Technical How to remove hood pin holes in hood?

First, I'd like to find the guy that mutilated this hood and...., well, you get the idea.

WELD:

Anyhow, the proper way is to weld them up (oxy-acetylene so you can preheat and compensate for the cooling distortion - and although I can do that, I'm not good enough to do that on a hood.)

BONDO:

Make some metal discs the thickness of the hood with about 1/4" over lap, carefully taper both the hood and discs so that the cross-sectional thickness remains the same through the hap joint, and epoxy them from the bottom of the hood.

Then fill the depression from the top with some kind of premium filler or perhaps some of that ultra 3M (crazy sandable) glazing putty.

From the underside which is visible when the hood is open , well, that will ****.

REPLACE:

Bind a new hood. Pray that it get shipped w/o damage (this is basically impossible.) Sell off the old hood.
_________________________

Maybe someone has some Out Of The Box ideas?

Some Crazy thoughts:

• Dual hood ornaments
• Fab some fine SS discs w/o the center hole and install w/the 4 screws
  
• LED turn signal indicators (like some GM had out on the fenders in the 70's)
• Leave the hood pins in (major yuckiness)
• Kill myself (sarcasm)

 

You know your first idea is the only answer, right?
WELD......


Posted using the Full Custom H.A.M.B. App!

 

Mig welder.. Properly done will have no distortion, little or no filler.

 

I would cut a round plug and mig weld it if it were mine. HRP

 

Cut patch panels the size of the inside of the hole and slowly, carefully weld them in place one small tack at a time. Next, grind them smooth, then follow with a light skim coat of filler. Make no attempt to preheat the area with oxy/acetylene.

Also, don't hesitate to ask us for help, there is a **** load of experience hanging around here.

Good luck, -Abone.

 

I'd lead it in a heatbeat. Cut a piece of br*** for backing, clean to bare shiney steel on the inside and tin it. Tin the br***. Drop the br*** on top of the hole and lead it, add a little more lead to the outside and finish. No warpage and the traditional way to fix a hole. If you want to restore then you'd weld a piece in. Big difference.

 

Take it easy grinding, too; so it doesn't overheat and warp

 

Welding is the only correct way, however you didn't say what car this hood is for?
Replace; Might be an option if it's not a $1500 34 Ford hood.
If it's a 64 Chevy pickup and you can find a straight hood off Craigslist for $100 it may be a better approach than welding work especially if your welding skills are not up to the task (and I'm thinking they might not simply from the fact that you're considering bondo plugs, etc.)

 

get a different hood

 

The hood is pretty flat, any form of fusion would produce residual tension and hence distortion. MIG will produce distortion. Expert O-A will produce NO distortion - I'm good but not an expert.

...just thinking about that residual tension: Theoretically should be possible to hammer and dolly the weld to expand it and get back to original shape. I could practice on some totally flat s****.​

However.... using Silicon Bronze MIG wire would be the ticket - much less heat and distortion. I've done this. (some memory huh?) Automakers are doing this now and the stuff is totally compatible with paints and bondo (NOT like br***!) An old welder fabricator turned me on to this stuff. He was really excited about what you could do with so much less heat.

But I never thought of LEAD - definitely out of My Box although I've done this (senility? haha.) Definitely would be the safest road to take. And I like that it would be invisible from the underside too.

But why br*** plugs? I would not want different coefficients of thermal expansion - weather heat cycle cracking?

Also thinking the screw holes can probably be leaded in w/o plugs.
​

ONE DECISION MADE: Will NOT use my BONDO method which I really hated anyway.

I'm going to play with the S-B MIG wire too...

​

I knew You Guys would bury me with advice!

 

One thin mint?
I'd use Oxy-Acet, but depends if you can re-stretch after the weld. Sometimes bracework lurks right behind the welds!

 

Here is the proper way to do it. By the way vote on tech week if you haven't.
http://www.jalopyjournal.com/forum/threads/tech-week-how-to-fill-trim-holes.993379/#post-11190882

 

Patience. Properly fit the plug, leave some gap, about the thickness of your weld wire or less. Position the plug weld so it's clamped in place and in alignment, don't try to hold it. Place 2 tacks. Get the hell away from it, let it cool to the touch. Place 2 more tacks. Let it cool to the touch. Grind back your 4 tacks. Use hammer on dolly, on your tacks for a slight stretch to relieve tension from heat shrinkage. I'm ***uming you can get to both sides of the repair.

Since you have 2 holes, move back and forth. Let your tacks cool. Oh yeah, let your tacks cool.

 

I vote for lead also. But use a copper plate, not br***, to back up the underside. Lead is easy to work with especially on a flat horizontal surface. Less heat used and less chance of warping. Used it on my 50 to french my head and tail lights.

 

do it once, do it right and weld it. hood pin holes can not be that big, there is no reason a person reasonably skilled with a mig could not patch those holes with no distortion and no mud at all.

 

Not admitting that I would do this but... You could back it with copper or br*** and just weld the hole with a mig. It should only be about a 9/16" hole.

 

using a welders s**** I would spot mig it , as long as you overlap the spots real good the s**** should pull the heat out and not throw it in the sheet metal , and if your a little afraid , punch a bunch of holes in some junk metal and practice till you get the hang of it . this way it will not cost you anything but time and materials . some of the best welders I know still practice some welds that are not normally used to keep sharp on them .

 

I'm not sure how big your holes are but if they are small you can just MIG them. Get an old s**** piece of copper pipe, beat the last 2in flat with a hammer or vise, and make yourself a little weld backer that you can hold or clamp in place while you weld up the holes.

