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

[capnTelescope]

How will you join the side gutters to the top section?

(rant)
This is the kind of question I like, because it provokes thought, instead of worry.
(/rant)

Let's look at the picture:


Here we see the top gutter actually meeting the side gutter, although there is a difference in altitude that needs to be fixed. No big deal. BUT, I'd like to radius that intersection so I don't have to cut the weatherstrip at the corner, lest some vortex form and ruin everything. The side gutter is also a mockup, so we can do whatever is necessary to join up to it. (It's missing the inner wall/side here, which is also negotiable.)

I have a few half-baked ideas about how to do that radius:
1. I could fabricate a corner block with the required radiused 1/2" high x 1/4" thick stickin'-up-thing for the weatherstrip to go onto around the corner.
2. I could make a gutter across the top that has the corners and the stickin'-up-thing built in. Material could be wood, aluminum or glass/epoxy or some combo thereof or... something else. Wood might not be too good, as there are a lot of thin cross sections. It would/could be CNC machined, of course.
3. I could make a casting pattern, and cast it out of empty beer cans and used alum foil.
4. Actually, the 2 pieces of aluminum angle that I used to get something to look at isn't all that bad an idea for the top gutter. The width of the gutter can be made to suit. Some kind of goop can seal the seam and the join to the corner blocks. I would use thicker stock than the 1/16" HD had.

No idea is too weird if it can be built. Anything goes. Don't forget that CNC is available.
Any suggestions, anyone? Bueler?

P.S. The weatherstrip is soft and squishable, so not to worry about that. We just have to get it to the right place and height.

[GuitarPhotog]

I'm enjoying watching your process here. It's both enjoyable and educational. One of your comments rang my bell "Give the water somewhere else to go"

My teardrop, built in 1948 relies on channels to collect the water at the top of the galley opening and drain it down the sides to the ground. It works very well, but has one drawback. All that water on the ground at your feet is a major PITA. I use a piece of indoor/outdoor carpet on the ground in back of the galley, and it becomes completely saturated after just an hour or two of rain. I'm considering building removable "rain gutter" channels to route the water off to the side and out from under foot.

My hatch does not leak water into the galley under any circumstances, including freeway speed in a downpour, and does not rely on rubber gaskets. The hatch has a set of interlocking channels that fit with the drain channels to keep water out when the hatch is closed. However it does nothing to keep dust out of the galley, and an hour on a dirt road will fill the galley with so much dust that every plate, pot, and spoon has to be washed before use.

My $0.02 worth

<Chas>

[capnTelescope]

Hi, Chas. Great post.

All that water on the ground at your feet is a major PITA.

Hmmm. Hadn't thought of that one. I'm glad you brought it up. Sounds like the carpet is the problem. Holey doormat? wood slats? This goes on my shopping list.

All this worry about rain, and I'm in dry Texas after years of living in SoCal, where it's desert. 30" and 15" per year average, respectively.

Bummer that the dust gets in. I can identify with that. Otherwise, that '48 must be a pretty good design.

Your $0.02 was well worth it. I'll owe it to you.

[KCStudly]

Message received on the doom and gloom. It is a character flaw of mine; I appreciate your patience.

On the gutter transition, I assume that welding is less desirable option, but I wonder if there is a way to leave the gutters squared up to each other, run the top one long so that it caps the tops of the side ones, then drill a hole in the rear face of the top gutter that feeds into the sides. The seal could transition off of the gutter on to a radius piece that cuts across the corner, so long as everything between the seal and the gutter is sealed up well and it all drains into the gutters.

Another option is, if you come up with a corner piece that is not to difficult to fab, I might be able to scrounge something up and get Karl to weld it for you. I'm thinking angle stock coped to fit a 90 deg outside corner, a piece of flat bar rolled to the vertical inside radius, and a flat piece to fill in the floor. I'd be willing to help you out on something like that... it's in my wheelhouse of skills. Wouldn't be too hard to feed the top gutter into these corner pieces with some rivets and gutter sealant.

[capnTelescope]

Thanks, KC. Now you're thinking!

I appreciate your patience.

