Black Fibreglass Glue

[Shed TVR]

Hi all,

I'm trying to find what the hard black adhesive that's used to bond sections of fibreglass together on the body is, it's the same stuff as below:



I've tried sikaflex 221 but it does not set as hard as this, is it sikaflex 227 or something else?

Thanks

[fieryfred]

That looks like the bonnet hinge casing.
I ran a full length bar through mine. Theres a few posts on the same topic.
I did use sikaflex ??? (i will try & find it. Tidy Betty has been in ) & west system six10 using a normal cartridge gun.
The single bolt pivot is very poor & loads fail.

[poppopbangbang]

DP490 - https://www.3m.co.uk/3M/en_GB/company-uk/3m-produc...

[Dougal9887]

Surely you would use 2 part polyester bonding paste which is specifically made to bond sections of moulded GRP.

[phillpot]

https://www.fibreglassdirect.co.uk/1kg-freefix-bon...

[ATG]

Dougal9887 said:

Surely you would use 2 part polyester bonding paste which is specifically made to bond sections of moulded GRP.

For permanent bonds and repairs, yes. The only silkaflex I found round the Chim was for stuff you'd want to be able to remove occasionally, such as the access hatch through the wheel arch to the back of the headlight unit.

If it has been used to bodge a repair to the bonnet hinge, I'd remove all of it and repair it with fibre glass matting and resin. It's pretty easy. In fact it's the first fibre glass repair I ever attempted and it's held up ever since. Worth having a play with fibre glass. You can repair and make all kinds of stuff with it. None of it is likely to be beautiful, but it can be remarkably strong and durable.

[Shed TVR]

fieryfred said:

That looks like the bonnet hinge casing.
I ran a full length bar through mine. Theres a few posts on the same topic.
I did use sikaflex ??? (i will try & find it. Tidy Betty has been in ) & west system six10 using a normal cartridge gun.
The single bolt pivot is very poor & loads fail.

Excellent idea, unfortunately I already had a go at repairing this with fibreglass matting and resin so I'll have a think about if I should remove this and put a bar through instead. The bar would definitely work better.

poppopbangbang said:

DP490 - https://www.3m.co.uk/3M/en_GB/company-uk/3m-produc...

Thanks that looks like good stuff.

phillpot said:

https://www.fibreglassdirect.co.uk/1kg-freefix-bon...

Thanks Phil I already have a bit of this stuff, good to know it could work for this.

ATG said:

For permanent bonds and repairs, yes. The only silkaflex I found round the Chim was for stuff you'd want to be able to remove occasionally, such as the access hatch through the wheel arch to the back of the headlight unit.

If it has been used to bodge a repair to the bonnet hinge, I'd remove all of it and repair it with fibre glass matting and resin. It's pretty easy. In fact it's the first fibre glass repair I ever attempted and it's held up ever since. Worth having a play with fibre glass. You can repair and make all kinds of stuff with it. None of it is likely to be beautiful, but it can be remarkably strong and durable.

I already have a fibreglass repair kit, I will probably go ahead and use this for the repair thanks.

Dougal9887 said:

Surely you would use 2 part polyester bonding paste which is specifically made to bond sections of moulded GRP.

I was trying to copy how it was originally done, I can certainly use a 2 part epoxy or something if that will work better. Looking at the pictures at the end of this post - has someone other than TVR been in here and bodged this? The entire of this fibreglass piece was attached to the bonnet with the black adhesive:




Thanks for the help, much appreciated.

[Dougal9887]

I've never been that far into the bonnet to be sure, but I suspect that it's original TVR. The bonding paste you show looks very like the bonding paste between the inner and outer front valance lips which I did have to repair.
I would sand that all off using a sanding wheel on a grinder, for a fresh start. Clean both surfaces with acetone, using very sparingly. Then re-bond using the correct polyester bonding paste. This contains styrene which 'eats' slightly into to GRP layup, providing a sound bound. I don't believe you will achieve as good a bond using epoxy (or anything else) on GRP.
Dougal

[Shed TVR]

Dougal9887 said:

I've never been that far into the bonnet to be sure, but I suspect that it's original TVR. The bonding paste you show looks very like the bonding paste between the inner and outer front valance lips which I did have to repair.
I would sand that all off using a sanding wheel on a grinder, for a fresh start. Clean both surfaces with acetone, using very sparingly. Then re-bond using the correct polyester bonding paste. This contains styrene which 'eats' slightly into to GRP layup, providing a sound bound. I don't believe you will achieve as good a bond using epoxy (or anything else) on GRP.
Dougal

Thanks very much Dougal, this sounds like the best method and I've ordered some acetone and polyester bonding paste.