Tucson tortoise: Edit for photos

[rebapuck]

Switch plates are great. Makes it "yours".

[noseoil]

One thing I'm still concerned about is the finished weight, it keeps nagging me each time I do something on the build. Does anyone have some feedback about the use of 1/8" Baltic birch (3mm) for the top of the deck? I was planning on 1/4" BB for the extra strength, but is that overkill (44# for the 1/4" vs. of 22# for the 1/8" for one layer)? My concern with 1/8" is that it just won't be strong enough and might "hole" from a point load like a knee. I'll have 3/4" pink foam for a core material inside the frame, for insulation, and plan to cover the deck with sheathing while working on the inside on the build. Once it's complete, I can remove the barrier layer (most likely 1/2" OSB slabs) and add a section of carpet for an extra insulation layer & loft under the mattress (if it isn't too heavy). Played with the weight spreadsheet again last night & I'm still about 150# over the target weight of 1200#. See first sentence (above) again.

Any input is appreciated on this one. Have you used 1/8" for your deck/top & if so, what spacing did you use for the framing? Thanks, tim

[KCStudly]

I used 5 mm (3/16) top and bottom over 1-1/2 inch thk foam with quite a few cedar 2x2 and 1x2 cedar xmbrs. (Also added 2x2 blocking down the center for a butt joint seam.) Glued the skins to frame work with TB2 and to the foam with 3m green contact adhesive. I used rosin paper and a piece of 1/2 inch ply over the top as protection during most of the heavy building until the 1/2 ply had to come out so that I could close the cabin in. I have been doing as much of the finish work that I can on the bench, so there has not been a whole lot of traffic inside since the ply came out, but still enough kneeling and use that I can say I would have no problem using 5 mm again. It does have a little cushion like give (just a little), kind of like the difference between hard wood flooring and that snap together stuff that goes down over a slip barrier; but no thought at all like I'm going to put a knee through it, or that it might flex enough to break the adhesive bond. I do wear soft soled shoes, or barefoot, when inside just to make sure I don't put a toe thru while kneeling, but this is more a comfort factor (when I leave work the boots come off and the flip flops go on anyway, so it's more just a precautionary thought than a lesson learned kind of thing).

Now, all that being said, it might be a different story with 1/8 inch. I'm not sure I would go that thin w/o some really good input or a decent size test piece. The other thing is, I plan on having basic open storage space with totes under most of my galley counter. Wear and tear from cargo being dragged across the floor might be an issue, and I wouldn't want the hassle of having to allow for slightly thicker material there.

[noseoil]

I did a little more work on the deck today. Cut the foam (R-Max R5 3/4" with one aluminum skin & one vapor barrier) to lay inside the frame. I decided to go with 1/8" Baltic birch and cover it for dent protection while I'm working inside. This may or may not be strong enough, time will tell and I can always add another layer of 1/8" if necessary. Planning on doing this in the kitchen area already. I used a Japanese Kiridashi marking knife for the foam cuts. It has one flat side and one rounded side, so it marks & cuts straight in the foam. These are very nicely made with laminated steel, a soft back & a very hard & brittle edge. It looks like this.



Clamped & weighted the panels in place with a few brads for alignment in the glue, then trimmed it on the aft edge with a skill saw & cutting jig (the brown masonite thing on the deck).

[Sheddie]

One thing about it Tim, if you do find the 1/8" a bit flimsy later on, you can always laminate another layer on top. Even if you have to put it through the door in pieces, and put the joins over the frames. In fact with that thickness you wouldn't notice any bumps under the mattress if you only did the areas under your hips and shoulders, and may be knees. A product that we have just got to go under our mattress for air circulation, to help prevent condensation is Hypervent, http://www.hyperventmarine.com/products.html It is a marine product, and super light weight.

[noseoil]

Thanks for the information on the hypervent material. I had never seen it, but it looks like it would be an excellent addition to the floor under the mattress. You're right about adding additional layers where needed. Even with the urethane finish, I think PL would bond things well enough, if the surface was scuffed up a bit with some coarse paper. There's no way you would feel that 1/8" (3mm) unless sleeping with a "princess" from the fabled story (The Princess & the Pea).

[noseoil]

Working on the deck still. Here's a "bolt head cutter" for the elevator bolt recess in the deck. I used a 1 1/2" speed-bore type of bit, then re-profiled it on the bench grinder to knock it down to 1 1/4", with a slightly different angle on the bottom. It's a little "sloppy" but it works to set the bolts flush with the deck. Here's a couple of pictures to show how it works on some scrap.




Saw Franklin this morning (my buddy the welder) and he did a couple of odds & ends for me. He made some cuts in the tail light brackets to increase visibility from above & behind, much better now. He also added a couple more hangers for the conduit which will run on the passenger side, from the bottom of the tongue box to the galley (see imaginary conduit in the picture). You can just see one hanger at the top of the image on the frame.



He added a bracket for me, to deflect rocks or shredded tires away from the gas line at the "T" where the brass quick-disconnect is, just to be safe. I was worried, because the brass is pretty soft and a rock could snap it at the "T" if it was hit at high speed. Also added one more hanger to the bracket to secure the gas pipe and keep it from bouncing on dirt roads. The frame is finished now! I can get going with the build.



