Cayman Islands DIY M416(US) / M101 (CDN) trailer

[mmajsw]

It took me 5 weeks to get the trailer painted and the shock absorbers installed. Life just kept getting in the way of play....work! But the trailer is back on the wheels.
After it was on the wheels, I had to weld the top of the shock mount and when I went into the trailer. I was surprised to see how much the suspension dipped. So, I had a buddy of mine come and sit it in with me. Our combined weight was 375 lbs and the trailer dropped about 1.5". I though that was too much so decided to add leaves 2 and 4 that were initially removed. The frame to axle distance went from 8-1/4" to 9-1/8". But our combined weight now dropped the trailer only 5/8". I felt that was better as this is still going to be a utility trailer of sorts and I never know when I will need to carry a heavy weight. More polyethylene inserts we added to the additional leaves and are continuing to allow smooth movement of the springs. I feel that the suspension is working as it should.
Some minor welding to be done and then it is time for fiber-glassing.

I got hold of an HP book called Fiberglass and other composite materials and with the information inside and well as reading up on the internet, especially the West Systems Epoxy fiberglass whose products I will be using. If it can work on a boat submerged in the water for years on end, it can work on my trailer that will at the most get rained on. Although the wife did say that since it will be waterproof, it can be turned into a swimming pool if needed. Hmmm... ... an expedition swimming pool!

But the day is still ahead of me, so back to work. Will be starting on the fenders today as they are small and if I screw up, not much material is wasted.

 

[mmajsw]

One fender is complete. The method I used was this.
After cutting the pieces of plywood to fit, I pre-coated both sides and the edges with epoxy resin and placed it to dry overnight. This would minimize the absorption of resin when the actual fiberglass mat was put on. After 24hrs of drying, I lightly sanded each side and ends with 80 grit sandpaper to give the new resin a surface to bond to.
Then I dry fitted the pieces in the fender and again pre-wetted the surface before placing the pre-cut mat. When the mat was properly positioned, I covered the mat with more resin until it was thoroughly wet. In the image below, I took a quick break to take the pic before applying more resin.

Then I let things dry for about 10 hrs. The now rigid fender was care fully removed from the metal to ensure that there was no changes in the angles (although it was quite rigid) and turned over so that the underneath could be done.

The above process was repeated to place a layer of mat on the bottom. The edges were trimmed when the epoxy was semi-hard with a craft razor blade.
The end result is a strong, waterproof plywood fender. Once it dries, I will re-sand the edges and add a third coating to the ends, then it will be secured into place with 3M 5200 marine polyurethane sealant/adhesive. I have been playing with the 5200, testing how it secures various items and believe that it will do the job. That way, I do not have to introduce any holes into the fender that will potentially allow moisture to seep in and eventual rot the plywood.
As the epoxy resin has to be protected from UV light to prevent degradation, the top will be coated with Hammerite paint (to match the frame). All that is needed is to scuff the fiberglass with 220 sandpaper and paint away.
The inner fender well will also be scuffed with 220 and then coated with bed liner. One down, one to go.

 

[mmajsw]

And the first fender is in and painted. I followed what was mentioned above and need to add that the plywood was clamped in place to ensure it was well secured during the bonding stage. The 5200 was placed on both the inside and outside edges of the supporting metal to ensure that the edges were sealed. After the bottom was given a couple days to dry in our 80% humid air, the clamps were removed and more 5200 was placed on the top joints to secure and seal the plywood to the metal. A few more days of drying and it was covered with black Hammerite hammered finish paint to match the other painting that was done. Both top and bottom were sanded lightly with 220 grit sandpaper to give the paint something to grab on to. It might not be show quality but it is solid. The underside of the fender will be coated with bedliner once both fenders are completed.

 

[mmajsw]

Question - how long can an opened 10 oz cartridge of 3M 5200 polyurethane sealant/adhesive last before drying out? Local cost is about US$40 for black and about US$50 for white and clear
It cures by absorbing moisture out of the air.

