Modify or Build from Scratch? How do you like this idea?

[TheNatural]

I would recommend building from scratch. I have a few ideas not already mentioned. If getting anywhere close to 3500lbs and using off road I would move to a 5k axle particularly if you want to use oversized tires. It may not look as cool but you could get your desired track width and make the deck wider in front and/or behind the tire, there is no actual rule that the bed has to be inside the wheelwells. For the snowmobile you could build a couple of trailer hitch receivers into the rear of the trailer and slide an extension into them to lengthen the bed when using the snowmobile. Think it as one of those hitch haulers but with 2 or 3 hitches. Around here tube frames tend to rust from the inside out. I would recommend using C channel and angle iron and minimizing tubing. Tubing is also a lot more expensive. I am a leaf spring guy, and for a trailer used off road would recommend longer than trailer leaf springs. Look for something off a vehicle that has about a 3000 to 3500 GAWR . Something like your Tacoma springs from craigslist or junkyard would probably be ideal

Last night I spent some time looking into independent suspension options.. Timbren offers their torsion axles in a 3500 heavy duty configuration that caught my eye. They are sprung for a 3500lb load but use 6000lb hubs/spindles. It seemed like a good way to get strong components and a good ride at the same time with the least amount of effort on my part, but I'll have to seek out some more reviews and such before I commit. They seem a bit more expensive which is always a consideration too. If I end up going leaf springs I'll probably use some Chevy 63's. Either junkyard springs or a cheaper aftermarket lift pack and just pull leafs out one at a time until the ride quality is good.

I've modified my plan in my head a bit to include the deck being wider in front and perhaps behind the tires. That's the only way to accommodate the horse shoe "expo box" set up. Both the snowmobile and the atv are about 36" center to center (ski stance or wheel), so about or a little over 43" outside to outside. A 45" wide deck between the wheels gives me an axle WMS to WMS of 61" with the heavy duty Timbrens. Then I'll build the ~1' wide side boxes on a wider section of frame in front of the wheels to end up with something about the same track width and overall width as my tow vehicle. Perhaps some rollover fenders and a bit of extra flat deck width in front of and behind the axle just in case I end up with a wider ATV at some point in the future.

I really like the extension idea for the snowmobile in winter. It makes a lot of sense given the places I go - much more truck based exploring in the summer where the shorter trailer and better departure angle will be nice, but winter is mostly pretty tame terrain because the good stuff is under too much snow.

For me the consideration for tandem axles is less about weight and more about safety. The two primary areas are with blowouts on the highway and improved departure angles. For the first, if you will be doing a lot of highway miles going to your destination then a tandem would be valuable. A blowout on a single axle can be catastrophic. For departure angles it would be beneficial if you are doing a lot of off-roading with significant drops. For these two reasons I bought a tandem. Fortunately I haven't had a blowout to worry about but have used the improved clearance many times.

I don't really have concerns about blowouts... maybe that's just hubris, but I haven't had issues with them before and I plan on using quality rubber. The better angles would be quite nice though. I'm surprised I hadn't thought of that benefit - thanks! I still don't think I'll go dual axle due to cost and rotational mass, but I might give it a little more thought.

 

[ITTOG]

When was the last time you had a blowout on your rig?

I run 6 ply LT radial tires on my teardrops and they don't pop.

T

Luckily no but I have to go a long way on the highway to get to a place worth visiting. I don't care how many ply's you use. Some states roads are so bad even a ten ply won't help you. Not to mention manufacturing defects do occur.

Sent from my Pixel 3a XL using Tapatalk

 

[Teardropper]

Some states roads are so bad even a ten ply won't help you. Not to mention manufacturing defects do occur.

Nothing is worse the backroads of Montana, Idaho, and Utah.

T

 

[ITTOG]

Everyone has different experiences. I have been driving for a little over 30 years and have had one flat. My son has been driving for a little over one year and has had three, two being blowouts. One blew out with 8/32 tread. The new tire we replaced it with blew out with less than 1,000 miles on it. You just never know.

