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Re: Mike's Build Log

Posted: Tue Jul 25, 2017 6:17 am
by Nick
Hi Mark,

yes its really only just Mikes experiments with PLA which prompted me ref the possibility of printing a high(er)temp model. Here are the details for the resin ... 6a28c805e0
I have a Printer like this one ( its precursor - a smaller one) ... 6a28c805e0

I used the resin this year to cast a bronze figure for a mate who has a Bronze Sword casting workshop and we found its incredibly temp resistant - like 730-800c for over an hour in a furnace and it still didn't melt- we had to use an air line to "oxy" burn it out in the end!
I also thought I might use it for small plastic injection moulds because those temps are trivial compared to that of the furnace but haven't had the opportunity to try it yet.
I have no idea how it will react to pressures though.


Re: Mike's Build Log

Posted: Tue Jul 25, 2017 1:33 pm
by Mark
Thanks for that information Nick. I was trying to figure out what chemicals remain or break down to, say after you raised the temperature to a high heat - this one for example that's used in the PHOTOCENTRIC 3D RESIN (HARD) formula if that's the one you used. (BISPHENOL A ETHOXYLATE DIMETHACRYLATE) The safety data sheet mentioned this but without numbers. "Melting point/rangeĀ°C: No data available" I don't think acrylates are stable at high heat and just out of curiosity wonder what they turn into when you bake them at say 600 C. You mentioned 800 C as a limit. I recall reading some other high temp printing material that have organic molecules that turn/decompose into a very hard carbide when baked. I don't think anything is going to beat quartz. The clear melt aluminum oxide crucibles/ruby-sapphire are very expensive and can take a higher heat than quartz but when using them you have to walk the temperature up slowly because they can crack. Carbides crucibles too I think.
Anyway I don't know why they can't formulate something like a Thermosteel printer. It's just a mix of steel fines and sodium silicate I believe and rated at 1300 C. Or something like the aluminum oxide/silicon oxide slip they make spark plugs out of with a fairly low coefficient of thermal expansion, ... 20MSDS.pdf

Tiny objects/humble beginnings I posted this awhile back. ... ssible.php

Maybe you could print a small jam jar jet and see how that goes if you like those. I want to build a Klein bottle jam jar jet snorkeler. There're a couple of shapes I think might have a good chance of running. But by whatever means there's no free lunch, each method has its drawbacks. But printing you can make perfectly curved tubing easily I guess. The other day I was watching how tubas were made and one smaller part they pushed several ball bearings through the U-bend tubing to align the shape.
Imagine a Klein bottle jam jar jet snorkeler powering a toy plane or little boat for example.
I saw this make believe fanciful drawing that looks like steampunk art but the concept of a Klein bottle as an engine is there. ... 00/k22.jpg
Klein bottle candle ... -521166077

Re: Mike's Build Log

Posted: Tue Jul 25, 2017 3:10 pm
by Nick
Hi Mark, yes as soon as I get a window I'll try a simple Jam Jar - Just to see how the Resin performs. I have some if the "hard " resin but I also have a bottle of the "casting" resin which is the high heat one which I'll use for the jam jar.
If it works then it certainly opens up a lot of new possibilities!

Re: Mike's Build Log

Posted: Tue Jul 25, 2017 5:42 pm
by Nick
This is the castable resin ... cba1185463
I'd better get on with the cad!


Re: Mike's Build Log

Posted: Tue Jul 25, 2017 10:11 pm
by Mark
That's the spirit Nick. Be the first on your block or maybe the world to print a jam jar jet. Today I snorkeled up two Budweiser beer bottles, one ran the other not so well. So I set them side by side and noticed just an ever so slight difference in height where the neck forms and curve of the shoulder. One was a Bud LIght like on the far right and the other a regular Bud like on the far left. It's insane how such a little difference affects these things. When I open this link in a new window or tab the photo of the bottles is much larger than just clicking on the link. ... 408_tp.jpg

Also after about 5 seconds the "long" running one flamed out with lots of smoke from the lacquer coating on the inside of the bottle. I decided if you are going to use aluminum bottles or cans expect a lot of smoke. I don't like smoke. One thing nice about the paintball tanks maybe being thick they can absorb and transfer a lot of heat whereas a steel can which doesn't conduct heat nearly as fast might have a much faster rise in temperature for the vessel, the immediate area where the fuel and combustion take place, whether that's good or bad depending on the size of the engine or other factors. I have a steel paintball tank that starts up and runs fine but it gives out faster than the aluminum ones. Maybe the methanol starts to boil sooner in the steel bottle making the mixture too rich? I have two large high pressure gas cylinders that are ultra thick steel and they run like a bat of hell in cool weather, ear muff time. And as hot as they get, they tolerate high temperatures lasting 3 to 5 minutes without water cooling and whatever fluctuations in the fuel/air ratio with the rise in heat. Maybe in some cases you could say larger ones are more forgiving or idiot proof. It's hard to draw absolute conclusions, I'll say that.
The larger guys

I happened to see this when searching for the high pressure gas cylinder tanks Mike, it's the sound augmenter that cranks out the noise when used with the little paintball tanks, that shape makes a terrible sound. It will wake the dead.

