"Old Man's Toy" offroad teardrop trailer
- Thread starter old_man
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I recently read an article about a trailer rebuild. It was a pretty serious build and I think in Oz. They originally used VHB tape to glue panels to the support structure. I searched around and couldn't find the article. Anyway, for the rebuild they chose to use sikaflex. The problem with tapes is one of tolerances between surfaces that need to stick together. The advantage to sikaflex was gap filling. It was the best real world example that I have seen for why one should consider such adhesives. I've seen other articles where guys used it in place of rivets. Not cheap, but good stuff from what I understand.
On my next build I'll still most likely use mechanical fasteners. I like powder coat and I'm not sure that any of the adhesives would handle the heat from powder coating.
I recently read an article about a trailer rebuild. It was a pretty serious build and I think in Oz. They originally used VHB tape to glue panels to the support structure. I searched around and couldn't find the article. Anyway, for the rebuild they chose to use sikaflex. The problem with tapes is one of tolerances between surfaces that need to stick together. The advantage to sikaflex was gap filling. It was the best real world example that I have seen for why one should consider such adhesives. I've seen other articles where guys used it in place of rivets. Not cheap, but good stuff from what I understand.
On my next build I'll still most likely use mechanical fasteners. I like powder coat and I'm not sure that any of the adhesives would handle the heat from powder coating.
old_man
Adventurer
Which formula? 221 looks pretty common but they have many versions. It is way cheaper than the SEM adhesive.
Found the article that I was thinking of, but am now thinking you may have read it. This was posted in your thread asking about adhesives. On the following page, skip to the paragraph heading of "Fastening". It has info. about which flavor of Sika to use.
I'm going to bookmark this page. It seems to be good info.
http://www.robgray.com/graynomad/wothahellizat/wot2/diaries/diary_19/index.php
From the article:
Fastening
Last time we used 3M VHB (Very High Bond) double sided tape to fasten the sheets.
It worked well but on Wothahellizat 2 we're using Sikaflex. There are a few reasons for this.
Firstly, when I was dismantling the old body I had a hell of a time removing the panels that were fixed with VHB but at least it was possible with hand tools. However the single panel that was glued on with Sikaflex (for reasons that escape me now) was impossible to remove manually. I had to rip it off with a fork lift.
Next there's the surface preparation. Unlike the standard double-sided (or "mirror") tape that's fairly thick and a little spongy, VHB is only 1mm thick and has no give at all. Therefore the surface has to be almost perfectly true or there will be gaps between the frame and the sheet.
This is difficult to achieve.
Sikaflex on the other hand can be globbed on in just about any thickness, so I don't have to grind every weld perfectly flat and I can adjust the thickness to ensure that adjoining sheets meet evenly.
VHB sticks instantly, you only get one chance to position the sheet. If you place the sheet and immediately realise it's not quite right you can remove it but you ruin the tape because half will stay on the frame and the other half will come away with the sheet. If you don't notice an error until after a few minutes during which time you've pressed the sheet home and maybe helped it along with a rubber mallet, bad luck, you'll ruin the sheet if you try to remove it.
Sikaflex on the other hand takes several minutes to go off, plenty of time to adjust the sheet's placement.
Using Sikaflex
Firstly, which Sikaflex to use? I asked several people, including some in the truck body building game, and they all said 227.
Then I looked on the Sika website, They state quite clearly that 252 is the recommended product for panels on truck bodies. I rang Sika here in Australia and got the same answer so that's what I'm using.
They also state that the area to be glued should be cleaned with their 205 cleaner and primed with 210 primer.
Now maybe they just want to sell more products, but I think it makes sense to follow the party line, so that's what I'm doing.
I apply the glue very liberally and try to ensure that just a little squeezes out from around the edge of the sheet. I then resist the urge to wipe the excess or clean up in any way, do this and you will spend the next half hour with black sticky crap everywhere, several rags stuck to your fingers, and a worse mess than you started with. Let it dry, it's easy to cut off with a knife.
Clamping. Sikaflex provides quite a good bond immediately, even a large sheet will stay in place and will not fall off the frame once it has touched the glue. So I find that minimal clamping is required, certainly you should not clamp too tightly as this will expunge the glue from the clamped area.
The sheet will however slide downwards and this has to be addressed, but not by clamping. With a large sheet I feel that the force required to hold it up by clamping alone is too great. Also you need to be able to rest the sheet in position several times while cutting and trimming it to shape. Therefore I feel that some simple support is required and I've made a few widgets that I can clamp to the body in various ways to provide "platforms" to rest the sheet on. These stay in place until I feel that the glue has set enough to support the sheet.
I'm going to bookmark this page. It seems to be good info.
http://www.robgray.com/graynomad/wothahellizat/wot2/diaries/diary_19/index.php
From the article:
Fastening
Last time we used 3M VHB (Very High Bond) double sided tape to fasten the sheets.
