YET ANOTHER PMF QUESTION? ... NOT! ...

[fm-usa]

First, I would like this thread to keep within the boundary of information and pictures of said info, not chit-chat or off thread postings.
Reason? Not interested in sifting through thousands of posts for 'X' info.
Possibly use the same particular short TITLE your posting for easier searches.
Whoever starts a TITLED thread, others please keep the same TITLE.
[eg's]
DACRON
DACRON CANVAS
CANVAS RAYON
CANVAS FOAM CANVAS . . . etc..

* * * ON WITH THE SHOW * * *

In this thread how many different ways and materials have folks used PMF?
What worked and didn't?
What material was weakest, strongest, lightest and heaviest?
How well did or didn't paint stick to "X" material?

What number of layers worked and didn't? [I'm VERY interested in this one]
Of said multi layers,...
What were the weights?
Were they good for very thin interior walls? Any known loads? Failures?
Was PMF useful as shelves? If so what loads did it carry? Ant internal supports?
Said loads, did it hold up over time?

Was "IT" easily repairable or replaceable?

I can go on-and-on but hopefully you get the gist of this thread.
Maybe think of this a mini encyclopedia of PMF.

Lastly, if this was done already, please delete this thread.

[fm-usa]

CANVAS

I'll start this thread.
Of the many thicknesses and densities (thread count) of canvas, what was the lightest yet marginally strongest canvas?
Were any particular canvases not suitable with Tight Bond 2 (TB2)?

[rowerwet]

My plywood tear has 10 oz canvas, glued on and sealed with exterior porch paint. Tough strong and fine after 5 years.
My attic hatch is bed sheet cotton over plywood, glued on with TBII and sealed with exterior house paint. Two years on the roof with no issues.
The church steeple is coated with 10 oz canvas, stuck and coated with exterior paint. It is on its second new England winter, with no issues.
My first foam kayak is also coated with cotton bed sheets. I used full strength TBII to stick it, and exterior house paint to seal it. One season of paddling has revealed that bed sheets over foam can be punctured by sharp impacts on pointy objects. These all happened while moving it around on land.
Another issue is that I used a synthetic blend fabric on one section, the more I used the boat, the more and bigger the blisters in that section have become. This section is also loosing bits of paint. It seems the paint didn't fill into the fabric the way it does with 100% cotton.
I believe PMF must be done with a natural fiber that will absorb some of the glue and paint to get the best bond.
My current foamie has 8 oz canvas glued on with 25% thinned TBII, sealed withexterior house paint . I do not recommend doing PMF with thinned tbii, it doesn't bond as well as full strength, doesn'tget tacky quickly enough, and isn't as strong. That layer of glue is extra strength IMO.
I believe foam needs the strength of canvas to protect it, from punctures.
Any areas that have extra TBII that dries onto the surface of the fabric, dries with a surface that paint does not stick to very well.
I have never tried more than one layer of fabric, not sure what that would accomplish, or how to stuck it all together, unless you stuck the first layer to the second with paint.
Paint is heavy, roughly half of the can wet weight, one layer of painted canvas will wear like iron

[fm-usa]

Thanks rowerwet.

My plywood tear has 10 oz canvas, glued on and sealed with exterior porch paint.
One season of paddling has revealed that bed sheets over foam can be punctured by sharp impacts on pointy objects. These all happened while moving it around on land.
I was considering 'Canvas Ply' (CP) it up. [Eg] 4 oz || 12 oz || 4 oz ... thoughts?
This CP I'm thinking I can use this as interior walls and cabinet frames. Might need 5 layers for shelves or a couple of Maple interior stickers as its bones.
__________
Another issue is that I used a synthetic blend fabric on one section, the more I used the boat, the more and bigger the blisters in that section have become.
You're saying Dacron, rayon or polyester should not be used?
Things I have done was glue 2 different plastics together that are not glue able.
I took a sharp blade and multi angled cut into both plastics faces giving them deep tooth to hold glue.
Another time I took one plastic and sewn melted into the other then glued.
Both systems are holding very well after several years.
__________
I believe PMF must be done with a natural fiber that will absorb some of the glue to get the best bond.
Natural fiber has natural tooth for glue to hold to, whereas man made fibers do not.
__________
My current foamie has 8 oz canvas glued on with 25% thinned TBII, sealed with exterior house paint.
I do not recommend doing PMF with thinned tbii, it doesn't bond as well as full strength, doesn't get tacky quickly enough, and isn't as strong. That layer of glue is extra strength IMO.
I read where a layer of TB2 was rolled/brushed on until dry then PMF on top of that. Is that a better way in your experience?
__________
I believe foam needs the strength of canvas to protect it, from punctures.
Maybe multi layers like plywood?