My answer so far is 10 months! I bought a cartridge when I had to reseal my new windshield that was replaced in Sept/17. Because I did not need much, I decided to see if I could make it last - especially at the above prices.
So the remaining sealant was removed from the cartridge gun and the nozzle was wrapped in multiple layers of painters tape and place in my garage fridge at 38F. I had used it twice between then and now (repeating the sealing process each time after use).
I finished the tube last weekend when I secured my trailer fenders in place.
You do have to dig out some of the hardened sealer from the tip, but it was usually a 1/4" or so before you had the flowable stuff.
I am opening a new tube and this time, in addition to the tape, I will also be placing it in a zip-lock bag with as much air that I can get out of it as well as adding a small package of silica gel.

 

[mmajsw]

After a 2 week hiatus, I am back on the job.
Continuing with plywood, I cut out the front panel and did the final bit of trimming for a loose fit. Then I removed an additional 1/16 all around to allow for the fiberglass epoxy on the edges. I will seal all gaps between the metal frame and plywood. Note the reliefs at the bottom edges for the 1/4" metal frame on the trailer bottom.

After the first coat of fiberglass epoxy, you can see in the image below where it was absorbed into the wood more in some areas than others.

After the first coat was dry, I sanded the glass with 80 grit paper and applied the second coating only on the outside face. The edges got 3 coats and I ensured that all gaps in the layers were fully sealed. Luckily, there were no that many to worry about.
The inside will be finished with bedliner so I did not add an additional fiberglass layer.

On the metal frame in the trailer, I made sure that all welds and corners were smooth and free of debris. A final coating of Hammerite paint was applied so that it can be dry by tomorrow afternoon. The mounting of the front panel will occur tomorrow after I come home from work - if all goes well.

 

[mmajsw]

With the front panel dry, it was time to finish it. Epoxy fiberglass does not like UV rays, something that the sun gives us in abundance in Cayman. As the epoxy fiberglass came from a marine store, I asked what would be a good paint to use a protection?
There were a number of choices but in the end , they recommended Rustoleum Topside paint in gloss finish. I got a quart can of white and had it tinted Valspar Kiln Clay, which just happens to be an extremely close match to my Land Cruiser's factory paint.

I installed the front panel into its position and used a pencil to mark the outline of what would be exposed beyond the metal supports. The plywood was then removed and the glass surface to be painted sanded with 80 grit paper until the surface was dull. Wipe with acetone and a cloth and the first coat of paint was applied, going about 3/8" over the pencil line. Following the can instructions, it was put away to dry for 24 hrs. This afternoon, I sanded the paint with 220 grit sandpaper, wiped it clean and the second coat was applied. This is now drying for another 24hrs. Tomorrow afternoon, I hope to install the front panel using 3M 5200 polyurethane adhesive. Some creative clamping will be needed!

A partial view of the front panel, showing the bonding areas unpainted and the open areas painted.

Having some time to kill before the sun set and time to put the tools away, I decided to make a sample piece of a side panel to see how it would look and fit. It would also allow me to check the fit angles at each vertical support.
Using scrap pieces of 3/4 plywood, I measured and cut out each piece, ensuring that the angles were the correct orientation and fitted them into position. It worked out pretty good at each test position, and it would require me to only make 3 long cuts. Each piece will be cut a couple inches longer than needed, then trimmed to fit.
The pieces had to be held in position with clamps and a piece of wood for the photograph. Gap between each piece is about 1/32" of an inch and will be used to hold the fiberglass epoxy bonding agent. Some fiberglass strips for incorporated to add strength and rigidity at the joints

 

[mmajsw]

The side walls have been cut out and now the long task of fiberglassing begins. The pieces are just sitting loosely in place, not screwed or bonded together as yet.

Gaps between the wood joints range from nothing to 1/8. But some thickened epoxy will take care of the butt joints.

Then 4" wide strips of fiberglass mat will be used at each joint for rigidity. The same epoxy use as as the front will be repeated - inside will get one coat epoxy and the outside will get 2 coats epoxy and 2 coats of paint. Lots to do before any more major update will be given.
I have ordered a gallon of Monstaliner with Desert Sand tinting to finish the inside; whenever it gets here.

