Started on a hotend that can go over 300 c, I have got a Smoothieboard, and in process of setting up a head assembly to see
what this will take. I have a 40mm fan, and have built in louvers to help to direct the cooling of ceramic, and aluminum holder,
(upper hotend piece), and a deflector to decrease amount of heat being blown back to the hotend tip.
The overall height will increase by about 5/8". I will post as I build it.
I do hope that such a hotend can become a reality.
The problems that I can think of is if the PTFE tube can work in such temperatures.
Best of luck in building this!!
The PTFE tube is only good to about 250C and even at that PTFE will deform, it also puts out very dangerous fumes if it gets too hot.
Using something to structurally support a central PTFE column is something that has been used many times in designs, but I think you'll find you won't get away with just a 4mm tube in there because of the deformation. Many of the early hotend designed tried to use Teflon structurally and they all failed, later they used other materials to support it which is why until the all metal hotends appeared most used a teflon tube inside a PEEK structural element.
The Ceramic hotend thing has been tried, the Chess Hotend springs to mind the original idea there was that the ceramic would be smooth enough to not require the PTFE, that turned out not to be the case at least for their initial batches, so they are sold with a PTFE tube in them.
One concern I would have is the length of the transition zone, and what happens as the ceramic starts to soak heat in from the heater below it, I suspect it would take a long time to stabilize, and it's properties will be changing until it does.
A longish transition zone isn't necessarily bad on it's own, but it can lead to problems with retractions and dribbling, but the JHead which I and a lot of people still consider the best hotend for PLA doesn;t have a particularly short one.
Now having said all of that the only showstopper I see is the PTFE, let us know how it goes.
Thanks Guys
Had a bad feeling about Teflon due to the toxic fumes on over temperature, Has anybody tried high temp graphite, it will take temps to 426 C, I don't
know if it will rub away from the filament. People I guess need this temp for the new flex material.
High Temperature Conductive Graphite maybe 1/4" Diameter or better. I want to print poly carbonate.
What do you think?
Jack
draw-tech
1/2" diameter x 6" long about $15
Color: Opaque black
Maximum Temperature: 800° F
Tensile Strength: Good
Impact Strength: Not rated
Electrical Insulator: Not rated Machine: Use carbide tooling
Hardness: Not rated
The very fine grain of this graphite adds strength and density to this conductive, heat-resistant material. It is often used in applications that require resistance to high temperatures, such as fabricating furnace parts, and to manufacture crucibles or ingot molds because it does not adhere to metal. When oxygen is not present, the maximum temperature of this material is 5000° F.
I use graphite carbon journal bearings in high load applications. They are always lubricated, but we do perform accelerated wear testing in a dry state and the failure point is normally a hard chrome shaft rather than the bearing itself.
I would expect very good life used as a sleeve. It will rub off a minor amount at first, but should settle down. I don't think a little bit of carbon will hurt the filament much other than possible discoloration.
draw-tech wrote:Thanks Guys
Had a bad feeling about Teflon due to the toxic fumes on over temperature, Has anybody tried high temp graphite, it will take temps to 426 C, I don't
know if it will rub away from the filament. People I guess need this temp for the new flex material.
High Temperature Conductive Graphite maybe 1/4" Diameter or better. I want to print poly carbonate.
What do you think?
Jack
draw-tech
1/2" diameter x 6" long about $15
Color: Opaque black
Maximum Temperature: 800° F
Tensile Strength: Good
Impact Strength: Not rated
Electrical Insulator: Not rated Machine: Use carbide tooling
Hardness: Not rated
The very fine grain of this graphite adds strength and density to this conductive, heat-resistant material. It is often used in applications that require resistance to high temperatures, such as fabricating furnace parts, and to manufacture crucibles or ingot molds because it does not adhere to metal. When oxygen is not present, the maximum temperature of this material is 5000° F.
Great potential. I like the way this group thinks.
One thing to keep in mind most thermistors go up to 300°C. Beyond that you'll be switching to a thermocouple. I not sure what other changes that would entail but I'm sure someone on here is better versed in this area.
Last edited by drwho on Mon Oct 19, 2015 2:12 pm, edited 1 time in total.
Maybe if you change the nozzle type to a Prometheus style, you can extend the nozzle high enough into the heat-sink. Maybe then the PTFE bowden style tube could work?
drwho wrote:Great potential. I like the way this group thinks.
One thing to keep in mind most thermistors go up to 300°C. Beyond that you'll be switching to a thermocouple. I not sure what other changes that would entail but I'm sure someone on here is better versed in this area.