Re: Mike's Build Log

Posted: Wed Jul 26, 2017 2:08 pm
by Mark
Random thoughts

On the topic of baffles, say to keep the fuel at the bottom if spinning a jar or just to keep it from flying all about dampening feedback, you'd have to be careful because any obstruction has the potential to throw things out of whack. If you get really energetic combustion the pool of fuel is going to be like the sea in a hurricane, but a well designed baffle could boost performance and maybe add some stiffness if a can is flexing. Having a stiff jam jar with nothing to slow the flame front seems the way to go, but keep in mind the smallest misplaced obstructions or change to the system might create chaos or some unfavorable eddy currents. I remember putting aluminum flashing and shim stock along the walls of a glass jar to lessen the heat and it really didn't like that. Also it's been my experience when snorkeling they do not like flares at the intake but can transition wider where they meet the combustion chamber. And if you get an hourglass wide/narrow/wide snorkel motif to run you let me know. With all my plumbing pipe tinker toys nothing along those lines worked for me. I think for jam jar snorkelers you just want a good piston effect and any attempt to gain in one direction you pay for in the other.

The thing about jam jars, the transition to the outside air is really tortuous. For a snorkeler, an interior glassy smooth surface might have a beneficial effect being faster, smoother air flow, more so with smaller jets. Some of my crude plumbing pipe snorkels are pretty bumpy inside, but it's not inconceivable that a slower snorkel might better match a more stable combustion. When you start going fast little defects sometimes matter.

It occurred to me that when I lean the paintball tanks about a 30 degree angle, aside that there may be more surface area of fuel presented to the traveling flame front or the fuel might have more cooling properties, but it may also be that the flame front now has a more solid uniform bottom flat surface to reflect off of.

I sometimes revisit/wonder if a quarter wave straight tube would be a viable thing to try. Again, the old joke, I think the shape would be easy to design. ha
One could try a bang start to get the feedback started but most likely unless you're feeding in high test fuel like hydrogen or acetylene or say fuel pump spraying methanol and oxygen into a chamber, which qualifies as something known as a chuffing rocket, where real rockets sometimes take on this effect just before exploding, it's going to be a difficult pipe dream to realize, but I want to think it's possible. There's that chemistry experiment called the barking dog where the quarter wave pipe barks like a dog, and it'd really razzle the chemistry crowd if you came up with an honest to goodness incessant barking dog. Maybe a straight tube segment within a straight tube would channel/highway the air so that it could breathe.

Sometimes I think about this and wonder if it's a shallow depth fast flame/low confinement acetylene "jam jar snorkeler". When it flames out, you see a rather yellow flame. I used to run my Logan on acetylene and the soot when it flames out is spectacular from incomplete burning. I don't want the complexity of compressed fuels and fuel lines but whatever it is Leo made, it's food for thought.

Re: Mike's Build Log

Posted: Thu Jul 27, 2017 1:16 pm
by Mark
Tidbits or a crumb or two maybe of some use.
So an update on another snorkeler attempt, a two dollar vase I had bought awhile back because it had a snorkel. It has a gradually flared exhaust and will at least run for a few second poorly. I then drilled the neck out a bit more and saw that it suffers from the same thing the new 12 ounce paintball tanks have, some rough jagged internal edges where the aluminum didn't mold uniformly. In the past, I had tried plumbing pipe bell flares, other odd end piece flare segments I had lying around, and then some dapping punches to flare the end of some aluminum tubing snorkels and got slaughtered on the battlefield time after time. But maybe a longer gradual funnel flare would be something to try if you can construct it, I don't know.
The item on the left in the photo below is a hollow aluminum baseball bat with the handle cut off of. It doesn't work perhaps because the inflow can't get out of it's own way/separate enough to entrain and swirl the air. Maybe a fatter bat with a more rapid transition ...

The vase being cigar shaped reminded me of some tuned exhausts and this article.

