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#1002208 01/27/2014 12:52 AM
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I have a 46 1/2ton with steel rear fenders, my question is... they look like a fat womans thighs.. like cottage cheese, with real small dents anddings all over the tops of them, any idea how to get all that mess straightened out on them without alot of bondo?.....would an english wheel work? there is no rust on them at all

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photo's would help...


Give me ambiguity
or give me something else
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An English wheel used improperly in this scenario may add stretch to the equation. Given the dings and dents you already have, the panel is already stretched at each of these spots, and will need shrinking more than anything. You can use an English wheel to wash over the walnuts, and can be used effectively, but you will need to have minimal pressure and the anvil closely matched to the underside of the panel to lessen any chance of changing the shape. This may involve many changeouts to different radius anvils.

I would suggest checking Amazon or other sources for "The Key to Metal Bumping" to learn off-dolly hammer work. It's a very old book, but a very good resource. A good online source is available via Uncle, here:

http://www.hnsa.org/doc/pdf/metal-body-repair.pdf

Another useful tool is a donut dolly that allows off-dolly repairs but the support at more than one point tends to be more effective.

Here on a flat aluminum door skin:

http://www.garagejournal.com/forum/showpost.php?p=1843066&postcount=247

...here on a simulated roof damage....


http://www.garagejournal.com/forum/showpost.php?p=1638725&postcount=235


....and here on sandblast damage (My theory on measuring was an inaccurate assumption, so be sure to read this one in entirety for the "true story".... This thread also shows good use of a stud puller with shrinking tip.

http://www.garagejournal.com/forum/showthread.php?t=132084



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If it was just a couple spots, which it sounds like it isn't. You could always shrink them by using a gas welding tip and dolly and hammer to shrink them.

John

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I've seen this before when guys have dropped loads of rock into a truck bed. It's worse to fix than hail damage. X2 whitelightnings comment. I wish you patience and luck.


Have you ever noticed that anyone driving slower than you is an idiot and anyone driving faster than you is a maniac? - George Carlin
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'Bolter
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Would a planishing hammer help here?


1951 GMC 1 Ton Flatbed -- It is finally on the road and what a great time I have driving it!
1951 1 Ton Completed


My Chevy Master 4 Door is on the Road!
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It may smooth things, but given dents and dings, the fenders are stretched as it is. Planishing will add more stretch, unless you have some fancy non-metallic dies.. and easy on the pressure..

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They do make what they call shrinking disks anymore. I don't really understand how they work, never used one. The disk is sort of "corrugated" around the edge.
Another thing they sell is a body hammer with a head on it that "turns" when you strike the metal. It has like a spiral pattern on the face of it. Never used one of those either, so don't know how well it would work either.

John

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I have seen videos on YouTube of the use of a shrinking disc on a big electric grinder on an AD fender. He said he can work a fender as bad as what yours sounds like to the point that NO filler was required. Its worth a watch.


1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
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I've used several of the shrinking discs in the past to smooth
high crown compound curves such as found on fenders. Here's an
AD rear fender that was quite uneven to start with:
http://www.pbase.com/dennygraham/image/122303947
Here it is with only a minimal amount of filler and high build
primer applied:
http://www.pbase.com/dennygraham/image/114605009

The shrinking disc is used to uniformly heat up a
large area by friction, which is then water quenched
to shrink it. Since this does not generate a lot of
heat like a torch does, it requires that you repeat
it many times to take the high spots down. But it does
work.
To shrink a large area down that has many dings using the
off dolly hammer technique requires a 'LOT' of practice. One
phase of the hammer and dolly technique is using a
body file to dress a few thousands off the high
spots. This always bothered me because it's easy to
thin down the material in the area the you are
working unless you are very patient with the
hammer and dolly end of it.
The shrinking disc does not require that you remove any material
so the panel is still of uniform thickness when you finish working it.

Denny Graham
Knee deep in snow north of Sandwich, IL

Last edited by Denny Graham; 01/28/2014 2:45 PM.

Denny G
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Hoozat....You have a lot of professionals here, Caso, MP&C, MartinSr and Sevtchevelle all with a wealth of knowledge and experience and some with videos or Youtubes. A search will bring many hours enjoyment and learning. They have all been a help to me and I enjoy bodywork and been putzing with vehicles for over 40 plus years. Pictures help. Bolters listen and help and will tell you hands on is the best teacher. Have fun and good luck
Dan

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My fender on my truck look like that, I'm sending them over to Denny's for refinishing.....

