A technology exists whereas an apparatus looking alot like a paint spray gun is used to apply a molten or semi molten stream of metal to a part to buid up the part to repair from wear. From what I have read about it, this process is used by many industries to salvage worn out parts that would be extremely expensive to replace. I am wondering if thermal spray has been used or has been considered for use in railway preservation.

I could see several applications from build up of worn driver axles and pedestals to cylinder walls, piston rods etc. The material that could be applied can be basically any metal and can be machined to the desired finsihed size.

With the cost of replacing big ticket items like driver axles and the like, it may be cheaper and more practical to thermal spray the metal back onto the axle and machining to finished size.

Any thoughts? Is it applicable to steam locomotive repair and maintenance? What would the pros and cons be?


jrowlands@neo.rr.com

IRM just recently used a process called Metalizing, which sounds a lot like what you described, to "build up" and machine two worn axles from a lightweight interurban car. The axles were sent out to a contractor to do this, and as far as I know it turned out well.

Frank Hicks

fullparallel@wideopenwest.com

> IRM just recently used a process called
> Metalizing, which sounds a lot like what you
> described, to "build up" and
> machine two worn axles from a lightweight
> interurban car. The axles were sent out to a
> contractor to do this, and as far as I know
> it turned out well.

> Frank Hicks

That is exactly what I was talking about. I wonder what the cost difference that would have been between doing that and any other repair method, including replacing the axle. Also wonder how the repair is holding out.

jrowlands@neo.rr.com

hi. i think it is not a good thing to do. hartford steam boiler will not insure a sprayed shaft. they have been known to fail .ussually the spray pells off when this happens. a axel could be welded up and then turned. however itmustbe preheated and welded as a high corbon weld or it will fail. if you don't know how to weld high corbon or alloy material don't do it. regards bb

staybolt2@netscape.net

> That is exactly what I was talking about. I
> wonder what the cost difference that would
> have been between doing that and any other
> repair method, including replacing the axle.
> Also wonder how the repair is holding out.

I have heard that there is a spray-on process used to build up roller-bearing axle ends in railroad use. Question has been if this would work for solid bearings. Last I knew, our contact person had not yet asked the local shop that does railroad and commutter engine and car work (where he heard about it).

We have an ex-park engine that has almost new wheels under the tender. But the axle bearing ends have pitting, probably from the lawn sprinker water getting into the journal boxes.

Brain Norden

bnorden49@earthlink.net

> I have heard that there is a spray-on
> process used to build up roller-bearing axle
> ends in railroad use. Question has been if
> this would work for solid bearings. Last I
> knew, our contact person had not yet asked
> the local shop that does railroad and
> commutter engine and car work (where he
> heard about it).

> We have an ex-park engine that has almost
> new wheels under the tender. But the axle
> bearing ends have pitting, probably from the
> lawn sprinker water getting into the journal
> boxes.

> Brain Norden

Brian; It is possible to remachine the axle
bearing surfaces if they are within tolerances.
If you don't have the equipment others like the
Tennessee Valley RR Asn do and they can tell you how to measure your axles to see if they qualify for remachining. There may be others closer to you, check with them.
If it is necessary to replace the axles the new axles would be machined to fit the wheels you have and those same people can do the work for you. It's no big deal,IF you have the equipment.

Jim



rrfanjim@mvn.net