No worries. I know you've got my back, here. I appreciate that.

On the gutter transition, I assume that welding is less desirable option...

That is correct. I don't have a welder, or any welding experience. I keep looking at the jr. college courses, buts that's down in Austin (20 mi.) at rush hours. I am proficient with JBWeld. And light pop-riveting.

I wonder if there is a way to leave the gutters squared up to each other...

Let's look at the picture:

It doesn't show real well, but 3.1 has a support shelf for the gutter cut into the hinge block. That will locate the gutter on the front-back axis and square it to the left-right axis. The left-right axis doesn't currently have a stopper, but that might be a good thing?

Here's a Paint closeup, just to make it clearer:

I didn't bring the gutter wall up high enough to get in the picture, but it's (currently) 1/4 ply coming up 1/2" above the gutter bottom.

BTW, I'm seriously considering reordering weatherstrip with 1/8 " grabber. Might save $$ over 1/4 material. Also, "wetted" wood will get epoxy in some form.

Think upon that for a bit.

[capnTelescope]

I was out tinkering in the shop today and had another successful failure.

I thought that if I did something like this:

and applied a pipe clamp, I might get something useful. No. And yes!

Not much use for this:

But I took it to the Hatch Lab anyway.

And ended up with this:


Crude, but maybe it'll help some of you see the upper transition. More importantly, a great discovery was made in the traditional way -- by accident. Notice how the two pieces of angle are not parallel. You really can't tell from the picture, you had to be there, but the bottom piece of angle is creating a downhill slope from the centerline of the hatch. I noticed this while I was trying to piece this together, and said to myself, "Self, this is one more reason to like the two-angle design." This gives the water a reason to go where I want it to go. Ommmmmmm.

Comments and suggestions are always welcome. Thanks for stopping by!

[capnTelescope]

Oops, almost forgot...

Here's a top(ish) view of the above:


And, last but not least, first backyard bluebonnet bloom of the year!


Happy spring!

[KCStudly]

How about something like this for the corners?



One as shown, one opposite hand.

The 1/2 inch tangents in the throats would allow for riveting the top gutter on and whatever transition you want to do for the sides. Notice that the top throat is wider to allow the sloped lower half of your top gutter to be wider at each end

I think maybe I, and perhaps others are getting confused about the side gutters because you are not showing an inner wall, and there is a gap between the top gutter mockup and the side walls.

So to be clear, you do not plan to form aluminum side gutters but do plan to line wooden side gutters with epoxy, or some such super duper sealant.

I would be happy to contribute to your build by fabricating the shown gutters; just let me know what you want for dimensions keeping in mind stock flat bar sizes for the sides. These would be made from sawed flat stock for the bottom and formed flat bar for the walls welded on the outside corners. It is very likely that the material for these can be scrounged, at no cost.

The outside radius could also be squared off, if you prefer.

If you would rather form these yourself, you could make a wooden buck (on the CNC, of course), use dead soft 1000 series or 3003 alloy aluminum sheet and hammer form them over the buck, then trim the excess edges flush to the surface of the buck with a sanding disc. It is really not that difficult to do as long as the tooling for the buck is solid. Here's an example. Essentially it would be a piece of hardwood or good ply the shape of the inside of the trough with another piece bolted to the back side that acts like a clamp, keeps the work piece in place, keeps the back from warping while the edges are hammered over, and keeps you from accidentally hitting the back with the hammer. Since you don't want holes in the piece from where the clamp bolts go (and can't weld them shut after the fact), you would have to make the piece a little oversize, putting the clamp bolts thru the sandwich at the edges, then trim the excess areas with the holes off after.

[capnTelescope]

I think maybe I, and perhaps others are getting confused about the side gutters because you are not showing an inner wall, and there is a gap between the top gutter mockup and the side walls.

Agreed. I've felt frustrated because none of the pictures showed all this clearly, causing me to have to give these wordy descriptions and ass-u-me anyone could understand. So I took on this mission, and made clear?, annotated, color coded pictures to show all the major parts (I hope).

