very easy way to remove steel races from 'any' hub. No lathe or special tooling needed.
All it takes is a welder, TIG welder being the most controllable. Clean out all of the grease from the bearing and hub. Run a nice hot bead on the race surface where the balls roll. Let it cool normally. The race will shrink and you can usually turn the hub upside down and the race will fall out. This causes no damage to the hub itself.
Done it a million times!
DON
Booger1
08-07-08, 11:18 AM
Duh!!!I pull seats out of aluminum heads all day like that,good call.Doesn't work on everything,but it works most of the time.
I just took for granted that the races were shrunk into the hubs,there's not much material there,but maybe not.If it is a straight press,it will work great!It IS worth a try though,by far the best way to take them out.
I just took for granted that the races were shrunk into the hubs,there's not much material there,but maybe not.If it is a straight press,it will work great!It IS worth a try though,by far the best way to take them out.
tellyho
08-07-08, 11:32 AM
Why bother? Repack and ride.
dabac
08-07-08, 01:13 PM
Machining loose bearing hubs for fixed bearings. Is this ever possible?
JAK
Sure it is, if you've got a lathe and are stubborn enough. I've got an XT hub that nowadays takes a stock 30 mm cartridge bearing on the NDS side. As I remember it, the dia for the pressed in cup was something like 29.4, so strength wise it wasn't much of an issue with the removed material.
JAK
Sure it is, if you've got a lathe and are stubborn enough. I've got an XT hub that nowadays takes a stock 30 mm cartridge bearing on the NDS side. As I remember it, the dia for the pressed in cup was something like 29.4, so strength wise it wasn't much of an issue with the removed material.