20mm spinner bearing and press fitting

[mattsdragons]

Close to ordering the final materials for my spinner, want to find out the best bearing I should use for the disk if anyone can recommend me some good ones?

Also, how would I go about fitting them into my 20mm nylon at home? If that isn't a method I can do, what would be the next best thing?

Last question, for shafts would I be better off with Stainless Steel or Silver Steel rod?

Thanks
Matt

[maddox10]

The best bearing? The simplest bearing is a bronze bushing. Then it's a 6004 single row balbearing (need 2). The 6204 or 6304 serie are better, but need more attention to mounting flanges. Double row balbearings like the 32 or 3304 are usable.
Best are tapered roller bearings, but mounting those in nylon is just waste of time and materials.

I'm using bronze bushings on silversteel axle for Valkiri2. If bronze bushings are good enough for battleship driveshafts I think its good enough for me.

[mattsdragons]

Would drilling a hole, say 2mm smaller than the O/D of the bronze bush then heat pressing straight into the nylon be a suitable method?

[adz600]

Just use flanged bearings with pressed steel housings, light and easy to mount and can be reinforced with a back plate

[maddox10]

Would drilling a hole, say 2mm smaller than the O/D of the bronze bush then heat pressing straight into the nylon be a suitable method?

Nope, accuracy isn't good enough;

[Ellis]

Holes always drill a little small in plastics. Pick what should be the right size for the OD (assuming you're using a forstner bit or similar it should be relatively accurate) and do a test drill in the same material you're going to use, and see how the bushing fits. If it's at all loose it's a no-go, but you might get lucky and have a light pressfit, in which case you just need to devise a method of preventing the bushing from coming out (something like Gimson's old method - http://www.gimsonrobotics.co.uk/prod...ring-cover.jpg)

You'll need to make sure these holes are pretty perfectly perpendicular to the bulkheads (and in line with each other), so drilling them by hand is not really a goer. Good pilot holes etc and a pillar drill should make it doable, though it'll never be spot on.

[Max]

From my experience bushes need better alignment than ball bearings or else they jam or provide a lot of resistance. Ball bearings seem to be more tolerant to misalignment.
But I've heard other people say the opposite so I would listen to someone with more experience.

[mattsdragons]

I have access to a pillar drill or even a CNC nylon firm if the cost isnt too high, it's a shame no one makes decent bearings mounted in housings other than flanges as I would rather avoid these due to weight

[adz600]

http://simplybearings.co.uk/shop/Hou...duct_info.html

heavy ? Not by much, only pressed steel

[mattsdragons]

Those look very similar to the 2 piece housing one's I ordered from Bearingboys for Bulldog

[adz600]

Tech spec 240grams thats light for a high load bearing assembly

[mattsdragons]

May well have to buy a pair after new year, still got a few things to order for BB which is priority but will have to get some

[typhoon_driver]

haven't read much of the thread. Don't bother with bushings, terrible if you don't have the accuracy. Tapered bearings if you don't have the ability to preload them. If you don't under stand this don't bother with them. Go for ball bearings. Press fit them into your nylon, job done. Nice and cheap

[typhoon_driver]

Oh and matt when are you going to give me the tenner for that belt that i bought you before the last champs? still got it sitting now in my new garage waiting to be posted. hell i'm happy to cover the postage on it.

[mattsdragons]

Drop me your paypal and I shall do it tonight