 

[billiebob]

Nobody has brought it up yet, but I'll put the axle in a good spot to get appropriate tongue weight when loaded up.

I had a Caraven 5x8, made it a 5x11 to better fit my touring Arctic Cat. I must admit modifying a trailer is a blast.
No pics with the sled but here is a pic with the "cargo" body used to bring my tools from Yellowknife to Nakusp 12 years ago.
A wee bit heavy on the tongue, only 1500# overloaded but it did the job, 1700km in 2 days. I used 2x3 tube to drop the tongue and 2x4 tube to lift the trailer.

There will always be nay sayers, do what feels right. Try to keep it legal.


Once in BC and not sledding, that trailer went back to 5x8


I went to 30x9.50 tires from the 12" factory rubber and kept it all under the trailer. It worked but the track vs height was a bit skinny.

 

[TheNatural]

You tire argument guys... can we please agree that blowouts can happen but are not very common, and move on? Everyone has different risk tolerances and priorities so something that's not worth worrying about to one person will be something that needs to be guarded against for someone else.

I had a Caraven 5x8, made it a 5x11 to better fit my touring Arctic Cat. I must admit modifying a trailer is a blast.
No pics with the sled but here is a pic with the "cargo" body used to bring my tools from Yellowknife to Nakusp 12 years ago.
A wee bit heavy on the tongue, only 1500# overloaded but it did the job, 1700km in 2 days. I used 2x3 tube to drop the tongue and 2x4 tube to lift the trailer.

There will always be nay sayers, do what feels right. Try to keep it legal.
View attachment 560350

Once in BC and not sledding, that trailer went back to 5x8
View attachment 560351

I went to 30x9.50 tires from the 12" factory rubber and kept it all under the trailer. It worked but the track vs height was a bit skinny.

That's quite useful. Switching the current trailer to wheels under the deck would get me the track width while avoid needing to alter the frame dimensions at all. For me, though, I don't think it's wise. I'd like to run 35's to match tow vehicle and I'm worried that would put the trailer too high; especially while making the track width narrower at the same time. Yours looks decently well balanced, but another few inches higher and with a RTT up high I'd be very worried about center of gravity being too high and the trailer flopping over everywhere.

 

[TheNatural]

A little bit of preliminary design tonight. No proper drawings to show yet (still in the back of cocktail napkin stage), but I figure the weight of the first design iteration to be about 767lbs for the rolling chassis and plywood deck. About 400lbs in steel, the rest is wheels, suspension, and a plywood deck for the 7' long ATV flat deck section. The frame is designed for a wraparound enclosed storage area for the kitchen stuff like we've been talking about, but I haven't drawn it up or calc'd a weight yet. I should be able to keep it under 1000lbs once I add the storage boxes and water tank, plumbing, etc... all empty and dry of course. I've added two reinforced 2.5"x2.5"x0.25" tubes in the rear to allow for a deck extension to be added in snowmobile season which will also add a few pounds.

For anyone that built their own expo trailer or bought one and paid attention to weight.. does 1000lbs dry seem about right? Trailer is about the size of a 4x9' flat deck.

 

[NatersXJ6]

For your extension socket tubes I highly recommend buying pre-made receiver tubes. They already have the internal weld bead flattened and are cross drilled for pins. Generally available in lengths from 6-48”

I think 1000 lbs is manageable. I’m pretty sure my commercial 7x16 car hauler was only 1500 though. You could probably get a bit lighter without much fear.

You might rethink the plywood deck? Most trailers I’ve seen are 2x6 plank decks. More strength, handles weather much better, easily repaired or replaced, and typically lighter (especially against pressure treated plywood)

 

[TheNatural]

For your extension socket tubes I highly recommend buying pre-made receiver tubes. They already have the internal weld bead flattened and are cross drilled for pins. Generally available in lengths from 6-48”

I think 1000 lbs is manageable. I’m pretty sure my commercial 7x16 car hauler was only 1500 though. You could probably get a bit lighter without much fear.

