Glass fibre advice sought

[RogerS]

I've built this storage box out of MDF to protect the inside of the car

but it does weigh a fair bit. I was thinking about using the box as a mould and making a fibreglass box. It's been a long time since I did any fibreglassing. Are the steps as follows...

apply release agent to the box (maybe wax as I used pocket hole screws to make the box and I don't want the risk of glassfibre going down in the holes as it will make taking the fibreglass box out rather difficult)

apply a gel coat to the box.

start laminating sheets of fibreglass. How many? What guage? Should I put a sheet of chipboard or similar into the base as additional strength/protection?

How do I stiffen the sides and prevent them flopping down?

Finish off with more gel coat?

Anything I've forgotten? Is there a good cheap source of material anywhere?

many thanks in advance

 

[jasonB]

I would fill all holes and also put a small fillet in the internal corners.

Then give the "mould" a couple of coats of varnish or paint with a light rub down between coats, this needs to be done so the release agent does not just soak into the board.

You don't really need a gel coat for the surface against the mould as you are not really after a super smooth finish.

The bottom can be reinforced with ply (lighter than chipboard) placed between layers of mat. I would think somewhere in the region of 4 layers of 450g chopped strand mat then a surface tissue if you want the inside smooth.

Finish off with a flow/topcoat which contains wax that will flow to the surface and seal it from air.

The sides can be stiffened by bonding in ribs of PU foam at the edges/corners.

I had 70kg of resin from these people recently, there is info on the site about laying up etc.

Jason

 

[JFC]

The only fibre glassing i have done is upside down under a boat and i never had a problem with it dropping off . I was using the strand stuff , you would probably want the webbed stuff for your box . You could put 2x1 batterns in the box to give the fibreglass some sort of structure and then strike the box after it has gone off .

 

[aisuru]

forgive me if this is a bit of a faux pas on a woodworking type forum... but to be honest i'd say would it not be a better idea to just get a big tarpaulin or two and stick them in the back of the car to protect it. :?

just seems like a lot of trouble to go to, to build a fibreglass tub, when a tarpaulin or a bit of old carpet would likely do the job quite well.

just my £0.02

 

[jasonB]

If you could see the back of my freelander you would go for a load liner :wink:

JAson

 

[RogerS]

If you could see the back of my freelander you would go for a load liner :wink:

JAson

Absolutely! I've been chucking loads of old timber and such into the back. If I did'nt have the box then it would all have been punching through the back of the front seats!

Thanks, both Jasons....I've got all the information that I need, thanks.

 

[aisuru]

fair enough.

i'd hereby like to change my argument to 'why not get a van?' instead :lol:

 

[RogerS]

ahah...thought of that but then I'd get clobbered everytime I took stuff to the tip! With the box I can even put in asbestos sheets and take them to my local tip free of charge and without the hassle of permits etc.

 

[brianhabby]

Hi Roger

I've recently bought from these people.

Excellent service, prices and helpful advice.

regards

Brian