Winter 2015 Tiny TT Build

[jadedave]

Yes this is something Im still trying to figure out ,.. The 2013 Subaru Forester has a towing capacity of 2400 lbs but the newer and bigger 2014 Forester was down graded to 1500 lbs ,, It seems as if Subaru is trying to discourage towing in the US while promoting it in Australia, the UK and Europe (towing caps in those countries are double or more what they are in the US.

[jadedave]

Finally the trailer chassis has arrived. I had fun hooking up the new trailer and fiddling with the brake controller on the way home.. First step was to remove the 65 lb rear ramp gate . I will try to sell it on Craigs list.. After leveling the trailer , I bolted on two wood rails to widen the overall box width from 72 inches to 79.5 inches. Saturday morning I hired my daughter and boyfriend to help me stand the walls and fit the spars into the wall notches. I had to do some custom fitting at the interface between the aluminum chassis and the wood structure . The trailer without the ramp gate weighs about #475 and has a tongue weight of #65.

[KCStudly]

Off and running.

I'm curious how you sealed the end grain between your extension rails and the fender? Hoping that you used some sort of sealer there to protect the end grain. Perhaps they got sprayed with the varnish, too?

[dales133]

Havnt seen this build until now, great woodwork as KC said and a great looking trailer frame too

[jadedave]

Good question , in this case I smeared some silicone into the end grain and smushed it tight to the fender. If I do everything else right these bolted on side rails will only see water on the bottom side . I was thinking of using some elastomeric coating underneath like they use on trailer home roofs. also the bottom half of the rails are redwood.

[jadedave]

After the spars were installed I proceeded to bend 3/8 thick pine ribs running from the front to the back of the trailer. One of the curves in the rear of the trailer was too tight to bend the ribs and I had to laminate two 3/16th strips to make the bend.

[jadedave]

Here are some photos with the one piece .040 aluminum roof in place . We siliconed the edges and ran rope across the box to cinch the metal down to the frame.

[S. Heisley]

Since that trailer is too big to fit in the garage, I think you've got the right idea, to get 'er weather-tight as soon as you can.
...Cute mail box.

[KCStudly]

It looks really good. Nice shape and clean work.

Will there be insulation? (Sorry if it has already been mentioned.) If you are planning on doing it after the fact, I would really hate to be working with foam in a confined space like that, but I guess it is a lot larger than a typical TD, so maybe less of an issue. I'm just thinking about the dust depending on how you plan to fit, cut and fair any of it (assuming you will be using foam board).

You must be planning to insulate, right?

[jadedave]

Yes , the walls were insulated when I prefabbed them in the shop. Once the trailer arrived I laid down foam board on the flat bed floor before assembling the box .. For the ceiling /ends I plan to wrap foam board sections in ribbed indoor outdoor carpet and fit them between the spars . (They will be removable to allow access for wire runs. All of the exterior walls floor and ceiling will have 1 inch isocyanurate board R value 6 . If there is room I may be able to add some 1/4 inch mylar bubble insulation in the ceiling to boost the R value to about 9-10.
One thought I had about the roof aluminum is how much the 23 ft long sheet (seamless) will expand and contract within the temp range experienced in a typical summer day. What will the sheet do as it is fixed at the edges but not in the middle.. I cant seem to find a good aluminum expansion calculator.

[KCStudly]

13 x 10^-6 / deg F

So if you have 10 ft, or 120 inches, installed at 70 deg F it will grow to 120.047 inches at 100 deg F. Multiple thermal expansion rate x length x temperature change. It will grow at the same rate in all directions, so if you are 5 wide it will grow half as much across the width, as an example.

Here's an online calculator.

[jadedave]

Based on the calculator , looks like the alum could change about 1/2 inch over 23 ft assuming a temp range from 50 F to 130 F.

[KCStudly]

Hmm, I only get 0.287 inches for 23 ft and 80 deg rise. Did you remember to change the default expansion rate to .000013?

If you installed it at 50 deg it could grow a little more than 1/4 inch.

However, if you installed it at a warmer temp, say 70 deg, it will grow at 130, but it will shrink at 50. Don't calculate for the range of temperature, calculate the deference from your neutral base line (at installation); colder shrinks, hotter grows. Same rate.

[jadedave]

Thanks I see that I was using the metric rather than the English coefficient.. So if I screw it down at say 60 F and assume 60 degrees up and 60 degrees down ,.. I get about .21 inches each way (temp) over the total 22.5 ft...

[KCStudly]

Yup. That checks out.