Trailer in Design stage

[RJ Howell]

Looks like in this group several have built your own trailers! This looks the the place to ask some questions and learn!

I'm going to build my next trailer. I know my wants and have started to design. Currently I'm using Sketch-up on my Mac for this purpose.
What programs do you folks use?

I require to be able to stand up it in, yet haul low-profile. Yep, must have a pop-top!
When I saw Wesley Harville's Foxtail Camper.. Ya, that's the Pop-top!
Foxtail Camper

I have learned from 20K plus miles Boondocking over the last year, that we need a inside shower. Working with the wet-bath we now have, I see it is completely possible.
I just need to re-design it to be more efficient/practical. I have a concept of a low wall and a hinged cover to be able to utilize counter space and flip it up to use the toilet/shower.
This is one of those designs I'm finding hard to do in Sketch-up.

A inside kitchen (as well as a outside) is also a must to this build.

Well, I could go on for quite a while longer, but for now.. Consider this my introduction to ya all and an idea of where I'm headed.

 

[shade]

Welcome to ExPo! ?

You may have already considered all this, but since you're in the design phase, I'll throw a couple of thoughts out.

I'm not a trailer builder, but one thing that I've seen get people into trouble with many projects is not keeping a close eye on weight. It's easy to let it get away from you, and before you know it, your lightweight easy towing camper is maxing out the suspension & the weight distribution is off.

Ventilation will be very important for an inside shower, and for an indoor cooking area. The humidity coming from those two sources can be a challenge to control, and will quickly saturate the entire interior. Even if it makes it more cramped, I'd consider making the shower compartment as much of a self-contained, sealed capsule as possible to limit air flow with the rest of the camper. An inside kitchen may be tougher to manage that kind of isolation, but if you design to have a draft pulling air directly outside from the cooking area through a nearby vent, it may help minimize cooking humidity and odor creeping into other areas.

 

[RJ Howell]

Welcome to ExPo! ?

You may have already considered all this, but since you're in the design phase, I'll throw a couple of thoughts out.

I'm not a trailer builder, but one thing that I've seen get people into trouble with many projects is not keeping a close eye on weight. It's easy to let it get away from you, and before you know it, your lightweight easy towing camper is maxing out the suspension & the weight distribution is off.

Ventilation will be very important for an inside shower, and for an indoor cooking area. The humidity coming from those two sources can be a challenge to control, and will quickly saturate the entire interior. Even if it makes it more cramped, I'd consider making the shower compartment as much of a self-contained, sealed capsule as possible to limit air flow with the rest of the camper. An inside kitchen may be tougher to manage that kind of isolation, but if you design to have a draft pulling air directly outside from the cooking area through a nearby vent, it may help minimize cooking humidity and odor creeping into other areas.

Thank you for the input!
I visited a manufacture of a unique Pop-top camper last year. Though there unit was far too expensive and also too weak for what we wish to do, I gathered some good ideas on moisture control.
I'm going through all types of structure styles/builds/materials and checking weight. I am hoping someone hear has an option (US/Canada based hopefully) for structural/composite panels.

 

[RJ Howell]

A couple of screen shots of my design. Outside is roughed, component drawing is tighter (though still not much).
Drawn in travel mode with topper down.

 

[shade]

Do you already have a base trailer selected, or are you building that yourself?

 

[RJ Howell]

Do you already have a base trailer selected, or are you building that yourself?

So far, building that as well. A friend has a large aluminum boat trailer he wants gone. Might be a good material source..
From what I have seen in most builds, I don't see in pre-builts..

 

[Louisd75]

A couple of screen shots of my design. Outside is roughed, component drawing is tighter (though still not much).View attachment 525462View attachment 525463
Drawn in travel mode with topper down.

My seat of the pants reaction is that your axle looks really far forward. Keep in mind that too much weight aft will unweight the tongue and can lead to sway.

 

[RJ Howell]

My seat of the pants reaction is that your axle looks really far forward. Keep in mind that too much weight aft will unweight the tongue and can lead to sway.

That's one of my 'biggest' questions to you folks that have built. Determining the placement of the axle. I'm certain it has to do completely on weight placement, yet any 'rules-of-thumb' to go by?
The only one 'I' know of is 10-15% of the trailer weight should be on the tongue.

 

[DaveInDenver]

The rule of thumb I've heard repeated often is to locate it 60% of the distance from the front of the cargo bed or box.

But the actual ideal location of the axle depends on the center of mass of the trailer. You want 10% to 15% of the total weight on the tongue so you have to calculate base weight and all the cargo you plan to carry and locate the axle based on that. You'll have to estimate as best you can.

Too much weight on the tongue makes the trailer stable but unloads the towing vehicle's steering. Too little makes the trailer unstable at speed on the Interstate. That's the reason for the sway an earlier poster mentioned, more weight behind the axle than in front.