Have two coats of urethane and three coats of white roof coat on the bottom of the deck. The top of the deck is stained now (honey maple), tomorrow it gets the first coat of urethane to seal things up for the top. Progress, is slow, but progress and moving forward. First coat, applied before it gets too hot & dry. Much nicer working when it doesn't dry as soon as the finish hits the surface. Coated with a thinned coat, before sunrise & now it's drying. So glad the cool mornings are finally back, it's been a long 5 months of heat this year.

[noseoil]

I'm working on the side panels and have a question about the 26X32 doors. I think I've found a rough opening size of 26 1/4" x 32 1/4" with a 3 5/16" radius at each corner. Does this sound like the right size for a layout of the opening? I don't want to cut the opening without checking this dimension and don't have the doors yet. I've cut the plywood and joined the two pieces with dowels & glue & am laying out for cabinets, bulkheads, lights & wiring. Nice to be working on the structure.

[Sheddie]

Hi Tim,
how about cutting it a bit smaller for now and give it a final trim for size when the doors arrive. Or do like we did, and put the sides up with some of the cross beams in temporary and work on the interior before you put the roof on. It is a lot easier than crawling around in an enclosed cabin. That way you don't need to cut the door holes until the doors arrive.
Cheers Frank.

[noseoil]

Took a WAG on the door openings and did some cutting today. I used dowels to join the plywood sheets where the hard points are going to be in the galley. I know it costs more for the plywood than using 4/4 material, but I didn't want to cut that many blocks & join all the pieces with screws or dowels. Here's how I do the marking for the dowels. Simple & fast. Plenty strong to hold things in place until the skins go on.



Here's one side cut out and showing the basic profile. I sloped the roof line about 2" to give it a less "boxy" or slab-sided look. The actual panel size is now 46" tall. Add an inch of deck and it will be 47" on the frame. One mistake on this panel, I forgot the "hard point" for the hatch support in the galley. Need to get some cardboard and do a layout now that I have the sides roughed-in. No biggie, I can always add a block of plywood once the point is located.



I didn't have long clamps, so I used two 10' 2x4's, clamps, & folding wedges to pull the joint and put enough pressure on things for the bond. Plenty of force from this setup, quick & dirty but it works.



Here's the set clamped together and ready to rout with a reverse flush cut bit (cutter on the bottom, bearing on the top). Weighed the side once I'd removed all the extra wood. Prior to cutting out the "scrap" it weighs about 85#. Once all the extra wood is gone, it tips the scales at just 17#, much better than a solid panel and plenty strong, once the skins are glued in place. The end closest to the camera is the front, you can see the taper on the top edge to get an idea of the roof slope as it pitches toward the rear hatch. Still have a fair amount of work with the router to do, but we're moving along now. Nice to see some progress and the weather is cooperating. Highs in the 80's now, so work isn't too bad outside now. Summer is finally over, I hope!

[rebapuck]

Summer is finally over and the mosquitoes are leaving!!

[Sheddie]

Hi Tim,
we have just come out of winter, and it has apparently been our wettest winter since 1947. As a lawn mowing contractor I am hoping things start to dry out soon. But the Australians keep sending us all their crappy weather.
That profile is looking really good, can't wait to see it in place.
Frank.

[noseoil]

Here's the side frame in place for a perspective view. Thinking now about attachments, wiring, etc.



A couple inches of taper to the back really does make a difference in the look. I've always found a straight top line to be too "boxy" for my taste. While you lose a bit of height and interior volume by lowering the top line, the overall appearance more than makes up for it to me. Not too worried about the galley anyway.

Still a lot to be done at this point. The main concern is locating the "hard points" for gas springs on the hatch (side walls & hatch attachment points). I'm cutting out the hatch ribs prior to going any further. After seeing some of the "Swiss cheese" sides when it comes to hatch supports, I'm getting a sheet of cardboard to do a full size mock-up of the side, hatch, opening & attachment points. The layout is really pretty simple, but I don't trust myself to do it on paper. A full size layout will allow me to find any problems before they happen, locate the mounting hardware, and use threaded inserts (tee nuts) from the back side for machine screws, instead of wood screws. I just think it's a better way to build.

[noseoil]

Have a question about the McMaster gas springs. I did the full size layout on some cardboard this afternoon and came up with their part (4138T62) for a 29.49" open length & 16.69" closed length. I want to get some plates from Amazon to mount them on the hatch & wall panels, rather than fab something myself, just easier & quicker to buy than make. The ball ends on the plates are 10mm & the struts come with 10mm ball ends already installed. Here's the bracket & plate I can get online which will work OK for my setup



In their write-up for the struts, it says "The ball-joint fittings cannot easily be removed." This is fine as I don't want to remove the fittings themselves from the struts, but I do want to remove the ball stud from the socket, so I can use the mounting plates. Does anyone know if the ball studs can be removed from their sockets on these struts, so I can use the mounting plates with the studs already attached? Worst case scenario is to have to drill out the ball studs from the brackets and use the ones already on the struts. Not a major problem, just a PITA to have to rework new parts. Thanks for any replies. tim

[KCStudly]

Best to call McMaster and ask them. They are very good at getting the answers from their suppliers if they don't already know it.

I did find this description with the related parts: "The ball sockets easily snap right onto the stud/bracket ball—just make sure the sockets and studs/brackets have the same ball size. All sockets have safety clips for secure attachment to studs/brackets except for quick-release sockets, which do not require clips (nylon socket has a snap-on cover to securely hold the ball; steel socket is spring loaded)." - http://www.mcmaster.com/#catalog/120/1222/=u6b79y