Gp4 rear Arches

[Mark Cowling]

Hi all when fitting square Gp4 4 rear arches has anyone fitted the arch lip behind the body panel to make filling easier ? or have people fitted the lip on the outside by slimming the two halves? Regards Mark.

[guy mayers]

Hi Mark, the conventional way of doing it is to remove the existing arch from the rear panel and then thin the bodywork by removing the gelcoat. The new arch is then thinned by removing some of the matting from the back until both can be put together without too much of a lip. Both panels mating surfaces should be cleaned and softened with acetone (nail polish remover) before being bonded together and riveted until cured. Once cured any excess material can be removed from the original rear panel up to the new arch and additional layers of mat/resin laid over the joint.
However, I would recommnd that the tub extensions are fitted first in the same way. This is because there are more datum lines to make sure it goes on right, these are the swage line plus the trailing edge of the tub. Once fitted this will give you the correct position for the rear arch to make sure that the curve follows through into the tub.
Guy

[Mark Cowling]

Hi Guy thanks for that, the bonding inbetween the two layers, would one layer of mat and plenty of resin pulled up with the rivets be OK? regards Mark.

[guy mayers]

It's worked ok on mine except for one area where something flew across the boot and has caused a very small crack in the filler ovet the joint. Job is now at least 9 years old so yes!

[Mark Cowling]

Thanks again Guy Regards Mark.

[Mark Cowling]

Hi all ,After bonding on the arch with resin & matting is there a special body filler for fiberglass or does a good quality filler that does not shrink do the job ? Regards Mark.

[guy mayers]

Hi Mark, try ringing Geoff Turton (0151 420 3420) for this one - the expert is in the next unit to him and I'm sure Geoof would love to hear about your plans!!
Cheers
Guy