My Second Belly Band Thread

[David Tilston]

No.

Other then covering the ugly seam between the top and bottom half of the trailer. The belly band is just a system that lines up the two half's . Once the interior bandage hardens, that is where all the strength is. Once my filler hardens, that strength is doubled, or more.

[hrose414]

That makes total sense, so your filling the void where the inside band was. I'm sure I'll have more questions once I get going. Thanks

[David Tilston]

There is no inside band. On the inside are those pesky metal plates. They pull the inside out. The belly band pushes the outside in, till the top and the bottom line up. Then they run, what I call, a fibreglass bandage over the plates, from the inside. The top and bottom half never actually meet. It is that gap that I am filling. In a way that is somewhat structural.

This is what it looks like on the inside, under the elephant skin, (Ensolite).

[hrose414]

Sorry just want to be clear before I start hacking the trailer apart.

I think I got ya! So once the belly band is removed and the rivets cut back you fill it? You don't remove the plate on the inside. Is that right?

Thanks again for your help.

[Francesca Knowles]

Originally Posted by David Tilston

So, to try to explain what the wood was in the first place. When installed, it was about 2" wide, and fit into the protrusion in the fibreglass that the belly band sits on. It looks like it was glued to the inside fibreglass that makes up the dinette, and the lower shell. When the top of the trailer was put on, and the belly band was installed it was glued to the top as well, then screwed through the belly band into the wood. But the glue did not stick so good to the top half of the shell. It was separated when I opened it up. To detach it from the top shelf, I just ran a boxing knife blade between the shell and he plywood. It came apart. Digging out the glue, and remaining plywood, from the inside of the dinette fiberglass, was way more difficult.

This is most interesting, David. If you know, is there a similar arrangement up front?

I had wondered how the two shell halves stayed "in place" with the necessary gap until the bellyband plates/rivets/fiberglass strips were applied, and this might answer that question in my mind.

Thanks!

[David Tilston]

You might want to read the whole thread. I do indeed remove the plates.I cut them in half with a Dremmel tool, then I pull them out like rotten teeth. The process is better documented in this thread:
http://www.fiberglassrv.com/forums/f...ead-58763.html

In this thread, I went one step further then the first time. I used the same Dremmel, but with a sanding drum to sand off the rust I could get at, in the socket that the metal plate was in. This gave the new fibreglass a better bond, and made the whole thing stronger, I think. I also tried to stuff a piece of fibreglass, cut to a slightly smaller size then the original plate, then saturated with resin into the spot that the plate was. This was somewhat like pushing rope. I kinda gave up on that. Next time I will push it into the slot that the plate was in, before I saturate the fibreglass rectangle. Then I will try to get as much resin as possible in there after. Maybe I will use a syringe.

I don't think it would be a big deal if you did not remove them. I just wanted the rusty things out. More fibreglass that way.

Originally Posted by hrose414

Sorry just want to be clear before I start hacking the trailer apart.

I think I got ya! So once the belly band is removed and the rivets cut back you fill it? You don't remove the plate on the inside. Is that right?

Thanks again for your help.

[David Tilston]

No, up front there was just the plates, and the bandage. I think the point of the wood was to bond the table back splash to the shell. This would make the whole trailer stiffer. But the screws in the wood almost fell out. The wood had been exposed to water with no paint or any preservative. In the gap between the top and bottom, it had rotted right through to the inside. This piece of wood was only used on the 4500. The 1300 was metal plates and bandage all the way around.

I have watched Reece Thoen join the top and bottom half's of a new Trillium / Outback. It is basically the same process as the 1970's Trilliums, except they use a washer now, instead of the plates. I hope they use a stainless steel washer, but I don't know. It is a slow process. They set the top on the bottom, separated by thin bits of wood to maintain the gap. Then they wrestle the two half's together. On my 4500, in the corners, the plates were doubled up and closely spaced. I suspect that is where most of the work is. Once the corners are lined up, the sides are probably easier.

Originally Posted by Francesca Knowles

This is most interesting, David. If you know, is there a similar arrangement up front?

I had wondered how the two shell halves stayed "in place" with the necessary gap until the bellyband plates/rivets/fiberglass strips were applied, and this might answer that question in my mind.

Thanks!

[hrose414]

I was just at the fiberglass shop talking with the guy there and he asked why is it necessary to fiberglass the outside, could you not just bondo the 2 halves together after removing the washers & rivets? Then sand, prime & paint.
Sounded like a good point. Be a lot quicker than fiberglassing it. I'm sure I read somewhere that it's not structural anyways since the inside is fiberglass was over where the belly band washers on the inside are.

[Francesca Knowles]

Originally Posted by hrose414

I was just at the fiberglass shop talking with the guy there and he asked why is it necessary to fiberglass the outside, could you not just bondo the 2 halves together after removing the washers & rivets?
Sounded like a good point. Be a lot quicker than fiberglassing it. I'm sure I read somewhere that it's not structural anyways since the inside is fiberglass was over where the belly band washers on the inside are.

I disagree with the "not structural" part of that statement and think that joint needs as a minimum the strength of the fiberglass cloth/fibers, especially since/if all rivets and washers have been removed.

