where can i buy 42mm 18 ga copper tube

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werowance

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trying to find a place to buy some 42mm 18 gauge copper tube for a boiler. tried speedy metals and a few of the online places i have purchased from before. any suggestions? preferably a USA source or somwhere that will ship to the US reasonably.

anyone have a goto for their metals?
 
42mm is a fairly stock plumbing size in the UK and has a wall thickness of 1.2mm which is just about 18g. Problem is most places will sell by the 3m length.

ebay.co.uk has listings for cut lengths from 100mm upwards but postage may be a killer

What is the design you are following ? could you go to 1 5/8" OD which would probably be easier to get hold of in the US
 
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trying to find a place to buy some 42mm 18 gauge copper tube for a boiler. tried speedy metals and a few of the online places i have purchased from before. any suggestions? preferably a USA source or somwhere that will ship to the US reasonably.

anyone have a goto for their metals?
I think that is 1 ½ copper pipe it comes type K, L & M for wall thickness.
Trying to fined it metric could problem most Americans would use pipe sizes.

Just look up internet under pipe.

Dave
 
42mm is a fairly stock plumbing size in the UK and has a wall thickness of 1.2mm which is just about 18g. Problem is most places will sell by the 3m length.

ebay.co.uk has listings for cut lengths from 100mm upwards but postage may be a killer

What is the design you are following ? could you go to 1 5/8" OD which would probably be easier to get hold of in the US
i was looking at the Kenneth Wells traction engine. right now just pricing stock to see if its something i for sure want to pursue.
 
I think that is 1 ½ copper pipe it comes type K, L & M for wall thickness.
Trying to fined it metric could problem most Americans would use pipe sizes.

Just look up internet under pipe.

Dave
so if i look it up under pipe then wont it give me seamed pipe instead of seamless tube? just remembering that pipe vs tube was a no no for boilers because of the seam in them. is that so or how do you tell for sure when buying?
 
Wells was English and would have written that book at the time metric had been in use in schools so that would explain the 42mm OD and 1.2mm wall.

In teh US you could go with Nominal 1 1/2" type M copper tube. This has a 1 5/8" OD or 41. 275mm OD and a bore of 38.786mm which would give an wall thickness of 1.25mm which is a touch over the specified 18g and combined with teh slightly smaller OD would not be any weaker.

copper.JPG
 
Try an air-conditioning/refrigeration contractor. Explain what you're building and you might get an offcut for free. It usually doesn't pay for them to keep short lengths around so they go into the scrap bin. If all else fails, doughnuts are always a good bribe.
 
I have a bunch of 35mm O.D. x 1.2mm wall (standard 1-1/4 Type L) copper tube.

The 42mm you want is very close to 1-1/2" Type L or Type M. (41.3mm x 1.5mm or 1.2mm). A good possibility might be an old established plumbing business in a city where codes required lots of copper pipe. They still might be using 1-1/2" copper.

A final place might be a BIG recycling yard. Copper is binging very good money ($3+ per pound) these days and you never know what somebody might have just cashed in on.
 
so if i look it up under pipe then wont it give me seamed pipe instead of seamless tube? just remembering that pipe vs tube was a no no for boilers because of the seam in them. is that so or how do you tell for sure when buying?
Copper pipe is seamless.
I can tell why they call pipe but is used for steam. You can lookup pressure and the type you to be safe. There other types for higher pressure too and will cost more.

When see it in metric someone has covert from pipe size to metric.

Dave
 
Thanks for the info, i have been able to source it now in US or imperial size now. that was a big help folks. also i didnt know that copper pipe was seamless so that was good information. next steps are to 3d print the patterns for the smoke stack and wheels and try to cast them. been playing around with casting and getting better and better results. i have a 50lb bag of 120 mesh sand on the way to see if i can get a better finish with that vs the play sand ive been using. if i can pull that off then i have my winter project decided on.
 
There are some patterns on the web that can be downloaded if you have not already done the CAD. Not sure how good they are

https://cults3d.com/en/3d-model/game/kenneth-wells-traction-engine-casting-patterns
i actually have them. got them from thingy verse but they are the same ones. actually have one half of the smoke box printing in my resin printer right now. hope it comes out good. that resin printer i have is hit / miss. but when its a hit its a really good print
 
well, i think im going to be able to cast the pieces to make this traction engine. thanks to the help of everyone in this post as well as in another post i have concerning the finish of castings. these are by no means perfect but i can certainly use them and am happy about them considering how much of a newb i am.
the top wheel is a professional cast wheel that goes to another traction engine i started but decided to stop until i got better at the hobby. the bottom 2 are the ones i cast for this engine last week while on vacation. they arent as good as the professional one on top but i think usable

1721738407558.png
 
well, i think im going to be able to cast the pieces to make this traction engine. thanks to the help of everyone in this post as well as in another post i have concerning the finish of castings. these are by no means perfect but i can certainly use them and am happy about them considering how much of a newb i am.
the top wheel is a professional cast wheel that goes to another traction engine i started but decided to stop until i got better at the hobby. the bottom 2 are the ones i cast for this engine last week while on vacation. they arent as good as the professional one on top but i think usable

View attachment 158415
These look great bit of a file and clean up these will be very useable
 
well, i think im going to be able to cast the pieces to make this traction engine. thanks to the help of everyone in this post as well as in another post i have concerning the finish of castings. these are by no means perfect but i can certainly use them and am happy about them considering how much of a newb i am.
the top wheel is a professional cast wheel that goes to another traction engine i started but decided to stop until i got better at the hobby. the bottom 2 are the ones i cast for this engine last week while on vacation. they arent as good as the professional one on top but i think usable

View attachment 158415

Your flywheels look great.
Aluminum castings quality is all about using the right pour temperature (about 1,350 F, + -) and finding some good sand such as Petrobond (tm).

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