Lost in the forum

[mvankanan]

Hi I'm looking for the thread where everyone says what materials and methods. I'm about to glue some foam to foam and forget what to use.

Thanks, Mike

[Stargazer]

I'm not sure this is the one you want but it has info from some of the builders.

It is on the second page of the Foamies forum titled MATERIALS POLL

http://tnttt.com/viewtopic.php?f=55&t=65718#p1165657

Gene

[KCStudly]

For foam to foam you can use Gorilla Glue (GG... the dark brown expanding stuff), or Great Stuff (GS) that you knock down after spraying it out. The GS sands closer to like XPS but I always seem to have trouble with large bubbles forming (humid climate here).

PL300 is another option, but it doesn't sand or cut the same as the foam, it's more like a vinyl caulk.

[mvankanan]

Thanks

Stargazer that's the one.

KC thanks, good info on the sanding, haven't got there yet, but soon, hopefully. Is the pl 300 the one they make for foam? I was looking at all the glues in HD last night. I have a quart of GG but I was saving it for the "real build" later. Thought about using the latex caulk too, forget who used it, was tempted but it's my first foam build.

Anyone have an idea on how much GG I will use for about 50' of 2" to 2" bonding, sides to top and bottom? How about if I used the GS how many cans?

When you use the GS, do you just lay out a bead, spread it around, and push it together, and clamp?

I think I will go grab a tube of GG, do some gluing and see how far I get and not open the quart.

Mike

[GPW]

Mike , since all of us have slightly different methods and results , we’ve found it’s best to test all your adhesive and materials , on small scrap pieces first , just to assure your self that it really works like you want it to ...

Ps. and while gluing up foam panels , it’s perfectly acceptable (recommended) to use Bamboo skewers as rudimentary “Pins" to hold the panels together ... you can remove them later or just saw them off level and they become part of the construction , and a slight bit of extra bracing too ...
The thing is , no matter what glue you use for construction , it will only be as strong as the Foam it’s glued to ... which is not really that much .... the Canvas skin holds everything together like a giant “SOCK” .... The main principle of foamie' construction ... Foam is just mostly air ( and a bit of bubbly plastic eh ! ) , the “skins" , give it strength ...

[mvankanan]

[quote="GPW"]Mike , since all of us have slightly different methods and results , we’ve found it’s best to test all your adhesive and materials , on small scrap pieces first , just to assure your self that it really works like you want it to ...

I should be gluing in 15 mins, going with the GG, bought 2 small 4oz. bottles, supposed to have a min coverage of 48' of 2".


Ps. and while gluing up foam panels , it’s perfectly acceptable (recommended) to use Bamboo skewers as rudimentary “Pins" to hold the panels together ... you can remove them later or just saw them off level and they become part of the construction , and a slight bit of extra bracing too ...

Maybe I should run out for some for alignment, I went out and bought 4 3' clamps.


The thing is , no matter what glue you use for construction , it will only be as strong as the Foam it’s glued to ... which is not really that much .... the Canvas skin holds everything together like a giant “SOCK”

I get that, I'm a bit afraid of it breaking during construction, I'd like to keep the roof off and canvas the inside first(?), actually bed sheets inside, maybe. Building a frame to keep it from flexing or jarring might be wise.

Anyway this is my practice, by the time I got comfortable with a way to build the jeep thing, and my desire to try to do some kind of decent job, (if KC is the gold standard, I'm shooting for 50% KC), I knew it would never be ready for CO in August. I also knew I wanted to practice, so back to the Suby. I'm doing a mini version for that. Need to be on the Road 24 July, was supposed to be 01 Aug.........."but we have to be there on the 28th to go camping". No holes in the roof, but I did get rid of the hatch. Hopefully I'll get this road ready, and watertight, if not all done, maybe no side doors right now, (potato fork or hoe from the back, to rake out stuff?). If not it's the jeep as is.

Pictures pictures are still a lot of unfun for me, I will take them and when I get to CO maybe I can learn someway to get them from email to here, like the rest of the world.