 

I had to do this today on a roof. Had about an 1/8 inch hole that looked like an alignment hole that was under a factory leaded joint. Had to remove the lead for another repair. Took a piece of heavy solid copper wire, for electrical service to the building. Beat one end flat to act as a s****, snaked it in behind. Layed my tacks half on the existing and drug them onto the s****, blew air on each weld then a light grind, cooled again, got it tacked all around, then 1 big rosette style weld in the middle. Slow grinding, some filing and it finished to surface, no apparent warpage blocking across it with primer. Torch angle plays a big part of these type of fill welds.

 

Hammer weld it

 

"One theen mint?" Haha I recognize the quote and you have solved the riddle of my screen name!

First question is, What is a Hammer Weld?

...back to reply:

The underside of the hood is free and clear so a few hammer taps would be easy as would backing with copper - I have all kinds of copper backing material.

Actually a hybrid method would be to tack the plug in and then lead. The little sheet metal screw holes, lead also. (When body guys would pull a dent with a sheet metal screw in a slide hammer, leading up those holes was totally acceptable. however, there was no concern how things look on the back side.)

I guess with the hood and holes in clear view when open, you really can't argue with a proper weld.

No matter what, Practice, Practice, Practice before I attempting any kind of welding.

OK, I'm going to read the Trim Hole thread.... (my bad)

OK, read the trim hole thread.

My hood has some gentle curvature in one direction, so basically its cylindrical. The example in the article had tons of curvature which makes it a lot easier.

I like the idea of hammering the plug to expand it and make it tight in the hole. If this can be achieved, it can be oxy-acetylene welded with NO filler rod (maybe TIG to ???) and THE RULE OF DISTORTION IS: MORE ROD, MORE DISTORTION. So No rod would be the ultimate.

I confess it would be so easy to lead in the tight plug.

I am thinking about just welding it. Since the back is totally unobstructed, any welding residual tension can be relieved with a little hammering. And my Smith AW1 would do a great job.​

 

Ah yes, "Hammer Welding"

This is the First Method of dealing with sheet metal weld distortion. Works nicely. I've done it.

But then there is the Second Method (and "final" and best method in my book because if mastered, you can produce a distortion free weld with no access to the back side of the panel):

If you have curvature that has no "locks" in it - meaning if you heat the area, it will become more concave or convex depending if it is an in-ee or out-ee - you can torch weld it without any distortion as follows:

You preheat a ring around the weld area to cause the sheet to "bulge."

This bulge puts the weld area in tension so that when you begin the weld, the metal yields due to this tension - with skill, this amount of yielding is the same amount of hammering you use to expand the residual tension weld.

When done properly, when the area cools down, it returns exactly to the proper shape (i.e., without distortion!)

When I was a mere sprout, I put 137 hours of gas welding in a 1974 Datsun B210 and my skills evolved into the Second Method with no instruction from anyone or any book. Of course my skills are quite "rusty" but they approximate way to gauge the amount of preheat is to cause a bulge in the metal that does not increase as you make the weld. That is a rough rule of thumb.

NOTE: regarding Locks: It is possible to heat the area and hammer out the lock.in some cases. Then you can bring the bulge back by shrinking. A tedious process and tricky when its concave because if convex, you can apply hammer to it to help it along. But to pound it more convex, you have to get the hammer behind it. In some cases you can wedge a pry bar behind and heat orange so you can stretch out with bar. Very nasty business.

This is O/A welding at the highest level and will be a Lost Art in one more generation.

I knew an old German guy who was a certified aircraft welder that worked miracles with O/A. He would do large weld repairs and fabs and use a file to "smooth out" his work. No Bondo. No lead. No glazing putty. In his world, if the torch popped, you had to cut the entire area out and weld in a plug - that was for aircraft. It was back when you gas welded 4340 tubing.​

 

But Sir, it is waayfaah thinn.

 

The curvature is so minimal with a hole of that size that it might as well be flat. When I tig a screw hole shut with no plug I keep the temp low with the pedal and play the heat into the rod creating a blob that sits mostly on top and then I give a step to the pedal till it flows in and back off immediately to let the argon cool it. One on dolly smack and it is ready for grinding.

 

So you get a blob on the end of the rod, lay it on the hole, and then flow it into the panel?

"Welding" with the silicon bronze, either MIG or TIG (or oxy-acetylene?) would be pretty darn robust, but fusion is always the ultimate.

GimpysHotRods: yeah cl***ic! Knights of Nih, Tarquin Biscuit Barrel, "I think he's pining for the fjords," etc, etc.. (!) Check out the Turbo Encabulator and all its variants.

....

Oh, oh... just checked RockAuto and an aftermarket hood is $105 and shipping is $185 freight. Well, that's why I have welders....

 

I have used br*** in the past,I will never do it again!

It came back to haunt me! HRP

 

Br*** ****s big time with regard to paint and bondo - nothing sticks.

Silicon bronze on the other hand behaves just like steel - so you get the best of both worlds.

 

Instead of creating a puddle and adding the rod to it I start with the rod on the metal to have a ground and play the heat into the rod instead of the base metal creating a small blob on top of the hole. As soon as it is enough to fill the hole crank on the pedal to flow it in then back off as soon as it does. That is the best way I can describe it. If you start with a hole and try to create a puddle you will just end up with a bigger hole. I use .035 rod and a 1/16" ceriated tungsten sharpened to a needle point, a #5 cup and @20 cfh of argon. High amp setting on the welder is usually 48-68 amps when I am welding sheet metal. The key is full penetration without burning through. I hope this explains it so it is understandable. Bring it on over, it will take about an hr. to make it look like nothing ever happened.

 

55willys: Sounds like how I weld up pin holes with oxy-acetylene: I use a big rod, put all the heat into the rod, and then flow it into the hole. If I get the blob the right size and manage my heat properly, it fills the hole just right.