Patching/repairing poor man’s fibreglass

[Eskapet111]

Hello Everyone

I purchased a DIY Foamie camper that is built with a small timber frame and foam in between on the outside and ply in the inside . The foam has been covered with canvas and pmf.
I didn’t do any of this ,this just what the guy I bought it off told me .

There is a few sections it looks like he has messed up the canvas and just siliconed over and there is one section that the silicon has come off now and I can see bare wood and foam .
I’m currently travelling with this camper and going to be on the road for 5 months with it so I’m just looking to do what is necessary to make it water tight and make it look a little nicer when I sell it . Don’t have the time or facilities to do anything major .

Does anyone have experience with patching pmf ?
The part in my trailer that is the worse and most urgent to fix is indented in so I will need to build it up to be level with the rest of the surface .
I was thinking of maybe using some sort of fibreglass filler but not sure if that will work ?
Thanks!!

[rjgimp]

Welcome to the forum!

PMF is very durable and easy to repair, even in the field. Basically you can cut away any parts you wish to replace with a sharp utility knife, then slather on some Titebond 2 wood glue and apply an appropriately shaped piece of canvas. Use a wide putty knife to smooth out the canvas and work the glue into the weave of the fabric, then let it dry completely. Apply a coat or three of exterior latex house paint and you're good to go.

There happens to be another current thread on this same topic and a few guys have chimed in who are very experienced with PMF. I know any of them would be happy to answer your specific questions. They might have some thoughts on filling low areas. I don't have any experience with that.
viewtopic.php?f=65&t=76226

[Eskapet111]

Hi Rob
Thanks so much for your quick reply !
I will post in the thread you linked and hopefully some of the others will chime in too.
I have some questions regarding what you suggested with patching it ;

- if I do this patch I’m assuming it’s going to be pretty noticeable as a patch as you’ll see the lines , is there a way to do it without it being as noticeable but still waterproof?
- if I patch it I believe I need to overlap the the patch over the cut out area , is that correct ?
- with the canvas , the only stuff I can find is 100percent cotton drop sheets … is this going to be suitable or if not do you have any suggestions on what and where to get the right canvas ?
- is just straight top coat paint (no primer ) okay ?


And if anyone else can chime in about the hole being slightly indented and the best way to build it out flush with the rest of the surface that would be much appreciated.


Also , if anyone has any experience with using filler could you let me know as this would be easier for this hole that’s bare wood as it’s up against the curved window frame, so if I use canvas will have to cut it around the curved frame and try tuck it into the frame which may be difficult… but I think I’ll go with canvas for the other patches .

Thanks again !

[rjgimp]

- if I do this patch I’m assuming it’s going to be pretty noticeable as a patch as you’ll see the lines , is there a way to do it without it being as noticeable but still waterproof?

Yes, it will be noticeable, all seams in other types of skins/siding are noticeable too. Think about vinyl or steel siding on your house. Where one horizontal piece of siding ends and you install the next one you overlap the ends just a bit. Usually the piece towards the front of the house overlaps the piece towards the back of the house so that when you look at the house from the street the seams all blend in. If you look at it from the back or side yard you will see every single overlap very clearly. I think our eyes have been trained somewhat over the years to notice those less.

- if I patch it I believe I need to overlap the the patch over the cut out area , is that correct ?

Yes.That's the main focus of what they are discussing in that other thread.

- with the canvas , the only stuff I can find is 100percent cotton drop sheets … is this going to be suitable or if not do you have any suggestions on what and where to get the right canvas ?

Yes, cotton drop cloths from Walmart, Home Depot, Harbor Freight and the like are what most people use.

- is just straight top coat paint (no primer ) okay ?

Yes, exterior latex. Get some of the mistinted stuff from the paint department at the local big box home center. It will usually be marked WAY down. Apply a coat over the whole trailer when you're done.