Welding Pot Metal to Steel? Loose '49 Trunk Lid Handle

[Dan O]

My trunk lid handle is spinning freely on my 1949 Buick Roadmaster 76s.    I took it off the trunk and there is a steel shaft that sticks out of what I assume to be pot metal handle, thru the deck lid, and turns the latch mechanism.  The shaft has come loose from over use and just spins when I turn the handle.  I am afraid to braze it with a torch as it might just melt what I assume is pot metal on the handle.  I tried Gorilla 2 part epoxy but it did not stick (I think I cleaned it with paint thinner which might be the problem).

 

Anybody else fixed this problem before?  Glue seems easiest but perhaps impermanent.  TIG welding?

Edited May 8, 2021 by Dan O (see edit history)

[EmTee]

Maybe try installing a helicoil in the handle and rounding, then threading the shaft?  Use Locktite on the assembled handle & shaft to prevent it from loosening.  Or, try the epoxy again, but just as a filler.  Drill and install a roll pin through the handle & shaft to secure it.  This approach would be visible, but only upon close inspection...

[SBRMD]

Dan, I've got an extra handle if needed.  The cleaner one in the pics is my keeper, rustier one available.   Can't tell you about it's function, no key.

[JohnD1956]

That picture of the handles above seems to show a hole on the bottom of the shaft.  Is that for a set screw that may have come loose or fell out altogether?  If not can that hole be used for installing one now?

 

[buick man]

Just for thought considerations, pot metal vaporizes around 750 degrees range or so depending on the various metals used to make it in the first place as it is primarily Zinc based with various other metals thrown in for good measure all with various melting points.  Any and all types of welding will be much hotter then that and will vaporize the pot metal.  Then there is Muggy at 350 degrees melting point and is kinda like J-B Weld.  I would take the rusty one, clean it up and try to make it work.

[SBRMD]

David, you are so right about the welding/temps, etc. I have a grille half for my '49 that was cracked but no material missing.  Tried to weld it and vaporized some material, had to replace.

 

Edited November 4, 2022 by SBRMD (see edit history)

[drhach]

Also consider that zinc vapors are poisonous. Unless you have (very) good ventilation, you don't want to melt that base metal.

 

Brazing or silver solder may be a choice. A high silver content solder and MAPP gas might get you a good join. 

[Dan O]

On 5/9/2021 at 7:38 AM, SBRMD said:

Dan, I've got an extra handle if needed.  The cleaner one in the pics is my keeper, rustier one available.   Can't tell you about it's function, no key.

I have a couple of handles - the shafts vary in length for the different models.  The sedanette shaft is shorter  than the sedan and convertible apparently.  I will try and work with what I have but thanks for the offer.

[Dan O]

6 hours ago, drhach said:

Brazing or silver solder may be a choice. A high silver content solder and MAPP gas might get you a good join. 

I I know my propane torch will melt the pot metal of the trunk lid trim - perhaps not the handle but I'd hate to learn it will.  I tried brazing but could not get the solder to stick.  Am I doing it wrong?   I should watch a you tube video I guess.

 

I don't think the shaft comes out of the handle easily so a set screw is out (or too difficult). 

[Dan O]

On 5/9/2021 at 9:43 AM, JohnD1956 said:

That picture of the handles above seems to show a hole on the bottom of the shaft.  Is that for a set screw that may have come loose or fell out altogether?  If not can that hole be used for installing one now?

 

The hole you see at the end is for attaching the shaft to the trunk latch mechanism.  The square holes are for the locking mechanism that's turned with the key.

[buick man]

13 hours ago, SBRMD said:

David, you are so right about the welding/temps, etc.  I have a grille half for my '49 that was cracked but no material missing.  My body guys said "we can maybe fix that" and proceeded to essentially destroy it in their attempts to weld it up, necessitating a time-consuming and costly search for a replacement.

Yeah I hear Ya ... and I say Neanderthals but then again they would be leading man material in movies today what with their square chins and low foreheads.  

 

EDIT:  Actually anything you attempt short of making your own smelt mold and have have a arts n crafts furnace which you could realistically accomplish if you are artistic, melt some crap metal and pour into your mold.  Now that is a video I would like to see.  There are such on youtube and demonstrate how to make a mold then how to melt metals and create a new object.  Anything else such as attempting to Heat, Epoxy short of Midnight Witch Craft will only end in failure and attempting to glue or meld something together will only shear and break again.  

Edited May 11, 2021 by buick man (see edit history)

[JohnD1956]

Can it be braised, or soldered?  How was it originally attached?

[Dan O]

I finally took the part to my local specialty welding shop in Houston.  The welder there said he did not know a way to weld the non/semi-magnetic pot metal to the steel shaft.  BUT he did have a solution.  He simply tacked four beads onto the steel shaft in such a way as to block the shaft from turning against the handle: . 

 

 

Mission accomplished!