Don’t use torches on portions of your machined aluminum hubs. After heat treating the alloy is age-hardened to reduce residual stresses at temperatures well below the temperature of a butane torch. Heating portions of the hub will build internal stresses back up and may increase brittleness. If you are going to use heat use an oven.
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What should I do with the heat never really got that
I put it in the oven at x degrees and then when I take it out what do I do
Also had an idea
My current bearing is 30mm od x 10mm id x 9mm long
I think the outer race is 1mm thick so maybe I could put a 638 bearing inside the outer race which is 28mm od x 8mm id x 9mm thick
Is it possible that this could work and would it cause any problems
The idea is to take advantage of the coefficient of thermal expansion of the material. Most materials grow when you heat them. Yes, if you heat an entire part the diameter of a hole through the part will increase. There are two ways you can use this to your advantage. The coefficient of thermal expansion is different for different materials - the amount they grow or shrink will be different for a given change in temperature. So you can:
- Heat the mounting part, in this case the hub, and cool the stuck part, in this case the bearing housing. The size of the hole will increase and the size of the bearing will decrease. If done correctly the bearing would fall out. However heating and cooling at the same time is obviously difficult. Try heating the entire assembly then use cold spray on the inside of the bearing housing.
- Find what material the bearing housing is made from, probably a stainless steel, and the material of the hub, probably aluminum (6061, 7050, 7075, or similar). Look up the coefficient of thermal expansion of each material (in metric units the aluminum is 20 to 24 E-6 m/m/degree C and stainless 10 to 18 E-6 m/m/degree C). In this case if you heat the hub and the housing enough the diameter of the holes will grow faster than the bearing housing and it will eventually loosen.
There are two problems with this method. The amount the parts grow/shrink is tiny and the bearing may have been press fit into a hole that was actually smaller than the bearing to begin with. Earlier attempts to remove the bearing may have scored the inside of the hole causing increased interference.
I have a bearing puller - that is the first option because it will apply force evenly and prevent damage to the hole. Next I would try the screwdriver and hammer method described above. If that didn’t work I would bake the assembly at 350 or 400 F for several hours then try the screwdriver and hammer method immediately after removing the part from the oven. Add the cold spray if that doesn’t work. Last option cut the bearing housing.
Be careful with all this stuff (hammers, extreme heat, extreme cold). A new hub isn’t worth losing a finger.
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NORMMMMM! What’s up hommie, missed ya 
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Work got completely out of control for a while. Six months of working 6 days 10 hours a day at our old factory that is 1 1/2 hours travel time from home. All I did was work, eat, sleep, and ride my production board into the ground while my build sat half finished on my work bench. I rode my board to and from the train stations for my commute. That is over and behind me. The problem was solved and we have closed the old factory. Time to get back to work on my build because the hot rod electric kick scooter I bought my wife is kicking my ass on my Evolve with fading batteries.
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The bearing puller I use is in this post.
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I can dig it, been there on occasion myself. Glad to see ya back, yell if you need an assist on your build.
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Your wife kicks your ass with an electric kick scooter? I think not.
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I meant the work schedule, but no. My wife rides like a little old lady, even on her e-bike 
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Mine has no fear and little balance. She came home with a black eye and a fat lip from a head plant a couple weeks ago. Yes she was wearing a helmet with a visor but it twisted on her head. We had to hide her for a week so the police didn’t come take me away.
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Ouch, if my wife ever face planted that would be the end of her riding. As it is I barely get her out now .
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SO BAKED AT 200C (400F) FOR 3 HOURS NOCKED WITH A HAMMER A COUPLE TIMES AND POPPPPPP
go to the whole ring out no damage at all had to bang a couple times on a couple areas of the ring but within 3 min it was out
Thanks everyone
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If I had to insert a kingpin (steel) into a baseplate (aluminum)
Interference fit
What would be the better method
- Use a press
- Put the aluminium baseplate in the oven for a couple hours? And then try
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I never held those hubs but I am curious to see what exactly you are trying to remove. Can I see a pic please?
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Who is that question directed at
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Anyone really 
If you won’t mind taking some time to do it that would be great for my curiosity.
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I was using maytech hubs will show you a pic later
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If you have access to a press I would always go simple first. If you have to use temperature put the baseplate in the oven and the kingpin in the freezer for a few hours.
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