the bearing that she is banging in is bigger than the motor will be using and I fear if she uses the correct thinner bearing it will be crushed or too tight as Mr.happy says. but I’m not sure it will be too tight so asking her to try to press the right bearing in with the big one she showed on top and using a true press and not a hammer. If she can get the right bearing down there without crushing it then it’s good as is and we get things five days sooner! I have bearings with internal clearance within them for just such a tight fit anyway.
Id rather it be a press fit actually but it looks way too tight in that video. We will see.
I don’t mean to say that you are doing this wrong, but shouldn’t the bearing be inserted using a hydraulic press(or mechanical). That way it gets uniform pressure from all sides. I would suggest a car jack installed in such a way that it can push the bearings in.
Also you might have to heat the outer one and cool the inner one
A good fit is desirable for long lasting operation
for sure agree with both of you. ive asked her to try again pressing the 52x40x7 bearing under the monster bearing she’s banging in with the hammer. I have no idea what goes on at that place considering. maybe its a good test. for me getting an appropriately sized bearing with what would amount to something like .005mm interference ideally is rare and expensive to find. . Retaining fluid is often recommended. But woke up at 5am and told her to NOT cut them all (hopefully!) to the wider 52.00 with tolerance +.02 that was what it was supposed to be. So I want an interference fit, and I want it on the housing side first and possibly even the shaft with the obstacle then being assembling: pressing the two bearings at the same time, so pressing the stator into the rotor yea I’d like to get some liquid nitrogen and shrink them solid and working that way but given having put together the old the retaining fluid is pretty versatile though and as long as not too hot it lasts. a squirt on interference fit and the ultimate in smooth silence. but some people ride bare with the tight slide fit even on the aluminum motors and the rattle is pretty minor. interesting to see no one told me of their aluminum shaft being worn down and I’m still riding the oldest blue goo aluminum just to try to kill them and the shafts haven’t shown to wear while riding( I don’t open them to look because that design sucks to open and close, more glue and huge effort sometimes.) I guessed the cheap 6000 aluminum would’ve worn down but don’t know the forces that would be on that 20mm x 7mm aluminum shaft. Doing 30mph with a 200lbs rider on a mediocre road and than smacking a pot hole or something, can you guess/math the forces or maybe put a sensor on something?
steel now though buddies and syched.
(the shafts on the sample were a tight press fit and its a wild ride getting these parts made at a reasonable price even with the supposed to be tolerance of -.02mm .)
I know, i work as a machinist in a printing press machine shop for summers. its constant bearing swaps for all of the rollers. He asked what the dangers of a bearing fit being too tight.
it will be close to 2018 new year day I think. definitely no later than January. they just are doing the last bell and say it takes an hour to machine each one. so they say. they always pull through just slowly.
give me till a couple days into January and I really think for sure as the latest. they’re on it now they say. ok they just said about 15 days. I know it seems like that all the time but its out of their mouth and lets see where we are in a week and confirm
but she says she can get me a couple beginning next week probably without any finish. I’ll do the “seasoning” thing as I was planning to do before and wrote about. if that sounds good to you and you don’t feel like waiting another week and a bit for them to put a clearcoat pm me and I’ll get some more this way.
No stress my friend. Take your time and make them right. I don’t want a half baked product. In that case I wold buy maytech or other Chinese hubs instead.
If I get them 1 of march I’ll be a happy guy. Then I have a month before snow melts to make my build ready.
I sub for the san Francisco school district and do it all from elementary to principal. I mostly babysit special ed “emotionally disturbed” middle schoolers or work with the high school kids who got kicked out of their regular public school for something and corralled all to one location.
but it’s not hard to put a finish on these bare steel parts and don’t think I could fuck it up.
Gold plating wouldn’t be much harder and just need to get a copper layer on first for adhesion.
cant fuck it up too much and worst case would sand it down and do something else
Monday. She says Monday and I believe her. all of them sent then. she’ll send me some video of the two bearings in and other shots to show its all good first. so just bluing of the stainless nut in the middle and small flange screws. the rest will come with a finish.
these 4 are being sent today and will be here in three days. the rest they say will be a couple more days as theyre cleaning up some burs from machining.
but simple and surely good enough and rather not be heating the steel so much it’s hardened. (edit…don’t think the mild steel will harden having so little carbon and the simple hot method is calling to me 