Re bushing boiler

[Mark TyldesleyParticipant @marktyldesley75376]

[Mark TyldesleyParticipant @marktyldesley75376]

Hi All,

i have a boiler, that needs some repair to clack bushes, the thread on one is is almost non existent, and the other is completely missing, is it possible to have theses repaired? Ie new bushes fitted n tapped.

Many thanks

Mark

[John BaguleyParticipant @johnbaguley78655]

Hi Mark,

It would be possible to drill out the old bushes and fit new ones or silver solder in a bush that can be rethreaded. The silver soldering might be best done with oxy acetylene to keep the heat local. Depends where the bushes are.

Can you not simply tap the bushes the next size up and make/buy new clacks to suit? Alternatively, drill and tap the bushes to as large a size as possible and fit threaded adapters to bring the thread back to original size?

John

Edited By John Baguley on 12/08/2014 09:28:37

[Nigel BennettParticipant @nigelbennett69913]

Mark

John's suggestion to re-tap the bushes is probably your best bet. Don't forget that there are 9/32" x 40 taps available, and you can probably source others 1/32" larger than you have now; I don't know what size yours are.

[stan pearson 1Participant @stanpearson1]

Mark

Unless you are very skilled with oxy acetylene and boiler making don't go down the new bush road, do as John said tap out and fit adapters to original size.

Stan

[Mark TyldesleyParticipant @marktyldesley75376]

Hi Guys,

Thanks for all your advice, i shall be taking the re tapping route, as suggested, so id better start looking for a good set of Taps! So what would you recommend in sizes, or most common sizes that i may encounter?

Thanks in advance

Mark

[Nigel BennettParticipant @nigelbennett69913]

It would help if we knew how big the boiler is! What's it off – a Gauge 1 Mamod or a 15" gauge 4-6-2?

Assuming a standard model-engineering-type 3.1/2" or 5" gauge loco (or 1.1/2" or 2" scale traction engine) , 1/4" x 40 or 5/16" x 32 are likely sizes.

1/4" x 40 should easily open up too 9/32" x 40, which is a relatively common size.

5/16" x 32 (if there's enough material in the bush) could be re-tapped 3/8" x 32.. An expensive option would be 11/32" x 32 tap and die, which would be the least invasive option for a 5/16" thread, but it may take some searching to find them. (Amazon in the US has them, but neither Avon nor Tracy have them off the shelf.

Hope that helps.

[JasonBModerator @jasonb]

M9x0.75 would be a good size up from the 5/16×32 and readily available, you would have to make both parts but thats likely to be teh case with 11/32×32 anyway. Tracy do that size

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