Questions from a new builder

[Drewjharper1900]

Hey guys! So I am a first time TD builder and I have a few questions. I have been trolling the forum for the past few weeks and theres a few questions that I haven't been able to find answers too.

1. I am building a cubby 5x8 on a northern tool trailer. I will not be skinning the camper. My plan has been to construct my walls with an outer sheet of plywood, spars with foam in-between, and an inner sheet. What thickness plywood do you guys recommend for the inner and outer sheets? 1/4" or 1/2"? As well, are 3/4" spars sufficient for the walls and roof? or should I use 1"?

2. For the roof, what thickness plywood should I use for the outer layer(s)? There is no Baltic birch in my area. But there is 5.2mm White birch. Is that comparable to Baltic birch? Also, is 5.2mm the same as 1/4" or is It a little thinner? Or should I go the route of 1/8" luan? If I did use luan, is 1/8" sufficient or do I need to use 2 layers if 1/8" since I wont be skinning it?

3. What process would you recommend for sealing/painting the TD?

Sorry for all of the questions. I appreciate any input that you guys have for me!

[bobhenry]

While it's different when the FRP went on the care and maintenance of the exterior was done forever

Saved a bunch of weight final weight was 525 #


Bottom of page 1 and top of page 2 shows the spars and the frp inner and outer skin.

http://tnttt.com/viewtopic.php?f=50&t=38489&hilit=rip+van+winkle

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He is 4 years old in this pic.

[grant whipp]

Hey guys! So I am a first time TD builder and I have a few questions. I have been trolling the forum for the past few weeks and theres a few questions that I haven't been able to find answers too.

Hey, Drew!

Welcome to the sandbox!

1. I am building a cubby 5x8 on a northern tool trailer. I will not be skinning the camper. My plan has been to construct my walls with an outer sheet of plywood, spars with foam in-between, and an inner sheet. What thickness plywood do you guys recommend for the inner and outer sheets? 1/4" or 1/2"? As well, are 3/4" spars sufficient for the walls and roof? or should I use 1"?

That kind of build method is typically referred to as "stick framing" and can be a very light weight way of building a teardrop! Usually, the framing is 1x2, with the 3/4" being the thickness, and 3/4" foamboard for insulation ... 1/8" is fine for the interior, but there's really no reason to go any thicker than 3/8" for the exterior sheathing, and 1/4" is actually fine! However, one of the things that few people think about when starting on their build is the aluminum molding you will (or won't) be using to trim the door and door opening and galley wall tops, as well as which kind of door hinges you will be using. You should make the overall thickness compatible with what ever is available, or be willing & able to cut something wider down to fit. As well with the door hinges ... for instance, the custom-formed door hinges that I make & sell can't be bent for thicknesses of more than 1", and if you will be using T-Molding on your doors, you should really consider some way of offsetting the door 1/8" outward so that it will seal evenly all the way 'round (a simple 1/8" spacer on the body side mounting of the hinge will usually suffice).

Regarding the roof spars, on a 5' wide trailer I would suggest a thickness of 1-1/2" ... I would typically use 2x2s (1-1/2" x 1-1/2") on approx. 16" centers (no real reason to go any closer on spacing).

2. For the roof, what thickness plywood should I use for the outer layer(s)? There is no Baltic birch in my area. But there is 5.2mm White birch. Is that comparable to Baltic birch? Also, is 5.2mm the same as 1/4" or is It a little thinner? Or should I go the route of 1/8" luan? If I did use luan, is 1/8" sufficient or do I need to use 2 layers if 1/8" since I wont be skinning it?

I think you'll find it a whole lot easier to get the wood around the curves if you use two layers of 1/8" ... be sure to run the "grain" side-to-side so it will take the bends that much easier!

3. What process would you recommend for sealing/painting the TD?

That will depend on the overall finish you are after ... if you want a really nice-looking woody, the best and most maintenance-free method is a couple of coats of clear epoxy followed by three-or-more coats of automotive clear ... if you are looking for something inexpensive and purely functional, then smoothing and filling and sealing and finally painting with at least two coats of exterior latex paint will work just fine (if it's good enough for the wooden workboats of the Northeast, it'll be good enough for a utilitarian teardrop ... ...!).

Sorry for all of the questions. I appreciate any input that you guys have for me!

No problem ... that's what we are all here for ... ...! Good Luck on your project, and as always ...

CHEERS!

[Pmullen503]

Snip....

That will depend on the overall finish you are after ... if you want a really nice-looking woody, the best and most maintenance-free method is a couple of coats of clear epoxy followed by three-or-more coats of automotive clear ... if you are looking for something inexpensive and purely functional, then smoothing and filling and sealing and finally painting with at least two coats of exterior latex paint will work just fine (if it's good enough for the wooden workboats of the Northeast, it'll be good enough for a utilitarian teardrop ... ...!).

No problem ... that's what we are all here for ... ...! Good Luck on your project, and as always ...

CHEERS!

All good points but will your tear be stored outside most of the time?

