Filling small holes without welding

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Bennyt

Full Access Member
Joined
May 17, 2019
Posts
1,222
Reaction score
1,927
Location
Surprise
First Name
Ben
Truck Year
1977
Truck Model
C10
Engine Size
350
I would only weld, everything else is a compromise and cross your fingers it is going to last.

I use these plugs from Speedway and others for holes larger than 1/4". Unibit to size and a magnet to hold. Saves a lot of time. Available in various diameters and gauges.

You must be registered for see images attach
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
30,616
Reaction score
28,852
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
If the holes are actually only 1/8 or 3/16-ish in size, it's pretty easy to weld those up.

It was mentioned earlier, the possibility of using fiberglass body filler, along with dimpling the steel down. Imho, it's the next best thing to welding. Simply grind the metal a bit, ding it down, feather the surrounding steel with 80 Grit on a DA, then apply the Duraglass. Sand the Duraglass down a little "too far" and skim coat with a polyester glaze.

It may be considered a little bit "hack" this day and age, but it does work very well.
 

Doppleganger

Full Access Member
Joined
May 24, 2019
Posts
12,816
Reaction score
59,448
Location
OH-MI: Just like it sounds
First Name
Chris
Truck Year
1985
Truck Model
K20
Engine Size
5.7
I used a stud welder. Stud is tapered on the end - 1/16 to 3/16. Holes are 1/8 (2/16). Set the stud in the hole and lit it up. Snipped the stem, ground the nub down. Nice little welded copper plugs.

Still have 2 large holes on the firewall - ground down some fender washers to make perfect plugs - now gotta get it tacked in. lmao - will never happen around here. Maybe I can get creative with panel adhesive?
 

Oldbear42

Supporting Member
Supporting Member
Joined
Feb 15, 2024
Posts
197
Reaction score
510
Location
Linden, Alberta, Canada
First Name
Shaine
Truck Year
1981
Truck Model
C20 LWB Scottsdale
Engine Size
350
I have a redneck copper spoon for welding holes in sheet metal. It's a 1" copper pipe flattened and folded, then attached to a handle. I also have the spotweld clamp version (store-bought). It keeps the weld flatter and gives a backing and heatsink to avoid blowouts. I need to take the copper to my blacksmith friend so we can heat and hammer the layers together better - but that is a winter project/visit. The picture is a store-bought version of the spoon, but you get the idea (mine is at home).
 

Attachments

  • xwelding-spoon.jpg.pagespeed.ic.Gll2Epuayu.jpg
    xwelding-spoon.jpg.pagespeed.ic.Gll2Epuayu.jpg
    64.4 KB · Views: 14
  • 23230_1.jpg
    23230_1.jpg
    26.9 KB · Views: 17

CalSgt

Full Access Member
Joined
Oct 3, 2021
Posts
1,732
Reaction score
3,905
Location
CA
First Name
Casey
Truck Year
1980
Truck Model
Chevy K-10 Custom Deluxe
Engine Size
350
Use some copper or aluminum to back the area up, works as a heat sink and helps with bridging a gap.

Larger holes a Whitney Jensen hand punch or equivalent to make little discs to weld in:
You must be registered for see images attach
Same ^^^^
 

backyardgarage

Full Access Member
Joined
Nov 14, 2018
Posts
54
Reaction score
134
Location
Ocala
First Name
Mike
Truck Year
1988
Truck Model
K-5
Engine Size
350
Small holes without welding I use All Metal or Dyna Glass. Both are body filler impregnated with either metal or fiberglass. For the most part the are water resistant, which regular body filler is not.
If I weld, I use a Miller 211 turned way down and a 24 wire with a peice of copper behind it and use compressed air or a wet rag to keep the metal cool
 

59840Surfer

Full Access Member
Joined
Oct 8, 2020
Posts
212
Reaction score
336
Location
Montana
First Name
Joe
Truck Year
1986
Truck Model
K5
Engine Size
350 Stroker to 383 with a 400 crank, Crane Cam, Q-Jet, single 3.5" exhaust..
A friend of mine came by about a year ago - he'd been welding 40+yrs - and couldn't stop from turning small holes into bigger ones on the firewall using a Miller 110 welder I had - found out later the welder's wiring was bad so he (apparently) couldn't turn it down enough. He died in a house fire last winter, so I dont know anyone locally at this point who can even weld.

Eastwood sells a solder 'kit' for a brazillian dollars - I only need to fill about 20 holes, most all 1/8 (maybe smaller). Cab is going to be stripped (again) Monday AM so would kind of like to get them filled beforehand. Maybe JB Weld? Dunno. Its always something.
I like watching Bondo Billy --- here he's flux-core welding a gap-slot -- and it is a decent weld process.