You might rethink the plywood deck? Most trailers I’ve seen are 2x6 plank decks. More strength, handles weather much better, easily repaired or replaced, and typically lighter (especially against pressure treated plywood)

Wasn't aware of premade receiver tubes, but that's a game changer! I'm in!

I suppose the 2x6 deck would be a good idea. That's what's on my current flat deck trailer and it does just fine. It would actually be 26lbs heavier than the 50lbs I threw in for plywood if the numbers I found are correct.... But my plywood number was based on whatever kind of 3/4" ply popped up first when I was googling for a weight, so it is the most prone to error of anything I've added up.

I don't know if I want to go any lighter on the frame. If I drop down one size in channel it would only save about 38lbs and have a much worse Sx, Ix, etc. Maybe I could use the thinner stuff for portions with less stress, but I was trying to keep to just 2 steel cross sections for the main frame (receiver tubes and C3x4.1) to simplify the bill of materials. I could save a bit by not tying the receiver tubes in quite as far as they're pretty heavy... I'll consider it when I'm doing a more detailed design.

The real opportunity for weight savings is in the wheels at about 100lbs each, but I want them to match the tow vehicle so I'm stuck with it. The timbren 3500HD axle less suspension is listed at about 150lbs and I might be able to save up to 60lbs by going with something else, but I'm not sure if I want to go lighter duty on that either.

 

[NatersXJ6]

If you are already at C3 x 4.1 you are as light as I would be going. Sounds like fun. Good luck!

 

[CampStewart]

I always buy 4ft pieces of receiver tube from E trailer. Free shipping with I think 100 dollar order. That is the best price I have found

 

[TheNatural]

I went from a cocktail napkin sketch to a sketchup sketch of the frame... the wheels are there for reference and are 35x12.5 (axle placement is a just a guess, will be based on actual center of mass calculations later on). Wider looking parts are 2.5" receiver tube and the rest is C3x4.1 channel. But I went back and had a look at the axle width number I was using because it didn't look quite right. The internet told me '95-current Tacoma axles were 60.75" wide... but that must be really old information because my 2012 is about 66" WMS to WMS. So my design is too narrow and needs to be widened by 6", but should look something sort of like this draft (which isn't dimensioned anyway so you probably wont even notice the difference!):

 

[CampStewart]

I wouldn't design a frame with the gusseting on the tongue. If you are building it to put on a A frame box just build your trailer bigger to have a full length box. If you feel you need to gusset the receiver tubing use a larger diameter tube and neck it down the last foot with the receiver tubing. I want to be able to turn 90 degrees to the trailer and as far as I am concerned an A frame like that jis just a waste of space or a styling exercise. I would carry the rear receiver tubes forward to at least the next stringer but use thinner wall tubing to save weight.

 

[Teardropper]

I like being able to remove my hitch once we're in camp.

T

 

[TheNatural]

I wouldn't design a frame with the gusseting on the tongue. If you are building it to put on a A frame box just build your trailer bigger to have a full length box. If you feel you need to gusset the receiver tubing use a larger diameter tube and neck it down the last foot with the receiver tubing. I want to be able to turn 90 degrees to the trailer and as far as I am concerned an A frame like that jis just a waste of space or a styling exercise. I would carry the rear receiver tubes forward to at least the next stringer but use thinner wall tubing to save weight.

Being able to get a full 90 degrees to the trailer is a good point. I can probably come up with something that involves a bigger single tube and still transitions to the frame rails without the sort of abrupt change in rigidity that leads to cracking. I'll definitely have a closer look at it.

I like being able to remove my hitch once we're in camp.

T

That's kind of neat too. I usually put a lock on a trailer when I'm not hooked up to it, but I guess I wont be able to use the same kind of locks with a lock'n'roll (or other articulating hitch yet to be decided).