Jacking point GRP hole repair

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LotusMonkey
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Jacking point GRP hole repair

Post by LotusMonkey »

Looks like at some point in my Excel SE's history a front jacking point has been used with the plate missing!

The jacking point has a deep crevice (4cm at one point) that I need to repair. I know I will need to check for other cracks etc, but I plan to have a go at this myself and wondered if anyone has any advice on GRP repair kits? I am currently looking kits from boat places such as WessexResins.co.uk - but that is only very top line research at this point.

Lucky bodyshop that gets the full respray that is needed once the car is no longer SORN'd can have the pleasure of making it look pretty, for now its about stopping any further damage.

Any thoughts welcome - don't worry about jacking point advice - I don't use those spots :)

Duncs
"A specialist job is just one I have not learnt to do yet...." :D

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Pete Boole
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Re: Jacking point GRP hole repair

Post by Pete Boole »

Post up a couple of photos so we can see more clearly where the damage is. Obviously none of the fibreglass is 4cm thick - the jacking point is below foam-filled voids.

Pete

LotusMonkey
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Re: Jacking point GRP hole repair

Post by LotusMonkey »

I won’t have any pics until back up with the car. It’s definitely through to the crumbly foam core and reasonably deep. Will get some pics next time up.
"A specialist job is just one I have not learnt to do yet...." :D

LotusMonkey
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Re: Jacking point GRP hole repair

Post by LotusMonkey »

Has anyone got any recommendations for a low-density (open cell?) polyurethane filler to use on the void damage, before I move on to the GRP stage? Other than builder's expanding foam! (I jest!)

I've ordered replacement jacking plates for each of those missing, not that I plan to use them!

Duncs
"A specialist job is just one I have not learnt to do yet...." :D

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Pete Boole
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Re: Jacking point GRP hole repair

Post by Pete Boole »

Your suggestion to use builder's expanding foam is actually a good one - it has the great advantage of being able to be directed where you want it. All the other foaming products I have seen are liquids. Since it is the shape of the foam filled void and not the foam itself that creates the strength I would indeed use builder's foam. The only thing you need to check is whether it is dissolved by styrene (in fibreglass) - if it is you can use an epoxy resin for your repair.

Pete

LotusMonkey
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Re: Jacking point GRP hole repair

Post by LotusMonkey »

Every day is a school day! Thanks Pete.
"A specialist job is just one I have not learnt to do yet...." :D

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Pete Boole
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Re: Jacking point GRP hole repair

Post by Pete Boole »

Thinking more about it Dunc - if the crack is that severe you might want to repair it from both sides. That would give you the opportunity to remove the existing wedge of foam, make a great crack repair, and then use the foaming product of your choice (polyester/epoxy) to reinstate the foam wedge using, say, plywood as the baffle. This would give you the strongest repair.

Pete

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Alan_M
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Re: Jacking point GRP hole repair

Post by Alan_M »

If the area of foam you are talking about is at the front of the front footwells that makes the sloped shape - this piece is not structural, the layer of fibreglass on the inside of the car is very thin - can be snapped very easily by hand. I suspect when made they made the foam wedge in a mould, placed it into the footwell and then fibre glasses in with just one or two layers.

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