Trailer query

[Gavinm]

Not sure where to place this query so I went for the technical section.

I have an enclosed trailer with a translucent grp roof that I need to extend by 300 mm (I know).
Is it possible to join an additional section to the existing single sheet (remove ally end panel and corners, extend sides and refit corners and end).

It is mastic sealed and clamped in pre formed ally sections like a lorry. I imagine the mastic is effective and am worried about stripping any more than I need to without causing significant damage.

Any thoughts and ideas greatly appreciated.

Thanks
Gavin

[AndyMil]

if it's same as we fit to trucks, it should be a section, the grp sheet stuck to the section with mastic and a capping on top, held together with rivets.
Drill the rivets out, remove the capping, use a wide scraper to ease the roof sheet away from the mastic, do what you need and reassemble, try to get "sealed" rivets(designed for this kind of application)
As for the sides, you can buy proper panel joint section. like an extended T with a lip at the bottom.
We use a lot of gear from http://www.servicemetals.co.uk/transport.htm these guys are most helpful. where are you based?

Have a look at threads from Wilksy and Adam, they've both converted flats to boxes.

[Gavinm]

Hi Andy
Thanks for your help.
I have 3" sections with a grp roof panel sealed and riveted in with top caps as you describe. Not sure how much a new one piece roof is but I think it might be better to replace the lot in one go.
The roof has light wieght curved supports underneath that have been glassed to the main roof. Are these fitted after the roof skin is fitted? (ie fit the grp, turn it over and bond the brackets to it)?
I dont know the cost of the roof side bars but it might be better to replace them with the correct length and reuse the corners and ends.
I'll check out service metals.
I was tracking Adam's build - very professional.
Thanks again
Gavin

[Gavinm]

Meant to mention, I'm near Watford in Herts.

[AndyMil]

Hi Gavin, The bars you refer to are "roof sticks", Side pieces are Cant rails.
The roof would come complete, ie; front and side cant rails, corner castings, sheet and sticks, all assembled. pricing is surprisingly competitive.
side frame is built first, then the sticks are fastened to that, sheet, then capping, flip the lot and glass the sticks on.
there are a few manufacturers of extrusions, compare the sizes and drawings in the online catalogue, you may have to go back to the trailer manufacturer.
Andy

[Gavinm]

Hi Andy
Done the research and had a long chat with Service metals (really helpful) and i think I have got my head around it now.
I will take the existing roof off, extend the trailer, strip back the roof components and reuse the corners, sticks and ends and replace the rest (sounds so easy).
Do you know where a is a good place for rivets please?
Also, do I use mastic or double sided tape between the frame and the grp and what spec would be good?
Finally (for now) do I seal the trim sections that fit on the top?
Thanks again
Gavin

[AndyMil]

if there's no fasteners through the rail and panel, it's probably built with Sikaflex 252, which is an assembly adhesive.(might be a bitch to get off, razor scraper is the only way)
Any good fastener supplier should be able to sort you the sealed rivets, tell them what you want them for if they don't understand.
Use a none setting mastic for the rail to sheet join, Service Metals should be able to help you there, as Truck Roofs is one of their divisions.
Once everything is assembled, a thin bead of sealer around the trim and you're sorted!
No probs, glad to help anyone involved in our favourite pastime.

[guilleracing]

I recently removed the roof from my lorry to reduce the height by 6 inches to comply with local ferry restrictions.

When I re-attached the rood panel, I used an Evostick product.

This was called " Sticks like sh*t" If you google it you will see that it is a trade adhesive.

I also built a correspondingly lower luton top over the cab, in total I used 37 tubes of the stuff in the whole project. There are no rivets in the luton section, it doesn't leak and puts up with 90MPH on the motorway with no signs of distress.

The product can be applied to wet surfaces and is tolerant of some dirt etc.

I once stuck a fitting into a wet gutter as an emergency repair during a storm. Later in the year I went to remove it and found that I couldn't get it out without destroying the gutter!

If I were doing a trailer conversion for a client, I would use this product.

I hope this is useful to you.

Greg.

[redturner37]

I can confirm Gregs method of lowering the roof.....

[bantoracer]

Hello Gavin
I think I remember selling you this trailer. I bought it off the Coley Brothers. I also remember Andy telling me he had all the work done by a local engineering firm. He lives near you so might be a good contact to help with advice on materials used. Hope this helps and good luck. Ian.