Milling Rite

[Dave Bonzo]

I used to work in the bearing industry, I make this statement on just about every bearing thread, counterfeiting is rampant with bearings, even though you will pay through the nose, it is best to buy from an authorized distributor to make sure you are getting an authentic bearing. You might be safer with inch series bearings since those are not usually made overseas, but it is prudent to be careful about where you buy them.

Thank you for that warning. I wouldn't have thought that bearings were a heavily-faked thing.

I used a couple screw drivers to pry it off, mine was not on too hard, but wouldn’t come off without some persuading. That area is aluminum, so you want to be careful when prying it off and just do a little bit at a time.

I was thinking about some plastic wedges, or something similar.

 

[Ischgl99]

Thank you for that warning. I wouldn't have thought that bearings were a heavily-faked thing.

I left the bearing industry in 2009, at that time it was about 10% worldwide. All the bearing companies have departments whose sole job is to hunt down fakes and shut them down. FAG raided a distributor in Europe and found a bearing with about a 500mm bore was counterfeit, so it’s not limited to smaller commodity bearings. Dubai is a free trade zone, so many bearings come from China unmarked, get offloaded, counterfeited, and then shipped further on. The sales manager from Dubai did a presentation at one of our sales meetings and said he lost almost all his business in the region to counterfeits. His customers knew they were counterfeit, but bought them anyways because they were so cheap, The ironic part is, the customers still wanted him to help them troubleshoot problems with the counterfeit bearings knowing they were fake because they had the FAG brand!

 

[RaisedByWolves]

I bought some for an engine I am building, and the plans specified their gears since the designer lives in Germany. The quality looks really good, I haven’t actually used them yet, but they appear to be as good as anything else I have used. The only thing I don’t like about Maedler, their product selection page does not work on my iPad and I need to go upstairs to use the desktop. First world problems.

I was going to mention their page layout was ****.

 

[RaisedByWolves]

Thank you for that warning. I wouldn't have thought that bearings were a heavily-faked thing.



I was thinking about some plastic wedges, or something similar.

I’d recommend the type of wedges used for drill chuck removal. You may have to make them custom to fit your needs but this would be the safest bet.

 

[RaisedByWolves]

I don't have a press, so that's gonna be a problem...but I can probably figure something out. Time to look up part numbers.

No press could be an issue and all I can say is…



Do not, don’t, don’t not …hammer on the inner race to extract or install any bearing you plan on reusing.

Even with a press this could cause issues putting flat spots on the balls or races.

A bearing tool is simple enough to make even if you are only going to use it once.

 

[Dave Bonzo]

I’d recommend the type of wedges used for drill chuck removal. You may have to make them custom to fit your needs but this would be the safest bet.

The irony of that task's simplicity given a working mill is not lost on me. If I had a smidge more room underneath the pulley, matched pairs of cheap wooden wedges would work great.

No press could be an issue...

I've been looking for a decent, used arbor press for months, and for exactly this kind of reason: if you have to futz around with a bearing, they're just so very handy.

Do not, don’t, don’t not …hammer on the inner race to extract or install any bearing you plan on reusing.

Having transcended my ape-like upbringing and entered the Anthropocene, I hope to avoid this.

Even with a press this could cause issues putting flat spots on the balls or races.

A bearing tool is simple enough to make even if you are only going to use it once.

I haven't done a lot with bearings, but I've usually been able to press them smoothly into an object, or press a shaft out from around them...but in my picoshop™ there's no room for a large press. Hell, I don't even have space for an extra-medium one... otherwise I'd just get a 10-ton from Hobo Freight and then worry about the bearing situation more than the force-applicator. Thus, my search for an arbor press that's large enough to be useful but also small enough to not take up too much space. I'd also thought about slicing down one of the HF models to either fit on a benchtop or tuck into a corner, but that didn't seem ideal so I didn't do it...mostly because the only corner I have is really small, and because my benchtop is still three discrete pieces of wood, because my jack and jointer planes and all of the clamps are still an entire First-World country away.

 

[Ischgl99]

I wouldn’t mess with the spindle bearings unless you know they are bad. It’s easy enough to take the quill out, so I would start with the upper two bearings. If that solves, you’re done, if not, you can take it apart again easily enough.

When putting the bearings back on, it is best to heat them up. Since none of them have seals, you can heat them on a hot plate making sure you use a low setting, the bearings should not be heated at any point above about 250F, but I limit that to about 220F to ensure they are not overheated. if you go hotter than that, you’ll start taking hardness out of the bearing.

 

[Dave Bonzo]

I wouldn’t mess with the spindle bearings unless you know they are bad. It’s easy enough to take the quill out, so I would start with the upper two bearings. If that solves, you’re done, if not, you can take it apart again easily enough.

I was only planning on looking into that pulley bearing, at this point; I was assuming that it needed to be pressed out.

When putting the bearings back on, it is best to heat them up. Since none of them have seals, you can heat them on a hot plate making sure you use a low setting, the bearings should not be heated at any point above about 250F, but I limit that to about 220F to ensure they are not overheated. if you go hotter than that, you’ll start taking hardness out of the bearing.

I don't have a hot plate, but I can pop them in the oven for a few.

Note to self: a small lab oven would yet again be really convenient.

 

[Ischgl99]

I was only planning on looking into that pulley bearing, at this point; I was assuming that it needed to be pressed out.

Yes, that bearing will get pressed off the pulley shaft. If you heat up the new bearing, it will go on nice and easy. You can press it on, but that wears away a seat slightly each time, so over time, that fit could become loose, and there is a risk of pushing a burr against the shoulder, preventing it from seating properly.

An old toaster oven would work well for heating up the bearings. I use my multimeter with a temperature sensor to see when it is hot enough, I don’t like the heat crayons on things like bearings.

 

[Dave Bonzo]

Yes, that bearing will get pressed off the pulley shaft. If you heat up the new bearing, it will go on nice and easy. You can press it on, but that wears away a seat slightly each time, so over time, that fit could become loose, and there is a risk of pushing a burr against the shoulder, preventing it from seating properly.

I looked at presses again just a minute ago, and it's - ...wait for it... - depressing to see how expensive they are. Without starting a debate, I can see why Chinese imports have taken over the market: they may only have 75% of the quality and 50% of the fit/finish of US-made options, but they offer 95% of the capacity at 20% of the price...and that's hard to ignore. $1300 for a 3-ton Dake ratchet vs. $250 and free shipping for a Vevor isn't even a comparison...and sure, it's not an equal comparison between quality, either, but the bearing being pressed off doesn't know that. I'm kind of tempted to get one and just tune/fix/modify until it works well; I can probably accomplish that for less than $1000.

An old toaster oven would work well for heating up the bearings. I use my multimeter with a temperature sensor to see when it is hot enough, I don’t like the heat crayons on things like bearings.

I thought about surplus lab ovens just because of temperature stability; I used to do that exact thing with the toaster oven and a temp probe, but I got such unpredictable results and screw-ups (mostly with paints and coatings and stuffs) that I literally executed my toaster oven via firing squad. Might just have been that oven that sucked so much, or it might have been just me...but I thought that if I could find a countertop/shelf model, if might do well for me.