CNC Build: The Bed and Breakfast at 4 years and 40,000 miles

[working on it]

Looks good, but might I suggest using insulated ducting for efficiency and to prevent the cold air/aluminum flexpipe from "sweating" and possibly causing water damage. Though I used insulated ducting for my A/C exhaust routing, it would still be useful in your application.

Masterflow insulated flex duct.jpg (47.28 KiB) Viewed 3651 times

I used this size from HD http://www.homedepot.com/p/Master-Flow-8-in-x-25-ft-Insulated-Flexible-Duct-R6-Silver-Jacket-F6IFD8X300/100396936

[capnTelescope]

Looks good, but might I suggest using insulated ducting for efficiency and to prevent the cold air/aluminum flexpipe from "sweating" and possibly causing water damage. ...

That's what I love about this forum. I'm out there thinking, "What am I going to do about this condensation on the duct?," and I come in and there's an answer before I even ask the question. Thanks, Working On It.

I'll probably do something like that, but not as thick. The duct doesn't go through a hot attic, so shouldn't need too much insulation.

[aggie79]

Looking good Cap'n,
I wrapped my duct with that foil covered bubble wrap radiant barrier stuff. I cut in 4" wide strips and spiral/helical wrapped it along the length. I did apply two laters but that was probably overkill.

[capnTelescope]

Looking good Cap'n,

Thanks, Tom. I'm thinking it's going to turn out pretty good.

I wrapped my duct with that foil covered bubble wrap radiant barrier stuff. ...

Yeah, something like that oughta work.

[capnTelescope]

The new piece of aluminum came in for the right side, and I failed to mess it up, so it now hangs on the right side of the trailer.

I admired that for a minute or two, and decided that I can't keep putting off finishing the hatch forever.

First, I decided to work on the top gutter. I want a nice radius in the corners for appearance's sake, so how to do that? I have a piece of 1x1/16 Al flat bar (I have never owned so much aluminum in all my life). Clamped that to a piece of PVC pipe, applied a bit of manly strength and got this:

Good for 2 corners plus a little.

Add a piece of angle and you get something like this:

I'm contemplating using Bondo to fill that corner (How tacky ). Better ideas are welcomed.

Today's agenda was to finally put the ply skin on the hatch. The hatch frame got a little skewed to the right when I installed it, and I want to get rid of some of that. So spacer blocks on the right to move the hatch frame to the left:

I ended up using two clamps, but you get the idea. I also wanted the hatch to be up a little bit so two birds, one stone.

The actual skinning went easily. Clamp on the bottom rib, apply glue to the next rib, staple, repeat on the next higher rib, etc. Unclamp the bottom rib, glue, staple and clamp. Done.

This picture makes it look out of whack because the hatch is partly up. It didn't turn out that way at all.

I did get some gap-osis between the spar and the skin.

This is due to the spar curve not matching the same curve the ply wants to bend to, and not vice-versa. Remember me muttering something about parabolas earlier? Anyway, I'm going to allow this to go as-is, because I should get less springback than if I try to force the ply to bend to my will.

The next step is to trim the edges. This was intensely tense, because this is handheld router work and I usually manage at least one goof on that kinda stuff.

I learned a couple of things that bear mentioning for anyone who wants to try making their hatch like this.

First, SAVE THE TOP EDGE FOR LAST. Until you trim the sides, the hatch won't close completely, and you will get a too-wide gap at the top! How do I know this? At least it doesn't show from ground level. I'll make it better when I do the Al.

Secondly, the direction you move the router can make a real difference in how this turns out. The guiding surfaces are the side walls and the galley spar on top. You want the cutting action to tend to force the router toward the guide surface. So you go up on the left side, down on the right, and left-to-right along the top. Fortunately, I figured this one out before I started.

There's more, but it's tired and I'm getting late.

[Breytie]

The new piece of aluminum came in for the right side, and I failed to mess it up, so it now hangs on the right side of the trailer.

If you ty to fail and succeed, did you succeed or fail?

At least you and the CNC now understand each other! It looks very good, just keep it going while it is going right.

[capnTelescope]

If you ty to fail and succeed, did you succeed or fail?

[capnTelescope]

Teardrop Time took over the last couple of weeks and I've been working less and posting not at all, so it's time to catch up. Hot weather, going out of town, and stuff I'd rather not be having to do kept me off the build. Okay, enough whining.

I made some holes in the side for water, 110VAC in, and 12VDC out. Tense moments, because it's handheld router time.

