Ultralight foam build

[KCStudly]

Oh, a CNC router. I must have missed that. Here I was thinking you had done all of that work with layouts and a template.

[Fred Trout]

Likewise ....

would be nice to have one of those in your garage

[GPW]

If ya’ got it ...... Use it !!! We found the CNC invaluable for cutting out the FoamStream ribs ...

[R. W. Alexander]

With work and other commitments, I have had to put my build on hold. But I have some time now for the tear drop. I have had time to re-evaluate my design, over the past few months. I decided to do a 2" foam with 1/4" plywood for the base or SSP panel. Along with 1" walls and top. I didn't use the galley that much on my first build so I am eliminating the galley in favor of some side doors. More to come later.

[GPW]

RW, Great idea for a wine rack ...

[R. W. Alexander]

Okay, everything I've done at this point has been shelved. The CNC bottom panel will be saved for a future build for family. I redid the design for the tear, so I needed to do a new bottom section. I visited the B.O.R.G. (big orange retail giant) today and got some 1/4" ply for the bottom along with some 2" foam. I also got some 1/8" ply and 1" foam for the walls, along with some nice 2 x 4" cedar that will be ripped into 3/16" strips.

[R. W. Alexander]

Some photos of the base section. Since the bottom panel will not sit on a trailer frame. But be attached to Torsion axles. The bottom will be built as a SPS panel. The laminated beam is for mounting the axles. I will add the 2" foam inside, then glue and clamp the bottom panel. Once all the individual SPS panels are glued in place the trailer will be strong. My last tear drop build weighed in at 550 lbs. I'm aiming for somewhere in the 300 lb. range.

[R. W. Alexander]

Welded the frame and painted it. The wood base weighs 55lbs. And the steel frame weighs about 33 lbs.

[GPW]

Wow, that’s really Old School minimum .... But we know it works if everything is made right .... Should be VERY Light !

[seanc]

This looks like its going to be light enough to pull with a bicycle, I like that you're pushing the limits!

Can you clarify for me how you're attaching the wood base to the frame? i.e. along the length of the steel angle or only at the axle or tongue, with glue/bolts/screws?

Keep up the good work!

[mikeschn]

I like this design. I like that the tongue is attached to the stub axles. The T@B does something similar...

When you bolt thru the floor, and you going to have a steel plate on the other side of the floor?

Mike...

[R. W. Alexander]

I like this design. I like that the tongue is attached to the stub axles. The T@B does something similar...

When you bolt thru the floor, and you going to have a steel plate on the other side of the floor?

Mike...

I attached a more detailed CAD drawing of the torsion half axle. The torsion half axle sits directly under a laminated 2" fir board. This will prevent compression of the foam SPS panel, and acts as a regular axle in keeping the 2 half axles aligned.
The 3- 1/2" long by 5/16" hex bolts go through to the axle plates and have lock washers on the ends. As for the top of the bolts. A simple 1 -1/16" fender washer will provide plenty of area to prevent compression of the 1/4" plywood. With this set up I have eliminated some unnecessary weight.

In my opinion I think we overbuild the bases of small tear drops. A tear drop that weighs under 1500 lbs can do without a full metal trailer frame. A properly designed floor can handle the weight loads. I had a commercially built tent trailer in the 1980's that only had half axles and OSB board with a few strategically placed pieces of plywood
for support. And it weighed a lot more than this tear drop.

[R. W. Alexander]

I cut out out the SIP foam wall panels.(1" foam with a 1/8" plywood on one side) On the exposed foam panel side I'll start gluing on some cove and bead 3/16" thick strips of cedar. For the inside of the side panels I plan on inserting some 1" square wood supports where it's routed out. They will allow me to connect some lightweight laminated foam boards for cabinets and storage shelf's. I also had to make a few changes to the door and the door window shape. I also didn't want to put in a galley lid, but the wife would be happier if their was one... so in it goes.

[GPW]

Nice work !!!

[KCStudly]

Nice work with the CNC.

I'm curious about the double cut around the doors. What is the plan there?