I have an older Merhow trailer (early 90s?). It's a 2-horse straight load gooseneck Turfman. The issue is the walls in the horse part - they are in layers as follows:
-outside & inside skin: FRP (some kind of moulded plastic/fibreglass) -sandwiched between is plywood
The frame is steel, I believe.
The problem is that I don't think this set-up is actually strong enough to prevent a horse going right through it. The plywood has rotted, and I had it replaced about 18 months ago (by going up from the bottom, the repair person said the rotten stuff just fell right out, he scraped it around, and then shoved a new piece of plywood between the two layers of FRP). However on a recent trip, one horse either scrambled or kicked and put a hole through the inside skin and a bunch of rotted plywood (that I thought had been removed, replaced, and resealed). It caused a bulge in the exterior skin.
Right now looking at doing one of the following:
-adding angle-iron along the floor and a sheet of steel 4' high the length of the horse stall
-doing the same as above with puck board or plywood or heavy rubber mats or used rubber belting
My coach wants to do the metal sheet, as doesn't think the rubber will help at all, since it will not do anything for structural strength. I think so too, but the welder we asked to look at it thinks rubber or puck board would be better and plywood would be OK.
Posted 2013-08-26 4:19 PM (#154297 - in reply to #154295) Subject: RE: FRP Horse trailer walls - strengthening
Expert
Posts: 5870 Location: western PA
The structural integrity of your trailer has been irrevocably damaged. The original wall panels were made with a plywood core bonded on each side to fiberglass FRP construction. Water leaks have rotted the core material and debonded the skins. The walls now have no strength and can be easily damaged by any striking of their surfaces.
The proper repair is very labour intensive, and if not effected by a DIYer, very expensive to hire. Basically the best skin inside or out is selected and left intact. The other skin is cut off preferably in a large sheet and removed intact from the core. A new core is bonded to the remaining skin, the cut off pieces are then bonded to the new core and strengthened. The cut seams are covered and faired and if outside, the panels are resprayed.
It may be easier to build new walls within the old. The inside skin should be removed, the rotted wood removed and the walls' structure examined. You may need new metal studs, stringers or other structural members. Once strengthened, the walls' inside surface can then be replaced with a variety of new materials.
You must ask yourself if a renovation of this magnitude is economically viable, considering a restoration like this could easily cost a couple of thousand dollars to have it accomplished. If you are handy with fiberglass and wood materials, the cost could be a quarter of the "professional" expenses.
Posted 2013-08-26 4:34 PM (#154300 - in reply to #154295) Subject: RE: FRP Horse trailer walls - strengthening
New User
Posts: 2
Location: BC
Thanks for the replies, unfortunately that is what I was afraid of. I had thought this issue had been dealt with 18 months ago... and of course I have 3 trips organized which I'm not interested in doing unsafely!
FRP Horse trailer walls - strengthening
