Quotekr_ QuoteDark Alchemist Something I do find odd about the real J-Head and that is it uses Peek and peek has a Tg of 143c and I am printing at 235-250c all of the time so you would think it would get very soft. The melting point of Peek is ~343c so another 100c, roughly, before that but still I am right in the middle of Tg and Melted Peek. Anyway, the blacked PTFE tube probably happened inby Dark Alchemist - General
Quotekr_ QuoteDark Alchemist I know this as the tube in the real J-Head at 255c made the tube end black and that tube doesn't go as far in as this Chinese knockoff. It's surprising it got black. Maybe some are lower quality. Teflon's max operating temperature is 260°C according to a few datasheets and it had a memory effect at 350°C That I do not know but I do know but was simple enough to replaby Dark Alchemist - General
Quotekr_ QuoteDark Alchemist the first thing I did was unscrew the heatbreak where I found, to my surprise, a teflon tube going into the heater block. /facepalm From now on it is original for me again but the reason there is a teflon tube like that is because it is easier to manufacture AND the inner bore is so horrible that if it didn't have a teflon tube nothing would be able to get through.by Dark Alchemist - General
QuoteDragonFire Quotereifsnyderb No joke. I am the guy who created the J-Head. Sure! There are a lot of hot-end developers. Developing a hot-end, developing a hot-end that can be mass-produced, and then mass-producing the hot-end are three separate challenges. My full argument is here---> QuoteTomsand Quotereifsnyderb Keep buying the e3d knock-offs. This will drive e3d out of busineby Dark Alchemist - General
Quoteuski Here are the original drawings from E3D for the 1.75mm heatbreak. And I have attached the modified drawing showing the improperly drilled heatbreak. Still can't believe it... Copying a design should be easy enough when the drawings are publicly available... those people really don't have a clue about what they are doing.Late to the game for a response but I agree. I purchased a realby Dark Alchemist - General
QuoteElmoC At least they are admitting it is sunhokey. I'm surprised that Prusa hasn't made them stop using his name/brand on it.They are a horrible company and should be put out of business but Josef doesn't care I think from what I gathered. Call it whatever you want because he never trademarked the name. Still 3dprintersonline is a very bad company to do business with and the last time I looby Dark Alchemist - General
Quotethe_digital_dentist It's true that quality ball screws are pretty expensive when purchased new. But that's not the only way to get them. You can buy used parts or pull them out of scrapped machines as I did to get the precision ground ball screw that is in the Y axis of my printer. I paid $0 for it - just one of the many advantages to belonging to the Milwaukee Makerspace. We have almostby Dark Alchemist - Mechanics
QuoteJamesK I think CNC grade anti-backlash is usually done with ball-screws - the screw analog of a linear guide. That's a different league of thing entirely.For a company but with hobbists they are just too expensive. Off the subject but I have become a non fan of V-Rail wheels as I have some on this 3d printer I am building and there is nothing on but the X 20x40 with each side being on the sby Dark Alchemist - Mechanics
Quotethe_digital_dentist The nuts are usually brass and the screw is steel. As the nut wears, the spring keeps it pushed against the screw threads. Eventually you have to replace it, but it can probably run for quite a while before wear becomes a problem.I see anti-backlash nuts in Delrin too.by Dark Alchemist - Mechanics
Quotethe_digital_dentist On CNC mills and routers, the material you're cutting pushes back on the tool. If there were backlash it would immediately show in the part you're cutting. In 3D printing, there's no resistance to the movement of the tool other than its own inertia (and gravity in the Z axis).I can understand that but one would think the anti-backlash nuts must wear out something fierceby Dark Alchemist - Mechanics
QuotelukaCX Yes my mistake , even if you do a z-hop move you need to accelerate more that 9800mm/s ) To quote Jetguy on this matter: "Here's the problem you fail to account for when using an antibacklash leadscrew nut for an X and Y axis and further, why on a Z axis it is an added cost with no benefit. An antibacklash nut contains is a second nut that is spring loaded to ensure the inevetible lby Dark Alchemist - Mechanics
Quotethe_digital_dentist Antibacklash nuts work by keeping the nut's threads in contact with the screw's threads. In a vertical lift mechanism, assuming no binding occurs, gravity will ensure that the threads are always in contact. You should not need antibacklash nuts even if you do Z lift on retract. If you're designing this device to work on the ISS, that's another matter... "You should notby Dark Alchemist - Mechanics
QuotelukaCX Sorry for not being clear, thats what i meant ...You would only need to use an anti backlash nut if you used commands like z hop....Exactly, which I started doing as it seems to really help in the final prints for me. No idea if that will be needed with the new setup or not but for 2 or 3 dollars more I might as well go with the anti-backlash nut. Where my two acme rods will be is dby Dark Alchemist - Mechanics
Quotethe_digital_dentist I'm not a mechanical engineer, just a dentist and electrical engineer. A while back I would have said use three screws (assuming you use them properly), but these days I'd probably try two and see if the result is acceptable because it is cheaper and easier to do, and add a third screw if two doesn't work well enough. A lot will depend on the guides you use and how theyby Dark Alchemist - Mechanics
QuotelukaCX I just built a triple leadscrew core xy with 60cm Z travel. I have robotdigg mgn12 rails for the Z axis. It seems to be working fine no wobble or banding as far as i can tell. The kind of tricky bit is getting everything square and in sync.. Also buying high quality leadscrews because if they are not all machined the same that can lead to z banding...Mine will be from eBay with antiby Dark Alchemist - Mechanics
