Sheet metal repair help needed

[ebinmaine 63,333]

The area in the picture below is on the side of the hood right next to the muffler on a C Series.

It's badly dented in as well as horribly pitted.

We've been working with hammer and dolly to push out the dent.

Once the body line is back fairly close to where it needs to be we will need to coat this area.

With what?

We have some Bondo brand body filler.

My thought was to remove as much paint as possible even though we might not be able to get all the way down into those pits. Skim coat the Bondo and sand it off a few times until we get back to a flat finish.

After that's done we will use filler primer on the whole Hood surface and give it a final sanding.

 

 

Am I headed down the right path?

What would you do different?

 

Is the Bondo filler going to stay in those holes and possibly near the heat of a muffler okay?

 

 

 

[WHX?? 46,933]

Dan @Achto ? 

[Pullstart 59,859]

I’m gonna go ahead and assume that steel is stretched.  If the sheet metal is flattened completely, it’ll likely curve the nose of the grille, or attempt to.  Kind of a tin car effect in the metal now.  I’m thinking the steel needs to be shrunk or cut and welded..

[Handy Don 10,658]

Following with interest 

[Achto 26,611]

54 minutes ago, ebinmaine said:

Am I headed down the right path?

What would you do different?

 

Sounds like you are on the right path to me.

When you get ready to apply body filler you will want bare metal and a real good mechanical scratch in the metal 36 to 40 grit. This will give the filler some thing to hold on to. Avoid putting filler over paint, the results of this is rarely satisfactory. Small little pits with paint in them should not be a huge deal but try to dig them out best as you can, a Dremel works good for cleaning them out.

 

Filler should be fine with the heat as long as it is not extreme. 1/2" to 3/4" air space between the side of the exhaust and filler is adequate.

Edited December 15, 2022 by Achto

[rmaynard 14,932]

I'm going to agree with Kevin about the need to shrink the metal. Use a shrinking hammer.

YouTube a video on how to do it. First though, remove all the paint in that area before working the metal. After you have flattened it, a good quality filler should take care of the pits. Just make sure that when reassembling you keep a 1" air gap between the muffler and the hood.

 

EDIT: Looks like Dan beat me to it.

Edited December 16, 2022 by rmaynard

[ri702bill 7,382]

1 hour ago, ebinmaine said:

side of the hood right next to the muffler on a C Series.

I too agree that area may need to be shrunken - particularly if it acts like the bottom of an old oil can when you push on it.

There are 2 good methods to shrink a portion of metal - BOTH require a bit of practice to get the desired result.

First - the shrinking hammer - done cold, works well - best suited for small areas.

Second - localized heat from a torch, followed immediately by placing a rag saturated with water FROM the side you wish to shrink it to. Old bodyman trick. Repeat as necessary.

 

That area of the hood sees the most heat from the exhaust. You need to choose a filler that can withstand repeated heating and cooling. Regardless of the material chosen, keep the thickness to a bare minimum.

 

I have had good success using 2 part JB Weld where heating and cooling were an issue. Repaired a porous 8HP Kohler block on the C81 in the thin area at the rear - there is a mold parting line there that was annoying porous. Three years now, no leak.

I bought four OE Ford silver colored alluminum rims in 2015 for winter tires on my Focus. Two were perfect, two had a couple of small chips on the rim edge or spoke. Gouged out the chip areas, patched with JB and repainted all four.

 

 

Edited December 15, 2022 by ri702bill

[ebinmaine 63,333]

[ri702bill 7,382]

The one that looks like a meat tenderizer is the shrinking hammer - try it on a scrap piece first.

[ebinmaine 63,333]

9 minutes ago, ri702bill said:

The one that looks like a meat tenderizer is the shrinking hammer - try it on a scrap piece first.

Scrap piece of metal or a scrap piece of meat?

 

 

 

 

 

You have to admit that's a legitimate question........ 

[ri702bill 7,382]

2 minutes ago, ebinmaine said:

Scrap piece of metal or a scrap piece of meat?

 

 

 

 

 

You have to admit that's a legitimate question........ 

Valid question. Try it on the metal first. If neither you or Trina get the hang of it - move onto the meat !!

Remember where it came from  - you may wish to be selective before using it on anything you would eat..... (WOW - was that P.C. or what ??)

[pacer 3,160]

As usual you're getting lotsa good info here   - I'll just add a couple that havent been mentioned.

 

1st, before you start with hammer remove all that old paint so you wont have it in those little 'dimples' to worry with later. Next get some type of sand blaster, even if its only one of those hand held thingys, not only will it remove that old paint in the dimples, but also any rust, and leave you with a slightly 'roughened' surface that filler and paint will stick to much better.

[RandyLittrell 3,827]

It's fairly think metal and I think you can work it pretty easy. Use the shrinking hammer and instead of the metal dolly, use a piece of 2x4. It will let you shrink it easier in my experience. Work it before you removed paint so you can feel it with your hand easier. Use a rag under your hand so it slides easy. When you get it close, just dust a little black rattle can on it and after it dries just a bit, dry block it with 150 or something similar. That will show your low spots. Rinse and repeat till its close, then remove paint. Buy some quality auto body filler, not bondo brand in my opinion. The new fillers really only need 80 grit to bite well and they make thin coat fillers that only need about 150. This is what I was doing when I quit working a few years ago, the newest fillers are so easy to work with over the old kind and really cheap stuff. 