 

[mmajsw]

After getting a loose fit, I took all the pieces from one side and gave everything the first coat of fiberglass resin to seal the plywood. When this had dried for 24hrs, I sanded the 4 contacting edges and made some epoxy peanut butter (mine was actually silica butter) and proceeded to epoxy the edges together. I was a case of put too much on, push the wood strips into place, then clamp everything together so that it does not move. Then try and clean off as much of the excess as you can before it starts to harden. But I used a slow cure hardener, and was able to get most of the excess off. Then cover and wait 12 hours before moving.
Some of the epoxy had stuck to the metal, but it released after prying it off. I was gentle as I could because I thought the joints would have been a bit on the flimsy side, but was moderately surprised on how solid the 3 pieces were. As a result, I will forego putting the fiber glass strips that I was going to use to strengthen the joints.

A view of the passenger side, inside face of the trailer wall, showing the areas where the epoxy was absorbed into the plywood.

A bit of sanding with a flapper disc to remove excess blobs and drips, followed with a final sand with 220 grit sandpaper to roughen the old surface and the exterior received the second epoxy coat. This is a view of the exterior passenger wall, after the first coat.

As usual, all the outer edges received 3 coats of epoxy.

 

[mmajsw]

Before installing the sides permanently, there was a few bits of welding to the done to the vertical supports.
I wanted to be able to create a table for use when for camping or other reasons, so I welded a couple of pieces of bed frame that I had in stock. The pressure on those pieces would be minimal, so the thin material was sufficient; and I did a bit of recycling. Before installing, I drilled a 1/4" diameter hole in all the brackets so that a bolt or other type of locking pin could be inserted through the metal and then into a corresponding hole in the plywood table top to prevent movement.

Tack welded in...

Test fit with the plywood. Here, I am using a 4'x2' piece of 3/4"AC which I am currently favoring. I have a piece of 6'x2' that can also be used but I will need to do some load testing first. I intend to finish it with one coat of fiberglass then cover the top with rubber matting glued to the plywood.

Brackets were installed on both sides of the trailer.

I had cut out the front box base supports and tack welded them in, but due to the rainy season, I never got to fully weld and finish it.
So this morning, got up early and welded all the brackets. Then I cut and fit the base for the front box. It is a close fit and has to be dropped in. You cannot lift one side, then the other as it will not come out. Once coated with fiberglass, it will receive a thicker rubber mat for the cover.

Finally, a look at one side panel painted and in place. I did a second coat of paint for a more uniform color.

 

[mmajsw]

I wanted to have a brace at the top of the trailer at the rear to both add strength and to prevent the side from spreading under load but at the same time have a surface that can be as weather /waterproof as possible when I install the cover. Some creative cutting and thinking was needed, so I came up with this. A mirror image unit was made for the driver's side. Looks distorted but it isn't - I was using macro mode on the camera.

Now the 2x2x1/8 top rail, when secured to the brackets, is sturdy and secure.

Passenger side

And driver's side

I finished it off by welding the joints and painting all the exposed metal.

The next thing to do is the rear doors. I am still weighing whether to build a drop down door or a swing out door.
The main benefits to me of a drop down door are that it can support long items being carried by the trailer and also be used as a table.
Whereas a swing out door would allow me to carry the spare tire on a rear door. I could make some small drop down tables to hang from the swing-outs, so it cancels out one benefit of the drop down. The swing out door would need to be quite sturdy to carry the spare. But then I could make them different sizes.
The irrational thinking goes on and on, but in the end, it just might come down to what I think looks good!

 

[mmajsw]

Well, after a little more deliberation, I decided to go with the swinging doors. The main reason was to offset the weight of a battery and associated electronics that will be present in the front box. I can readily adjust the tongue weight when packing the trailer. But when it is empty, I have to ensure that it can be easily moved around by one man. So with that decision out of the way, it is time to make some heavy duty hinges.
I had previously looked at what was available in the stores locally, but as to be expected, the choice were more related to home and yard gates. They were not sturdy enough and definitely nor suitable to my liking. One on of my trips, I looked at buying weldable hinges and liked the looks of this...

... but it was single shear. Double shear hinges were much stronger. The difference is shown in the diagram below. The top and bottom pieces will be welded to the trailer and the center piece will be welded to the rear door.

So, using materials at hand, I proceeded to make some. Main ingredients are 1" DOM with 0.250" wall and a length of 1/2" steel rod.

Now the rod will not fit into the hole, but that is addressed later.

