shrinking a panel.

[ari666]

so i butchered a patch on my boot a while ago (cos' im a hack and dont know WTF i am doing) and now i need to shrink back about half of my boot to stop it from 'oil-canning'

i watched my 'mate' shrinking back a couple of spots on guards/doors etc and i think i get the idea. he made it look easy, but them problem is the inner boot skin is completely sealed off. unlike a a commodore where the skeleton has loads of access to the outer boot skin, this is like another panel.

now the plan is to cut a large section of the inner skin off, shrink back the outer and weld it back on. i would like to know if there is an easier way. and if not some tips on doing it properley would be much appreciated. the stages i am thinking so far are:

1. cut inner off
2. find the highs and lows, and flatten as much out as possible
3. using the edge of a crow bar and finishing hammer, strech a little peak into the point that needs to be shrink
4. hit it with the oxy, get a 10 cent piece size cherry red center
5. finishing hammer and dolly it flat
6. cold water on a rag

is that right? i tried just using the oxy on the highs to heat up a spot then a wet rag but it seemed to make it worse.

also how do i know 100% the spot that needs to be shrink?

thanks

 

[wildss]

what exactly have you done to the boot?

 

[ari666]

replaced a square patch of rust and got it a bit too hot in the corner.

 

[383 hatch]

**** Ari, i would love to help but it's a bit of an art and takes a fair bit of practice to get the hang of. Honestly, knowing where to shrink is the hardest part to master. Once you know where to shrink, the shrinking itself is fairly straight forward really.

1) Hit it with the oxy, keep the heat area small, get it to a cherry red (i normally keep it to about a 5c piece size)
2) Hammer and dolly the heated spot till its flat
3) Quench with a damp rag

Keep repeating the process till it's right.

Just heating & quenching will make it worse, you need to hammer & dolly it to shrink the steel. What i will tell you is that you need to work quick, so you really need a stand for the oxy so you can put it down quick or have someone do the heating for you so you can hammer and dolly while the panel is still hot. If it goes cold before you planish it, it won't work properly.

 

[ari666]

yah i was the guy holding the oxy and wet rag for my mate. seemd to work really well. i might have to enlist the services of my missus

i think im just gonna wing it, and if i f' it up any further i found a new boot for 300 bucks, so will start over.

 

[VKCOMMO]

yah i was the guy holding the oxy and wet rag for my mate. seemd to work really well. i might have to enlist the services of my missus

i think im just gonna wing it, and if i f' it up any further i found a new boot for 300 bucks, so will start over.

WHy dont you ask your mate to do it? LOL

 

[wildss]

if you can get your hands on a dent puller gun (the copper nail type) you could hold parts of it while you heat and hammer down.
will be alot better than cutting the frame out imo.

p.s ive used just the head of the gun with no pin to heat spots on panels before