 

Call me if you need! 

 

 

Randy

[8ntruck 6,419]

Years ago I bought a spot sandblaster from Eastwood.  It is a siphon gun that draws same from a fabric filter bag mounted on the gun.  It also has a 'rubber' hood that seals to the work surface and directs the exhaust and used sand back into the filter bag.

 

Does a good job of digging rust out of pitted material.  Only drawback is that it only cleans a 1" diameter spot at a time.

 

It would be perfect for your project.

 

I'm also going to agree with the comments about shrinking the metal.  Along with the shrinking hammer and torch methods, somebody makes a shrinking wheel for an angle grinder.  The shrinking wheel is a radially corrugated metal disk that you spin against the area you want shrunk.  Friction makes heat, heat helps shrink the workpiece.

 

Disclaimer - I've never used one of these things.  If you opt for this method, read and follow the stinking directions.

Edited December 15, 2022 by 8ntruck

[Handy Don 10,658]

3 hours ago, Achto said:

Small little pits with paint in them ... try to dig them out best as you can

For small areas like pits and embossed lettering, I've used "gum out" to soften paint then a small wire wheel on a Dremel (ventilated area, of course!)

[squonk 39,012]

What's a tractor with out a small dent or 2. Gives it "character"  You can fill the pits with "High Heat " JB Weld.

Edited December 15, 2022 by squonk

[ebinmaine 63,333]

5 minutes ago, squonk said:

What's a tractor with out a small dent or 2. Gives it "character"  

On no worries Mike. It'll still have plenty.  

[D_Mac 8,252]

Seems every C series has that same problem. Its the heat coming off the muffler that to that same area in just about every one I seen. See if you can make a heat shield or you will have the same issues down the road.

[ebinmaine 63,333]

32 minutes ago, D_Mac said:

Seems every C series has that same problem. Its the heat coming off the muffler that to that same area in just about every one I seen. See if you can make a heat shield or you will have the same issues down the road.

Stack would solve it too.  🙂

 

This one won't have a stack though.  

 

I've seen diagrams or pics of added on heat shields somewhere on here.  

 

Still not sure what I'll do for a muffler.  

Might go right back to the Gravely style that was on it.  

Pointed diagonally forward and down.  

 

[Lee1977 6,259]

On 12/15/2022 at 7:55 AM, Pullstart said:

I’m gonna go ahead and assume that steel is stretched.  If the sheet metal is flattened completely, it’ll likely curve the nose of the grille, or attempt to.  Kind of a tin car effect in the metal now.  I’m thinking the steel needs to be shrunk or cut and welded..

I don't think it's bent enough to stretch the metal. I have used a inch thick rubber foam pad on the concrete floor and a rubber hammer on similar dents. 

[rmaynard 14,932]

My original 1977 B-100 had it's original muffler when I acquired it in 1993. I replaced the muffler only once with an OEM Nelson muffler in 2005. I never had any issue with heat deforming the hood.  Here is a picture taken in 2009 showing how when the proper muffler is installed properly, there is about a 1" air gap between the muffler and the hood. I guess the engineers at Wheel Horse knew what they were doing.

 

 

[ebinmaine 63,333]

1 hour ago, rmaynard said:

My original 1977 B-100 had it's original muffler when I acquired it in 1993. I replaced the muffler only once with an OEM Nelson muffler in 2005. I never had any issue with heat deforming the hood.  Here is a picture taken in 2009 showing how when the proper muffler is installed properly, there is about a 1" air gap between the muffler and the hood. I guess the engineers at Wheel Horse knew what they were doing.

 

 

 

 

I've seen several where folks have tried to put the larger diameter can muffler that would have been on a black hood, onto an older C Series like mine. Those have far less clearance. MAYBE 1/4".   

 

This particular hood that Trina and I are working on right now appears that it was probably cooked a lot more than once by an improper muffler installation of a previous owner but also, I think it's been bashed on that side because it's in a fair amount.   

 

[rmaynard 14,932]

As far as I know, the black hoods used the same muffler. I bought a muffler from a C-105 that was identical to the B-100 muffler. It is a matter of how it is installed. When properly positioned, the muffler is about 1/4" from the air cleaner cover.

 

[Handy Don 10,658]

8 minutes ago, ebinmaine said:

cooked ... bashed

Glad it'll be looked after by more humane owners now! 👍

[ebinmaine 63,333]

2 minutes ago, rmaynard said:

black hoods used the same muffler

 

The mufflers up to the mid 70s were a smaller diameter can than they were around 1978 or 80 up to 1982 or 3.

 

My apologies for the vagueosity of the info there.  

 

I believe the general shape and length and angles of the pipes were similar or identical.

 

Outer diameter was around 2.75 or 2.95 for the smaller ones and on the larger style can the diameter was more like 3.5".  

 

We've had at least a couple of the earlier C Series come through our shop that had the larger diameter can.   They were VERY close to the hood.   Paint was burnt right off for a distance of several inches up and down the hood, near the muffler.

 

It's also possible that the pipe nipple sticking out of the engine had been incorrectly changed or cut.