Hi dryho
Did some research on thermistors, you need to check out this place in Cal. http://adsem.com/gpage1.html" onclick="window.open(this.href);return false;
Says will do 500 C+
If you're already looking at special thermistors, why not consider something like the PT100? even higher potential temperatures, plus a more solid physical package, and wide-spread compatibility. I understand that the latest version of repetier supports them out of the box, E3D offers a reasonably priced adapter board (plus you could make your own if you don't care to go with E3Ds). They are larger though (1/8 inches appears to be the perfect size of hole for them to slot into), and do require you to wire the amp to different pins from the thermocouple jacks. Although I figure a novel thermistor like that would have some teething troubles to match the hassle of a PT100.
Machines:
Rostock Max V2, Duet .8.5, PT100 enabled E3D V6 and volcano, Raymond style enclosure
Automation Technology 60W laser cutter/engraver
1m X-carve router
"Need more specialized 3D printers than a kit level"
Are you kidding me?
I think the only way you could top that statement would be to crash a My Little Pony convention and scream, "BRONIES ARE A BUNCH OF PUSSIES!" at the top of your lungs. The results will be....familiar.
Heh. Keokolo, I will point out that E3D and matterhackers both provide PEEK filament, that E3D rates it's hotends to 400C+, and similar. The Rostock Max is also an extremely capable and adaptable machine. I doubt that Airwolf's machines can beat a well-tuned, well modded Max like Mike's. For that matter, I have a printer that can match if not beat every spec on their AW3D printer, for half the cost. A kit machine, like a home-brewed computer, is a variable beast. The good ones are better than anything you can buy, and the bad ones just don't work.
However, I will admit that we cheat compared to the people designing machines for sale. Development is massively parallel, and time isn't charged for. We can also roll-out changes and updates very rapidly. Operators are also expected to know what they are doing, and how the machine works. That sort of luxury is rare with industrial systems.
Don't dis kit machines, and especially open source kit machines. The bazaar method of development works, and does so extremely efficiently. There's a reason Linux has taken over such a huge percentage of supercomputers and servers. When you need the very best you can get, you go for what you can tweak and refine. Same thing with printers.
Machines:
Rostock Max V2, Duet .8.5, PT100 enabled E3D V6 and volcano, Raymond style enclosure
Automation Technology 60W laser cutter/engraver
1m X-carve router
Kit level printers are fine if built for the purpose. I have made polycarbonate prints with my Mendel through an E3D v6. I'm running it a little cooler than you list there, so I haven't even had to go to a thermocouple yet. Even the RepRapPro quick set hot end should be capable at this point.
IMBoring25 wrote:Kit level printers are fine if built for the purpose. I have made polycarbonate prints with my Mendel through an E3D v6. I'm running it a little cooler than you list there, so I haven't even had to go to a thermocouple yet. Even the RepRapPro quick set hot end should be capable at this point.
Hi imboring25
Who's material are you using, what temp., and is it transparent???????
I've done some more work on the HI temp head. Going to try a homemade cartridge heater. and the new design. I have isolated
the top and bottom aluminum parts by ceramic, Graphite, and PTFE at very top. Will be cooled by a 40mm fan, in oversize housing
It's GizmoDorks transparent polycarbonate. I've been using 285 to give a little margin against burning up the thermistor. I haven't tried printing fast with it. That's probably where a higher temperature would come in.
That is a good point. Going hotter would probably add to the transparency as well. It's by far the clearest material I've used, but maintaining as much optical clarity as you can will make keeping moisture out of the filament critical and depend on thickness and style and percentage of infill.
Not dissing kit machines, just saying, look at the power supply. Surplus PC power supply might have a tough time with the increased current for polycarbonate and PEEK. The stock arms are slightly wobbly and this makes stringiness hard to control. And yeah, you have to get a new hot end first, at the very least. The advantage of a kit machine is finding out all the parts that need upgrade and replacement. The cost of doing this goes up against the coming next generation. For me, don't really have a need for polycarbonate or PEEK right now, there is still a lot of value in PLA, ABS and PLA composites. The new PLA and PET composites can be very hard or very flexible, low moisture absorption, no warping, getting close to injection molded plastic strength with ABS melt temps.
IMBoring25 wrote:That is a good point. Going hotter would probably add to the transparency as well. It's by far the clearest material I've used, but maintaining as much optical clarity as you can will make keeping moisture out of the filament critical and depend on thickness and style and percentage of infill.
The reason I need transparent, I am printing my entire model Harley Knucklehead, and i want to be able to see inside, for moving parts. There are around 283 pieces. Keokolo, Figured I might need a more powerful supply, got it covered 800 W, There is a small section of peek, cooled with 40mm fan. I hope that it will work on the flex material also. I have made the cartridge heaters, and most of the head, will be setting on a test stand to see what craps out. Here is a pic of Octave's transparent, and I print solid in most cases.
If maximum transparency is your only concern for this application, I'd look into PETG rather than polycarbonate. In addition to needing a hot end that can approach 300C, PC is likely to take something close to 130-140C on the bed to get it to stick at all, and I've still only gotten it to stick long enough for small parts.