I've seen him chase rust holes in much the same way --- and they always turn out good - I still like to think he's shooting some panel wax on the inside after he completes the welding and painting is done ...

xc_hide_links_from_guests_guests_error_hide_media
 

YakkoWarner

Full Access Member
Joined
May 29, 2024
Posts
188
Reaction score
252
Location
Central Texas
First Name
Wolf
Truck Year
1989
Truck Model
R2500 Suburban
Engine Size
454
I like watching Bondo Billy --- here he's flux-core welding a gap-slot -- and it is a decent weld process.

I've seen him chase rust holes in much the same way --- and they always turn out good - I still like to think he's shooting some panel wax on the inside after he completes the welding and painting is done ...

xc_hide_links_from_guests_guests_error_hide_media

I had to do something similar with a small section of the floor area of an MGB up under the throttle pedal - a very difficult spot to access for cutting out and replacing (and above where the replacement floor pans went up to) - pinholed but not completely gone. I opted to work across the pinholes with a Hobart 140 turned down low, I'm nowhere near as good as the guy in the video so I spent a lot more time chasing gaps and burn-thrus. When I was done I could grind it mostly smooth and shine a light from below without seeing any more holes, so primed and painted and called it good for now. The same area on the passenger side needed a cutout/replace because it was far worse, and the entire floor pans on both sides were mostly gone so they got replaced.

A TIG might be easier to control in that situation, but I havn't gotten mine set up to start practicing with yet.
 

Radiohead

That guy on the Columbia
Joined
Mar 17, 2022
Posts
2,488
Reaction score
8,119
Location
Low Earth Orbit where it's safer
First Name
Eric
Truck Year
MCMLXXIX
Truck Model
C-20 Silverado Camper Special
Engine Size
454 crazy cubes, or 7.4 luscious litres
Use some copper or aluminum to back the area up, works as a heat sink and helps with bridging a gap.

Larger holes a Whitney Jensen hand punch or equivalent to make little discs to weld in:
You must be registered for see images attach
I have a brass, or maybe bronze, slug around here for that exact job, backing up the hole. I'm in the welder up camp.
 

1977banana

Junior Member
Joined
Jul 7, 2024
Posts
14
Reaction score
29
Location
canada
First Name
mark
Truck Year
1977
Truck Model
k10
Engine Size
350
I have to respectfully disagree with one of the comments a ways back here. These trucks (square-body) do NOT have thick metal lol. I have measured a lot of it at 24 gauge, especially on crowns and corners the panels are really inconsistent. You have to be careful on blowing through it. In some cases the patches are way thicker than the parent material which is not usually the case in patch panels. i think the last models you could label as thick were the 67-72 years. I remember a buddy with a 61 and he was mad and hit the side of the box with a hammer and it did not dent, so those were truly thick.
 

Doppleganger

Full Access Member
Joined
May 24, 2019
Posts
12,816
Reaction score
59,448
Location
OH-MI: Just like it sounds
First Name
Chris
Truck Year
1985
Truck Model
K20
Engine Size
5.7
I have to respectfully disagree with one of the comments a ways back here. These trucks (square-body) do NOT have thick metal lol. I have measured a lot of it at 24 gauge, especially on crowns and corners the panels are really inconsistent. You have to be careful on blowing through it. In some cases the patches are way thicker than the parent material which is not usually the case in patch panels. i think the last models you could label as thick were the 67-72 years. I remember a buddy with a 61 and he was mad and hit the side of the box with a hammer and it did not dent, so those were truly thick.
I measured mine at .043 .....which is 19 ga. Its hard enough to buff a pop can let alone patch one with heat involved.

Only thinner steel I ever messed with was a shop I worked at that stamped Honduh rear quarters, which was 22 ga (<.030). We had the presses turned down as low as they would go and it still rippled and (literally) tore.
 

1977banana

Junior Member
Joined
Jul 7, 2024
Posts
14
Reaction score
29
Location
canada
First Name
mark
Truck Year
1977
Truck Model
k10
Engine Size
350
What I measured was some un-rusted sheet metal on my 1977 at 24 ga. When I cut away the rusty cab corner areas and got to unrusted metal where the join would be welded. The replacement cab corners (aftermarket) measured 19 ga. and the original was 22-24 ga. which I thought was odd. I expected the original to be as thick or thicker. The cowl sides and upper rockers were also very thin and actually rusted through from the inside out on the upper side not the bottom which was also odd. Maybe quality control on the steel chosen was lacking the week my truck was built, and they ran through some wrong gauge steel through the presses lol. Stamping Honda parts Monday then Chevy truck parts Tuesday without changing steel thickness? lol.
 

Latest posts

Forum statistics

Threads
44,414
Posts
957,015
Members
36,741
Latest member
do4410
Top