New member, new trailer design!

[reaver]

Nice design. I have a couple suggestions for better aerodynamics. First, consider inseting you stove box so it's flush on the outside. You lose some cabinet space but you just have a door instead of a box hanging in the wind. Second, narrow the very front of the fridge box so it's narrower than the width of the tow vehicle if it isn't already.

While I appreciate the suggestion for the kitchen box, this on is staying how it's designed. It's designed to be removable, as I want to play around with prototyping a few things.

Now, the box up front.... I can certainly look into narrowing the front of the box. I'm less concerned with aerodynamics on those two parts, and they're modular and not built into the actual trailer, though I'm designing around them as well.

 

[ghcoe]

Just a suggestion. Do away with the roof vent. Just another weak point for water to get in. Also, condensation will collect there and drip on you and/or your bedding. Windows in that small a unit is more than enough ventilation. I have built in vents that don't close in mine in the side walls. Of course, they are there to keep me alive because foamies are so air tight.

 

[reaver]

When thinking about the sealing process, I had a thought. Would there be any harm in doing a hybrid between standard fiber glassing and pmf? What I'm thinking is coating with cpes to first seal the wood, then wrapping with canvas (due to cost over actual fiberglass), then coating the canvas in epoxy instead of glue.

I'm really leaning towards this method, but want to get some options from folks who have more experience than I.

 

[Pmullen503]

You should either use resin and glass or glue/paint with canvas. Each works as a system.

Resin and glass isn't than much more expensive than PMF and is more waterproof. PMF is probably more forgiving if you've never done anything like this before

Mixing components tends to give you all the disadvantages and none of the advantages.

 

[reaver]

You should either use resin and glass or glue/paint with canvas. Each works as a system.

Resin and glass isn't than much more expensive than PMF and is more waterproof. PMF is probably more forgiving if you've never done anything like this before

Mixing components tends to give you all the disadvantages and none of the advantages.

Well poop. So much for my brilliant idea. I'll stick with the fiberglass method.

 

[ghcoe]

Resin and glass isn't than much more expensive than PMF and is more waterproof.

I did the numbers on PMF over Fiberglassing just to see what the price difference really is. People always say that fiberglassing is just a little bit more than PMF so why not just Fiberglass. Well, there really is a reason it is called PMF.

Here are the numbers using the materials recommended earlier in this post for fiberglassing.

6 Yards 6oz x 60" Fiberglass $46.50
6 Yards 6oz x 50" Fiberglass $42.00
6 qt Kit Non-Blushing Epoxy $114.05
Total Before Shipping Costs and Tax $202.55

Here are the numbers for PMF.

15 Yards 60" 7 oz Cotton Duck $59.85
1 Gal Tight Bond II $26.99
Total Before Shipping Costs and Tax $86.84

I did not add in tax and shipping because that is a variable that might be mitigated by local resources. If you did however have to order in the materials the epoxy resin and fiberglass is 37.04 for shipping. I would suspect that is because it is a chemical. 15 yards of cotton duck cost 7.99 for shipping. Tight Bond II is available everywhere, so I did not include a shipping cost for it.

In this case the cost difference of PMF over fiberglassing is nearly 1/3 the cost. The larger the project the bigger the cost difference would be.

I have use fiberglass and I don't like working with it. Nothing about it is fun to me. PMF just works and it is simple to do. I always tell people, if you can hang wall paper you can PMF. You also don't have to worry about a possible reaction to it.

As far as fiberglass being more waterproof? I doubt it. Here are some pictures of TBII that I had thinned down to 50/50. 50/50 is my go to mix ratio for all my builds.

Now imagine TBII applied to the wood then canvas and then another coat of TBII. It is going to be watertight.

Well, that is my two cents... Carry on.

 

[saywhatthat]

to me if your going with a plywood base better with PMF .If going with a fiberglass shell then plywood is a waste of time and cash. You seem to want the wood stud and ply I say go with poor man covering. If you plan to insulate will cost more than real glass foam. How are you going to store it?
If your going to do pmc do you plan to do a small box first ? I tried PMC it was to hard to me . that why I like the other everything wet is flat
The one thing to look out for with glass on wood is you get a crack you don't see tell all the wood under rots

 

[reaver]

Resin and glass isn't than much more expensive than PMF and is more waterproof.

I did the numbers on PMF over Fiberglassing just to see what the price difference really is. People always say that fiberglassing is just a little bit more than PMF so why not just Fiberglass. Well, there really is a reason it is called PMF.

Here are the numbers using the materials recommended earlier in this post for fiberglassing.

6 Yards 6oz x 60" Fiberglass $46.50
6 Yards 6oz x 50" Fiberglass $42.00
6 qt Kit Non-Blushing Epoxy $114.05
Total Before Shipping Costs and Tax $202.55

Here are the numbers for PMF.

