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lɐʇuǝɯᴉɹǝdx&#4
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Discussion Starter · #21 ·
I can whip our any pipe diameter / bend radius you like, no problem. That's another benefit of the re-design I'm doing; the layout will be a lot simpler, and I won't need to custom make a new layout radius for every radius / pipe diameter combo, just one for each radius, and another for each pipe diameter, then I can mix and match. End result is I'll be doing a LOT less layout work.

How strong do you figure it needs to be? Spans over a foot would probably have some flex. Not quit as flexi as if you just cut out a 2d cross section of the pipe bend, and I'll be designing some ribs that can be glued in for extra rigidity, but still not nearly as stiff as (say) a pvc pipe of the same diameter.

Also, its looking like there's no economical way to lay out just one CLR. Instead, you'd buy a bunch of the "discs" for whatever pipe diameter you want, but they are useless on their own. Then you also pick some rings that let you assemble those up into various CLR bends. The ring set I currently have laid out covers all CLR's from 2.0" to 6.0" in .5" increments. And there's no separate cut guides, because some simple parts that clip to the modeled pipe segments (included with your discs) act as the cut guides!

So yeah, with that system I think I can keep the production time WAY down, and also offer a shitload of sizing flexibility without killing myself doing a bajilion layouts. :)
 

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moron with a hammer
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They don't necessarily need to be strong, but since the idea is to get the angles right, if they deflect too much, it kind of defeats the purpose. I wouldn't expect to hang a collector off of them or anything like that, but if they can't support their own weight, that's a problem.

Also, I didn't think about this previously, but since they're cut-your-own, I'd just assumed that they can be cut to arbitrary angles. Even if it's some work, that's kind of a necessity for what I do. That was the problem I always had with the ICE blocks, because a couple degrees make all the difference with exposed header downpipes.
 

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lɐʇuǝɯᴉɹǝdx&#4
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Discussion Starter · #23 ·
Yeah, self-supporting strength is what I'm shooting for. If you want to hang a collector off them... well, model collectors would actually be really easy to make. :)

They are cut-your-own. If you want to build with them ICEworks style, you just cut and assemble a lot of 15 degree segments (the CLR rings are pre - marked for that.)

So, here's what I've got for my second gen prototype

The entire layout set is based on inter-mixable parts on 12" square cut sheets. That way I'm never stuck cutting for too long, and people can order just the bits they need the most of.

Although this layout is by far the most complex, I'm putting it first because it contains almost all the components of the system. This is the cut for the Biltwell Builder Exhaust Pipe Kit modeling set. Two of of these cut sheets would allow you to model all the bends and a fair chunk of the straights Biltwell puts in that kit, and precisely transfer the design to your metal pipe.
Black lines are through cuts; blue and green are just surface-graved markings. If you want to build a 5" bend, you take your 5.0"clr section, thread it through some disks, glue it up, and voila. With 6 1/4" x 1/8" strips joining the disks, the structure should be fairly rigid. The fill disks below may help some on longer spans (though yuo need some room to get at the end discs).
There's also some straight stips on the sheet for making straight pipe section the same way as curves. I'm looking at cutting these from .125" acrylic, which costs about $4 a square foot if purchased in large sheets, so the $30 target price for the Biltwell kit looks realistic (even throwing in some of the fill disks).
As before, the disks are designed so they can bolt to each other at any angle, with at least 4 bolts (or more likely mini-zip ties, or whatever else you like) holding them together. Whats new here is the 'keyhole' bits; once you've marked up your model (noting the the rotational relations of the parts- there's rim markings on the disks for this) you unbolt the segments and bolt those keyholes to them. They hold your pipe EXACTLY aligned with the model, and act as a marking guide. Avoids the need for a separate marking guide.


These are the fills disks, designed to be cut from something lighter, thicker, and cheaper than the end disks and other parts on the cut above. Home depot has .157" (4mm) corrugated plastic for under $1 a square foot, would work nicely. In case its not obvious, it would be easy to make these fill disks in ANY diameter, and they would work with those same CLR / straight pipe strips in the above kit.


