Rust above gutter line on side of roof ?

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Re: Rust above gutter line on side of roof ?

Post by jaylee » Tue Sep 20, 2016 10:16 pm

Bongolia wrote:Not an uncommon repair in restoration stuff. Thames 15cwt and early Sherpa's, yes people restore Sherpa's!
It is fairly common.
It always comes down to economics in the end.

To carry out a "proper" repair to a complicated area such as this is would require the local roof skin panel to be removed to expose the structure beneath . That area may require additional welding and treatment then the "cover* replaced.
I would estimate for a repair such as this from the images using metal as;

Remove all necessary trims etc and refit 5 hrs
Cut out affected panels and dress 2 hrs (E)
Fabricate inner support panel work 3 hrs (estimated cos we dont know till the caps off)(E)
fabricate cover panel 3 hrs
weld into position 1.50 hrs
load and level area 2 hrs
prepare for paint 2 hrs
refinish in color to match blending adjacent panels 3hrs
re seal all affected areas 1 hr
labour @63 pph
plus materials paint and sundries at MLP (150.00-200.00)
+ VAT at 20%
That would include identifying the initial cause and trying to correct it.
That should give a "proper" repair that would probably out live the rest of the van but would only ever include a 1 tyear warranty!
This is an estimate and would be subject to stripping.
That is a proper job.

Its all horses for courses and emotion should not be a factor Benji Bongo is really just a Bongo at the end of the day.
:( :(
And no I would not want to do it it, it would interfere with my Bongoing time away. :P


re
Funny enough. The Bedford CF1 was also prone to this sort of corrosion on the "pie crust"..

My Old CF (owned in the late 1980's.) in particular started to look like a half opened tin of tuna..
Cheaper by comparison to a race horse...
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Re: Rust above gutter line on side of roof ?

Post by mikeonb4c » Wed Sep 21, 2016 6:31 am

g8dhe wrote:Spoke with Gerry today, and yes that is the plan, two or three panels replacing the outer skin, from an old donor vehicle. He has a plasma cutter so shouldn't be to bad a job to cut them out and whilst off will waxoil the inside cavity. The rust appears to be away from the internal supports so hopefully it hasn't spread to them.
Interesting. Can all that be done without affecting internal lining etc or will that have to come out? Also, risk of fire plus waxoyl melting and running anway as well as vaporising and impregnating lining materials, if hot technique such as welding used. Have all these been considered. I'd consider casting a new fibreglass piece against the original before cutting out, brush (not spray) waxoyling inside and then affixing new fibreglass. That is, if the skills are there to do it. :roll:
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Re: Rust above gutter line on side of roof ?

Post by Bongolia » Wed Sep 21, 2016 2:33 pm

mikeonb4c wrote:
g8dhe wrote:Spoke with Gerry today, and yes that is the plan, two or three panels replacing the outer skin, from an old donor vehicle. He has a plasma cutter so shouldn't be to bad a job to cut them out and whilst off will waxoil the inside cavity. The rust appears to be away from the internal supports so hopefully it hasn't spread to them.
Interesting. Can all that be done without affecting internal lining etc or will that have to come out? Also, risk of fire plus waxoyl melting and running anway as well as vaporising and impregnating lining materials, if hot technique such as welding used. Have all these been considered. I'd consider casting a new fibreglass piece against the original before cutting out, brush (not spray) waxoyling inside and then affixing new fibreglass. That is, if the skills are there to do it. :roll:


My latest aquisition has the same problem as the OP but not as extensive, I hope [-o<

I will be stripping out all the interior trims to carry out other repairs, treat and insulate the van and hopefully find the cause.
If viable I will use a cold repair to that area and take pics as I go.
Just need to find out how to post the pics. :?
Probably in the New Year tho.
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Re: Rust above gutter line on side of roof ?

Post by g8dhe » Thu Oct 20, 2016 7:28 pm

Well work is well underway!
The roof doesn't have any structural function and the inner skin protects a lot of the cables etc.
The outer skin material is a lot thinner than you might expect as well! MIG welding is blowing holes even in the good metal so they are having to use TIG welding which is easier to do on thin material.
Progress so far is documented here http://www.g8dhe.net/bongo_images/tin_worm/
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Re: Rust above gutter line on side of roof ?

