Gas Spring Ordeal

I went back and forth with http://www.internationalgassprings.com/ about which size to order. After I finally settled on a size, they sent me this email:

"I have not been able to get back to you as our normal business has picked up. IGS is a wholesale operation which typically ships high volumes of springs at a time. We are not set up for small quantity orders. I had some spare time when you contacted me the first time and offerred some help but at this point cannot spend any more time on it. Your best bet is to buy the springs from Mcmaster-carr who will offer a similar size http://www.mcmaster.com/. "

So, save yourself the hassel and go to McMaster to start with. Their gas spring page here.

Ball ends and mounting brackets here.

I just completed my order. Based on the info from IGS, I picked the 9416K22 gas spring. It basically has the same specs as the one IGS recommended: 28" extended length, 12" stroke, 25o lbs force. Since its an M8 rod end instead of M10, its one third the cost, only $18.77 each! Hopefully it is not too wimpy to stand up to offroad use. Guess we'll see. I ordered some extra ball brackets to allow me to use multiple mounting positions. This should allow one position for lid empty, and one for lid rack loaded up. I plan to start with the mounting positions IGS gave me and see how they work.

Hitch Extension/Riser

When I did the spring over lift on the trailer it really made it tall. The lunette is about 30" off the ground. When I get my Jeep Unlimited (4-door) with a 4" lift and 37" tires, it should sit level. For now, with my 2.5" lift and 33" tires, the trailer has to really lean down. I've seen the adjustable ball hitches that all those huge lifted pickup trucks have, so I thought why not make something like that for the pintle. I started with a 12" receiver hitch tube from harbor freight which was on sale for $6.99 and grinded the paint off and cut it down to size.

Using 2" square tube I measured out enough length to clear the spare tire.

Then I welded it all together and added a angled piece for extra strength.

It looks kinda funky, we'll see if I end up using it. Once the trailer is painted I'll do some test runs to see if I like pulling the trailer with or without the hitch extension.

Lid Bondo

This weekend I filled in some of the small pinholes and pitted surfaces left by my poor welding skills on the top of the lid. The two sheets of 22 gauge metal were pretty tough to get a nice welded seam. So, rather than battling with spot welding hundreds of spots, I decided to fill it in with body filler.

Gas Springs

As I mentioned in a previous post, I found this company International Gas Springs on the internet. You fax them in the specifics of your project and they plug it into their computer program to figure out the correct strength, stroke, and mounting position of the gas springs for your lid. I'm not sure yet how I'll mount the springs since they have only a 1/2" long threaded stud on the end of the metal ball joints. They are pricey too! $215 with shipping. So, don't forget to budget that into your project.

Bedliner

Today it was warm and sunny enough to tackle bedlining the inside of the trailer tub. I picked up a duplicolor bedliner kit at Advance Auto Parts on sale for $46. I wiped down the inside with a scuff pad and solvent based cleaner first. Then I put two coats of goop on with the special brush.

Lid Mounted Trail Rack

After skinning the lid, I added a trail rack using 3/4" square tube. I went with 3/4" to reduce weight and make it easier to strap things to since most straps have a hook on the end that won't fit over 1"square tube. This is just extra storage in case I run out of room inside the tub on an extended trip. I purchased some "Clutch" fork mounts from Rocky Mounts to hold a couple bikes and bolt those to the lid.

Tail Lights

I've broken my TJ's tail lights on the trail before, and dented in the back of jeep quarter panel hitting them as well. I didn't think exposed tail lights would last long on this trailer, so I went for something flush mounted. The drawback is I am comprimising my water tight seal of the floating tub concept. However, the rubber bushing on the light does ok, and I'll add some silcone to seal it when everything's done. The lights are $15 each from Harbor Freight.

As seen from the inside picture, the light is pretty well tucked above the angled part of the tub, so I don't think it will interfere with packing gear. The light does have a small rectangular part that sticks out the back.

Cutting in the Lights

I ordered a nice hole saw set on ebay which made quick work of cutting the perfectly round holes for my LED marker lights. I wasn't too concerned about weakening the frame since mine has 1/4" thick plate of steel welded over the whole thing which increases its rigidity. After the hole was cut I popped in the light for a test fit. Works great.

