Building a dedicated shore diving trailer

[CanadaDan]

If this is just to transport gear from your primary residence to a cabin/cottage/beach house then ignore this but I would add some roll up shades if possible. Don/Doff gear in the shade versus heat of the sun. Any chance for an offroad shower ( ) or similar?

Thankfully most diving will be at my cottage (full plumbing etc) or at a provincial park that has a campground as well as a dedicated scuba area. Full bathrooms, showers and change rooms provided. If we venture further afield down the road then I’ll look at a on demand propane shower with a 12v pump.

 

[CanadaDan]

I don't know anything about trailers, but I assume there's some fore and aft weight balance requirements. Putting all the heavy stuff right by the door is obviously more convenient, but will it balance correctly?

Should be near perfect. My layout puts most of the weight centred JUST ahead of the axel so the tongue weight won’t be too heavy.

Lead and tanks are the main weight and they will be on the floor balanced side to side and over the axel.

 

[CanadaDan]

I’ll also be adding levelling jacks at the back corners so when it’s unhooked from the tow vehicle I can still step into the back.

 

[broncobowsher]

First thing I saw in the layout was "this is horrible".
I setup trailers for work. SAE J2807. What the auto makers usually agree to when rating tow capacity, that has been a part of my life for over a decade. Actually have a co-worker who is on the board for that standard. Know it too well. I have set up hundreds of trailers. Some wrong, some very wrong, but I have learned a lot and have it down really good now. Last trailer I setup was 3 tons and completely safe and comfortable towing at 95 MPH (150 Kanadians Per Hour).

Your loading plan is horrible. Too much weight aft of the trailer axle. Everyone harps on the 10-15% tongue weight like it is the magic fix for setting up a trailer. I've done enough I can set up trailers to spec that tow great, or tow like crap. And I can set a trailer completely out of spec and still make it tow great. It comes down to the mass behind the axle. Moments of inertia. The back of a trailer is the roughest riding place on a trailer, things will get tossed there more than anywhere else. Heavy weight back there will toss the back of the trailer around. Even if the front is counterbalanced. Weight at the back of the trailer is as bad as it can get. Only gets worse if you add height. Next worse is the weights at the ends of the trailer so it is balanced,

Get that mass just in front of the axle. Just in front of it is perfect. Not that you are looking at tandem axle trailers, but if you center the mass over the forward axle on a tandem axle cargo trailer you are 98% chance of it towing as good as possible. For a single axle, center the mass over the crossmember that connect the front spring hangers. Or the forward edge of the tire is another reference point. If need be go a little forward.

The light stuff that can take some bouncing, put that in the back behind the axle. Probably the suits will be best. If running hangers be sure to get really heavy duty ones. Stuff you want a gentle ride (computers, masks, regs) should go in the front of the trailer.

 

[wheeledgoat]

I have zero experience with trailers, but I subscribe to a "round up" theory for most things like this (redesigned my kitchen, building a shed, basement shelving, etc...). Whenever I find myself asking if I should go bigger, the answer is YES. The question isn't "is it too small?" - the right size is when I start wondering if it's too big. I've never been sorry.

 

[CanadaDan]

Fair enough bronco... shifting the weight forward is no big deal as it’s just where the lead boxes and tanks get bolted to the floor/wall. It’s why there’s nothing else on the floor along the walls in the plan. Easy to make adjustments as needed.

Thanks for the tip about centring the weight on the front spring shackle/crossmember as opposed to the axle.

For the record the tow vehicle is factory tow equipped with self-leveling rear shocks and I’ve towed ski boats, other trailers much heavier than this rig with it. Fully loaded the trailer will be well under its own load rating and equally below the weight the vehicle is rated for.

 

[tbone1004]

the solidworks file I showed you actually had all of the masses entered for the tanks and the trailer and was optimized for 15% tongue weight. The trailer I had was single axle and it was set really far back so there wasn't a whole lot behind the axle in the grand scheme of things. The issue I had when setting it was actually the tongue weight limitations since the tongue wasn't long enough for a WD hitch I couldn't go over 15% without going over the hitch weight and payload capacities.

 

[JBFG]

You should contact the team in Wainwright, Ab. They have a trailer as well that they use. I dove 2 years with this excellent team and their trailer is awesome!
They could give you some good tips as well.
ALBERTA ADVENTURE DIVERS

 

[Barnaby'sDad]

Cool project. Good luck putting it together when the time comes.

A couple things:

x2 on going with no colorful graphic on the outside of the trailer. I’d want it to look as plain as possible and not stand out. Ex. Plain white or black finish. Don’t advertise that you’re hauling around thousands in gear.

x2 on the size concern, as well. Not saying that you won’t be able to make it work, but that 4x6 is on the small side and allows you no room for growth. Ex. Want to haul extra stuff along, have a dual purpose trip, etc. Just my two cents.

 

[broncobowsher]

I'll add that 4x6 is really small. Add an easy up shade and a few chairs and it will be really packed. No room for growth at all. When you show up to dive the first thing you will have to do is empty most of the trailer just to reach whatever is in front. 5x8 is roughly the floor space of a full size truck bed. I know it costs more, but cheaper then having to buy it later. You would have a hard time getting any good money out of a used 4x6. Too small for most people.

Take some tape and mark a 4x6 space on the ground and mock load your gear. Don't go in from the sides, there are walls there. Only give yourself that one opening to get everything in and out. Do that before you drop a dime on that size trailer. Having to step through gear, take gear out to reach around. Easy if there is no side walls. And stay hunched over, they have a low roof height as well.