Black = side gutter inside wall
Blue tape = side gutter bottom


Rear view, looking forward


Top view from left side

Why didn't I think of this sooner?

[capnTelescope]

Meanwhile, back at KC's post...

How about something like this for the corners?

That's what I'm talking about. I'll need to check dimensions.

So to be clear, you do not plan to form aluminum side gutters but do plan to line wooden side gutters with epoxy, or some such super duper sealant.

Uhmmmm. That was the original plan. The more I work on this, the more inclined I am to think I want machined aluminum for the side gutter inner walls. .06 thickness, not the .25 I mentioned earlier, cuz HD 1/4 inch ply is ap-cray, and another sheet of 1/4 marine ply is $50. I'll CNC those (I hope). Super duper sealant on wetted wood and steel, and where wetted parts join.

The outside radius could also be squared off, if you prefer.

If you mean the top/upper/forward edge by the hatch spar and the outer edge by the upper galley frame, yes I prefer a square corner there.

If you would rather form these yourself, you could make a wooden buck...

That would be fun to try. Besides my doc says I need to get me 15 minutes of exercise a day. Hammering would count. I'll give it a try, which would avoid confusion or getting people annoyed if I change a dimension. If it turns out to be a fail, I'll come begging.

I would be happy to contribute to your build by fabricating the shown gutters...

I truly appreciate the offer, KC. For now, I'll try hammering them out on a buck. Let's see how that turns out. Might be worth making a vid.

[KCStudly]

Sweet! I'm looking forward to your success, and it is always rewarding to say that you made it yourself!

[capnTelescope]

Following KC's link to pounding metal, I SWAG-ed out a buck for my corner gutter blocks (gutter corner blocks?). Ran down to the Blue Box this time, and came home the proud owner of a small piece of 26ga soft aluminum sheet. Cut the bucks on the CNC, and made an attempt to cut my chosen sheet shape on the CNC.

I need to find a suitable cutting fluid for aluminum, as the cutting edge of the router bit got gunked up with a glob of Al. Also, the cutting conditions weren't right. I think I need to keep the rpms low and get the feedrate up to encourage good chip formation. Light depth of cut, too. I'll eventually get this right, as I will be cutting stiffeners for my hatch ribs from Al. Maybe use the 1/8" bit, to keep the surface feet per minute low.

Then I proceeded to beat the heck out of my new aluminum.

This turned out about as I expected, with a tear in the middle of the 3" radius. Since I expected it, I shed no tear for the tear. Actually, I was quite pleased with the result. Not bad for a beginner, I thought.

Here it is:


The setup:


Another small crack:


Into the Hatch Lab. It goes here:

The top end is too wide to fit through Hatch Spar 3.1, but 3.2 will be better.

And it fits well in the side gutter!


The bucks:


I also picked up a strip of 1/16" flat bar that could be epoxied in the radius, so no scrap part yet.

Thanks for stopping by.

[paulnb57]

Why not use aluminium for the straight sections and form the transitions from lead roof flashing, which is soft and easily formed?

Just a thought....

Paul

[mikeschn]

Brad,

You're doing a better job than me. Back in 2003 when I was cutting the aluminum for my sides, I laid the plywood on top of the aluminum, and used a router bit with a guide bearing.

Instead of a nice clean cut, the router bit ended up getting clogged up and wouldn't cut.

I had to get out the jig saw to cut the aluminum.



They say it's possible to cut aluminum with a router. But you have to slow it way down. Good luck with that!

Mike...

[capnTelescope]

Why not use aluminium for the straight sections and form the transitions from lead roof flashing, which is soft and easily formed?

My first thought was, "Brilliant!" My second thought was, "I don't even know if it's available." Everyone is so scared of lead that I didn't even think of it. You can't hardly find it for any purpose. Great idea! I'll have to look. I'm not afraid. Thanks, Paul

They say it's possible to cut aluminum with a router. But you have to slow it way down. Good luck with that!

.
Thanks, Mike. It's good to see you're still following the build. The 1/8" bit will reduce the cutting speed by half from the 1/4. Just try to find one with a guide bushing, though. Maybe that'll help. I'll report any successful results here.