Press Fit

[DELurker]

All of your bearing fit information (radial ball) can be found in the chart on page 131 at http://catalog.timken.com/WebProject...ookcode=eng11#, with the codes defined on pages 132-145.

If you can't make the holes to the specifications listed there, 0.001" undersized should work. I've found that Loctite Retaining Compound 641 works well in other applications, if you want to make the hole right at the bearing diameter.

As for press fits into thinner materials, I would recommend a flanged or snap-ring bearing with either retaining compound under the lip or 3 screws at 120-degree intervals.

[MrForbes]

fwiw, we made a couple gear boxes this year using flanged bearings and polycarbonate side plates, we discovered that drilling a hole with a Forstner bit will provide a sufficient press fit. There are lots of ways to do things like this.

[pmangels17]

Also note that polycarb cracks when you put loctite on it.

[AdamHeard]

This is an area where standardizing in design can make things a lot easier. If you only use a few common sizes of bearings, then you can get the appropriate reamers for these bearings (at some expense, but not awful; and due to design standardization they're used almost everywhere on the robot).

We have a press fit and slip fit (press being .0005 to .001 under depending on the availability of the reamers) for most bearings and bushings we use.

Most 973 robots over the past few years have most gearing running on plates that were waterjetted then reamed out by a reamer in a hand drill.

The reamer is really the best compromise between precision and the ability to use it on any given part and machine. It also allows "fixing" of damaged or out of tolerance parts.

Originally Posted by squirrel

fwiw, we made a couple gear boxes this year using flanged bearings and polycarbonate side plates, we discovered that drilling a hole with a Forstner bit will provide a sufficient press fit. There are lots of ways to do things like this.

Materials like polycarbonate that are much softer/weaker than the bearing itself will allow a much greater range of bore sizes without undue damage to or efficiency loss in the bearing.