I suppose the error to make is to be just slightly less than ideal tongue weight and be able to trim it with a tool box on the tongue. But then how you load it is always critical.

OTOH if you're over weight on the tongue (axle further back than ideal) then the trailer will always be stable no matter how you load it and you can adjust using air bags or stronger springs on the truck, if you exceed the maximum tongue weight.

So I'd follow the 60% rule if you can't trust your analysis because it's likely that will be beyond the margin of error and as long as you don't exceed the max tongue weight you'll be safe.

 

[RJ Howell]

The rule of thumb I've heard repeated often is to locate it 60% of the distance from the front of the cargo bed or box.

But the actual ideal location of the axle depends on the center of mass of the trailer. You want 10% to 15% of the total weight on the tongue so you have to calculate base weight and all the cargo you plan to carry and locate the axle based on that. You'll have to estimate as best you can.

Too much weight on the tongue makes the trailer stable but unloads the towing vehicle's steering. Too little makes the trailer unstable at speed on the Interstate. That's the reason for the sway an earlier poster mentioned, more weight behind the axle than in front.

I suppose the error to make is to be just slightly less than ideal tongue weight and be able to trim it with a tool box on the tongue. But then how you load it is always critical.

OTOH if you're over weight on the tongue (axle further back than ideal) then the trailer will always be stable no matter how you load it and you can adjust using air bags or stronger springs on the truck, if you exceed the maximum tongue weight.

So I'd follow the 60% rule if you can't trust your analysis because it's likely that will be beyond the margin of error and as long as you don't exceed the max tongue weight you'll be safe.

Thank you! The 60% rule fits what I see on my current trailer.

 

[RJ Howell]

My seat of the pants reaction is that your axle looks really far forward. Keep in mind that too much weight aft will unweight the tongue and can lead to sway.

I just went through your build and see you skinned with aluminum. Getting way ahead of myself (sort of, still working out weight of materials), yet will ask. You chose aluminum over fiberglassing the plywood. Curious why?

 

[billiebob]

Looks like in this group several have built your own trailers! This looks the the place to ask some questions and learn!

I'm going to build my next trailer. I know my wants and have started to design. Currently I'm using Sketch-up on my Mac for this purpose.
What programs do you folks use?

I require to be able to stand up it in, yet haul low-profile. Yep, must have a pop-top!
When I saw Wesley Harville's Foxtail Camper.. Ya, that's the Pop-top!
Foxtail Camper

I have learned from 20K plus miles Boondocking over the last year, that we need a inside shower. Working with the wet-bath we now have, I see it is completely possible.
I just need to re-design it to be more efficient/practical. I have a concept of a low wall and a hinged cover to be able to utilize counter space and flip it up to use the toilet/shower.
This is one of those designs I'm finding hard to do in Sketch-up.

A inside kitchen (as well as a outside) is also a must to this build.

Well, I could go on for quite a while longer, but for now.. Consider this my introduction to ya all and an idea of where I'm headed.

Guy needs to find a way to license the FoxTail Camper design and get it produced.

 

[The Artisan]

Looks like in this group several have built your own trailers! This looks the the place to ask some questions and learn!

I'm going to build my next trailer. I know my wants and have started to design. Currently I'm using Sketch-up on my Mac for this purpose.
What programs do you folks use?

I require to be able to stand up it in, yet haul low-profile. Yep, must have a pop-top!
When I saw Wesley Harville's Foxtail Camper.. Ya, that's the Pop-top!
Foxtail Camper

I have learned from 20K plus miles Boondocking over the last year, that we need a inside shower. Working with the wet-bath we now have, I see it is completely possible.
I just need to re-design it to be more efficient/practical. I have a concept of a low wall and a hinged cover to be able to utilize counter space and flip it up to use the toilet/shower.
This is one of those designs I'm finding hard to do in Sketch-up.

A inside kitchen (as well as a outside) is also a must to this build.

Well, I could go on for quite a while longer, but for now.. Consider this my introduction to ya all and an idea of where I'm headed.

Use some of my ideas in my proto layout.
I have since changed my design to rain head in the roof.
Kevin

 

[The Artisan]

Guy needs to find a way to license the FoxTail Camper design and get it produced.

With my frp panel, exo cage kit and my hardsided poptopper, that can easily be done. You can do a full size door when fully extended. Have a offroad trailer built and my diy pod can be attached. Finish interior as you see fit.
Kevin

 

[shade]

Guy needs to find a way to license the FoxTail Camper design and get it produced.

Maybe, but the pop-up structure needs to be refined. Even from the video, there's too much time spent with fiddly bits. From what I've seen of @The Artisan's design, it's a simpler, quicker process.