Soldering 28mm

bsr · 5 Apr 2021

Good Evening

I have to solder a couple of fittings onto 28mm copper, vertical pipe. Will my propane torch be OK and are there are special tips for the larger pipe?

Thanks

bsr

oldbuffer · 5 Apr 2021

1.Propane should be enough for 28 mm pipes, provided you are reasonably proficient at soldering.
2. If you find it tricky, you could try using MAPP gas, which gives a hotter flame. However, if using, be careful not to burn the flus out of the joints.
3. No idea what torch you are using, but if something like a Rothenberger Surefire 2, the standard burner nozzle will be sufficient.

bsr · 6 Apr 2021

Thanks. I've got an old one of these (albeit without the fancy case):
https://www.machinemart.co.uk/p/fs555-gas-torch-kit/

I've heard of MAPP but never bought it as I've read it's too powerful for DIYers and likely to overheat the joint. I'd rather not spend a load of money on a new torch and gas when I'll probably never have to solder 28mm again! If necessary I've got two torches so I could always heat the joint using both.

As you can see the kit has a "pipe burner" attachment. I've never used it - has anyone else and are they a good idea?

oldbuffer · 6 Apr 2021

1. That's designed for a standard "barbecue" type propane gas bottle. The regulator won't fit a MAPP cylinder, and the burner may not be suitable anyway.
2. You're stuck with using propane, but I'd have thought that torch was up to the job.
3. I've never used that type of "pipe burner" attachment.
4. As heat rises I'd pre-heat the lower joint and tee branch (if any) first, pre-heat the top branch, bring the bottom (and tee) up to temperature and solder then finish off with the top branch. Normally I'd do it the other way round to stop the upper joint running into the lower, but with limited heat input you may want to maximise what you have.

Harry Bloomfield · 6 Apr 2021

bsr said:
As you can see the kit has a "pipe burner" attachment. I've never used it - has anyone else and are they a good idea?

They concentrate the heat around the pipe, but will it be a wide enough mouth for 28mm?

Maybe practise on a scrap bit of pipe first?

oldbutnotdead · 6 Apr 2021

That torch will be plenty for 28mm (had to do a load on the wet side of the woodburner). Same as 22 and 15- bring the area up to temp slowly so the joint starts flowing all the way round rather than 1 side hotspotting.

bsr · 12 Apr 2021

Thanks for your help, it was absolutely fine. Only took 15 seconds to heat the joint. The only thing I did differently was to touch the solder to the joint in several places as I didn't instantly get the silver line all the way round like I do with 15mm.

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Soldering 28mm

Similar threads