Wednesday, May 17, 2017

CHATTANOOGA CAR SHED - UPDATE

Latest photos show the completion of three walls. In a prior post on the shed, I mentioned that I used Chooch flex wall and Micro-Mark Factory Red Brick adhesive paper. These were formed over the base wall made from a double layer of plywood to get a good thickness for strength. You will notice one wall has the limestone pillars painted a light gray. This was a test that I found very satisfactory. It is a medium wash using a craft paint named FOG from Michaels art supply. 

 
Next was to create a jig to build the trusses / roof supports as seen below. I used the upper edge of the end wall as the guide to place #18x5/8" wire brads. The jig base is  left over piece of pine. The trusses are Pastruct #90655. First was to cut off the one beam in order to get it to flex then removed one of the remaining V sections from each end. So far I have 8 completed with two more to build. Next will be constructing the roof; I plan on using Evergreen sheet styrene, part #4250, V groove .040" thick. Each section is 6"x12". Amazingly, the foot print I made was perfect such that I did not need to cut to fit any section. Four sections laid side to side fit perfect!
Fast forward... creating the jig is usually the biggest challenge and that was no different for the roof. But how to get the .040 styrene to bend and hold its bend was a conundrum. A few conversations later with friends, they suggested a heat gun. But I needed a solid base to allow the styrene a solid base to reform.  So a small jig was built. Scrap 3/4" particle board was cut into arches in line with the ends of the car shed to accommodate one section of styrene. Aluminum flashing was to be the solid base and secured to the arches. 


Anchoring one end of the styrene with clamps, I moved the heat gun over the surface until the plastic began to relax. One great idea from Ray Russel to help hold the new shape was to place a cold towel immediately onto the styrene to lock the position. In the end and although it came out reasonably well, the problem was that I could not count on each styrene section to remold itself into an exact position so that all 5 sections would line up cleanly. I need to be bale to have a solid even arch base to shape these .040 sections. Why .040? Because they have the V grooves far enough apart to replicate the solder joints shown in the photos!
Sharing my dilemma with club members, Steve Lang suggested taking two .020 sheets, glue them in the shape of the arch and that could serve as a sub roof to hold the .040 sections in the arched position. "But Evergreen doesn't make them 1'x2'." Steve did have sheets that size - exactly! Love how a plan can come together.
Starting with old 3/4" plywood you can see I cut 8 arches and secured to a base. 
I was unsure how to clamp the roof and then the duh moment... 
add spacers.
 JB Weld epoxy was my choice to secure the aluminum; speaking of which, it was also the exact size needed when purchased, 1'x2'. Very happy several materials were ready to use.
 Here is the jig with the sub-roof being prepped, limed up.. 

The two .020 sheets were lined up on the aluminum and clamped. Leaving one side clamped, the other side was opened in order to apply the Ambroid PRO-WELD. I went to a much larger brush and wider container since the accompanying brush was way too small when I needed to get a lot on quickly. But it worked.
So far so good. However there was a slight uplift to the sides of the sub-roof. I am hoping that by clamping the V groove sections onto the sub-roof using JB, and onto the aluminum jig to hold the curve, the end result will be close if not spot on.
First is to line up the V groove styrene sections.
 One edge was then secured with clamps to hold the position.
JB Kwik (5 minute epoxy) was applied to the other edge. After that hardened, waiting about 1 hour to cure, three more applications with hardening time has one section secured. Below two sections are in place. The other two sections are place holders to ensure alignment.