Bullet Tear

[GPW]

Laura, Exactly ... hopefully the math wouldn’t be too complicated , more like a drawing an arc to the correct radius and measuring ..

[Mary C]

See yall just go to too much trouble I use a hammer to drive the nail in and a string attached to the nail and a pencil on the other end then just make the circle and then cut in half and ya got it. I don't worry about the math just cut the string so it will go in half. Course my brother asked if i used pie but I tole him I ate it. I knowed it was peanut butter and chocolate. I still am not sure about the arc on mine I just drew it and applied the blade. sometimes it is not worth all the hours trying to figure out all the math I coulda had it cut by then. You gotta know when to wing it. I was taught that by a mechanical engineer who was a perfectionist but used the string because it was faster and just as accurate in the long run. Note I didn't mention names in regard to the Width vs height but since we don't know where she is from and I am sure .......Doesn't the wind blow everywhere on occasion then we will assume that it does apply to everyone.

seriously I know that it could be done and what were you talking about backer on the foam??? I am confused about that,,,,I know it doesn't take much.........

Mary C.

[lthomas987]

When I wanted curves for the little bike trailer I am working on I used two screws and a yardstick. I ran them both through the yardstick with the radius I wanted beween them, then sunk one in the foam a bit and used the other to etch the curve.

But if a person, say like Juan and C5 shark, really wanted to build a half dome out of foam it could be done out of flat sheets if you knew the angle you needed to set your saw blade at and the diameters of the circles involved to get the right rings. Really with very very little waste. A hot wire jigsaw like thing would be really helpful. Especially you could tilt the table to cut at the angle you needed, and since I'm not a steady hand I might set a pivot in my foam which would require a bigger table.. but probably worth it.

Now I want to do that. Dang it! This guy is doing it with hardwood and making a bowl. But the concept would be largely the same with foam. http://bobhamswwing.com/Articles/economy/TRUE%20ECONOMY.htm

If you want a 60" wide half-circle you could cut it out of 4x8 foam. I'd want to cut it from a sheet of the thickest foam I could find which is 4" to reduce the number of rings. 24" tall in 2" foam would require cutting 12 rings. 3" foam would take 8 rings. 4" foam only 6.

[Mary C]

Laura I think I scared him off, I guess I was a little hard on him but I really think it could be done and am excited about another build. . I have been working on mine and and got an interesting idea then came in and you had described it. I will go back and work..........
Mary C.

[Catherine+twins]

KC, I think Catherine’s incident was a turning point for all of us , when the Foamie part survived so well .. and the Steel was the part that was bent ... Up till then , no one really knew about Foamie’ durability ... An unfortunate and precautionary tale , but a confirmation of the structure and concept ... For which we are grateful !

Let me take a moment to admit that the teardrop-curved roof on Penguino1 wasn't done with 2-inch foam and kerfs. I actually used 3/4 inch foam for the roof, making the rash leap of faith that the curve and the skin would strengthen the thinner foam. (It did have pine 1x1 ribs. The new one has a flat 2-inch foam roof and no ribs.) And as noted, the foam box survived fine, even with the thinner foam. Bending it was tedious (mostly using the weight of the foam itself, three sheets spliced along the long side since my cabin was 5 ft wide) , but leaving the plastic skin on the outside of the curve made all the difference! Once the GG was dry I stripped the plastic off and skinned with canvas.

All of which is to say, I think the OP's front curve could be done with 3/4-foam, butted up to a thicker foam on the walls. If extra strength is wanted or needed, a second layer of the 3/4-in foam could be curved over the first.

Catherine

p.s. My trailer is on backorder! But the week of April 4 is my kids' spring break, so assuming the trailer gets here we will be screwing and gluing up a storm!

[grantstew8]

These were some ideas I was kicking around for version II which I've abandoned for the time being.
If you number them from the left to right 1,2,3 and 4.
2 was my favorite a basic boat hull shape with gull wing doors to get in and a rear hatch.
1 and 3 had some merits similar to 2.
4 where the central lid would lift up like tailgate of a hatchback but though it was impractical to build and use.

Just ideas for the pot.....

[GPW]

Grant , all Great ideas (aesthetically) , and very workable , but such things as gull wing doors , tailgates and hatchbacks do make things problematic to construct and seal ... practices we’ve long abandoned in favor of overhangs and simple standard doors on the rear (Much easier, and more practical in the long run ) ... And a small (easy to install ) side cargo door wouldn’t be a bad idea , used as a loading hatch , emergency door , or a spot for the AC unit ... No reason it can’t be a bullet and still be practical , and fairly easy to construct ... I offer the FoamStream as an example ... That worked out just Fine !!! Did it all by myself ...

The inverted Boat does seem to be a Very Good shape for trailer cabins .... It works in water eh , and likely similar in the thinner fluid atmosphere... A shape I’m working on with the Zephyr , the next Foamie’ build ... just an inverted flatboat ... sorta’ ... SIMPLE , yet streamline, easy to make ... like a boat ...

[juanrc24]

Gull-wing doors I like that idea!

[grantstew8]

For version 4, this was my idea of how it opened. A little like a 1970 sci-fi pod.
Thanks for all the positive feedback

[C5shark]

Catherine hasn't scared me off, I've just been busy with other things. I like the ideas! I've drawn up a few other ideas, which should be a little simpler to build than what I had posted up before (especially for a fine time build) and easy enough to fit a reasonable side door.

I'll post the latest sketch I'm favoring when I get home from work, but I designed it around the idea that the TV is blocking air on the lower portion of the trailer and went with two simple curves for the roof. Because I'm not planning to have a galley, it's hatchless and I've been playing around with the idea of semi-truck style "trailer tails", which if the airflow will stay attached to the body, should help reduce the size of the low pressure zone (drag) behind the trailer.

The one good thing about building light is that if it's too light and stability suffers, it's easy enough to just add beer for ballast!

[juanrc24]

In floor kegerator!?

[twinight]

For version 4, this was my idea of how it opened. A little like a 1970 sci-fi pod.
Thanks for all the positive feedback

There was a F117 themed teardrop that was at Lake Perris gathering over the weekend. It had a cockpit hatch opening much like the rendering. I'll post up some pictures tonight.

[GPW]

What if it’s raining ???

[C5shark]

What I might end up going with, sticking to similar dimensions, it's 5x8x4. The tail section is 24" long and would be an add-on, I'm thinking it could be hinged and folding.

[GPW]

Just saying , if you round over the edges it will Look more “bullet” even if not exactly round ...