My current timeline to start my build is March-ish. Still MacGyvering up strong and lightweight ideas.
Once my build is ironed out and I'm happy with it, it just might be a trailer to build to sell. BTW, it is sorta Teardrop in shape, hence joining this website.
.
I'm doing my best to keep a Net weight of 450-ish pounds for frame and body. Then add 50 pounds for electric brakes. (All rounded numbers)
Since my build is to be pulled by motorcycle, any trailer above 400 pounds should have brakes. Cars are different and won't need brakes until 750-ish pounds. Here you folks would have a better idea what cars need than I.
Current expectations of my trailer is up to 5 adults can sleep in it or a family of 7.

[rowerwet]

For shelves I see foam as bulky, 2" foam having the same strength as 1/4" plywood. Even with layered fabric I don't think you will beat the strength of plywood. If you look in my build thread link, my galley counter is 3/8" plywood with a 1x3 frame it would take way more than it's worth to get a foam shelf to the same strength. I could've even gone lighter on the support framing if I wanted to make some epoxy/plywood laminated beams.

[rowerwet]

PMF is meant to follow the kiss idea, for the ideas you mention, I would look into sculpted, bonded, internally braced, fiberglass and epoxy wrapped, vaccum bagged construction. EDIT: carbon fiber and Kevlar instead of fiberglass.
You will have issues making a tent for 5 or 7 with the weight target you mentioned.

[Talia62]

You're saying Dacron, rayon or polyester should not be used?

Rayon is a natural fiber.

[fm-usa]

For shelves I see foam as bulky, 2" foam having the same strength as 1/4" plywood. Even with layered fabric I don't think you will beat the strength of plywood.
Shelves would have no foam (lost space), cabinets maybe for load strength. Actually we're jumping ahead here. I would need to know if anyone tried Canvas Ply, I don't have material to test it. I/we could then discuss its merits and faults.

If you look in my build thread link, my galley counter is 3/8" plywood with a 1x3 frame it would take way more than it's worth to get a foam shelf to the same strength. I could've even gone lighter on the support framing if I wanted to make some epoxy/plywood laminated beams.
I did look, looks good!
__________________
PMF is meant to follow the kiss idea, for the ideas you mention, I would look into sculpted, bonded, internally braced, fiberglass and epoxy wrapped, vaccum bagged construction.
You will have issues making a tent for 5 or 7 with the weight target you mentioned.
My design has partial soft sides but does have a solid roof like that of PMF.

My design is not a 'turn-key' style trailer, like Teardrops. There will be some setup but keeping that to a minimum. Eh, trade-offs.
Everything will be snugly packed down low during transport keeping the CoG as low as possible. Heavy stuff like battery, liquids, etc. are centered and under the trailer. The hard part is keeping all maintenance and repairs easily accessible. So far it looks like I'll be loosing some space for that convenience. I definitely do not want this to look like an American cars engine compartment.

I have acquired all the kitchen cookware in aluminum. In a cardboard box, it weighs around 10 pounds. I have a couple cast alum pots and roasters, that doubles the weight but I really like how they perform. Definite keepers.
Chromed plastic eating utensils are so light they almost float in the wind.

If I have any dedicated counters, it would be an interior hollow core door. If needed, the stress areas I'd drill holes on the underside to inject Great Stuff. These doors are cheap and easily replaceable. I stood on a 28" door and it held my 240 pounds but a door being solidly mounted begets damage from dropped objects due to thin skin.

Everything I accumulate for this trailer #1 priority is weight. I have 2 cast Alum, gym locker style double coat hooks, they weigh about that of 3 sheets of 8x11 paper. I could not believe the weight when found at a yard sale. 2 for $0.25
50 cent Flea Market find, a collapsible, closet rod hung, canvas shoe rack for instant shelves. After testing it for cookware storage it works well as long as a stiff shelf is added and CoroPlast worked nicely!
Everything loose will be tightly stored in cardboard boxes. As items change, cardboard boxes are cheap.

Whatever I plan to do on this trailer I have to keep in mind two things.
1.) For my use. [Keeping it bare minimal materials and strength]
2.) Build for sale. [Extra strength means more weight]

THANKS for the feedback. Gave me a couple ideas to ponder.

[fm-usa]

You're saying Dacron, rayon or polyester should not be used?

Rayon is a natural fiber.

YUP, my oops.
Meant Nylon.