Quotethe_digital_dentist I use the Oriental Motor web site's motor sizing tools: It seems to work pretty well once you figure out what to enter into the forms.Thank you for the link. Trying to get your thoughts on the three leadscrews versus the two leadscrews is like pulling teeth, lol.by Dark Alchemist - Mechanics
Well, the main question to you was about the three leadscrew versus the two leadscrew and your thoughts on it. As far as the Tr8*8 vs the Tr8*2 quad start or single start I am sold on the single start since it shouldn't allow it to drop but what I do not know is for a bed of that size and weight what size Nema 17 would I need using either the two or three leadscrews?by Dark Alchemist - Mechanics
Quotethe_digital_dentist With 200 steps per rev motors and microstepping, almost any pitch is OK. My printer has 1/2" pitch (egads! Imerial units!) acme screws in the Z axis and I can set any desired layer thickness without any artifacts. I would try to stay with metric pitch screws. In many printer designs the X axis is lifted by two Z screws. If the screws get out of sync the X axis alignmby Dark Alchemist - Mechanics
Well, there is a really cool item I am seriously looking at and that is an aircard which is an SDcard with wifi built in. You can just leave it in the printer and save to the card over wifi then turn the machine on and there it is ready to print.by Dark Alchemist - Prusa i3 and variants
I went back to SW2014 as 2016 is better than 2015 but I didn't like it over 2014. Printing directly you must be on Windows 10? I never saw a reason to print directly because internally it is still going to STL so I just export it and print via sd card. If SW actually printed from a solid (just numbers and no conversion) I would be printing with that as STL is a horrible format in this day andby Dark Alchemist - Prusa i3 and variants
QuoteDeuxVis Sorry I haven't had a chance to work on that recently. Are you still blocked on the wiki DA ? I'll ask some other admins to put some time in here if you still cannot log in or edit wiki pages.I finally was able to log in but I had to reset my password first. I noticed Comcast has updated my ip again so it is possible I have moved to a non blocked ip but seriously with Dynamic ip sby Dark Alchemist - Administration, Announcements, Policy
QuoteVDX ... maybe your "RepRap-idea" is a different one, than Adrians He thought to give any interested in 3D-printing the chance to DIY or get a cheap kit through a sort of "viral breed" - and this is not so far from the actual situation. Even the "comercial" cheap 3D-printers are part of this "ecology" ...Nope, his idea was for the printers to be self replicating or so he said on many manyby Dark Alchemist - Administration, Announcements, Policy
QuoteVDX ... so what "OS or not OS -- this is the question ..."So what? You know I think RepRap is actually dead along with the OS movement. Just too many cheap Chinese printers out there which is far from a RepRap but I believe the whole self replication thing was just some pipe dream Bowyer thought up after hitting his pipe. RepRap is dead and no one cares as is the OS movement.by Dark Alchemist - Administration, Announcements, Policy
QuoteVDX ... many OS supporters/developers leraned the "hard way", that publishing a DIY design open is an invitation for cloners to produce low quality copies and sell them for profit ... so actually it seems, the "OS spirit" is fading away on his own Well, it is with the Chinese who do not believe in OS only stealing or w/e they wish to call it. The thing is when you get a company like MKS whoby Dark Alchemist - Administration, Announcements, Policy
I think every last one of you have lost the spirit of open source and will just do whatever in the fook. Shaking my head at the ones who would give a single damn line on the wiki to MKS as they are a shit company with a shit product and are NOT open source at all. Let them make their own wiki pages or go hang out on a wiki page that is all about closed source because this Wiki was never meant tby Dark Alchemist - Administration, Announcements, Policy
Quotemicrofortnight QuoteDust Personally I think removing it just because it doesn't comply with open source is very silly I also wouldn't remove these entries. It's a good opportunity to brand these boards as not open-source. It already saved me from buying one of those boards.That is why I said to mention it BUT label it as closed source and any information needs to be had from the seller or tby Dark Alchemist - Administration, Announcements, Policy
QuoteDust Personally I think removing it just because it doesn't comply with open source is very silly I look at it this way. Are there repraps out their with this controller? yes Does the page provide some information for them? yes I find the statement "This page is found to exist for the sole purpose of Advertising" to be a incorrect statement. So leave it marked as not open source, but leaby Dark Alchemist - Administration, Announcements, Policy
Since I can't touch it anymore would someone explain why this still exists? QuoteThis page is flagged as Advertising. This page is found to exist for the sole purpose of Advertising, This page will eventually be removed. Reason: no sources, does not comply with lowest common denominator of opensource Proposed removal date: 19/03/2015 Please use the discussion page for any questions or commentby Dark Alchemist - Administration, Announcements, Policy
QuoteDeuxVis To help me find where that blocking comes from, could you please try again and cut and paste the exact message you get ?Some reason my password does not work there so...QuoteInternal error Jump to: navigation, search Your IP address is blocked from editing, and so is not allowed to use the password recovery function to prevent abuse. Return to Main Page.by Dark Alchemist - Administration, Announcements, Policy