15 Yards 60" 7 oz Cotton Duck $59.85
1 Gal Tight Bond II $26.99
Total Before Shipping Costs and Tax $86.84

I did not add in tax and shipping because that is a variable that might be mitigated by local resources. If you did however have to order in the materials the epoxy resin and fiberglass is 37.04 for shipping. I would suspect that is because it is a chemical. 15 yards of cotton duck cost 7.99 for shipping. Tight Bond II is available everywhere, so I did not include a shipping cost for it.

In this case the cost difference of PMF over fiberglassing is nearly 1/3 the cost. The larger the project the bigger the cost difference would be.

I have use fiberglass and I don't like working with it. Nothing about it is fun to me. PMF just works and it is simple to do. I always tell people, if you can hang wall paper you can PMF. You also don't have to worry about a possible reaction to it.

As far as fiberglass being more waterproof? I doubt it. Here are some pictures of TBII that I had thinned down to 50/50. 50/50 is my go to mix ratio for all my builds.

View attachment 2

View attachment 1



Now imagine TBII applied to the wood then canvas and then another coat of TBII. It is going to be watertight.

Well, that is my two cents... Carry on.

OK George, riddle me this.... Why titebond 2 over titebond 3?

 

[ghcoe]

You can use TBIII if you want. Some people do. I am not familiar with an application method for it and no personal experience with it as well. I think in general it is just more expense with little to no extra benefit for what we use it for.

 

[reaver]

You can use TBIII if you want. Some people do. I am not familiar with an application method for it and no personal experience with it as well. I think in general it is just more expense with little to no extra benefit for what we use it for.

I really want to try pmf. So, here's what I'm gonna do.

The first thing I'm going to build is my kitchen box. I just need it to warm up enough that I can work outside. Once I have the box built, I'll bring it inside, and give pmf a try in the basement where it's going to be much warmer.

I really need to build that second shed and convert the current shed to a workshop...

 

[ghcoe]

I have applied PMF in the 40's, but I recommend above 55.

You can watch how I apply the PMF here.

[youtube]NeR6WVAlenk[/youtube]

 

[reaver]

OK, doing lots of research on the pmf process, this will definitely work. I'm still deciding between tb3 and tb2 glue. Now, my last question about this process...

Should I seal the wood with cpes prior to pmf, or does the glue seal the wood enough so that I doesn't need a few coats of cpes?

I'm planning on using the following canvas:

https://www.canvasetc.com/product/canvas-duck-7oz-72/

 

[ghcoe]

OK, doing lots of research on the pmf process, this will definitely work. I'm still deciding between tb3 and tb2 glue. Now, my last question about this process...

Should I seal the wood with cpes prior to pmf, or does the glue seal the wood enough so that I doesn't need a few coats of cpes?

I'm planning on using the following canvas:

https://www.canvasetc.com/product/canvas-duck-7oz-72/

Not a very uniform weave, but a good price. Since you're going to cover it up with panels anyway should work just fine.

Essentially you are applying a watertight covering over the wood, like an old wood canvas canoe. In fact, the modern wood canvas canoe makers use TBII in their dope now. I don't think you will need to cover the wood with CPES. In fact, it might not play well with TBII. Now when you drill into the wood for your edging you will probably want to put some kind of wood protector in them before you add the screw.

 

[reaver]

Not a very uniform weave, but a good price. Since you're going to cover it up with panels anyway should work just fine.

Essentially you are applying a watertight covering over the wood, like an old wood canvas canoe. In fact, the modern wood canvas canoe makers use TBII in their dope now. I don't think you will need to cover the wood with CPES. In fact, it might not play well with TBII. Now when you drill into the wood for your edging you will probably want to put some kind of wood protector in them before you add the screw.

Cool. All the examples I've seen so far, they haven't coated the wood with cpes. I plan on having all the holes drilled prior to skinning. I may decide to attempt to just paint it instead. I'm unsure as of right now.

But, at least I'm getting a solid plan in place.

 

[reaver]

Picked up my base trailer earlier this week:

Planning on starting working on the kitchen box this weekend, and stripping the trailer down to the bare minimum.

Also planning on starting to build the main trailer in early March.

 

[reaver]

Ok, I think I've finalized the design of the trailer.

Bear with me here, as there's a lot to go over. First off, exterior shots, giving an idea of what it's going to look like when it's all built.

3/4 Passenger (Camp) side view

3/4 Driver Side View

Rear Galley View

Inner Structure

I've decided to change the way I'm doing the inner structure of the walls. I will cut the voids out of a single sheet of 3/4 plywood. This should be stronger than trying to frame it using 1x2. It's a bit more complicated to get everything correct, but if I take my time drawing everything out on the first piece, I can use the router to create an exact copy for the other side.

