Couple of decorating Qs: old rad pipes, and filling plasterboard

[disco_monkey79]

Hi all,

Calling on help from the UKW brain trust...

I have moved several radiators, which has left large-ish holes in the ceiling where the old pipes used to run. Any tips on product for filling these? Holes are approx. 3" by 1.5", so a bit too big to just splurge caulk.

Also, the next rad to be changed will be staying in the same location as the old one, so will need joining to the existing (and heavily painted) pipework. It's a slightly different width, so will need to adjust the valve locations slightly.

My question is: with sufficient elbow grease, am I likely to get the old pipes clean enough for a soldered joint? Or shall I just go for a compression fixing? I have already had issues soldering to old (an unpainted) pipes, in spite of thorough cleaning. Whereas soldering brand new pipe has been a doddle.

Much obliged

 

[Spectric]

My question is: with sufficient elbow grease, am I likely to get the old pipes clean enough for a soldered joint? Or shall I just go for a compression fixing? I have already had issues soldering to old (an unpainted) pipes, in spite of thorough cleaning. Whereas soldering brand new pipe has been a doddle.

You must get the pipe clean, using wire wool and plenty of flux and don't attempt to solder until it is spotless. It is just something you have to deal with in plumbing and also make sure the old pipe is 15mm and not 1/2 inch.

As for your holes, I would slip a piece of wood through the hole and screw to ceiling, then a bit of plasterboard can be fixed to that and finish with plaster filler.

 

[disco_monkey79]

Thanks for your reply. I cleaned the old pipes until they shone, using abrasive strips specifically for the purpose, so not sure how much cleaner I could have got them. Interesting point re 1/2" - perhaps that was the issue.

 

[eribaMotters]

As above regarding holes in plaster. I also use Gyproc Easifill for larger areas or deeper holes instead of a filler. It goes off quickly, does not shrink and sands easily. Different setting speeds are available.

Colin

 

[Spectric]

You can get 1/2 to 15mm couplers but as the years pass there is less and less 1/2 still out there.

 

[owen]

If you don't want to solder the old pipe, I would clean it up anf use hep2o push fit joints, far less likely to leak than compression fittings. Also, if you're soldering you'll want to get all the water out of the pipes which with the hep2o you don't need to bother.
As for fixing the holes, if you can't be bothered with the small bit of plasterboard and a piece of timber then a couple of squirts of expanding foam would sort it, then just cut it off flat and fill over it.

 

[Dazed]

I think you've already had good advice on the plaster work. I like Gyproc Easifill too, it's good stuff. Even finish plaster is better than Polyfilla etc.

Never a problem cleaning up old pipework for soldering unless it's badly pitted or corroded. Not usually the case if removing paint. Avoid papers like emery, there's sometimes a carbon lubricant that can inhibit solder wetting. Wet'n'dry to remove paint, finish with clean wire wool and a wipe with clean rag/paper. Use a modern flux like Fry's Powerflow and for non potable pipework I prefer leaded solder, it wets more easily. Modern fluxes are so much better that the latter point is less important.
You can buy metric/imperial pipe couplers but 1/2in and 15mm pipe are so close that you can often manage without, depending on the fitting. Prefer end feed fittings, and slip couplings are great when joining already fixed inline pipe.

Sorry if this is already familiar to you.
Steve

 

[disco_monkey79]

Thanks all for the advice.

 

[flying haggis]

if you dont want to solder and dont want to see a white pushfit joiner pegler do copper pushfit
https://www.toolstation.com/pegler-yorkshire-tectite-sprint-push-fit-straight-coupler/p40051
bl**dy good they are too (but be careful pushing them on as the centre stop on the straight ones is not very good as a stop !)

 

[scooby]

As for your holes, I would slip a piece of wood through the hole and screw to ceiling, then a bit of plasterboard can be fixed to that and finish with plaster filler.

Thats what I do. As additional, I put a screw in the middle of the timber piece and leave it stuck out a bit. Allows you to get the claw of a hammer on it so you pull the piece against the plasterboard whilst you get some screws in it.

 

[Just4Fun]

If you can solder new pipes but not existing pipes one possibility is that there is water in the existing pipes. Not necessarily visible at the fitting but not too far away. The water will prevent the pipe heating up enough for the solder to melt.

 

[Phil Pascoe]

Get a short bit of batten and put some thin adhesive like No More Nails on it. Push it up through the hole with a bit of string around and pull it down to squeeze out the adhesive and leave it for twenty four hours. You can then stick a patch in and fill around it. You should be able to solder from 1/2" to 15mm - 1/2" was the internal measurement and 15mm is an external one. (It doesn't work for 22m and 3/4" though.)

 

[glenfield2]

For joints that can’t easily be soldered Texture Classic is a very tidy looking range of push-fit brass fittings for copper pipe that can be taken apart with a little plastic tool. (So far) I’ve had 100% success rate with them which is a lot higher than I get with compression.

 

[TomGW]

I have had to fill a significant number of large holes in the ceiling where older, large dia spotlights were removed when they were being replaced with new led versions in different locations. I used a tank/hole cutter to make the existing ragged holes larger and round, using a pre-cut plywood scrap to centre the cutter. Then cut circles of plasterboard using the next largest cutter, which fitted perfectly. Stuck in with Gripfill and skimmed over.
You need to be careful of a lot of fillers which are more ‘plastic’ than bog standard, powdered Pollyfilla. They will show up under the paint as they are a different material and it will seem that you didn’t get the surface flat.

 

[Phil Pascoe]

^^^^ Dry lining filler works.

 

[Bm101]

Another variant on the hole filling is use a hole saw to cut out a circle in the damaged area. Cut another blank the same size and tie a pencil etc above it in the existing plaster. Thread the new blank and pull it tight and tie off. Dab some bonding/skim etc to fill the gaps, cut the string when dry then skim or finish.
#Source: Actual Plasterer. This is a 3 minute solution.

 

[Phil Pascoe]

However you cut the plaster board ceiling or patch, run a Stanley knife around the circumference to take off the torn paper and leave a clean edge. It'll be much easier to sand cleanly.

 

[Just4Fun]

Another variant on the hole filling is use a hole saw to cut out a circle in the damaged area. Cut another blank the same size and tie a pencil etc above it in the existing plaster. Thread the new blank and pull it tight and tie off. Dab some bonding/skim etc to fill the gaps, cut the string when dry then skim or finish.
#Source: Actual Plasterer. This is a 3 minute solution.

Meanwhile there is aa chippie on the same site wondering why he keeps losing pencils