Advice to pull the dents out of jacking point

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Dave Whittick
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Advice to pull the dents out of jacking point

#1 Post by Dave Whittick » Fri Oct 04, 2019 8:08 pm

Over the years, people have placed floor jacks under the jacking points of my C and dented the crap out of them. They're very solid so I hate to cut them off and replace with aftermarket but the surrounds are pretty much flat. I have a stud gun with a two lb slide hammer but it's not enough to get any movement. What have you used to pull out your damaged jack point surrounds?
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Last edited by Dave Whittick on Fri Oct 04, 2019 8:59 pm, edited 1 time in total.

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Re: Advice to pull the dents out of jacking point

#2 Post by Phil Planck » Fri Oct 04, 2019 8:40 pm

A picture might help.
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Re: Advice to pull the dents out of jacking point

#3 Post by Martin Benade » Fri Oct 04, 2019 9:28 pm

A factory apprentice must have welded that tube. He didn’t get it hot enough! You can weld tabs to the dented area, put a clamp on it, and yank down with a heavier slide hammer. It won’t be easy but a skilled body worker could get it pretty nice that way.

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Re: Advice to pull the dents out of jacking point

#4 Post by Martin Benade » Fri Oct 04, 2019 9:31 pm

That looks totally rust free! It took 25 years to get my car that way.

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Re: Advice to pull the dents out of jacking point

#5 Post by Dave Whittick » Fri Oct 04, 2019 10:36 pm

Martin Benade wrote:
Fri Oct 04, 2019 9:31 pm
That looks totally rust free! It took 25 years to get my car that way.
Ya, it’s a really clean car. It’s a good one restore as my first. It was nice to not find any drama under the 4 or 5 resprays.

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Re: Advice to pull the dents out of jacking point

#6 Post by Phil Planck » Sat Oct 05, 2019 10:02 am

Dave
Can you show on above pic where you put the stud/s?
That can be repaired, but you have to start at the edges of the dent and work your way to the deepest part. The age old advice is last in, first out. This will be a slow process and require quite a few studs. There are some clever tools out there for leveraging studs instead of using a slide hammer. They give you more precise control.
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Re: Advice to pull the dents out of jacking point

#7 Post by Phil Planck » Sat Oct 05, 2019 10:07 am

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Re: Advice to pull the dents out of jacking point

#8 Post by Vincent Gillespie » Sat Oct 05, 2019 6:43 pm

I'm by no means an expert on this, far from it in fact, but it looks like, on top of the years of use, these jacking points were pretty 'basic' from day one and now your car is stripped to bare metal? If this is the case why not carefully drill out the spot welds, remove the jacking points entirely, then you can really get at it from all sides/angles to sort out the dents/dinks/holes and whatever else is there, then plug/spot weld them back. Under all the modern coatings you will use they will look exactly as bucolic as they were under the wonderful rustproofing used by factory on day one. You will have kept originality and no one will be the wiser unless you wish to tell them.

Hope this is helpful.
V
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Re: Advice to pull the dents out of jacking point

#9 Post by Phil Planck » Sat Oct 05, 2019 7:06 pm

Or, you could break open the middle seam welds and get a hooked tool in to help pull the metal down.
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Re: Advice to pull the dents out of jacking point

#10 Post by Martin Benade » Sat Oct 05, 2019 7:28 pm

I would say my method or removal and straightening are the two best bets here.

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Re: Advice to pull the dents out of jacking point

#11 Post by John Brooks » Sun Oct 06, 2019 1:46 am

You are going to need to drill out the spot welds, remove the jack post. Then you can repair it or get a new one. Then plug weld it back in place. Sounds scary but it's probably 2-3 hours work,

I would clean it well, maybe a overnight in evaprorust, the use a weld through primer and epoxy paint. Mask off 3/4" of primer when the plug welds will go, before apply the top coat. Weld it back on and the prime and paint, undercoat. Sound complicated but it's doable.
Some examples here
https://www.abcgt.com/new-forum/forum/m ... n-projects
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Re: Advice to pull the dents out of jacking point

#12 Post by Don Gale » Sun Oct 06, 2019 12:04 pm

You could use the spider from a harmonic balancer puller with 3 carriage bolts in the corners and weld a nut to the center of the dent and wrench on it. Probably an iterative process cutting off the nut and repeating at logical locations. In the end, it's still going to need bondo.

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Re: Advice to pull the dents out of jacking point

#13 Post by Dave Whittick » Mon Oct 07, 2019 8:36 am

Vincent Gillespie wrote:
Sat Oct 05, 2019 6:43 pm
I'm by no means an expert on this, far from it in fact, but it looks like, on top of the years of use, these jacking points were pretty 'basic' from day one and now your car is stripped to bare metal? If this is the case why not carefully drill out the spot welds, remove the jacking points entirely, then you can really get at it from all sides/angles to sort out the dents/dinks/holes and whatever else is there, then plug/spot weld them back. Under all the modern coatings you will use they will look exactly as bucolic as they were under the wonderful rustproofing used by factory on day one. You will have kept originality and no one will be the wiser unless you wish to tell them.

Hope this is helpful.
V
I did consider this but access to the top spot welds is really limited because the rockers are in the way. My smallest right angle drill can't fit in there to drill out the original welds. Also prevents nice welding afterwards when I want to reinstall. If my rockers were soft, it would be a no brainer to repair the jacking points while I have good access. My rockers are flawless so I don't want to disturb them. Thanks for the suggestion.

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Re: Advice to pull the dents out of jacking point

#14 Post by Dave Whittick » Mon Oct 07, 2019 8:43 am

Don Gale wrote:
Sun Oct 06, 2019 12:04 pm
You could use the spider from a harmonic balancer puller with 3 carriage bolts in the corners and weld a nut to the center of the dent and wrench on it. Probably an iterative process cutting off the nut and repeating at logical locations. In the end, it's still going to need bondo.

Image
Great suggestion! I've got a 7 lbs slide hammer now and I'm going to weld nuts onto it today and take some shots with the heaver hammer. If that doesn't work, I'll try your suggestion. I think it would provide a lot more control than a slide hammer. The only downside I see is having to move the 'pulling nut' to get different pull points I'll take some pictures of it rigged up if I go down that path. I'm OK with using some filler to smooth it out afterwards.

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Re: Advice to pull the dents out of jacking point

#15 Post by Dave Whittick » Mon Oct 07, 2019 8:50 am

Phil Planck wrote:
Sat Oct 05, 2019 10:02 am
Dave
Can you show on above pic where you put the stud/s?
That can be repaired, but you have to start at the edges of the dent and work your way to the deepest part. The age old advice is last in, first out. This will be a slow process and require quite a few studs. There are some clever tools out there for leveraging studs instead of using a slide hammer. They give you more precise control.
Image

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