"The tube shapes which will resonate seem almost infinite (although it is hard to believe at times) if all other factors concerned are proper. There are a few conditions , however, which will not support resonance. One of the tube shapes which will not function either in theory or in practice is a cigar or aerodynamic shape. The critical portion of this shape is the exhaust end. The extreme tail end cannot be converging because a condenstion wave will not be reflected as a rarefaction wave from the open end of the tube, and consequently the valves will not open." I should say the vase snorkeler/snorkelette sounds about like a jam jar running, not slow but not louder like a good snorkeler and it dies out after maybe 5 seconds.

The Budweiser snorkeler is promising as a cheapo build if I could come up with a way to swage the neck to a light aluminum tube snorkel. When mounting a snorkel to the bottom of the bottle it runs but not nearly as robustly, perhaps a necking transition to some degree is a better route for a snorkeler. Or the corked necked end of bottle now being the bottom doesn't reflect the flame front and is dampening the energy. Using the bottom for the top as in something like this arrangement but with an optimized snorkel.

There are these towel rings that are often aluminum that might be useful for a downward U-bend thrust reverser snorkeler. Would be nice to find a source for tighter/shorter length perfectly uniform 180 aluminum bends rather than these longer gradual radius bends. ... lsrc=aw.ds

Re: Mike's Build Log

Posted: Fri Jul 28, 2017 8:19 pm
by Mark
"Your item was delivered in or at the mailbox at 2:07 pm on July 26, 2017 in GOLETA, CA 93117." Just wondering if my package made it to you at work?

Re: Mike's Build Log

Posted: Fri Jul 28, 2017 8:33 pm
by Mike Everman
Fan mail from some flounder?

The famous resonanttheme snorkelers are in the hizouse! But I can't play with them until the 7th! ... 6.jpg?dl=0

Re: Mike's Build Log

Posted: Fri Jul 28, 2017 11:15 pm
by Mark
That looks like them. Last night I was playing with a 12 ouncer paintball tank clamped in a vise at about a 30 degree angle with ~50 ml of methanol making cavitating sounds by forming a circle with my thumb and middle finger in the exhaust stream when it was it was windy, cloudy, and unstable weather outside, an occasion where it was cool enough to run it. Today I was trying to start my favorite tiny 4 ounce jam jar in a miniature desktop spin device and it won't even run when it's hot and humid out!!!
I made a video of the 12 ouncer last night on the porch but the sound just doesn't get captured on video and it looked foolish somehow the rapidity in which I was exaggerating a sudden open and closed hand movement without the real sound to back me up. And the same when I used a 1/2 to 1 inch bell reducer in the exhaust stream, which was louder. But it made the dog bark two houses down, he listens to my experiments. ha
If you could hear the snorkelers in cool dry air they aren't fussy in the least and really ramp up when you light them. If you had a proportionally sized small hot air balloon, something like piglet snorkeler would probably throw enough hot air in a few minutes to lift off or probably even smaller snorkelers or jam jars by some design with smaller balloons or some kind of chimera of ultralight helium blimp and your jam jar propeller craft concept of some sort.

Anyway I'm glad you'll get to start them up and hear the snappy little snorkelers firsthand. Happy inventing!

Re: Mike's Build Log

Posted: Sat Jul 29, 2017 1:25 pm
by Mark
A few other characteristics of the little snorkelers that's like jam jar jets is that if pouring alcohol into the snorkel with the funnel and you spill some on the threads at the tip of the exhaust, it's just like a jam jar lid with a few drops of alcohol on the top of the lid and it doesn't sustain when you go to light it. Similarly, if you linger with the lighter flame when you go to start it, snorkelers will draw in some of the flame gases or interfere and that too will sometimes give you a false start. Instead of a lighter if you do these experiments often, maybe a simple now at $1.87 with 5 cents shipping from Hong Kong ignition put into a PVC tube with battery and prongs with push button start would be better and more cushy. You could use the bare minimum voltage to be quieter and hopefully less than a second of spark would do it. Might make snorkeling more fun, that and a simple way to air them out if you don't want to use a bulky air compressor. ... SweW5VZ~zR
Some of these types of units fire more slowly and are only loud if you gap them wider but cost a few dollars more for the wider gap action I guess.

In other news I was spinning a 12 inch rubber band propeller mounted to a stick like a child's toy and thought/wild guess it'd probably have to spin 10 to 15 times a second to make enough lift for a very light craft, if there was a way to gear it or make it spin that many times to one rev of a jam jar. Also it seems pretty easy to put your eye out with the one I have but it does fly nicely.

The latest kluge just trying to get ideas. Materials science gathering is an important part, finding simple shapes that work together.