I have mixed feelings about assertions that the joint will hold long term without the support provided by the washer arrangements...that aside, I certainly wouldn't rely only on the original inner thin layer of fiberglass to do the job, faced on the outside only with Bondo.

[David Tilston]

That inside bandage is a pretty thin sheet of fibreglass, but it is all that is attaching the top to the bottom under normal circumstances. It would probably be fine with just bondo, but I doubt using fibreglass instead of bondo is much more work, (I found it really fun) and the end result is also likely stronger and less prone to cracks.

On edit: I doubt that the metal plates, rivits, and belly band add anything to the structure. On my first belly band thread, many of the plates had rusted out completely, and the belly band was falling off.

The cost was minimal, like less then $100.

[hrose414]

I do agree with having added strength, and if it's not tough then I would rather go your way. I haven't fiberglassed before and want to do it myself and have it look good. David did you find there was a bulge where you fiberglassed, or did you grind the Fiberglass down around the spot where you attached to keep it flush? Does that make sense? Obviously I will have to sand the gel coat down to have something to adhere the Fiberglass to, I just want it to look smooth. Do you have any pictures?
Cheers

[David Tilston]

If there was a bulge, I ground it down. In some cases, that meant that the metal plate fell right out. I was looking at the first trailer I did this on. I am amazed how well it worked out. Since I went around grinding the top, then the bottom till the gell coat was exposed, there is just the slightest of peak in the middle. Some time with the orbital sander, and the whole thing is almost ready for paint.

I think I did a better job the second time, but that trailer is still in Ontario.

[Scott H]

I did the bondo version of this project a few years ago (see the bye bye belly band thread); here's my take away. David's glass method will be ultimately stronger. The bondo method is faster (weekend project) and, in my opinion, it's stronger than the original construction. But not much. After a couple years my repair looks great, but time will tell.

[hrose414]

Thanks Scott that does look good! When you went to repaint it after doing that bondo job did you need to remove the gel coat from the entire trailer or do you just paint over the existing gel coat?

[Doug2000]

I would not use bondo at all. It's not at all structural, it's a great filler, that's it. When your screaming down the highway and hit the railway tracks a little to fast, you want that belly band to be strong. Bondo will just crack.

When you apply fibreglass, make sure it is Polyester Fibreglass. I bought mine in bulk at the Marina Repair Shop. Only apply it to virgin clean original fibreglass. I ran into a problem when fixing my floor, I had a little glue I didn't get off and it prevented a proper cure.

Do it right with compatible materials so if you have to come back its easier to fix later. If you just use Polyester Fibreglass then you won't have compatibility problems.

[David Tilston]

I think the way I did it is stronger, but if using Bondo works, and lasts, who cares? There is not only one reason I do it with fibreglass, but several. It may be mainly that I really like grinding and laying down fibreglass. Really therapeutic for me.

I have four more belly bands to go, probably more in the future. I will still use fibreglass. I am a slow worker. I think I could do it in a weekend, if my kids did not require my attention, and the moons are aligned. But since I only put an hour or two in at a time, it takes longer.

Time estimates:
Prep, (news paper): 1 hour
Grinding: 2-3 hours
Removing the metal plates: 4 hours
Grinding the sockets: 1 hour
Laying the glass: 4 hours
Grinding back to the gel coat: 3 hours
Sanding flat: ??? haven't done it yet
Bondo: ???
Sanding: ???
Painting: ???

An estimated 16 hours to do what I have done. Other then the brown fibreglass showing, it looks good. I guess I am pretty good with a grinder. I think a few hours with the orbital sander and I might not need any bondo.

In preparation for launch day, I am going to do a complete referb of Launch Pad, this summer. This includes re-install the windows, re-install the door, and belly band. This time, I will try to go fast on all three. I will try to keep a log of the hours I spend.

The door was way easier then I though it would be.

[Mel P]

Originally Posted by Scott H

I did the bondo version of this project a few years ago (see the bye bye belly band thread); here's my take away. David's glass method will be ultimately stronger. The bondo method is faster (weekend project) and, in my opinion, it's stronger than the original construction. But not much. After a couple years my repair looks great, but time will tell.
Attachment 71351

4 more years and what is the verdict? Did the Bondo hold or do I need to do the fiberglassing? It is already the end of June and with 3 jobs and 2 kids, I just want to get on the road camping a few nights. Any thoughts anyone has or links to other belly band threads that are concise, please let me know. I have looked at several old ones from Dave (Thanks for your thorough work). Also would love to see video if anyone has that.
Mel

[David Tilston]

I should update this thread. I finished the Bondo, and paint. Quite the learning experience. Below is a picture of how it turned out. More pictures can be found in the following link:
http://www.fiberglassrv.com/forums/f...cdn-76798.html

[John in Michigan]

Dave, what kind of paint did you use? I'm repairing my Trillium 4500 center band now and hoping to be to the point of painting it in a couple of weeks. Thanks.

[David Tilston]

Ummm.... well.... It is actually just a sandable primer that I got at Canadian Tire. I liked the colour so much that I never painted over it. It probably wont stand up to much wear.



I was just on the Canadian Tire web site. Doesn't look like they have it any more. I might have a half empty can of it at home. I will check tonight.