Part built Allchin 1.5 inch

Poppy trying to grab my head while uploading pictures.

Poppy made a lovely job of those machined parts Derek! Well done.

Never been able to teach any of our shop pets to sweep up, let alone turning and milling.

Thanks Jeff

Hi guys

Quick question, I'm about to buy some bolts or studding for the cylinder block.

does it need to be stainless steel bolts and studding or is just steel OK, stainless seems a lot harder to find.

Thank you in advance

As they go through into the boiler you want bronze or stainless

Thank Jason, how about the ones holding steam chest/exhaust pipe on etc?

Thank you

They can be steel.

Thanks Jas, I had a look at your fowler album today at work.

Lovely work, if I can end up being half as good as that in the years to come I would be very happy.

Derek,

Strictly speaking theory says avoid stainless steel for boiler studs as stainless unless a particular grade is vulnerable to crevice corrosion which will be exacabated by chlorine in tap water if that's what you run on. Certainly a full size boiler inspector would 'have a baby' seeing stainless studs in a full size boiler. Normal recommendation for those is EN3B.

However in practice for your boiler being copper and considering the size, stainless would probably be accepted by club inspectors and I doubt failure through crevice corrosion is very likely. Best choice though for your application I would say is bronze.

Paul.

IIRC, the Hughes' construction notes recommends 1/8" dia. PB threaded 5BA. Brass nuts are silver soldered onto the threaded rod to form dummy studs which can then be treated as hex. head bolts whilst having the correct appearance.

I suppose M3 could be substituted for 5BA.

clive

Hi All

Yes you are correct about Hughes book, I have to say I don't really like the thought of permanent studs incase one snapped or the thread stripped during assembly.

I think home made studs with stainless would work, I think the 2 inch burrell engine kit you can buy from steam traction world uses stainless bolts/studs into copper boiler.

Regards,

Derek

If you do go for stainless then you can use hex stock to make bolts but do them with a dome on the top of the head to look like a protruding stud.

good idea, thanks Jason

Thanks Clive and Paul for your comments

Wot, no two exposed threads of the stud for safety? For reference I will be using home made EN3B studs and EN1A nuts for holding the cylinder block on my traction engines; although they are larger scale and have steel boilers.

Andrew

No need for a specific amount of thread showing when it's all solid metal.

I think even the most avid rivit counter would have a job telling the one piece ones going into the boiler from the rest which are all nuts and studs especially under a coat of black paint.

I love how a simple question turns into a discussion, its great to see.

so they are your homemade studs on your fowler I see how you made them now.

they look good, I think I shall have a try and see how much stainless hex is however I do struggle with stainless on my lathe for some reason.

Hi Jason

Can you use stainless steel threaded rod and Loctite on stainless nuts and then round them off like yours or is this a failure to an inspector,

Regards,

Derek

Ideally silver solder the nuts to the studs to be sure that the stud comes out if you need to take things apart in the future. If you round over the end, screw the two together with some flux and then apply a tiny amount of solder to the top when the flux melts that should stop you clogging the thread with solder.

Bronze studding or rod you thread yourself and brass nuts will be easy to solder, if one or the other is stainless then use tenacity No5 or HT5 flux

Loctite would be acceptable too probably go for 648 which will take the heat better.