paint blistering on roof posts

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Velocette
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paint blistering on roof posts

Post by Velocette » Wed Nov 24, 2010 11:35 pm

My 95 Bongo is almost immaculate paintwise but there are clusters of paint blisters on the two front and the nearside rear roof posts a few inches below (tin) roof level. I intend to get these repaired before the winter really sets in.

Is this a common site for rust on an AFT Bongo?

Are there hidden seams at these locations?

the arches and underside are good.


Should I be worried?
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Re: paint blistering on roof posts

Post by lpgimports » Thu Nov 25, 2010 10:46 am

ouch hope its ok but can be sign of it rusting from the inside at the top of the pillars due to condensation build up in that area.

Paul
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Re: paint blistering on roof posts

Post by Velocette » Thu Nov 25, 2010 7:12 pm

lpgimports wrote:ouch hope its ok but can be sign of it rusting from the inside at the top of the pillars due to condensation build up in that area.

Paul
Thanks for the reply

Eek! That did cross my mind. If it is that is it hard to fix or at least contain?

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Re: paint blistering on roof posts

Post by lpgimports » Thu Nov 25, 2010 11:23 pm

Anything is fixable, problem is there is no access behind so to do it properly is hard work very visible and therefore expensive sadly...
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Re: paint blistering on roof posts

Post by Velocette » Fri Nov 26, 2010 11:34 am

lpgimports wrote:Anything is fixable, problem is there is no access behind so to do it properly is hard work very visible and therefore expensive sadly...
Quite near the windscreen as well. Oh woe :(

I suppose the sooner I get it sorted, the better.
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Re: paint blistering on roof posts

Post by lpgimports » Fri Nov 26, 2010 12:24 pm

post a close up photo, can also suffer from sun scorching which can make the top coat flake in this area much easier to deal with.

Paul
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Re: paint blistering on roof posts

Post by Velocette » Fri Nov 26, 2010 2:52 pm

lpgimports wrote:post a close up photo, can also suffer from sun scorching which can make the top coat flake in this area much easier to deal with.

Paul
OK I will get some pics tomorrow hopefully. Being black I expect it is more vulnerable too. Fingers crossed...
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Re: paint blistering on roof posts

Post by Velocette » Wed Dec 01, 2010 1:25 am

Velocette wrote:
lpgimports wrote:post a close up photo, can also suffer from sun scorching which can make the top coat flake in this area much easier to deal with.

Paul
OK I will get some pics tomorrow hopefully. Being black I expect it is more vulnerable too. Fingers crossed...

Paul, please bear with me. I have taken the pics I will transfer them from the camera whn I get a minute, have been having a hectic time.

It is only two pillars affected and also, I noticed very small pimples on the chamfer below the side windows, also near side. A glimmer of hope as maybe that was how the sun caught it on someones drive etc.
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Re: paint blistering on roof posts

Post by Northern Bongolow » Wed Dec 01, 2010 3:42 am

my black tin top has suffered on the flat areas of the roof,mine looks like heat damage,ive also been told that the black ones tend to have very thin paint.
when i was working on a door snotty recently i gently flatted and rubbed through to the primer,so this maybe backs up this theory #-o.
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Re: paint blistering on roof posts

Post by Velocette » Thu Sep 08, 2011 2:53 pm

Well the pictures I took where crap but the update is that although the blisters have got no worse a wiggly horizontal crack apeared early in the year above them and the immediate area of the panel is springy. I have checked with a magnet and there is no gaping hole there. Also the blisters seem to be rock hard, not like rust blisters.

I am reluctant to start exposing it now just two weeks away from my holiday.

My question is: Is there a hidden seam there, and if so, could the factory filler have failed, possibly due to sun damage?
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Re: paint blistering on roof posts

Post by Velocette » Thu Sep 08, 2011 4:25 pm

I have just been looking at the body panel drawing and the crack is just where the edge of the roof panel ends. this is good in a way because I think the front A post panel goes up inside the roof so fingers crossed the spot welds have not failed, just the filler. The strength is mostly in the inner section of the post I would guess. Half tempted to dig it out but too scared of what I might find. :shock:
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Re: paint blistering on roof posts

Post by missfixit70 » Thu Sep 08, 2011 5:34 pm

Don't be such a chicken :wink: may be best to wait til after the hols though, just in case :wink:
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Re: paint blistering on roof posts

Post by mikeonb4c » Thu Sep 08, 2011 5:54 pm

missfixit70 wrote:Don't be such a chicken :wink: may be best to wait til after the hols though, just in case :wink:
Yup. I decided not to chicken out over grinding off the paint and rust on wheel arches to see what was underneath. Best in the long run. One benefit of a rust-through hole (says he putting a +ve spin on it) is that you can use it to squirt anti-rust into the interior.

I have a few isolated spots on the metal below the AFT and above the windscreen. V. slow developing (may be stone chip results) So far I''ve just scratched off surface rust, Kurusted, zinc primer (can sprayed into lid then applied with touch up brush), metallic, then single part lacquer (can lid/brush again).

I can't get out of my head the feeling (right or wrong) that the ageing lacquer is getting more brittle and porous to moisture, and that the car would benefit from a complete recoating with lacquer. :roll:
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Re: paint blistering on roof posts

Post by kloonsy » Thu Sep 08, 2011 7:50 pm

Velocette wrote:I have just been looking at the body panel drawing and the crack is just where the edge of the roof panel ends. this is good in a way because I think the front A post panel goes up inside the roof so fingers crossed the spot welds have not failed, just the filler. The strength is mostly in the inner section of the post I would guess. Half tempted to dig it out but too scared of what I might find. :shock:
Not sure what you mean by filler, but polyester body filler as not used in the manufacture of vehicles. Most likely a run of braze weld between pillar and roof, lead at a push dependant on age of vehicle.
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Re: paint blistering on roof posts

Post by Doone » Thu Sep 08, 2011 9:35 pm

Kloonsy, this is your speciality area... we had ours repaired and 'leaded' locally 3 years ago, and its just beginning to bubble again. It will need to be repaired again, is there anything else you can suggest that would help?
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