Weight of plywood

[asianflava]

That is the exact problem I spoke of above before folks said "the cost"

10-4 I see it now. The cost AND no framing are reasons enough for me not to bother.

[BobR]

It is a great debate...to insulate or not. I have considered both. On my tear I simply used 3/4" ply. I have always thought if I built another I would use an insulated type of construction...but then I realized that I am not going to live in the trailer, just use it for camping so I would again opt for the simplicity of using a single sheet of plywood. You can spend a lot of time and money building walls OR you could go camping

[angib]

There's a law that says in any sandwich structure, you'll have at least one major thing to fix to it that you didn't know about when making the panels - so you didn't build in a block to fix it to.

This is how composite boatbuilders deal with this:
- Drill a hole where the fixing will go.
- Insert an allen key* through the hole and twist it to stick in the foam.
- Put the exposed end of the key in the chuck of a drill.
- Use the drill to whirl the key round, creating a cylindrical void between the two skins.
- Inject filled epoxy resin into the void.
- Once the resin is set, re-drill and bolt the fitting through the pad.

This only works where you can bolt right through - as no-one has yet invented INJECT-A-WOOD®, you can't drive a screw into the pad!

If you're really weight-obsessed, like racing yacht builders, you can put a separate tiny pad in for each fixing!!

Andrew

*Allen key = L-shaped piece of hexagonal stock, for turning allen screws - is this a 'hex wrench' in Merka? I'm sure one of the Canuckians will know the correct translation.

[LashleyT]

The main reason I posted the thumb rule of 48.3 lb per cubic foot was to show people that have small cars or trucks (like myself, Honda CRV) that can only tow up to 1500 lbs that you can build a 4x8 out of plywood well under 1500 lbs. If you use say 5 sheets of 3/4 in plywood, that's 10 cubic feet which is 483 lbs add 250 for trailer and another 100 lbs for supplies you are some where around 833 lbs! - Tom

[asianflava]

*Allen key = L-shaped piece of hexagonal stock, for turning allen screws - is this a 'hex wrench' in Merka? I'm sure one of the Canuckians will know the correct translation.

We call them allen keys or allen wrenchs, a generic name because they were trademarked by the allen company. Like "Cresent wrench" originally made by the cresent company.

[mikeschn]

This only works where you can bolt right through - as no-one has yet invented INJECT-A-WOOD®, you can't drive a screw into the pad!

One of the things I was thinking about was drilling a 1/8" hole thru...

then counterboring a larger hole, equal to the size of a dowel (1"?) thru 1 wall and the foam.

Plugging the counterbore with the dowel, sanding it flush, and putting in a screw.

If it's on the outside you can paint it.

If it's on the inside you can stain it!

Maybe I'm all wet. If I am I'm sure you'll set me straight.

Mike...

[angib]

Mike,

That way, all the load would be taken on the one continuous skin and possibly with the glue in tension. Then there is the joint between the cut skin and the plug, which is just dying to become a circular crack as soon as the 'pad' is loaded up.
Apart from that, the idea's great........

Andrew the idea assassin

[Guy]

Andrew is BAAAAACK!

[mikeschn]

Andrew is BAAAAACK!

Ah you are right Guy, I negelected toast to the fact that our idea assassin is back... cheers

Seriously though, it's good to have you back Andrew... we've been saving up all these really good questions for you... hope your up to it now that you are rested and perhaps a little bit teardrop deprived!

BTW, didn't you say you were going to share a photo of a horse trailer with us?

Mike...

[angib]

BTW, didn't you say you were going to share a photo of a horse trailer with us?

Yup, I did - but the plan was spoilt by failing to pack the camera!

Andrew the bear of little brain

[Mitheral]

This only works where you can bolt right through - as no-one has yet invented INJECT-A-WOOD®, you can't drive a screw into the pad!

Lots of machinable epoxies out there though. I'm not familiar with any that are injectable but I'm sure someone has to make one. Proceed as outlined then once the epoxy has hardened drill and tap for a bolt. Viola, non through attachment point where ever you want one. This might be a real superior method of attaching fenders to a teardrop body.

[weasel]

I bought a set of scales to weigh my project. Weighed the steel, axle etc. Heres my ply weights... 3/4 70#.... 5/8 60#.... 1/2 40#.... 3/8 35#.... 7' 2x4 9# ripped for 2x2's. The boards I forgot to weigh was the 1x4 used for cabinet faces. All shelfs are the leftovers,from the 5/8 and 1/2.