Using zinc rod for first time

Hello everyone,
I'm finally going to try some of that zinc filler rod for the first
time to repair a cast aluminum barbecue top that cracked. The ones I
bought don't have any instructions and I don't know if I should use
propane, MAPP, or OA. I definitely want to avoid melting/wrecking the
barbecue and, of course, have no idea what alloy the top is.
Can you folks give me some advice please?
Thank you as always,
--George
Reply to
George
Loading thread data ...
Propane would work for me, but I have big fat air torches... a weenie soldering torch probably won't do anything to a grill cover, unless it's thin. MAPP in the same size is ditto unless you have a bigger torch - then absolutely. O/A seems like too much bother to me, though it'll certainly get there fast!
Does this stuff come with flux or do you rub it in? You'll probably want to vee out the crack if not.
Tim
-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @
formatting link

Reply to
Tim Williams
It's just the rod without anything on it.
For propane, all I have is your basic soldering torch from Bernzomatic.
Hmmm.... I'll vee out the cracks. I can take the grill hood off so gravity can work with me. I'll just use my OA torch but be careful about trying not to melt my aluminum.
I'm going to do it either yet today or tomorrow. I'll let you know how I fare.
--George
Reply to
George
If you don't have the new "turbo torch" type hi-swirl BernzoMatic, forget propane = and even MAPP will be a stretch. With the turbotorch Mapp will work fine, and you MIGHT get by with propane. Clean the repair area thoroughly, and "V" out slightly. Heat untill the rod just melts on the aluminum surface, and rub/scratch it in. I use a piece of stainless steel wire to scratch through the melted repair rod to break up any oxide on the aluminum, and it worls pretty good.
Reply to
nospam.clare.nce
Check out
formatting link
Directions for using their 3-in-1 rod, which is one version of "that zinc filler rod".
Reply to
Don Foreman
It coesn't come with flux and is generally touted as needing none -- but a flux is available. Welco #52.
I've never thought much of that zinc filler rod for aluminum, though it works well on potmetal. There used to be a material I think was called "sealcore" for gas brazing aluminum. It has flux inside the rod. It runs a bit hotter than the zinc stuff but I had very good results with it as a beginner with O/A on aluminum.
I've since spent the time (and metal) to learn to weld aluminum with O/A, but that skill isn't learned in an afternoon or five. I was able to get strong joints with sealcore as a beginner with zero experience. Butt-brazed aluminum tubing to add extensions on an outdoor clothesline thingy. Much to my amazement, it worked. The clothespole outlasted the marriage...
Reply to
Don Foreman
I didn't get a chance yesterday, so I'm doing the repair today. I don't have anything fancy for propane, so I'll juse use the OA and watch the heat.
Reply to
George
I got a aluminum welding kit from TinmanTech, but I haven't use it a lot - at least not for 6 months anyways - plus I have no idea what the aluminum alloy is for the hood. It's just cracking around its hinges and I just want to strengthen it before it actually breaks.
Reply to
George
I'll keep an eye out for it the next go-around. Right now, I just want to fix it and get it off the honey-do list.
Reply to
George
Well, it's zinc'd together. The OA was a bit of a challenge - it heated up the base metal pretty quick even with a "0" tip on my Victor. The best method seemed to be to swirled the heat on the base and then dab with the zinc when the base was hot. Oh well. If I have it happen again, I'll just use my TinMan stuff. I guess I was hoping for super easy ... To me, it wasn't that much easier than mixing up the aluminum flux paste and then dabbing with the wire when the flux liquifies. Live and learn I guess.
--G--
P.S. I tried to wear down my wife all summer to let me get a TIG ... didn't happen :-)
Reply to
George
You have to bring the heat up slower than an oxy acet torch will allow you too. As the temp comes up "scritch" at the work area with the rod. It will not flow out like solder or brazing rod. Too much heat too fast and the zinc just burns off.
Overheat the already done areas, and the zinc burns off.
This stuff works OK, once you get the technique down.
Cheers Trevor Jones
Reply to
Trevor Jones

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.