The inner most layer of wall will be 1/4 in plywood, with the outer layer being 3/8 plywood for a bit extra durability. The voids will be filled with 3/4in foam insulation on the walls, and 1.5 in insulation on the front and roof.

Galley

The galley is the most complicated part of the build. I wanted to maximize storage space, while maintaining easy access. The rear door will also be narrower than the width of the trailer, so I needed to figure out a way to use that space on the sides of the door. Four drawers will live underneath the counter, allowing storage for utensils and pots/pans and other various items. The center space will be taken up by my 100Ah lifepo4 battery, DC-DC charger, and 40A solar charger, with the 2k diesel heater occupying the bottom section. I'll have a false panel that will be screwed in covering those items up, but allowing for easy access in the case I need to get in there.

The red box on the side of the counter top will be my distribution panel. It has a cover, but will allow for easy access in the case of a blown fuse

Interior

The interior has two areas for storage. The first being the main wardrobe cabinet. I designed it so that it had room for 5 front runner flat boxes, with a few small cubbies for things like socks, and small things that we'd like to be able to access.
The black items on the front are as follows. Top is a USB-C powered portable PC monitor with HDMI input. This will be run from a raspberry pi running Kodi for some entertainment when the weather is ultra crappy. Middle is a simarine Pico system display. This will tell me the state of my battery, temperature inside and outside, water levels, and fuel level for the diesel heater. Bottom is the control for the diesel heater.

The above head storage is basically just a shelf that we can put some games on, as well as set up our CPAP machines, and leave them set up.

And here's a few more shots of the full structure of the trailer as it's currently designed.

Now I just need to save for the rear door, and then wait for a friend of mine to get his garage, so we can start building it!!

 

[reaver]

Ok, I've been accumulating parts needed for the build.

Things that I'm currently sitting on, or are in flight.

Simarine Pico battery monitor system is here, and I've been playing around with it. What a cool setup. Once I get a good water tank level sensor, that'll be amazing.

Rear galley door was delivered to my buddies house the other day.

Main cabin doors are sitting in my basement

Vent fan was delivered yesterday. I opted to buy a fan with integrated lights for simplicity. I'm going to see about adding a dimmer (which I've ordered) to control the light

All the primary components for the electrical have been ordered. I'm going to need to order more 16AWG wire, but how much will depend on a number of factors, so I'm holding off on that. Bus bars, anderson connectors to allow for removal/replacement of chargers, progressive dynamics power distribution panel, and 4awg battery cables are all inbound.

I will also need to get my reading lights, exterior lights, and a couple of weatherproof aviation plugs. I'll be using a 5 pin on the drivers side. This will allow me to put the Diesel heater in a box on the side of the trailer (similar to my kitchen box, while still having the thermostat and controls inside the trailer. One cable hooked up when we get to camp, and we have heat. 2 pin on the passenger side will run power to the kitchen box, and power a light, a couple of USB ports. Another will run power to the RTT.

Tenative build start date is 3/23.

Starting with the floor, wall skeleton, and the spars.

I'm getting excited!!

 

[Tony Latham]

Starting with the floor, wall skeleton, and the spars.

I think you should consider installing the spars on the skeleton, and not inset into it. It will allow you to set the headliner on before the spars and will give a perfect joint between the inner wall and headliner. It's called building inside out.

Here you can see how the headliner is set first:

https://youtu.be/rIUUaEKe4mw?si=nGq90mHlNqKY__V-


Note the tight joint:

When you go this route, save the 2" cut offs from the skeleton and use it for blocking between the spars to gain the desired strength that you have in your current design.

It's a thought.

Tony

 

[reaver]

Starting with the floor, wall skeleton, and the spars.

I think you should consider installing the spars on the skeleton, and not inset into it. It will allow you to set the headliner on before the spars and will give a perfect joint between the inner wall and headliner. It's called building inside out.

Here you can see how the headliner is set first:

https://youtu.be/rIUUaEKe4mw?si=nGq90mHlNqKY__V-


Note the tight joint:

When you go this route, save the 2" cut offs from the skeleton and use it for blocking between the spars to gain the desired strength that you have in your current design.

It's a thought.

Tony

That's not a bad idea. I'm not sure why I never thought of that. I realize that most folks build from the inside out. My plan was to do the opposite, as to not occupy my friends garage for any longer than necessary. I'm less concerned about the seam on the inside roof, as I planned to run a clean bead of caulking, and eventually install a piece of trim that's routed out for an led strip for additional mood lighting.

But if I just pre-run the wires in the roof, it likely won't be an issue.

 

[Tony Latham]

But if I just pre-run the wires in the roof, it likely won't be an issue.

This is how I run my wires:

It requires cutting a groove in the spars.

As far as building inside out, it also makes for a much quicker building process since adding the headliner first––and then the spars––is easy-peasy.

But you're on your way, so enjoy.

Tony