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.RC.
09-22-2011, 07:34 AM
Long story.. Had a Metabo drill die, electronic speed control died...second time it happened, costs nearly as much as a new one to repair....

So I say stuff it and buy an elcheapo 1000W electric drill... First one drills 18 holes (hammer drill, 12mm holes in concrete) then dies.... Take back for a replacement..

Next one screws in 80 batten screws and the chuck stops turning and makes slipping gear type noises..

Pull it apart and a bearing that holds the reduction gear in position has died....

I am going to replace it with a plain bearing and have some brass rod to make it out of on hand.... But I know bearings are usually made out of bronze...

Would brass work OK in this appilcation.... Seen a lot of brass/bronze bearings used before in hand tool reduction gearing applications...

moe1942
09-22-2011, 09:57 AM
If you want a sleeve bearing this is the material you need.


http://mdmetric.com/b1.pdf

Why not go back with a quality sealed ball bearing??

Dr Stan
09-22-2011, 10:05 AM
Brass will simply seize as it cannot hold lubricants. A plain bearing, AKA bushing, needs to be made from sintered bronze since it is porous and can hold grease and oil.

Toolguy
09-22-2011, 10:13 AM
You need a hard bronze bush like aluminum bronze for that application. Brass is too soft. The sintered oil impregnated bronze, sometimes referred to as Oilite Bronze is too soft too. The material itself may be OK, but being porous it is easily hammered out of shape. Most likely there isn't room for a steel ball bearing which would be the best of all if you could find one that will fit.

Scottike
09-22-2011, 10:22 AM
If it were me, I'd go with SAE 660 bearing bronze, or a replacement bearing - the bearing would be cheaper and should be easy to find.

ironnut
09-22-2011, 10:28 AM
I agree with the previous poster that brass is not a good bearing material, 660 bronze would be a much better choice especially if a reservoir of grease or oil is present. The sintered bronze (oil impregnated) bearing would be a better choice where a source of lubricant isn't part of the system (i.e. the operator must periodically oil the works).

.RC.
09-22-2011, 06:01 PM
I think a replacement ball bearing will not be suitable...

It is 6mm ID, 10mm OD, and while I am sure because it was chinese was a fair part of why it collapsed, I doubt even a good qualioty bearing of such a small size would last long with the sideways pressure put on it from the reduction gears...

Kansas_Farmer
09-22-2011, 09:33 PM
SAE660 bronze shaft is what I use for plain bronze bushings...they don't last long and are always in need of oil. Search for VXD Bearings on Ebay, they have all kinds of sealed ball bearings available on the cheap. I fixed the beater bar on the wife's carpet vac with a couple from em.