Winter 2015 Tiny TT Build

[OP827]

A Craftsman work, and really nice looking trailer.
It really looks like you know what you want and doing from start to finish.

I would like to learn more about considerations of the temperature expansion relevant to the trailer skin. I could be missing something here, but these materials are being used for trailer in such combination for quite sometime, glued, screwed, riveted. I thought that skin expansion values are usefull to know when you can assess how other pieces such as wood and frame will behave with those temperature change and then make a judgement whether there is any issue with stress. Aluminum trailer frame and wood will also change their dimensions with temperature. Did you compare the temperature expansion values of wood frame against the skin? Linear Temperature Expansion Coefficient for Aluminum (10^-6 in/(in oF)) is 12.3 vs. wood across (perpendicular) to grain is 17 and wood parallel to grain is 2.8. I do know see how this is going to be an issue if the materials are positively attached with glues and screws, but I am not an expert in this field, it is just a thought.
http://www.engineeringtoolbox.com/linear-expansion-coefficients-d_95.html

[jadedave]

Most of the wood structure is pine and fir with a coefficient of approx. 2.8 vs aluminum at 13 . The AL skin will get much hotter than the wood underneath , however the entire 23 feet will never be fully in the sun . Overall the above differential expansion is probably not much of an issue but time will tell if problems appear.

[jadedave]

The exterior of the trailer is finished with the exception of the windows and the entry door,, Now Im installing some of the interior parts that I fabricated in Feb and March . Everything is fitting together fairly well with only a few glitches that were easily worked around. Once he interior structure is complete I will be able to start on the electrical and mechanical systems.

[OP827]

The quality of your carpentry work looks amazing! Thanks for sharing and looks like you are going to finish it off pretty soon .

[jadedave]

Thanks , It helps that I was a professional cabinet/furniture maker for over 35 years.

[lfhoward]

Love the modular nature of your build, how you assembled all the parts ahead of time and then bolted them together. I am making a trailer that is too tall for a garage, too, so being able to assemble the structure and weatherproof in a day or two will be critical.

[luscombe]

I like your trailer so far. I am building something similar but with no wood. Wood is a killer for weight. I am using .032 aluminum riveted to 2x2 channels of .032. I built my trailer frame to accommodate the water and waste tanks and keep the weight low in the frame.My trailer frame came in at 490 pounds as it was titled at the DMV. Have you thought out your plumbing? You did a great job prefabbing the interior.

[S. Heisley]

The interior is looking snazzy!

[jadedave]

If you are careful about the species of wood and how it is used then it will weigh less than you might think. Throughout this project I have tried to select the lightest weight to strength wood that I felt adequate to build a strong yet light enclosure. For the walls I have used what is commonly called white wood which is a name for a mixture of spruce , fir , hemlock , (home depot ) when dry it is very light yet is somewhat fibrous and tough . Most of the studs were 1 in by 1 in and the top curved rail pieces 1 in by 1.5 in . For the spars I selected clear vertical grain Doulas Fir . The fir is heavier than the white wood but with the span of 77 in I needed very strong wood ( the spars are 1.25 in by 1.5 in. ) . Also for the bent roof ribs I used beetle kill pine as it was cheap , light and available in 16 foot lengths. Inside I used cedar for parts of the hollow core panels as well as 1/8th Alder ply for the panel skins. The only place I used a heavier wood was for the mahogany trim edging the panels , windows and kitchen facing. This was a small amount and added the look I was wanting.. At this point I am thinking the finished trailer dry weight will come in around 1600 to 1650 lbs . Once I get the windows and rear door installed I will take it to a truck scale and find out .

[jadedave]

Here are some photos of the foam board ceiling panels which are being wrapped in a ribbed indoor outdoor carpet I found at Home Depot. This carpet is made from recycled water bottles and is very light and strong. The panels are fitted between the spars and held in place with velcro strips....

I got my glass panels today as well From Kotto Auto glass in California .. Their price was much less than any other quote I received and at first I was hesitant to go with such a low quote. In the end they did a great job and I received exactly what I ordered . Here I am epoxying the glass to the aluminum hinge on one of my custom window frames . The glass will also be bolted to the glass with an experimental bolt design.

[jadedave]

Finally I have the door installed , Im still unsure about the resin window panel with sea grass and may go with a clear window. I did figure out my finish for the Aluminum skin. Since the mill finish shows every scratch and blemish , I needed a finish that would hide scratches and still look interesting. Polishing to a high gloss ala Airstream is incredibly time consuming and requires constant upkeep. I settled on a swirl finish that if scratched could be spot sanded and reswirled. To get this finish I begin by cleaning any grime or glue/calk stains with acetone and then sand the surface with a random orbit sander and 180 grit Alum oxide sanding discs. Once the surface is free of scratches and sanded to an even dull sheen I go over the surface with a 4 1/2 inch diameter velcro scotch brite disc on a variable speed drill. I try to put the swirls on before The trim goes on and overlap each swirl by 1/3 .