It worked well but on Wothahellizat 2 we're using Sikaflex. There are a few reasons for this.
Firstly, when I was dismantling the old body I had a hell of a time removing the panels that were fixed with VHB but at least it was possible with hand tools. However the single panel that was glued on with Sikaflex (for reasons that escape me now) was impossible to remove manually. I had to rip it off with a fork lift.
Next there's the surface preparation. Unlike the standard double-sided (or "mirror") tape that's fairly thick and a little spongy, VHB is only 1mm thick and has no give at all. Therefore the surface has to be almost perfectly true or there will be gaps between the frame and the sheet.
This is difficult to achieve.
Sikaflex on the other hand can be globbed on in just about any thickness, so I don't have to grind every weld perfectly flat and I can adjust the thickness to ensure that adjoining sheets meet evenly.
VHB sticks instantly, you only get one chance to position the sheet. If you place the sheet and immediately realise it's not quite right you can remove it but you ruin the tape because half will stay on the frame and the other half will come away with the sheet. If you don't notice an error until after a few minutes during which time you've pressed the sheet home and maybe helped it along with a rubber mallet, bad luck, you'll ruin the sheet if you try to remove it.
Sikaflex on the other hand takes several minutes to go off, plenty of time to adjust the sheet's placement.
Using Sikaflex
Firstly, which Sikaflex to use? I asked several people, including some in the truck body building game, and they all said 227.
Then I looked on the Sika website, They state quite clearly that 252 is the recommended product for panels on truck bodies. I rang Sika here in Australia and got the same answer so that's what I'm using.
They also state that the area to be glued should be cleaned with their 205 cleaner and primed with 210 primer.
Now maybe they just want to sell more products, but I think it makes sense to follow the party line, so that's what I'm doing.
I apply the glue very liberally and try to ensure that just a little squeezes out from around the edge of the sheet. I then resist the urge to wipe the excess or clean up in any way, do this and you will spend the next half hour with black sticky crap everywhere, several rags stuck to your fingers, and a worse mess than you started with. Let it dry, it's easy to cut off with a knife.
Clamping. Sikaflex provides quite a good bond immediately, even a large sheet will stay in place and will not fall off the frame once it has touched the glue. So I find that minimal clamping is required, certainly you should not clamp too tightly as this will expunge the glue from the clamped area.
The sheet will however slide downwards and this has to be addressed, but not by clamping. With a large sheet I feel that the force required to hold it up by clamping alone is too great. Also you need to be able to rest the sheet in position several times while cutting and trimming it to shape. Therefore I feel that some simple support is required and I've made a few widgets that I can clamp to the body in various ways to provide "platforms" to rest the sheet on. These stay in place until I feel that the glue has set enough to support the sheet.
old_man
Adventurer
I checked out your trailer build, that is real sweet. My wife hates tents so It had to be enclosed. The funny thing is that we are taking our Select Comfort mattress from the house and putting it in the teardrop and getting a new one for our bedroom. Nothing like roughing it ;-)
Silver dude
Xplorer
Love the metal fab good to see the absence of wood structure. Been looking at building one myself and I don't think wood and screws could take the vibration of offroad expedition duty whilst remaining light weight. Subscribed
reece146
Automotive Artist
IIRC it's effectively what type of suspension a unimog uses as well.
old_man
Adventurer
I finally found that Camper World carried the Sikaflex 252 at my local store. I'm off to get it and I am picking up $500 worth of Filon to skin it with. Dang it really adds up even at $2.75 a foot. The wholesaler said that they had some odd pieces that they would sell really cheap so wish me luck.
jeep-N-montero
Expedition Leader
We have a pair of these that I sleep better on than the $900 mattress at home http://cascadedesigns.com/therm-a-rest/mattresses/camp-and-comfort/dreamtime/product
old_man
Adventurer
I always liked the idea of having matching tires/wheels to the vic. Just makes sense. I run 35" on my trailer but now that I am stepping up to 37s on the jeep I find myself in a dilemma. I guess I'll use the small 35" trailer tires like a bicycle spare tires they put in some vics. Between the air compressor, tire plug kit, jeep spare, and open diffs (if they are not locked) I'll get by
I understand....
I see you are from Cody. I like that area. Haven't been there in about 15 years or so but we used to go and take the camper and boat to the Teton's and fish. I never failed to limit on lake trout. We would head home that way. Had to stop at the museum once or twice.
old_man
Adventurer
I snagged 4 military type fuel cans for a labor trade. These are the ones that have the screw in cap. Now I need a spout. Does anybody make one that would be compatible with a no lead filler door? If not I probably will score a 12 fuel transfer pump and just pump directly from the trailer into the Jeep.