Re: Mike's Build Log

Posted: Sat Jul 29, 2017 3:39 pm
by Mike Everman
Ha, dude, I love that picture. I see you've taken over the dining room table.
It's the "where's waldo" of pulsating combustion.
Thanks again for the toy loan. Going fishing for the week at 9,600 feet or I'd bring them along!

Re: Mike's Build Log

Posted: Sat Jul 29, 2017 9:07 pm
by Mark
One day it would be interesting just to see what jam jars do at high altitudes or how the parameters change. Fishing and nature sound nice. No hurry on the snorkelers. Have a good trip!

Re: Mike's Build Log

Posted: Sun Jul 30, 2017 6:42 am
by Nick
Mike Everman wrote:Ha, dude, I love that picture. I see you've taken over the dining room table.
It's the "where's waldo" of pulsating combustion.
Thanks again for the toy loan. Going fishing for the week at 9,600 feet or I'd bring them along!
Enjoy the Fishing Mike!

Mark - My new Mill arrives at 9am tomorrow so I will be busy getting that settled in - I'm going to be busy with that for a while but I haven't forgotten the 3d printer project :D

Re: Mike's Build Log

Posted: Sun Jul 30, 2017 4:07 pm
by Mark
Well it would have been funny to see a man with a fly rod pulling a jam jar snorkeler catch out of his wicker fishing creel. Probably high altitudes would lower the performance of jam jars, and methanol's boiling point lowered ~1/6 in temperature. But who knows for sure what behaviors would appear until it was tried - maybe something unusual or unexpected that could be exploited or merely to observe how flame fronts travel in rarefied air in a jam jar or whoosh bottle? In space without convection fire forms a sphere and often extinguishes itself. I sometimes wonder what it would take to or how to design an idealized space jam jar jet. It wouldn't hurt to run a tiny 100% ethanol jam jar for a few seconds in the space station, to stimulate a curiosity in science and all. Imagine one flying jetting about in weightlessness through the cabin, the astronauts having a bit of fun. Even something this size would be fun to try. It wouldn't need to burn but a tiny amount of ethanol. ethanol being more compatible than methanol for spacemen.
"Normal air pressure on the ISS is 101.3 kPa (14.7 psi); the same as at sea level on Earth. An Earth-like atmosphere offers benefits for crew comfort, and is much safer than a pure oxygen atmosphere, because of the increased risk of a fire such as that responsible for the deaths of the Apollo 1 crew."

Nick, what are you planning to make with your new machine? Are you milling about with some ideas for a combustion device? I'm looking forward to your printing project.

In the past I had bought some 190 proof ethanol from another state and had it shipped to Florida which is legal but Florida doesn't sell any alcoholic liquor above 151. I just wanted it for some jam jar testing. And on Sundays you have to wait until 1 pm before any alcohol is sold but as it so happened on a Sunday where I knew I could by some beer earlier at the large package store on base (the base has different rules, they open at 8 am), I stopped in to buy some beer and noticed the base also sell 190 proof spirits! This Clear Spring was a few dollars cheaper than the Everclear, coming in at $12.99 and no tax which is nice. If you put a single drop on your tongue, it feels like pure evaporation, a very strange sensation.

Anyway a few more shapes among the spirits. In the forefront and you can't see the transition, a cut in half Bud Light bottle with the metal ring at the top cut off and a flared section of aluminum tubing pulled through from the inside of the bottle and it snugs up nicely against the neck. It's a way to connect a piece of1 inch tubing to a bottle but in this case it's too wide of a piece of tubing, not enough confinement or mismatch ratio of snorkel diameter to combustion chamber volume. You then could sleeve over the top bottle section with a bottom part of a bottle to make the Bud bottle whole again. The very light aluminum tube snorkel/shower curtain rod(?) segment is the one behind the eye-dropper, connecting to the beer can, like some extendable fishing rod/telescoping philosophy I suppose. It was just a short segment of aluminum tubing to test or match the fit to the bottle neck. Next to it I cut off the top neck of a Bud bottle and stuffed/inverted the cut off top segment back inside the can but as of yet no ideas for it. It made the top part stiff again instead of wobbly.
Recall you can make a lot of variations.
Rolled edge

I was watching a video on making a device to observe the upcoming eclipse using a Pringles can and it occurred to me the aluminized paper walls of the can and steel bottom, much like a can of Planter's Peanuts, the long tube might be useful for a quick, short running/short lived Pringles Snorkeler. (Another Pringles life hack)

PS There's also a poppy capsule in the photo, I was trying to be the first on my block to get one to jam jar, like my little plastic lemon jam jar jet. It's proving to be fussy, not being a perfectly round shape and troublesome internal structures that I tried to scuff out.