Can’t stop droplet from forming on bottom of braze joint

[PortalKeeper]

I’ve been trying to get a crown to form so that my nails can slide smoothly over the joint without getting caught on anything, but I think I am using too much braze and still not getting the crown I want. Instead it all flows down to the bottom I think and forms these droplets. Any tips for this issue? I use sil-fos 15% by Lucas milhaupt.

https://ibb.co/1QTx3tB

https://ibb.co/sJ0ZsN7

[pecmsg]

Too much solder.
Practice
Practice
Practice

[R600a]

Yeah it's going to let the joint cool down a bit after you get the joint fully filled and then hit it with a little bit more on the spots that you need to fill in just melt the rod into it and feather it out with the torch.
I'm terrible at not leaving a drip underneath but I don't worry too much about it because I know it's not going to leak.

[Special-K]

Looks like too much heat. Learn to work the flame...get it hot enough to start the brazing rod flowing and then pull the heat back some so the filler will stay thicker.

[BBeerme]

Too much heat to not get that crown, if I understand your definition of crown.

Nothing wrong with a drop on the bottom. I get those all the time. It is almost necessary in difficult positions. I don't care how much solder drips off so long as I don't need to re-heat the joint.

You can put the crown on at tne very end with lower heat (pull your torch a bit away).

Those solder joints look beatiful to me. You wanna know why? Not enough heat and they would would be gloppy, not nice and smooth. Too much heat and you burn the flux (phosphorus) out of the Sil-phos, you'd have bubbles everywhere that would look like little exploding volcanoes.

Don't worry about the drop on the bottom so long as it is nice and smooth.

Well, now that I look back on that photo, not smooth enough, too much heat. Work on getting it nice and smooth, then you can address anything else you want.

[2sac]

If it doesn't leak...

[ehsx]

Poor heat control•

[BigDanB]

Better a drip than a leak.....

[rider77]

Too hot. Let the braze remain a semi solid. Just barely liquefied. It’ll flow nice but “stick” where you put it.

[kdean1]

There seems to be a lot of solder on the male pipe. The best method is to start by heating the male pipe so the heat will conduct into the fitting, Then move the flame onto the female portion so the rod will be drawn into the fitting.
As the saying goes “heat the pole, not the hole.”

[PortalKeeper]

Thanks for all the advice guys. I really appreciate it. Going to use these tips when I try again tomorrow.

[itsiceman]

Are you starting with the torch on top and finishing on the bottom?
Start on the bottom and work to the top.

[Poodle Head Mikey]

Too much heat on the joint.

PHM
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I’ve been trying to get a crown to form so that my nails can slide smoothly over the joint without getting caught on anything, but I think I am using too much braze and still not getting the crown I want. Instead it all flows down to the bottom I think and forms these droplets. Any tips for this issue? I use sil-fos 15% by Lucas milhaupt.

https://ibb.co/1QTx3tB

https://ibb.co/sJ0ZsN7

[Cal50]

Too much heat will also bubble the solder / braze in the joint and create voids and more prone to leaking.
If it seals it works but the blob is just wasting filler metal.

Lower heat / less filler for a better joint.

[pecmsg]

https://www.harrisproductsgroup.com/...-Center/Videos

[gustavhorna]

the trick is to heat high the joint and make the solder penetrate the inside, then reduce the heat to form the final crown... just a 2 stage process

[hvacker]

Simple concept but hard to teach. "solder follows the heat". Capillary attraction. Good heat control will "suck" the solder into the fitting. Don't be concerned about the radius until the joint is almost done.

There's a Goldilocks point concerning heat. Not too hot, not too cold, but just right. Use a fairly soft flame.
Something I used that raised some eyebrows is my cutting head. While I worked a lot of somewhat larger fittings than some, I found
a cutting head is like a rosebud. It made quick work of most braze joints w/o giving me grief. I have said "Try it, you might find it a god
addition to a tool box. Not every job but some will be a good fit. Why not use a rosebud? Didn't need one, I had a cut head.")

Speaking of rosebuds, They are a good addition for some work also. Especially where space is a problem and a lot of heat is needed
as fast as practical w/o loosing control.
For small stuff, up to 7/8 or even 1" I find for a lot of work a TurboTorch or an air acetylene can work better than an oxy/acc torch.
They run somewhat cooler and have better heat control than the often over capacity of an oxy/acc torch. They tend to envelope the fitting better. Less tendency to boil the solder that's a major cause of leaks.
They do take more work space as the flame is larger. I prefer them on small stuff as long as I have space and don't need a lot of heat fast.

[R600a]

I agree with @hvacker a rosebud or cutting tip is amazing when you need it! I just got a rosebud and I wish I bought it a few years ago.

[ehsx]

I agree with @hvacker a rosebud or cutting tip is amazing when you need it! I just got a rosebud and I wish I bought it a few years ago.

Rarely need a rosebud under 2" pipe. Been training an international component mfg on distributor plate brazing. Harris 0, #8 mono tip.

[TechmanTerry]

I would be worried if the drip was on the top of the joint