Composite fiberglass/foam panel build question

[VerMonsterRV]

Hi, I am in the process of thinking through a camper build and at this point I think a cab over chassis truck (like a MB 917 or Fuso FG) would be a good base. I am then thinking a Total Composites shell. I really like what they are doing and seems like a great product. I also know that the aluminum corners are a great idea to ease the build and save time. Now the question, say I prefer the look of a molded shell with no aluminum corners. Has anyone taken panels like these and glassed them together? I know this would increase the build time and require painting but curious if anyone has done it and how were the results.

 

[part time nomad]

To round off the corners with glass fibre would require cutting away material where the two panels meet and could create a weakness in the corners, unless you could put the strength back in, by creating a joining method inside.

 

[TernOverland]

Hi, I am in the process of thinking through a camper build and at this point I think a cab over chassis truck (like a MB 917 or Fuso FG) would be a good base. I am then thinking a Total Composites shell. I really like what they are doing and seems like a great product. I also know that the aluminum corners are a great idea to ease the build and save time. Now the question, say I prefer the look of a molded shell with no aluminum corners. Has anyone taken panels like these and glassed them together? I know this would increase the build time and require painting but curious if anyone has done it and how were the results.

I would urge you to talk to Andreas at Total Composites. First, he offers fiberglass extrusions in addition to aluminum. The fiberglass eliminates cold bridging. Second, the extrusion construction is stronger. Third, the formulation used in the fiberglass skins that TC uses are not recommended to be used in a glassed application. I'm not sure why, but he can explain.

 

[VerMonsterRV]

Thanks for the info, I won't bother Andreas just yet, have a few more months to work out the details (and will probably take the easy proven route of the prefab corners). I am curious about the panels though. I have molded composite parts for our boat and RV using epoxy/divinycell (though much smaller than an RV). I was under the impression that any post cured glass work is all mechanical bond. This is just a guess, but the skins seem to be thin (max 2mm) and may not allow enough of bond area with the new glass? If I was to attempt this the plan was to chamfer/bevel (make a custom bracket for a grinder to hold it at the proper angle) both the inside and outside corners and lay the glass on using epoxy and a fiber tape (would have to look into the various options carbon/kevlar or just fiberglass).

 

[Victorian]

Hi Guys,

I thought it's time to jump into the conversation:
You can certainly "glass" onto our Fiberglass skin for repairs. The bonding strength will be plenty. What we don't recommend is structural work. The manufacturer of our FRP skins (Lamilux in Germany) made it very clear to us that you will not not get a structural sounds bond either with Polyester resin or Epoxy to the Skin. Although I can't remember the exact reason but I believe it had something to do with the chemical composition of the FRP Skin. Apart from the mess and time is take to "glass" the corners, I would recommend our Fiberglass extrusions that are thermal transfer free.

Cheers,

 

[ripperj]

I would guess it had to do with the strength that the extrusion supplies to the piece that’s at 90 degrees to any force applied.
Fiberglass and other fibers like carbon are very strong in tension, but the bond between the fiberglass panels and the foam is fairly weak compared.

If you make a 90 degree joint, and glass both the inside and outside corners, and then apply a force to try and separate the joint, most of the strength comes just from the outside glass mat, because again the inner foam/fiberglass panel joint is in tension and the foam can tear easily


Sent from my iPhone using Tapatalk Pro

 

[VerMonsterRV]

Ok, that makes perfect sense. Coming from a sailing background now I see why they stop the coring and move to solid glass for the corners. This seems like it could work here (well depending on the Total Composites panel makeup from what Victorian posted, but definitely possible with a epoxy/divinycell custom panel). Once the corner is formed you would have to insulate it but it could work. Way more work and unless you had some skill (and luck), potentially less quality than a TC panel/corner extrusion box.

 

[mog]

I had the same thoughts as you with the 'look' of the box corners. But after seeing the Total Composite corners in person, they are very 'attractive' and actual add a finished look to the shell, not detract from it.
On a side note, when we were assembling Quaide's cabin for Trucky McTruckface, a few of the guys (fellow helpers) and I were wondering if filling the hollow area of the extrusion would make them stronger.
Although I am sure they were tested in the laboratory by German engineers to specific standards, we took the rural American approach and beat on one with a big hammer.
I think the hammer would have given way prior to the extrusion (these were the FRP extrusions). No flex or movement. We had thought they would deflect, but nothing.
Come to think of it, I guess we should send Andreas at TC a bill for this testing. What do German engineers charge per test? :sombrero:

 

[Victorian]

Mark,

You are funny It sounds like you used the same tesing method I implemented last time I was at the factory. https://www.youtube.com/watch?v=mg63M6DaivE

 

[SantaCruzNomad]

Glassing inner radius

StyroMAX recommends glassing over the inner radius to strengthen it.

https://www.youtube.com/watch?v=qJPvvnCE8XU

 

[ScottReb]

This is exactly what UroCamper out of Spain has been doing for years. Uses Stador brand panels, routes the edges, and CF tape to join the edges. Victorian is giving the correct info on his panels, you should speak with the individual panel manufacturer and get their info.

 

[rruff]

StyroMAX recommends glassing over the inner radius to strengthen it.
https://www.youtube.com/watch?v=qJPvvnCE8XU

I think what is being discussed here is joining panels at the edges.

 

[ScottReb]

Just realized you are currently in Spain. I would contact UroCamper directly. So many options and experience in that part of the world.

 

[Joe917]

Our box is composite fiberglass/foam/ply,. The corners are glassed inside and out and protected with stainless corners. The truck (917 AF) has been traveling for 22 of the last 24 years with no failures. the box is a solid mount so the box takes huge stresses off road, no problem. So done right glassed corners can be very strong.

 

[VerMonsterRV]

Hi Scott, we are sort of in Spain. We are currently in the Canaries on the way across the Atlantic on our sailboat (or current offroad vehicle ;-) ). We leave in a couple of weeks for the crossing. Actually I had considered just getting a camper in Spain, traveling Europe then the rest of the world, then selling and doing something for North America. But we have been away for a while and it is time to be home for a bit.