Filling holes

4x4M38 · Post by **4x4M38** » Sat Jul 25, 2015 3:00 pm

Pretty surprised the windshield frame has only a little pitting and rust through, mainly on the top of the rope channel. However, our friend Bubba over the years has been at work with this one.

There are holes in the top of the frame that I assume are for a civvy CJ top, which make sense. There are also a row, not a straight line, and definitely not spaced regularly, through the front face of the windshield. Some of the holes actually penetrate both the main sheet metal as well as the vertical portion of the rope channel. Some real high tech work there. I am thinking maybe the M38 top wore away at the corner of the rope channel and our friend just whacked the offending portion off and installed snaps in the edge and drilled umpteen holes to tie it down.

The holes are all about 1/4" in diameter. What is the best way to fill them? My brother in law suggested lead. However.........

Do I cut out a jillion 1/4" discs and mig them? Ideas?

Tks,
Brian

OKCM38CDN · Post by **OKCM38CDN** » Sat Jul 25, 2015 8:38 pm

I am working on a M-38A1 tub that is full of holes drilled for some civilian accessories... If they are just the sheet metal thickness I take a piece of copper bar and clamp it in place under the hole and fill it in with the MIG...

I would do the same for the ones that are multiple depth on your windshield... just being careful not to go to deep... no bar of course...

After the holes are filled I use an 80 grit or so sanding disk (the type with multiple pieces of paper around the disc) and sand the area smooth... I use a 4 1/2 inch grinder...

You just have to be patient and take your time to get it to look good... after a coat of good primer and paint never know the hole was there...

Hope this helps...

4x4M38 · Post by **4x4M38** » Sat Jul 25, 2015 9:47 pm

Hal,
Thanks for the reply. Moved here after 13 years in. B'Ville and
Ponca City. Will miss spring and fall and the duck hunting.

I have read about the copper backer. Does it not bond to the sheet
while welding? If so, do you just grind off?

Thanks,
Brian

southpw · Post by **southpw** » Sun Jul 26, 2015 5:15 am

I work in a fab shop and we use copper behind things we want to fill with weld. The metal and copper won'tbond together. But don't use a thin piece or the heat of the weld will melt the copper a little and then it will stick.
My windshield is in similar condition and plan on trying this to mine when I get to that part of the project. Currently it's a rolling chassis

4x4M38 · Post by **4x4M38** » Sun Jul 26, 2015 6:16 am

Thanks Brad!

Xamon · Post by **Xamon** » Sun Jul 26, 2015 7:21 am

I have read about this copper bit as well, how large should the copper piece be? also does it work if you are stick welding? Sorry for the interrupt I have a few holes to fill as well.

Post by **wesk** » Sun Jul 26, 2015 7:30 am

Here's a ton of info on using copper welding back-up or chill bars.

https://www.google.com/?gws_rd=ssl#q=co ... en+welding

Lincoln's web site covers arc-blow and using a copper chill bar.

http://www.lincolnelectric.com/en-us/su ... etail.aspx

Xamon · Post by **Xamon** » Mon Jul 27, 2015 7:14 am

Thanks Wes, I did not know what they were properly called so had difficulty finding information.

4x4M38 · Post by **4x4M38** » Mon Jul 27, 2015 12:35 pm

Ok,
Practicing my butt weld joins with 16 gauge until I can get some 18.

Making some progress, but when it hits 100 in the shade I head for cooler pastures.

I understand the backer bar concept. What do I do when I have blind holes, in other words, through holes in the sheet, but with no way to get a backer behind the metal where the holes are? For instance, in the front sides of the windshield.

Tks,
Brian

Post by **wesk** » Mon Jul 27, 2015 1:19 pm

Just google Welding 101 blind hole filling.

https://www.google.com/?gws_rd=ssl#q=we ... le+filling

I just plugged 10 holes in a steel door frame for an antique aircraft using good old fashioned Oxy/acetylene and it took all of 15 minutes. All blind holes and no way to back-up. The right temp, right flame, right motion and filler rod!

4x4M38 · Post by **4x4M38** » Mon Jul 27, 2015 8:46 pm

Are we talking brazing Wes?

Post by **wesk** » Mon Jul 27, 2015 9:02 pm

Had I been discussing brazing I would have gave you the link to "Brazing 101, blind hole filling"! I was melting the base metals and the rod. Thus that is welding. For help with brazing techniques here's a good place to start:

http://www.lucasmilhaupt.com/en-US/brazingfundamentals/

RonD2 · Post by **RonD2** » Mon Jul 27, 2015 10:00 pm

Yowza! If I had any brass (and I'm a rookie so I haven't been issued any yet) I'd say there's no mercy in this forum!

Plenty of love though.....

Post by **wesk** » Tue Jul 28, 2015 6:53 am

Not that bad Ron. It's called old school. When the teacher found out you didn't do your homework she would rake you over the coals in class that morning.

jimm · Post by **jimm** » Wed Jul 29, 2015 8:44 am

wesk wrote:J
I just plugged 10 holes in a steel door frame for an antique aircraft using good old fashioned Oxy/acetylene and it took all of 15 minutes. All blind holes and no way to back-up. The right temp, right flame, right motion and filler rod!

That's what I was going to suggest. I find gas welding a lot easier (for me) to control, and the result is filler metal that isn't harder than the base metal like you get with MIG. You have to be careful about the amount of heat, but like Wes said, with the right techniques that is minimized.