The first thing was to cut the tubes to length. I did 2 @1.5" and 1@3" for each hinge. After the pieces were cut to slightly longer than needed, the ends were cut square in the lathe. Then I used a new 1/2" drill bit and drilled out the center of each piece so that it could fit over the rod. Drilling slowly and using lots of cutting oil results in a very smooth inner bore.

Finally, the pieces were fit on the steel rod. I still need to make or buy some brass washers to fit between the pieces of 1" tube. Also, the pin will need to be secured into location so that it cannot be easily removed for security reasons. This might be done by welding or a set screw - haven't made up my mind yet. I want the gates to be removable if needed without any major issues or I would have welded the ends of the hinge for maximum security and strength.

A dry fit of the pieces. The outer ends of the two smaller pieces still need to be rounded for looks and safety. But it is enough to show what they will look like.

One down, three to go!

 

[mmajsw]

Well, after a bit of cutting, lathe work to get the ends of each piece of tube square, drilling each one out to allow the 1/2" rod to fit and re-drilling 3/8" ID brass washers out to fit the 1/2" rod, I have all 4 hinge knuckles and pins completed. I also cut our the pieces to weld to the knuckles so that they can be mounted to the trailer body and the yet to be built door. Is did one from 1/8" steel and another from 1/4" and tested it. The 1/8" steel seems strong enough but that can he changed in needed.

The next bit of work is to work on the pins. I will drill and thread a setscrew into the center knuckle to hold the pin in place and prevent them from coming out - accidentally or intentionally. The set screw will only be accessible when the door is open. Then I have to add a grease nipple to each of the smaller knuckles so that the pin stays properly lubricated.
Then finally some perpendicular braces for the knuckle to body.
Slowly but surely.

 

[mmajsw]

Spent a bit of time cutting metal in order to brace the hinges but once the welding was done, it was time to put the hinges on the trailer.
I used a 3' length of 1/2" steel rod to ensure that everything was lined up before welding the hinges to the body. I ended up using 3/32 6013 welding rod as I wanted to get a reasonable looking finishes to the welds. I tack welded everything up before doing the more permanent welding.
I ensured that all hinges were moving smoothly and the center of the 1/2" rod was aligned with the edge of the corner frame. Welds might not look pretty but I had not removed any slag of did any sort of cleanup as I knew more welding was coming.

After this, I cut 1" x 2" x 1/8" steel tube to create the doors. Door size is 22" high - 1 is 18" wide and the other is 26" I went with a 60% and 40% set of doors - just my choice. Could have picked any ratio since they were being made from scratch. The passenger side gets the 60% wide door and the tire. Doors are already squared and tack welded and will be test fitted tomorrow.

 

[mmajsw]

With the doors welded up, I clamped them back on the hinges and tack welded the hinge to the door. Disassemble the hinge and weld the hinges to the door. Once completed, put both doors back up and then work on the small parts like lips for the weatherstripping, limiters for closing the doors, tabs for security locks, surfaces to bond the plywood inserts to the doors and a host of little things that take more planning than actual execution. But in the end, I got the doors in place and all works well.

I started to work on the hinge security. My original idea was to drill and tap holes in the center piece of the hinge and use 1/4NC x 1/2 long set screws to hold the pin in. But when installing the first one, the tap snapped when transitioning from the outer piece to the center pin. There was about 1/16 of the tap sticking out so I tried to weld a nut to the bit of tap so that I could extract the broken piece. Needless to say that did not work. I will address the removal of the tap later.

View of the broken tap in the hole

So, on the other hinges, I drilled a hole slightly smaller than the diameter of a nail, cut the length of the nail to be a little less that the depth of the hole, and drove it in as a friction fit. They will still do the job of preventing the removal of the bolts used as hinge pins, but can be easily removed once the tailgate door is opened.

The final step is to cut the necessary pieces of plywood to fit into the rear door openings. They will get the usual fiberglass treatment and a combination of 3M 5200 polyurethane sealant and stainless screws to hold them in.

Here is the plywood cut and fitted into the small door.

But I have to work on mounting the spare tire to the large trailer door before cutting wood for that door.
Here I have test fitted the tire to get its approximate position to make the support brackets. I had to ensure that the door would swing open to at least 90 degrees and also allow access to the bottom corner of the door for the security lock.