Based on my experience with wooden boats, if you plan to use lumber yard plywood (as opposed to true marine grade ply) I would recommend either glass cloth under epoxy with a good UV resistant varnish or canvas and glue under latex paint. Either way, glass cloth or canvas the seams at least. Both of those options will dramatically reduce the long term maintenance if you must store it outside.

[Drewjharper1900]

That kind of build method is typically referred to as "stick framing" and can be a very light weight way of building a teardrop! Usually, the framing is 1x2, with the 3/4" being the thickness, and 3/4" foamboard for insulation ... 1/8" is fine for the interior, but there's really no reason to go any thicker than 3/8" for the exterior sheathing, and 1/4" is actually fine! However, one of the things that few people think about when starting on their build is the aluminum molding you will (or won't) be using to trim the door and door opening and galley wall tops, as well as which kind of door hinges you will be using. You should make the overall thickness compatible with what ever is available, or be willing & able to cut something wider down to fit. As well with the door hinges ... for instance, the custom-formed door hinges that I make & sell can't be bent for thicknesses of more than 1", and if you will be using T-Molding on your doors, you should really consider some way of offsetting the door 1/8" outward so that it will seal evenly all the way 'round (a simple 1/8" spacer on the body side mounting of the hinge will usually suffice).

So in the case of your hinges, for a stick framed door, would a 1/4" outer layer, 1x2 framing, and a 1/8" inner layer work with them? I know that adds up to a total of 1-1/8". If that wouldent work, then how do you get the thickness down to 1"?

[Drewjharper1900]

All good points but will your tear be stored outside most of the time?

Based on my experience with wooden boats, if you plan to use lumber yard plywood (as opposed to true marine grade ply) I would recommend either glass cloth under epoxy with a good UV resistant varnish or canvas and glue under latex paint. Either way, glass cloth or canvas the seams at least. Both of those options will dramatically reduce the long term maintenance if you must store it outside.

Being that I am trying to keep the budget down for this build, I was not planning of fiber glassing the entire camper. But I do like the idea of glassing the seams!

[Pmullen503]

Remember, a few years from now you won't miss the money or time you spent being fastidious about waterproofing. You will regret taking shortcuts to save a few bucks or hours of work when you are faced with a repair.

[grant whipp]

That kind of build method is typically referred to as "stick framing" and can be a very light weight way of building a teardrop! ...

So in the case of your hinges, for a stick framed door, would a 1/4" outer layer, 1x2 framing, and a 1/8" inner layer work with them? I know that adds up to a total of 1-1/8". If that wouldent work, then how do you get the thickness down to 1"?

Hi, Drew! You could shave away the 1/8" paneling from just under where the hinges mount ... that would get you the 1" net thickness. However, if you choose to frame with 1x2s, you wouldn't really need my Formed Offset Hinge ... you could just screw the hinge leaves directly into the lumber (leaves between the door framing and door opening framing) (my offset hinges were really designed more for plywood core construction, so that you don't screw into the end-grain of the plywood).

All good points but will your tear be stored outside most of the time?

Based on my experience with wooden boats, if you plan to use lumber yard plywood (as opposed to true marine grade ply) I would recommend either glass cloth under epoxy with a good UV resistant varnish or canvas and glue under latex paint. Either way, glass cloth or canvas the seams at least. Both of those options will dramatically reduce the long term maintenance if you must store it outside.

Any plywood you use on the outside of a trailer should be at least Exterior Grade ... while Marine Grade is probably the best stuff out there, the glue is exactly the same as Exterior Grade, the only difference being the quality of and number of the inner plys. And, while I do agree that epoxy & 'glass is probably the best, longest-lasting, and most maintenence-free way of finishing a woody, the simple latex finish can last you a lifetime if the unit is properly prepped, maintained, and regularly re-finished (re-finishing is as simple as wire-brushing off the old scaling paint and re-covering with one or two more good coats. I've seen 60+ year-old teardrops that were finished this way, and they held up just fine as well s looked decent to boot.

Bottom line is, go with whatever you can afford ... and if you want/need something that might be a little out of your price range, just save up a little longer and take just a little more time ... it'll be worth it in the long run ... ... ! Continued Good Luck, and as always ...

CHEERS!

[pchast]

Welcome and
Good Luck with your build.

[Drewjharper1900]

Fortunateley I have a shop to store it in so it won't be outside unless we are on a trip.

[Jdw2717]

Grant nailed it. Mine is 1/4" outside, 3/4" framing and 1/4" inside with the white foam board insulation for the walls. The roof and curved front along with the hatch are single layer of 1/8" inside, 1.5" x 1.5" spars (2" x 4" ripped in half) and single layer of 1/8" outside with two layers of foam as insulation. I opted to not go with the fiberglass since mine is stored in a garage unless in use. I used a good quality oil based primer and then a latex house paint for ours. Two and a half years later and 5000 plus miles and it still looks great. Good luck with your build and ask lots of questions. We all started with little know how and gleaned all we could from the board members.