By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Allendale Jan 24th

Copper pipe selection

for steam fittings

All Topics | Latest Posts

Search for:  in Thread Title in  
GaryM08/05/2014 15:12:35
avatar
314 forum posts
44 photos

Hi,

Simple question that I cannot find the answer to anywhere.

A while ago I bought some copper pipe for connecting to the S50 that I'm making (on hold at the moment).

The pipe I bought is 5/32" OD 0.014" wall thickness (28 SWG ?) from Reeves as here

**LINK**

Later I thought I might use 1/8" pipe instead so at last years Midlands show I bought some 1/8" OD from Blackgates. However this pipe has a much thicker wall (~1/32" and is coiled whereas the Reeves pipe is dead straight.

Which is the correct sort to use and does it matter?

Note this is for connecting pipe not a potential boiler.

Thanks for any replies.

Gary

Anthony08/05/2014 16:26:40
6 forum posts
3 photos

I built the S50 last winter, and used car brake pipe for the inlet and exhaust, easily obtained and threads really good.

GaryM08/05/2014 16:43:49
avatar
314 forum posts
44 photos

Hi Anthony,

Thanks for the reply, but I don't want to thread it. I want to silver solder a union to it.

Gary

GaryM08/05/2014 16:48:32
avatar
314 forum posts
44 photos

Your S50 looks very nice by the way. I particularly like the main bearing caps and the cylinder cleading and banding.

Gary

Neil Wyatt08/05/2014 19:41:10
avatar
Moderator
18404 forum posts
718 photos
78 articles

The cunifer pipe ought to silver solder easily (at least I hope so - I have several feet retained as future steam pipe!)

Neil

AndyP08/05/2014 20:37:36
189 forum posts
30 photos

Gary

Using the formula and data here I calculated a safe working pressure of 738 psi for the thin wall 5/32 tube and no doubt the 1/8 would be higher so your choice.

Incidentally if you want dead straight copper pipe in the smaller sizes like this then at the expense of the end couple of inches just clamp one end in the vice and grip t'other end with favourite grips and pull - at some point you will feel a 'give' and there you go - straight tube.

Andy

Neil Wyatt08/05/2014 21:14:29
avatar
Moderator
18404 forum posts
718 photos
78 articles

Alternatively, for about 12" or so of tube, put it on a clean flat surface (e.g. a bit of worktop) and place something heavy, clean and flat on top. Rioll back and forth and the pipe will become very straight very quickly.

Neil

julian atkins08/05/2014 22:27:22
avatar
1235 forum posts
353 photos

if you pop into your local model shop you can get KS copper pipe 1/8"dia in thin wall section.

incidentally 3/16" dia thinwall stuff seems to be unobtainable these days unless someone knows of a source? ive very little of this size left.

cheers,

julian

John Baguley09/05/2014 02:40:29
avatar
475 forum posts
50 photos

Julian, the last lot of thin wall tubing I purchased was from Doug Hewson a couple of years back and he had 3/16".

Maidstone Engineering list 3/16" x 26swg as well.

I tend to use thin wall all the time as you can go down a size and still have the same bore as the thicker stuff.

John

GaryM09/05/2014 10:08:10
avatar
314 forum posts
44 photos

Thanks for the replies.

AndyP: I think I should be OK with 20psi then wink I might try your idea for straightening at some point, just out of curiosity.

Julian: Yes, I think the 5/32" was KS pipe, so I know you can get it.

John: "I tend to use thin wall all the time as you can go down a size and still have the same bore as the thicker stuff" Hadn't thought of that.

I just thought one sort might be easier to bend than the other and there seemed to be no guidance on any suppliers web sites. For that matter the whole subject of piping, unions, valves etc. never seems to get a mention in books or on web sites. Loads of build logs on engines and boilers but nothing on connecting them. Article Neil?

Off to Harrogate now. smiley

Gary

Neil Wyatt09/05/2014 10:30:43
avatar
Moderator
18404 forum posts
718 photos
78 articles

I have a very old ME article on 'standard unions' for steam pipes. I used it to make unions for my 10V, but on later models I used flanged joints as closer to scale.

If I can find it again, I'll put it up on this website.

If anyone wants to write up this subject afresh, it's probably an ME article rather than MEW.

Neil

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Latest Forum Posts
Support Our Partners
EngineDIY
Eccentric July 5 2018
cowells
Warco
ChesterUK
emcomachinetools
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest