I'm no pro, but have done a fair amount of sweating copper joints. I always clean the heck out of the fittings, apply Oatey #95 tinning flux to the joint, and then use a propane torch to heat the fitting (not the tubing). I heat up the fitting, and after the flux boils away, touch the solder to the opposite side of my torch periodically to see if it'll melt and keep doing it until it melts. This has worked fine in the past.
Problem is, I've been trying to sweat fittings onto a shower valve and on about half of them (in this case I'm heating the valve part, not the thinner fittings), I couldn't get the solder to melt ... even after heating them for about 5-10 minutes with my propane torch, with about a 3 inch flame, touching the inner cone of the flame to the female part of the joint. In fact, the valve fitting was starting to become discolored and the flux melted, so it seemed like it was well heated.
This valve wasn't connected to the water supply yet, so there wasn't any water in the fittings or valve. Is there any other reason why solder won't melt? This is a no-name brand of solder, but it worked fine in the past and worked fine and melted on half of the joints. My torch is getting low on propane, but the flame seemed fine. As I heat the joint, I try to move the flame around, from left side to bottom to right, etc., but maybe I'm doing this too fast? Sometimes an inch length of solder would break off and fall when I touched it to the joint, if that's any clue as to what is going on.
So my main question is, because the solder didn't melt, is the only reason that it wasn't heated enough? The prep of the joint wouldn't have anything to do with whether the solder melts, would it? I'd think if it was prepped incorrectly, the solder would melt, but just not get sucked into the joint. Is it possible to have the joint too hot causing the solder not to melt? I saw that on another forum somewhere, where someone said if the joint is too hot, the solder won't melt, but that seems unlikely to me.
I'll probably buy a MAPP torch to replace this propane one, but shouldn't a propane torch be adequate for non-pros who don't mind if it takes a bit longer? I'll get some Oatey solder too to replace the generic stuff, but I'm still curious as to what I'm doing wrong when the solder won't melt?
Problem is, I've been trying to sweat fittings onto a shower valve and on about half of them (in this case I'm heating the valve part, not the thinner fittings), I couldn't get the solder to melt ... even after heating them for about 5-10 minutes with my propane torch, with about a 3 inch flame, touching the inner cone of the flame to the female part of the joint. In fact, the valve fitting was starting to become discolored and the flux melted, so it seemed like it was well heated.
This valve wasn't connected to the water supply yet, so there wasn't any water in the fittings or valve. Is there any other reason why solder won't melt? This is a no-name brand of solder, but it worked fine in the past and worked fine and melted on half of the joints. My torch is getting low on propane, but the flame seemed fine. As I heat the joint, I try to move the flame around, from left side to bottom to right, etc., but maybe I'm doing this too fast? Sometimes an inch length of solder would break off and fall when I touched it to the joint, if that's any clue as to what is going on.
So my main question is, because the solder didn't melt, is the only reason that it wasn't heated enough? The prep of the joint wouldn't have anything to do with whether the solder melts, would it? I'd think if it was prepped incorrectly, the solder would melt, but just not get sucked into the joint. Is it possible to have the joint too hot causing the solder not to melt? I saw that on another forum somewhere, where someone said if the joint is too hot, the solder won't melt, but that seems unlikely to me.
I'll probably buy a MAPP torch to replace this propane one, but shouldn't a propane torch be adequate for non-pros who don't mind if it takes a bit longer? I'll get some Oatey solder too to replace the generic stuff, but I'm still curious as to what I'm doing wrong when the solder won't melt?
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