John

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Denny, that is some fiiiiiiine work you did on that fender!!!

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Yep, I agree. Wait, my ego got the best of me there Mick, let me
back up. Yes it turned out pretty good, only problem is it took
me a month to get it looking that way without using a can of
Bondo to smooth things over. I hadn't done any of that hammer
and dolly work for many decades so that rear fender served as
a refresher in panel beating that me pop taught had me over
50 years ago. Just a few dabs of plastic filler near the
bottom edges which needed some tears welded shut.
A little bit of lead also at the toe after welding, where It
mounts to the running board and was torn. In an area like that
where there is more stress I like to use lead, just because I
feel that the molecular bond makes for a stronger interface of
the filler and parent metal.
DG

Last edited by Denny Graham; 01/28/2014 11:02 PM.

Denny G
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Denny, nice repair on the rear fender, I think using the shrinking disc works best on a crowned panel such as that fender to allow good access to the high spots, and your efforts show how well it works.

On the body file (vixen) you referred to, I would suggest to ease up on the pressure. You want to glide across the panel enough to remove the guide coat and show the high spots. It's not about removing metal.

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Not into giving lessons like you are Robert, just trying to show
the original poster hozat that with enough time and patience
even an amateur can work those dings and dents out.
As far as removing metal with a file, take a peak at some of Ron
Covell's videos where he's removing metal from the high spots
then working the metal to level it. I'd say he's pretty close
to the top of the pile when you talk about modern day metal
bumpers. It might only be a few thousands that he's removing
but when your working with a 1/16" or less I don't want to take
any at all.
But as I said earlier, I don't like and I don't use a vixen file
for anything other than removing some filler, be it lead or
plastic that the cheese grater won't touch.
If you look at the lumps and bumps on that rear fender you can
see the guide coat that I used to bring out the high spots.
Those I worked till they were close then used the shrinking
disc to blend the whole area, no filing.
I had a similar mess on a front fender where a previous mechanic
had used a ballpeen hammer to ding out a dent then had tried to
level it with plastic. Looked like the bottom of an egg carton
when I'd removed the paint and plastic:
http://www.pbase.com/dennygraham/image/138317741
I worked this out with hammer and dolly then finished shrinking
and smoothing it with the disc.
http://www.pbase.com/dennygraham/image/138317748
Again, no file, just guide coat and shooting board to highlight
the hills and valleys when I got close.

Denny Graham
Sandwich, IL


Denny G
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I rarely use the vixen myself, mainly because of the higher crowns normally encountered, and they don't tend to match all that well across the panel consistently. I'd rather use a flexible sander that conforms better, and as you suggest, less chance of metal removal. I agree that when you hit the metal, it's time to stop and do a bit more bumping or shrinking. I had read the pressure applied deal as a response on one of the metal shaping sites where someone raised concern of loss of panel thickness. IMO the vixen should not be used until the panel is to a state that the defects are difficult to see or feel, so unless you are looking for pure metal finishing with no filler, most can get by without it, exactly as you have shown. I rarely use the method myself, just thought I'd pass it along as food for thought if someone may want to try it. wink

On the giving lessons topic, your rear fender would have been a good video candidate for the shrinking disc, and your results would make anyone proud.. The few videos that I have done I try to keep less than 3-5 minutes, mainly due to file size before I convert the video. I can see a disc shrinking tutorial exceeding that unless one only focuses on a couple spots or extensively uses video editing. I seem to have better luck with hammers than trying to edit videos. grin

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Denny,
Great work! You have been blessed with talent. I enjoyed looking at the photo's thanks for posting.
What material did you use to make your anti-squeak pieces?
Have a great day.
Harold


Harold
Is a restoration ever finished?
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30# roofing paper Harold, same thing that the vendors are
going to be selling you.

There are several videos of the shrinking disc in use that were
posted by the guys that make and sell them. I've bought several
from different guys and if I remember correctly they all had a
video on the use of them.
One that I bought was not made very straight and it wanted to
hop all over the panel but he sent me another that was ok.

Here's one of those videos that show the disc for those that
have never seen it used:



DG


Denny G
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Ill have to post some pics of my fenders to show what they look like.....it was an old farmtruck, and used as one


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