Skinning the Lid

Above is a photo of the lid after I welded 22 gauge flat plate steel to the frame. This was a HUGE pain. I don't know if my welding skills are that bad (probably) or if I am missing a more obvious way to attach it and make a water tight seal.... The welder was on its lowest setting, but not burning holes in the thin metal was near impossible, as was getting a nice bead. Anyway, I finally finished after draining an entire 10lb tank of gas and then I grinded down my bumpy mess. This has left a pretty rounded edge, but I think its good enough. Here's a close up of some edges...

Here's a view of the underside. I tacked the skin to the frame on every cross member every 4 inches or so. I've heard drumming can be a problem on the highway, so hopefully not having more than 2.5ft x 2ft spans will keep noise to a minimum.

Unfortunately, the steel yard couldn't provide a single sheet big enough for the top. So, I had to use two pieces and weld it together.

Working Lid and Road Test

Here's a look at the lid in operation. I found a company called International Gas Springs who build custom struts. You fill out a worksheet with dimensions and desired operation and they make the size and strength you need to open the lid, keep it open, and close it easily. We'll see how that goes, hope they aren't too expensive. Here is another option at McMaster Carr

I took the trailer out for a highway test yesterday since it was warm and dry out. I got up to 70mph and there was no signs of swerving, fishtailing, or tracking problems. I was concerned the spare tire might add unbalanced load to the tail of the trailer. So far so good.

Lid Frame Finished

Here's a look at the finished lid frame. All that's left to do is order 22 gauge plate steel cut to size and weld it onto the frame to make the skin. Its really coming along well!

Electrical Box

Today I welded on a lockable latch. But to keep the lid from rattling when on the trail, I welded a rubber strap to the lid, and stretched it over a L-shaped knob I welded onto the front of the box. Then I used caulk to seal all of the inside joints in the box to help keep it water tight.

License Plate Mount

The back end of the trailer is almost entirely taken up by the spare tire and tail lights. I didn't want to mount the plate hanging off the bottom of the frame since it would likely be ripped off four wheeling. So, I fabricated a mounting bracket that is welded to the spare tire mounting plate. Its small enough to allow the hub-hole in the wheel to slip over it and onto the studs.

Lid Handle

I found a stainless steel boat cleat which normally is used to tie off ropes for a good price at Harbor Freight tools. I thought it would make a nice sturdy handle. So, I welded in some veriticle supports spaced to match the bolt holes in the cleat.

Hinges & Latches

I bought some heavy duty hinges at Home Depot and welded the pin in place to prevent someone from breaking by pulling the pins out. I decided to bolt the hinges to aid in replacement if they are ever damaged, and to allow the lid to be removed if I need to use the trailer to haul something large with the lid off. The hinge bolts to the 1.5" square tube that I welded below the tub's lip.

It took quite a bit of searching to find the right type of latches on the internet. I got them at Nielsen Sessions. They are smaller than I was thinking, but they will do the job. I wanted them to be stainless steel, lockable, adjustable, and a draw-latch. Making them adjustable ensures a tight fit so you don't have to drill your mounting holes perfectly. Plus, once I add a weather strip around the lid I'll have to re-adjust the latches to make them work. The bottom of the latches bolt to the 1.5" square tube I welded under the tub lip on the driver's side of the trailer.




UPDATE: I had to reverse the latches putting the catch on the top (lid) instead of the tub. When you tried to close the lid, there were three latches dangling which hit the lip of the tub and caused it not to close all the way. With three latches you don't have enough hands to simultaneously pull them out from the tub to allow it to seat properly. Flipping them around keeps the body of the latch on the tub rather than the lid, so when they dangle, they don't get in the way of the lid closing.

Hi Lift Jack

I added some vertical supports using 1" square tube in the box lid spaced to accommodate the Hi Lift 4x4 mounting brackets. The jack is on the hinged side of the lid, which reduces the dead weight you have to lift when you open the top. Once I skin the lid, I'll redrill the holes to remount the brackets.

