plating bearing surfaces?

[RichMiller]

Has anyone plated bearing surfaces on model engines?
I understand that the Allison V1710 engine had plated journals on the crankshafts and was wondering if it would be feasible to plate connecting rods, etc., with one of those silver plating kits that are available to repair jewelry and silverware. since split bearings are difficult to make and impossible to find for a model

 

[Tony Wells]

I'm only speculating, but I'd think those kits are intended for very thin deposits, and it might be difficult to achieve enough build-up to allow for finish machining or lapping. I'm doubt it would coat evenly enough to use as deposited, especially if you had to take extraordinary actions to build up a considerable thickness.

I don't know the cost of these kits, nor how much actual silver you get with them, but again speculating, it would seem to me that it would be a costly approach.

I've seen shim stock cut to fit around a split bearing on the outside, thus giving more collapse to tighten things up.

 

[pdentrem]

Uneven depositing of the metal, voids in the plate if attempting to build up the surface, metal grain size issues that can cause roughness of the surface. There are many work arounds for any of these problems.

Not to discourage you, it is not a straight forward process.

Plating is an art form. We send out a lot of stuff to plate and rework can be an issue. You may require several attempts to get what you are looking for. There is a large number of plating forums out there, I would suggest looking there if we do not have a resident plater here to answer your question.

 

[Inflight]

I once tried plating with copper sulfide. It gave a very thin coating which could be polished with fine abrasives. It worked well as a bearing surface against soft lead bearings.

I got the copper sulfide as a powder.

 

[RichMiller]

thanks for the answers, i think that the plating would be done over the lapping, though. I would only expect enough to make the parts slippery, but not too thick. I imagine that it would be less than .001". I have heard of the silver foil trick but have never seen it on an engine

 

[jgedde]

What about moly disulphide? I have some as a powder and some as a spray, both without added oil. The stuff really burnishes into the metal...

John

 

[Hawkeye]

John, moly will do interesting things to metal surfaces, but I doubt that it will build them up measurably. We had some pretty smooth handrails in the Black Hole when I worked in a copper/moly mine. Could be lots of fun if you stepped on a damp floor near the moly filters. Your foot would slide effortlessly until your shin hit something immovable. I still have a can of it in the shop.