Post by mikeonb4c » Thu Oct 20, 2016 8:39 pm

Serious looking stuff Geoff and v interesting to follow. So great to see Bongos being cherished in this way - they're worth it :D
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Re: Rust above gutter line on side of roof ?

Post by Bongolia » Thu Oct 20, 2016 9:19 pm

g8dhe wrote:Well work is well underway!
The roof doesn't have any structural function and the inner skin protects a lot of the cables etc.
The outer skin material is a lot thinner than you might expect as well! MIG welding is blowing holes even in the good metal so they are having to use TIG welding which is easier to do on thin material.
Progress so far is documented here http://www.g8dhe.net/bongo_images/tin_worm/
Great stuff!
Very interested to see the images as I have almost exactly the same problem!
Rusted in almost the same places too. They seem to be where the roof inner sub assy, screen pillar and D pillar joints are.
I am wondering if the off side flexes more because of the sliding door as the other side on mine at least is perfect!
Yes, the outer skin is 22/24 swg and difficult to get a weld to, butting it with a MIG is nigh impossible without blowing holes. :(
Capping it would seem the way for me to go.
I need a local Bongo breaker. [-o<
Looking forward to the next set of images.
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Re: Rust above gutter line on side of roof ?

Post by g8dhe » Sat Nov 19, 2016 3:08 pm

Right job completed by Fred & Jerry @ Discount trucks final results and the other pictures here, click for the details;
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The roof line rust appears to have started at the spot welds in the gutter, not all of them by any means, but close to joins/gaps in the mastic that is also used when they are built so possibly leaks - but that doesn't account for the corrosion at the nearside upper rear corner where its a single section of curved sheet!
Last edited by g8dhe on Sat Nov 19, 2016 3:19 pm, edited 2 times in total.
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Re: Rust above gutter line on side of roof ?

Post by haydn callow » Sat Nov 19, 2016 3:16 pm

That's impressive....should give you a few more years......happy days!!
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Re: Rust above gutter line on side of roof ?

Post by helen&tony » Sun Nov 20, 2016 4:44 am

Hi
Nice job...and yes, it should last a bit longer now!
Cheers
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Re: Rust above gutter line on side of roof ?

Post by cmm303 » Mon Nov 21, 2016 6:53 am

Got to get back in touch with these guys myself. When I last spoke to them they were vey busy with an unexpectedly challenging job on a roof!! Pleased to see it has turned out well, Geoff.

I found it quite honourable that Discount Trucks were very guarded about discussing more work than the bongo is worth. Emotionally challenging! Big jobs like this and Bongolias must be right on the balance of ageing tin vs strong bongo prices.
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Re: Rust above gutter line on side of roof ?

Post by Ian » Mon Nov 21, 2016 8:40 am

Nice one! I will add Discount Trucks to the Rust Directory.
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Re: Rust above gutter line on side of roof ?

Post by Bongolia » Tue Nov 22, 2016 11:19 am

cmm303 wrote:Got to get back in touch with these guys myself. When I last spoke to them they were vey busy with an unexpectedly challenging job on a roof!! Pleased to see it has turned out well, Geoff.

I found it quite honourable that Discount Trucks were very guarded about discussing more work than the bongo is worth. Emotionally challenging! Big jobs like this and Bongolias must be right on the balance of ageing tin vs strong bongo prices.
That`s very true. In the Wasps case it would not be economically viable. If this had been a customers then the advice would have been to look for a better example to start from.
However I am quite enjoying the dissection and the more I get into it the more I enjoy it!
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Re: Rust above gutter line on side of roof ?

Post by BongoBongo123 » Tue Nov 22, 2016 3:52 pm

Nice feeling to know it is as it should be again. :)
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Re: Rust above gutter line on side of roof ?

Post by Jillygumbo » Tue Nov 22, 2016 6:25 pm

Good job! Are you going to put the Fiamma back on Geoff?
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Re: Rust above gutter line on side of roof ?

Post by g8dhe » Tue Nov 22, 2016 10:33 pm

Oh yes, none of the corrosion started near the mounting points. Best guess is gaps in the mastic allowed condensation in, waxoil should have cured that problem!
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