This is where stuff gets interesting. I did a layout that includes CLR strips for any radius you might ever likely need. Again, this same layout would work with other pipe diamaters, just by using different disks to build them up.


And here's a layout of nothing but 1.75" endcaps (and keyholes). I could do layouts like this for each pipe diameter, then people pick the diameter they want, mix those with the above CLR sheet, and boom - got all bends / all diamters covered!
 

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moron with a hammer
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It took me a minute to understand how the keyholes would work, but holy shit... that's genius. It makes accurate marking for cutoff wheel / hacksaw cuts really easy, even if you're cheating the angles a little bit. Bolt 'em up, mark them, leave the line. Couldn't be simpler.

I was going to do something really straightforward for my 2-into-1, because I really didn't want to mockup in mild steel (less for expense reasons, more for noise / I-hate-being-covered-in-cutoff-wheel-dust reasons), and I don't want to waste stainless on a complicated design that doesn't come together right, but now this has me thinking about all sorts of things...

Edited to add... I will gladly product test this thing (and pay you for the privilege) if I can score version of the last two sheets in 1.625".
 

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lɐʇuǝɯᴉɹǝdx&#4
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Discussion Starter · #25 ·
That's very easy to set up. The sheet for the CLR rings (second to last) doesn't need any changes, and I can make the change to 1.625" diam on that last sheet in under an hour. Was planning on doing some cuts this weekend. How's $7.50 a sheet for those two sound for 'product tester' pricing? Will let yah know on shipping (probably a flat rate box or envelope). I'll throw in a free fill to match any pipe diam ordered at a 'buy two, get one' price, since I'l like to see those tested.

If yah take some good pictures, I'd be willing to provide more product in exchange; I really need shots of these built up / used as cut guides to get the idea across.
 

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moron with a hammer
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Good by me. Guess it's about time to put my mockup motor together.

Let me know when you get things hammered out on your end, I'll send you some funds, and we can get this underway...
 

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lɐʇuǝɯᴉɹǝdx&#4
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Discussion Starter · #29 ·
Been a while but I've been doing occasional work. Here's what I've got now. No trick photography - that is standing under its own support, not even touching the wall behind it.





Acrylic wasn't a good material choice, it turns out. Really limited the choice of glues and drove up drying times. The glues that did work tended to crack when you flexed the model. Was gonna go back to 1/8 masonite, then I tried using this new material (1/8 inch Luan plywood) for a whole different project where I wanted some pretty looking wood. Turns out it cuts SUPPER easy (100% power at 90% speed, so just about as fast as the machine can go) and is light and stiff. Just what I needed.

Assembling these things is a bit of a pita (so much gluing), but the finished assembly is pretty sturdy, easily supporting its own weight even just by gripping one of the end discs (or bolting it to a manifold plate).

May need to experiment a bit with bolts - the ones I bought had large enough heads that certain rotations (just about anything other than 90 deg increments) didn't work.



Some smaller screws worked OK at 45 degrees, which is (in terms of space for the bolt head) the worst case scenario, so I'm sure I can sort that out, but may want to change the design slightly.



The ends of these were supposed to be easier to position, via a single bolt in the center, but that didn't work out so well. I've got a solution for that though- yeah bitch, MAGNETS!
 

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lɐʇuǝɯᴉɹǝdx&#4
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Discussion Starter · #32 ·
Thats insane. Looks like it took a lot of work to make.
It took a lot of work to nail down the cut layout for a functional design, but that's just doodling on the computer. Laser cuts all that (plus some stuff I didn't use) in about 15 minutes. Parts glue up in a couple stages, don't know how long really because I did that watching videos. Its fiddly, but the glue I use (Loctite GO2) has a really easy dispenser. That's one big reason I ditched acrylics- the glues are messy, and require very clean, tight joints. With wood I just sqeeze dat shit on like mustard.

Check radio shack for small round magnet. Cheap enough and I know the work very well on r/c airplanes.
I've got a stack of 300 5/16" x .125" rare earths coming in the mail, paid about $.10 a piece off ebay, direct from China with free shipping. Got them for another project, don't plan on using them there. Should be perfect for this, except the center holes in my current layout is 1/4", not 5/16". Not hard to change though, and the layout has room for it.
 
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