Fire Extinguisher

Today I added something I hope I will never use. The fire extinguisher seems to fit nicely up front with the fuel cans. Its a tall commercial type cylinder so this was about the only place I could find to mount it. It sits on the angle bracket that butts up against the tub. Then I just added 4 eye bolts and used some old bike rack rubber straps along with some carribeaners. It is held solidly in place, but is quickly accessible.

Electrical Box - Tounge Storage Bin

Since I decided to mount the AT fuel can holders up front, that didn't leave much room for the store bought plastic truck box that I planned to mount to the triangular tounge space. I used some tape to mark off the approximate limits of where I could mount gear before it would interfere with sharp turns on the trail. The space I was left was about 11 x 18 footprint which is enough to house the battery unit.

With 1/16" thick plate steel I had in the shop, I used a circular saw and metal blade to carefully cut out the sides, top and bottom.

In the next photo you can see the box taking shape and how the battery unit fits nicely inside. On the driver's side of the box, I mounted two electrical junction boxes. One will house a weather-proof outlet which will be wired to the outlet in the battery. The second is a weather proof light switch which will operate the LED lights inside the lid.

Here's a look at the box mostly finished sitting in place. I made the same height as the AT fuel can holders.

The last picture here is of the mostly finished box with the lid in place. I welded hinges on. The large gap in the back of the lid is unimportant since I welded a piece of angle iron underneath to form a tight seal. Later I'll be adding automotive weatherstrip.

Spare Tire Mount

After various design iterations I decided to mount the spare tire on the back of the trailer, similar to a jeep wrangler. Due to the weight of the 33" tire, I decided against a fold-down tailgate since my wife would be unable to close it. The other draw-back to a tailgate would be sacrificing the "tub" concept of the original military trailer which allows the trailer to float when doing deep river crossings. My fabrication skills are not precise enough to make a water tight tailgate. The first step in creating the tire mount was to welt two 1/4" thick sections of steel flat bar together to create an 8" square. I bought bolts to match the thread pattern of the stock trailer wheel studs. (boltdepot.com) I dipped the heads in muratic acid (available at home depot for pool cleaning). This allowed me to drill holes in the plate and then weld the bolt heads in place.

Next I began working on the spare tire mount frame. I decided against welding it directly to the tub since it would make things easier later if it was a bolt-in-place unit. I can change it out if I ever change wheel diameters, tire thicknesses, or have problems with the trailer balance etc..

After the frame was fabricated I bolted it in place with six 3/8" carraige bolts. I made the depth of the frame equal to the depth of the tire with the wheel's backspacing so that the tire rests snuggly against the frame and lip of the tub. Hopefully there will be enough clearance for the tub lid since the tire sticks up higher than the lid.

Relocating the Hand Brake

As I mentioned in my last post, to mount the jerry can holders up front, I had to relocate the hand brake. This is a nice feature since it keeps the trailer from rolling away when you have it disconnected at camp, so I wanted to keep it intact. I just unbolted the original mounting bracket and moved it out to the side of the trailer. You can see the old location where its rusty in the photo. The j-bolt was now too short, so I used a turnbuckle to extend it. This assembly now sits underneath the jerrry can holder frame.

Mounting the Jerry Can Holders

This is the location I originally wanted to mount the jerry can holders. This frees up space on the traingular tounge area for a dry box to house my electrical components. These projects were my inspiration: Pic 1 Pic 2

However, I'm not sure how they accomplished this. When I tried mocking it up, I was having alignment problems with the metal strap that holds the can in the holder. The holder physically fits in the spot along the tub in front of the tire, but when you try to get the can out, the metal strap hits the lip of the tub that hang out over the holder. See the green line below. I didn't want to try to mount the holder titled since it would difficult and would look strange. Plus it would be hanging out there... an easy target for rocks and trees.

I decided to sacrifice the space up front and mount the cans back to back standing vertically. This keeps them safe and easy to access. By redesigning my dry box using steel (rather than a store bought truck box) I can still make it fit.

I had to relocate the hand brake to fit the cans in this orientation. To allow the brake cable to sit under the cans, I had to elevate them off the tounge rails using 1.5" steel tube. Then I welded a frame to separate the jerry can holders (the can't be mounted back to back since the metal straps hit eachother at the top of the holder where the pad-lock hole is). The frame also provides stability to keep the holders from wobbeling/vibrating too much.