Rescuing a Stuart Triple Expansion engine

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wgreeley

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I have obtained a Stuart Triple Expansion engine by an unknown builder. The problem I am having is locating replacement hardware The engine was built with 4-36 hex head machine screws. Does anyone know of a source for these.

Thanks
Bill
 
To get hex head, you will likely have to machine blanks from hex bar stock and buy a 4-36 die( ebay).

WOB
 
Are you sure that the screws are UNS 4-36 ? as you will have found out this is by no means a common thread.
It would be a crime to fit anything but scale hexagon head screws to your engine and a possible solution might be to re-tap the holes M4.
This will be a few thou larger on the screw diameter but screws are available with a size smaller head so that scale appearance can be maintained.
The same can be said for BA threads which I use for all my hexagon head screw modelling requirements , still easily obtainable here in the UK , but I have the stock of several long departed model engineers which will last me for my lifetime and leave plenty to pass on after.

Dan.
 
4x36 taps are available from Brownells', for use in gunsmithing. Across the pond, but available.
 
Yes the taps are available in the UK too , but how does that help ? Bill is looking for a source of suitable hexagon head screws .
Dan
 
I might be able to help, as I have that size thread tooling and a (limited) supply of 11/64" (.176" a/f) steel hex stock to produce a small batch of 4-36 screws. If .176" across the flats will work for you, let me know the length and quantity required.
Drillrod (nyc)
 
Forget Fastenal. On my last visit I saw a sigh that they were only selling business to business.
 
Thanks All
It looks like the screws were machined from 3/16 (.1875) hex stock. The same as an H.E. Boucher engine I am also working on. Looks lie the die approach is the best choice.
 
Hi. May not be relevant. I recently helped a friend get a Stuart engine sorted and that had been put together using 3, 5 & 7 BA bolts which had quite low profile hexagonal heads. This was a bit of a nuisance as being primarily an aeromodeller I use even numbered BA nuts, bolts etc.. Just not cricket using odd numbers!!!
 
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