No mishaps except I think I got some sawdust down the water inlet pipe. Mounted the hardware.

I spent an afternoon at TechShop fabricating some trim pieces to fit over the top rim of the galley wall. It's a shallow "U" from the same alloy as the skin. This pic shows the trim in place on top of the galley wall, and another piece to the right, showing the bottom side.


Of course, the trim doesn't want to bend willingly. I made a roller tool with a bolt and some donuts cut from scrap ply on the CNC.

It works so-so. The trim channel wants the walls to kink past a certain amount of bend.

I was going to make a couple of roof skin bends on the brake, but the bending brake only takes 4' wide, and I've got 5'. Curses, foiled again. I might have to improvise a brake with some boards.

I've been procrastinating finishing up the hatch weatherseal 'cuz I'm still not 100% sure how I want to do all of it. Luckily, I'm pretty darn sure how I want the sides done. So I cut out two seal carrier pieces from 1/8" AL, ground to fit the curve of the hatch skin, installed the rubber weatherstrip, and ...


also ...




Closed, it fits really good on the right side:

The hatch is about 1/8" proud of the side wall. That can be fixed pretty easily. Build up the side wall edge with some bendy strips and trim rout to a perfect fit.

The left side has a couple of problems. The hatch is way proud on the end:

and there is an area where the weatherstrip needs its height adjusted to meet the hatch.

Don't panic! It might well be that the left side fit can be improved by moving the weatherstrip carrier up/down/forward/back. I'll inspect some more and report back.

I can see the finished hatch more clearly now.

Thanks for stopping by!

[KCStudly]

Just keep working through it, the solutions will come. You have done some great work there.

[capnTelescope]

Quick update for those of you on the edge of your seats... I moved the left side weatherstrip carrier about an inch forward, and now the hatch closes much better.

100 degrees in the shade

Here's a teaser for y'all to ponder. first pic:


They come in matched pairs:


I'll need 4 sets this size, and 4 sets in a smaller size.

There's a third part that I don't have a picture of yet..

They aren't necessary for the Tear to be campable, but nice to have.

I'm going to need another sheet of 3/4" ply.

Thanks for stopping by!

[KCStudly]

My first guess at the teaser was some sort of wing or knock down table frame work, but the angles seemed wrong; so I am going with tongue box hoop frame sections. Do I win a prize?

[tony.latham]

My first guess at the teaser was some sort of wing or knock down table frame work, but the angles seemed wrong; so I am going with tongue box hoop frame sections. Do I win a prize?

Hmmmm.....

KC:

I had to re-look at 'em and the multiple leg lengths doesn't seem right for a tongue box. At least with my limited mini-brain imagination. But Brad and that damn CNC machine, who knows? I'm stumped.

I'm guessing his next build will be done with a 3-D printer. "Print Now," and shazzzzam. But, once again, this thread has my attention. It's that same mystery/thriller story telling you're using on your PCE thread. Leave a guy hanging. I'd guess I'd better take a look-see at your build and see what new twists, conflicts, and tension have been woven into your story.

Brad:

We had another fine TD adventure this week. Three nights, four days into a bit of country I hadn't seen before (and we'll be headed back there before summer is done). It was my second build's first trip –my sis and bro-in-law's new 'drop.


Fine food, fishing (big fat brookies), scenery and weather. You'll be envious to hear that I didn't even have to turn the fan on. Highs in the 80's lows in the fifties, with daytime humidities 15-20%. Didn't break a sweat. (I keep looking at your A/C unit and shaking my Idaho-head)

Tony

[capnTelescope]

BTW, RandyG, if you're still out there and not too busy Staff Sergeant-ing, I showed you the other part and gave you the answer when you came by. I'm afraid you're not elegible. The decision of the judges is final.

I am going with tongue box hoop frame sections. Do I win a prize?

That would be this:

I'm sorry, that's not the right asnwer, you don't win the prize. Next contestant, please.

We had another fine TD adventure this week.

I. Am. So. Jealous.

Here's a nue clew:
This is a prototype piece of the other part that I didn't have a pic of. It does not necessarily represent the final size or the complete configuration

4 pieces each in 2 sizes = 8 pieces.

[KCStudly]

That Tony, always sticking the knife straight in and twisting it. Cheeky. I am totally green.

Hey capn', sum ding wong. I count eleven not eight.

I'm stumped, too.

[tac422]

Fenders ?