A couple of serious questions, I'm basically building a 2" foam box on a couple of sled runners, I don't want to add any kind of wood blocks as attachment points at this time, I also want a roof rack of some kind. I'm thinking of using a strip of wood, maybe 3/8 ply, on the inside over the wood runners, and bolting through this, this will save me from routing and mostly locating where the bolts should go, kind of fussy work when pressed for time, they can go any where. So the strip of wood is kind of like a continuous washer. For the rack I was thinking wood strips inside and out and through bolted, down and dirty, but should work?. Across the front, someone mentioned, some where, about nylon fender washers and through bolting I'm planning on that. They 50% KC is for the jeep build (ETD FEB 17) this could go lower Would appreciate any feed back on this scheme.

This box will attach to a wood frame built on a 2x4 frame attached to the roof and trailer hitch. New rear hatch will attach to this frame. Kind of interesting trying to do this, hopefully someday I will meet a pattern maker and he can show me how I should have done it!

Mike

[KCStudly]

Please don't use my build as a judge... okay, if you must I guess it is okay .... but if you consider that it looks like I am on a 5 year plan (my 4th annual deadline has come and gone), then 50% KC is still 2-1/2 years of steady part time work, or about 2400 man hours of labor (well over 1 man year full time).

These things take time, at least for me. YMMV.

There have been many fine TD's built in less than 4 yrs, still fewer really nice ones built in less time. I don't know how they do it.

[ghcoe]

Thought about using the latex caulk too, forget who used it, was tempted but it's my first foam build.
Mike

I have been using the latex caulking in my build. It seems to set up a good bond once dry to the touch on the edges, but does takes a long time to cure completely through. I like using it now better than GG or GS. Mostly because it does not foam and create a hydraulic lift or push on the parts being bonded together or foam out in places that you need to clean up later. It is also more economical than GG and GS. Good luck.

[mvankanan]

[quote="KCStudly"]Please don't use my build as a judge... okay, if you must I guess it is okay ....

It seems to me you got craft, design, and engineering down pretty good, that's pretty admirable.................maybe after 5 years you should wish I had 5 weeks.

What I'm doing should be a lot simpler....except for the connection to the vehicle, which I'm puzzling through. I just know there are ways to think about that, and bags of tricks that I know nothing about.

If I don't shoot kinda high, I can end up with a bag of poop, pretty quick.


but if you consider that it looks like I am on a 5 year plan (my 4th annual deadline has come and gone), then 50% KC is still 2-1/2 years of steady part time work, or about 2400 man hours of labor (well over 1 man year full time).

I would like to do something with that kind of commitment, I'm thinking a proa, or other small sailing canoe. Place to do it is a problem, since it is so long term.



Mike

[mvankanan]

Thought about using the latex caulk too, forget who used it, was tempted but it's my first foam build.
Mike

I have been using the latex caulking in my build. It seems to set up a good bond once dry to the touch on the edges, but does takes a long time to cure completely through. I like using it now better than GG or GS. Mostly because it does not foam and create a hydraulic lift or push on the parts being bonded together or foam out in places that you need to clean up later. It is also more economical than GG and GS. Good luck.

I can see how that might work, I've tried pulling wood apart with that stuff on there! All it has to do is keep the foam in place, the fabric is what holds it all together.

How long before you can apply the fabric?

Because I have angles and compound angles, I used a skill saw and guide to cut the foam, just a bit of wave in the saw or bend in the foam can form a little gap, I didn't want to try and sand the whole 8' edge flat, I never worked with GG, will that fill little gaps, or do the surfaces have to be touching completely, like edge gluing of wood? It seems that the caulk would handle small gaps, and gouges pretty good. I'm talking about less then 1/16" for several inches.

I never glued last night, so I could switch to caulk. I rigged up a table and a kind of top to hold the sides and bottom together, while clamping, and applying fabric to the insides of the top and bottom. It will be pretty small inside once it is done, so I'd like to get the fabric at least glued on the inside where I can.

Mike

[GPW]

M, if it’s any easier , you can do all the insides flat on a table , and then assemble them , the fabric does not interfere with adhesion and may actually help , and you can trim it off neatly on all the assembly edges If you want ... and we’re still big on using “reinforcing strips" , which help the inner and outer skins tie together better , the the walls, floor , and roof as a single unit ...
Technically , you could cover each panel inside and out , and then glue them all together as a unit ... Many ways to build a Foamie trailer ...