 

[mmajsw]

I decided to take the easy out with the spare tire mount on the trailer. Use what material I had in hand and not to make anything too fancy.
The first thing was to get some vertical support in the door to hold the spare tire mount. Two pieces of 1x2x1/8 were welded into position, centered along the proposed position of the center of the tire. I was going to use only one vertical but figured that two would give more strength.
Next was to measure how far out the rim would be to allow the tire to just touch the door. That was 5.5". Looking around my scrap pile, I found a piece of 2" diameter black pipe and cut the 5.5" from it. Then something to bolt the tire to. A piece of 6x8x1/4 was found. A few minutes with the welder and you have the following...

... with a piece of 1x2 welded on for horizontal support. I still need to add some braces for the plate as it is, at the moment , just a butt joint.
I will eventually shape the plate to be more circular once I know exactly where to place the tire.

 

[mmajsw]

New pieces of flat bar were added to the new vertical supports for the plywood inserts.

I had obtained some 75 LED stop/turn/reverse lights from China so they needed to be mounted. I could have just bolted them on but decided to make a metal surround for them as they are all plastic and one can never tell when a piece of tree or other item could hit them and break them off.
So using some 1" x 12 gauge angle, I created the following.

They need to be welded to the trailer frame. I might get some mesh to cover them for added protection.

I wanted to add some shelves in front of and behind the fenders to carry fuel/water cans or ammo boxes with whatever is needed. Off to bend and shape more metal!
I started out with 2 x 2 x 1/8 angle, a few cuts and some welding and I have the following.

Internal size is 15" x 9" wide. One down, three more to go.

 

[mmajsw]

The front was also done.

In addition I added a piece of 1/4" flat bar to reinforce the joint where the angle iron pieces from the draw bar were welded to the frame. The bar was pre-bent to fit the existing angle. The opposite side received the same treatment.

With all four corners done, I cut a piece of plywood to see how the fuel can would fit . Looks good with ample clearance all around. The plywood will get the usual fiberglass treatment. I tested each shelf with 200 lbs of weight to see if there would be any issues. They all passed with flying colors.

Now to figure out the best way to secure the fuel can in place. I will be using tie down straps but how is the big question.
A quick trip to the local hardware store netted me 8 1.5" U-bolts. All I had to do was to weld them on in the middle of the opening and I have my hooks for the tie down straps. That was easy!

I believe that the welding is now completed. Forgot the taillights still need installing as well as tow hooks and a trailer hitch! (Does it ever end?) Time to clean off flux, rust, etc and paint the metal. Some wood preparation is also needed.
The Monstaliner for coating the inside is here. That is good because the next major installation will be the sides and bottom!

 

[mmajsw]

Had a few minutes today so I welded the stop/turn/reverse light brackets on. There is about a 1" gap between the light bracket and the fuel can. I decided that I can make a positioning fixture for the fuel can so that it is placed in the same place at all times - away from potential rubbing against any metal. But at the same time, the ring should be able to be removed easily if needed. But that is woodworking.
I tried using a strap to hold the can down and the loops work very well. Did not remember take a picture though.

Looking from the rear, I can see that some side and rear marker lights would be advantageous from a safety point of view. One more set of things to buy! I figured that two red ( for the outer ends of the fuel tank shelf) and four orange lights (two for each side)should do the trick.

 

[mmajsw]

Ten months after I started this project, I decided that today, due to being overcast and very humid, I would install the sides. A dry fit was done to get the inside measurements of the pieces of wood that would apply pressure to the sides. The pieces were cut 1/2" oversize from old 2x6s I have lying around. A good thickbead of polyurethane sealant was applied to the metal supports and corners and I then inserted the sides in place and clamped the tops to the metal sides using C clamps and short pieces of 2x6. I then inserted the longer pre-measured and pre-cut 2x6 and jammed them in place. A quick walk around to ensure that plywood sides were touching the metal supports and that the sealant was squeezing out past the metal in almost every contact surface and I was happy.

Here is a look at the clamping arrangements.

Along the sides...

And to add pressure the bottoms.

This will sit for a minimum of 48 hours before the clamps are removed. It is looking like a trailer again.
Then, I will measure the bottom piece and cut it out and apply fiberglass. I will also start on the design of the top cover.

 

[scrapdaddy]

A lot of good work going on here, but we lost your last pictures from Oct.1st forward.