You can definitely do better than "transparent" ABS, but if you're looking for something that approaches the almost-jeweled character of your typical transparent desktop model, I don't think you'll get all that close from FDM technology. A resin-based printer will come much closer.
I'm also puzzled by nitpicking the cost of how much has to be changed when a commercial machine capable of using the same materials would be multiple tens of thousands of dollars.
And heck, even the hotend of a makerbot replicator costs more than this would, even with the economies of scale makerbutt has, and can't do the temps this calls for. Admittedly, I went for an E3D hotend to get high temperatures, rather than making my own, because I liked what I saw, and didn't figure I knew enough yet. But projects like this are how state of the art advances. You do your thing, Draw-tech, and maybe your hotend will be the best thing since sliced bread. Don't let anyone get you down by saying kit builds or homebrew's aren't as good. Everything started somewhere. Makerbot used to be a tiny company making printers that were equally small, and look where they are now (OK, look at them before the stratsys buyout). Rep-rap machines used to be slow, expensive, and in-efficient, as well as limited in their designs, but now there's a whole ecosystem of them, with the rep-rap machines being quite excellent, although I still prefer my Rostock.
That German PEEK printer? Can probably be beat by someone with an E3D hotend and PT100s. For a fraction of the cost.
Makerbot machines? Don't make me laugh. Pretty much any rostock that can display something on the LCD would be preferable.
Stratasys printers, the big industrial ones? We have one on the campus. Makerbot beats them, and with a smaller form-factor, better interface. Rostocks look like a six figure printer in comparison. They don't have a heated bed at all, and have cartridges with expiration dates.
Then you have travesties like the Cobblebot, or the Buccaneer. Plain and simple, pre-built printers without the adaptability seem to be failures.
To be a hobbyist or a kit builder is to be on the forefront of the technology at this point. No big industrial printers are delta's yet. Few can do triple or quad extrusion. Few have the nice enough interface you get from the rambo, much less the excellent interfaces of the Replicape with a Magna screen, or a Panelduo. And none of them are so cheap, so capable, and so adaptable. Very few of them even look as good as the Rostock. Don't worry about what happens. You can't do a worse job than the professionals.
Machines:
Rostock Max V2, Duet .8.5, PT100 enabled E3D V6 and volcano, Raymond style enclosure
Automation Technology 60W laser cutter/engraver
1m X-carve router
Xenocrates wrote:And heck, even the hotend of a makerbot replicator costs more than this would, even with the economies of scale makerbutt has, and can't do the temps this calls for. Admittedly, I went for an E3D hotend to get high temperatures, rather than making my own, because I liked what I saw, and didn't figure I knew enough yet. But projects like this are how state of the art advances. You do your thing, Draw-tech, and maybe your hotend will be the best thing since sliced bread. Don't let anyone get you down by saying kit builds or homebrew's aren't as good. Everything started somewhere. Makerbot used to be a tiny company making printers that were equally small, and look where they are now (OK, look at them before the stratsys buyout). Rep-rap machines used to be slow, expensive, and in-efficient, as well as limited in their designs, but now there's a whole ecosystem of them, with the rep-rap machines being quite excellent, although I still prefer my Rostock.
That German PEEK printer? Can probably be beat by someone with an E3D hotend and PT100s. For a fraction of the cost.
Makerbot machines? Don't make me laugh. Pretty much any rostock that can display something on the LCD would be preferable.
Stratasys printers, the big industrial ones? We have one on the campus. Makerbot beats them, and with a smaller form-factor, better interface. Rostocks look like a six figure printer in comparison. They don't have a heated bed at all, and have cartridges with expiration dates.
Then you have travesties like the Cobblebot, or the Buccaneer. Plain and simple, pre-built printers without the adaptability seem to be failures.
To be a hobbyist or a kit builder is to be on the forefront of the technology at this point. No big industrial printers are delta's yet. Few can do triple or quad extrusion. Few have the nice enough interface you get from the rambo, much less the excellent interfaces of the Replicape with a Magna screen, or a Panelduo. And none of them are so cheap, so capable, and so adaptable. Very few of them even look as good as the Rostock. Don't worry about what happens. You can't do a worse job than the professionals.
Thanks all for the lift
Don't worry about quitting, I'm not afraid of burning something up, to prove my point. as for the power supply thing I just want an external power supply so large is to cover other projects I have in the pot. I love this max, I'm convinced that for the money you won't find better. The changes that I make are no different than a car nut, were just souping it up to meet our needs. Here is what I have made so far, waiting on the graphite, and the PTFE to come in. Doing the milling tomorrow.
Assembled
FYI the ceramic is a tig Torch Shield from a welders supply, for about $1.50
The Extruder