You know , it’s easy to make a scale model out of recycled corrugated cardboard ( 1” = 1’ ) ... Great way to get a handle on things ... Cheap and fun ( great rainy day activity )

[mvankanan]

M, if it’s any easier , you can do all the insides flat on a table , and then assemble them , the fabric does not interfere with adhesion and may actually help , and you can trim it off neatly on all the assembly edges If you want ... and we’re still big on using “reinforcing strips" , which help the inner and outer skins tie together better , the the walls, floor , and roof as a single unit ...
Technically , you could cover each panel inside and out , and then glue them all together as a unit ... Many ways to build a Foamie trailer ...


Won't you be mixing different adhesives, titebond II for the fabric and something else GG for the foam, any problem with that?

I'm assuming you don't paint till after.

This could be a time saver, but I think I can build it as a three sides box and then add the fabric and run it up the sides in one shot, maybe do the top seperate.



You know , it’s easy to make a scale model out of recycled corrugated cardboard ( 1” = 1’ ) ... Great way to get a handle on things ... Cheap and fun ( great rainy day
activity )

Well the problem with that is I don't have any place to measure the car from so the measurements aren't any good, need that bag of tricks I did a bit of industrial concrete forming, machine bases, big ball mills and such. we would spend a day cutting notches in the steel above and stringing piano wire all square and level, you kind of worked upside down but you could measure anything inside the grid. " Ain't building houses kid, we measure in thousand's " said the millwright ramrod.

I used to be ok with isometric drawings, most things that are angular I can draw to scale and work our details, I don't quite know how to do it with the car.

Goto go getting bumped from the computer. Mike

[ghcoe]

How long before you can apply the fabric?

I never worked with GG, will that fill little gaps, or do the surfaces have to be touching completely, like edge gluing of wood? It seems that the caulk would handle small gaps, and gouges pretty good. I'm talking about less then 1/16" for several inches.

Mike

I am not sure how long till you could attach fabric. Lots of variables there and I do not even know if it would matter. The test piece I did was two 2" pieces of foam bout 8"x8" square. I glued them together one day and then tried to separate them the next day. The two pieces would not separate by hand at that point. I cut the piece in two and found that the inside caulk had not cured yet and at that point I was able to get ahold of the non cured side and separate the two pieces. The caulk had cured towards the middle about 1" in from the outside edges. At that time the foam gave away before the bond did along the cured edges. I let the other piece which now was 4"x8" cure for a week. I cut it in two and found that the caulk had completely cured to the center. How long it really took to cure the final 3" I could not tell you, but I would suspect that since it cured in from the edges 1" during 24 hours that on 2" thick foam in should be good in 24 hours.

The problem I have with GG, besides the hydraulic effect, is that it is harder than the foam so when you go to sand it the foam sands faster than the GG this leaves high spots. I finally took a dremmel and sanded the GG below the surface of the foam and then sanded the foam. I filled the low spot later with light weight spackle and finish sanded. Small gaps caulking would fill just fine, not sure if I would fill gouges though. I use light weight spackle for surface gouges.

GS is easier to work with than GG in my opinion. It sands easer, but is really messy to work with.

Caulk seems to fit the bill for everything I have done now. I think I would even use it for the wall to floor glue up. It is easy to work with, easy to clean, does not push parts apart and smells better.

It really does not matter how strong the glue is. The weak point is the foam. In all my tests the foam was the point of failure.

[mvankanan]

I edged glued two sides to the bottom with latex caulk, a bit of a scramble, made a mistake with my spreader thing, but it still worked, didn't really have enough clamps, only had 12 4' er's It's a little off on the sides, they over hang the bottom in a few places but only by about 3/16". All in all it went ok for the first time, assuming it stays together, I think I know what to do if I was to try to get it closer.


But what I wanted to say was I checked with HD for OOP'S $9 per gal, ran a freecycle add, got 3 responses since yesterday so it looks like I can get what I need. Probably everyone else does it already, but I thought I would pass it on

Mike

[mvankanan]

Hi I unclamped my carrier, I used the latex caulk, It failed, I let it dry for 3 days. This was edge glued sides to a full sheet bottom. Not sure what happened I even ran the wall paper thing on the foam. I've tried to pull wood to wood apart with that stuff on there it just don't wont to let go?. It must have flexed, but I would have expected that stuff to have a bit of flex?

I'm out of time, I'm going to glue the fabric to the inside of the foam, then glue the panels together, so it will be fabric to fabric? Someone mentioned trying that? Like to find the thread or here from someone who has used this method. I will use TB11 for fabric to foam, what should I use to glue the fabric to fabric joint together?

Anyone think this is a bad idea?

Mike