Winson exhaust

[fordfocus54]

Can anyone tell me what thread Winson's used on the cylinder exhaust pipe?

[trainman]

Hi,

The thread appears to be 26 tpi (whitworth), with an outside diameter across the threads of 0.495inch. I have determined this using a thread gauge, but there isn't an awful lot of thread to work with on the steam pipe and even less on the cylinder.

I was hoping to cross check my findings against the Spink drawing, but unfortunately this shows a flange joint onto the cylinder from the steam pipe.

Hope this helps.

Paul

[fordfocus54]

Hi Paul,
The exhaust on my Brit is much larger, either an imperial 3/4" 16tpi(it could be a unf thread) or a metric size (19mm). Unfortunately I don't have a thread gauge to check the pitch.
I have built a new blast pipe and blower ring and want to mount this onto the pipe, as it's screwed on I can adjust the choke distance between the blast pipe tip and the peticote.

[cplmickey]

I believe there are lots of similarities with the 9F so just been out to check mine. Unfortunately it's tucked in the corner of the shed so I couldn't reach the front end and I can't pull it out without help. If you haven't got an answer in the next few days then I'll see what I can do but it'll be next Friday at the earliest.

Winsons certainly used some odd threads in some places - the adapters I made to connect an airline to the threads in the smokebox were 5/8 x 26tpi which I think is Cycle thread. I think from memory I also came across metric in some areas.

Ian

[fordfocus54]

Hi all,
I had a word with Tracy tools this week and have sent the blastpipe locknut to them. Hopefully they can find out what thread it is and send me a tap.
If I do get an answer I'll report it here!

Frank.

[fordfocus54]

I got an answer from them today it's 19mm x 1.5mm pitch.

[trainman]

I think I have been barking up the wrong tree here. To try and clarify I will add some pictures (when I can remember how to do it). The thread size I described previously was the STEAM INLET connection to the cylinder. On the back of my cylinders there is a machined slot that is the exhaust port. There is a cylinder mounting plate bolted to the cylinder casting which is in turn bolted to the frames. On the inside of the frames there is then a bolted manifold which goes to the exhaust ring. Is this different to yours?

[trainman]

Hopefully the pictures will appear now!!

[cplmickey]

I read it as being that big thread in your last picture that the blast nozzle is screwed onto.

[fordfocus54]

Hello cplmickey
Lovely photos! Yes that big thread was the one I was enquiring about, the Brit cylinders are machined in exactly the same way as your 9F.
I must have a go at uploading some pictures as I've also modified the ashpan with 3 drop down doors and a removable side so that the grate can be removed without having to take the boiler off.

[trainman]

Hi,

I had to read the thread again on how to post pictures before I got it to work. I use Photobucket and it is very straight forward.

I have had a new ashpan cut out from 1.5 mm stainless steel plate, but I haven't got it bent yet. It would be great to your pictures of what you have done.

Paul

[fordfocus54]

Hi Paul,
At long last I have posted the ashpan photo please have a look at the Britannia ashpan thread.

Frank.