rear tailwheel spring bracket Q

[Steve Pierce]

We have great primers and paints now days and our airplanes usually live in hangars. If you must just lay a bead of urethane caulk in there after covered.

[violinmaker]

I don't think I have ever brazed on any Cro-Mo--- and I think I don't want to anyway in general. Maybe the crack could have been from strain in the material possibly from the different expansion rated of brass-steel.

I am just visualizing that that tab is being yanked on 24/7 when flying--- and can imagine that ANY imperfection on its
surface, corners or edges is all most guaranteed to crack-- noticing that the area formed between the longeron and the
tab is a very tight triangular geometry--- I think it would be very difficult (for me anyway) to avoid some undercutting
at the edge of the weld bead...… which I would THINK would guarantee a problem later (a crack and separation--)

Even if the weld was perfect--- just the leftover discontinuity in the material from heating across it that much (haz)
seems risky considering what it is doing.

WOW Steve---- THAT is good to know---- because the bracket I cut off that may have been done by piper -WAS welded
across there--- and I didn't like the looks of it either.....

I am kind of afraid to apply anything else there because I know many of the things like caulks and bondo's and whathaveyou
do absorb some moisture over time- which could cause rust there under the primer/paint. Maybe I will just build up
several layers of epoxy primer there with a small brush after it is sprayed. I think I trust the primer (then paint) more than any other materials. Maybe some of that black 2-part windshield sealing compound MIGHT be OK since I never saw any
corrosion under it when digging it out an inch deep from King Air's . (cant remember the name of the stuff- came in the
mixing syringe)

I think just primer + paint ( both 2 part type Stewarts ) would be a safe choice (Yes ?)

(yes - once you braze- or solder on something--- no more welding there--- )

Thank you again Steve for that important tidbit---

Tim B.

[Steve Pierce]

Piper only welded there on some late model Super Cubs (must have been a new welder) and an AD was issued. Don't over think it. Piper built over well 20K rag and tube airplanes and knew what they were doing.

[violinmaker]

FYI--- I tend to overthink most things ! Im a recovering overthinker ----

According to what logs I have this thing has been through several prangs in the rear tubes. It was converted from 22 to 20
maybe in the late 1970's. The bracket may well have been replaced then--- as the longerons had been spliced.
Im down now to just getting my gaps as small as I can to make the welding easier. Seems like the tighter the fit the happier the bead goes on. !

The old welds on there older planes are just a work of art. I would never live long enough to make as pretty a gas weld as on these.... I guess that happens when it's 8 hours a day 5 days a week...…

Tim