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28Oct/10Off Hotend v3.0

This is a really big announcement.:-) The new hot-end has been born, and rocks!

For those who have missed, there were some previous prototypes, namely v1.0 and v2.0, and also v2.1, v2.2, v2.3, v2.4 and v2.5 what I have not published, and also many more trial, just I didnt brother to versioning them.

So what was wrong with the previous prototypes?

Well, it worked great for 2-2.5 hours, but after the filament melted upward in the hot-end that the extruder could not push the plastic anymore. So I sit back to the drawing board, and I redesigned it.
The new prototype works so great, that it melts about 10mm of the filament in total.
Here is a comparison photo for the non-believers;-)

This is a real problem on many extruders, hot-ends. I had many problems before with my Rapman machine.

Mounting on different machines
That was the main reason, that I designed this hot-end as a drop-in replacement for Rapman machines:

Still some spacer disks required to make the hot-end longer, as it is too compact for the Rapman machine. I think fewer spacer disks are enough, just didnt have shorter bolts at home.

Mendels (standard and Prusajr variation)
And also basically this mounting is the only one, which have adapted to Mendel, and also Prusajr Mendel variation has mountings by default for this hot-end.

Im also working with Kliment for adapting the mountings for Makerbot machines. (Kliment: your parts are already lasercutted!;-)

Heater block

I reduced the nozzle mass so great, that it requires less then 2 minutes to heat up this nozzle on a standard Rapman machine! (usual warmup time is about 5 minutes, but I need to verify it with a stopwatch. I will update the article with proof-videos)
Here is a picture:

Please note, this heater block was handmade from a previous prototype, the mass produced hot-end will have a much more beautiful one, like this:

(the picture is taken from the upcoming assembly manual article)

Nozzle orifice

The current prototype has a 0.35mm orifice:

But I also have manufactured two 0.5mm ones.

Wire relief

The wire relief was improved further since the previous prototypes (section 6. in that article). Picture:

It protects more the thermistor, and also it prevents further against unscrewing.
(The hot-end is manufactured in a way that it prevents unscrewing by default, but some more (unneeded) security is always welcomed;-)

Heatsink (cold part)

I added more heatsink to further improve cooling of the filament. Maybe it is not necessary, as the filament does not melt upwards, but I like overengineering this part of the hot-end:

Also I additionally put a heat insulator at the bottom. The holding spacers act in this design as a heatsink, while in the previous design they were the major source of trouble because of conducting too much heat upwards. (And its the weakest point in the Rapman stock hot-end design).


I was able to print parts, what I was unable to print with Rapman before (with 0.5mm orifice):

That part is 200mm long.

Im printing with this hot-end since this sunday, and there were no problem with it. Starting the extruder at the other day (so there are som filament already in the extruder) cause no problem at all.

I need to finetune skeinforge for 0.35mm orifice, and also in general, because my parts looks ugly, but it is not because of the hot-end! It prints really great:

Final image

I have three prototypes now. Two additional were manufactured:

These two have 0.5mm orifice, and also much nicer heater block. The final version will contain some more little touches here and there.

Introductionary video

I compiled a short introductionary video: hot-end v3.0 from on Vimeo.

(sorry for my crappy accent)

I want this hot-end, how can I order it?

The best is droping an email to order (at] with your address. Shipping is possible worldwide, payment via paypal. If you have any question just ask in that mail.

I will also put hot-ends on ebay too, for those who want to licit against each other.

For preorders the price will be ??EUR with ?EUR shipping, I will ship them next friday (nov. 5), if nothing bad happens. For ebayers, it will be more expensive I believe.

So anybody ordering the hot-end (by email) until next friday can have this price.

I do believe this is an exceptional deal for this great hot-end. Also remember further nozzle can be ordered in the future if you dont like the current one (different orifice, different inner structure, etc).

Im really proud of this hot-end, I think I incorporated all of the plastic knowledge into this (at least my knowledge;-).

Shipping to different countries

If you can pay via paypal or wire transfer, I can ship it to you:)

The ?EUR shipping price is valid worldwide. No matter where you live in Europe, or the US or even Australia.
It is an introductionary price, so be wise, and order it now!;-)


Well I need to write an assembly manual for it. (I already took 110 pictures of each step yesterday during assembly).

And also publish design files on thingiverse, and fill the wiki.

Other announcements

I have started a wiki page, about all stuff what Im selling at
I will keep that page up to date. So if you want more info before buying anything, you can look up there.

Im working on a webshop software, but currently ordering is possible via email, or bidding on ebay. (seller is "")

I hope you enjoyed the ride, and you like the resulted hot-end!

Update: I erased the introductionary price to not confuse people.

Comments (6) Trackbacks (2)
  1. Looks good. Are you going to publish drawings?

    Is it in optical illusion or does the nozzle have a concave tip?

  2. What’s that black greasy stuff on top of the heater? some kind of glue?
    Do you plan to include even smaller nozzles? like 0.3mm or even 0.25mm?

  3. nophead: I will slowly publish more documentation. (sorry Im only a human beeing)

    This whole extruder will be licensed cc by-nc-sa. Im also open to relicense it after half year, if the reprap developers want other license.

    It can happen that the nozzle has a concave tip although its not on purpose. The “central drill” (dunno what is the proper english term) on the lathe may “pushed out” the aluminium.
    I also bought 0.5, 0.8, 1.0 mm central drill bits for the lathe (it is also called marker drill still im unsure what is the english term).

    The black greasy stuff is burned black ABS.
    Yepp, I have already bought 0.2mm drill bit(still not arrived).
    Everyone who buys now, can later upgrade to other nozzle.
    I plan to sell other nozzle size for 10EUR/piece.
    As of now only 0.5 and 0.35mm orifice is possible.

    Also those tiny size are real challenge to manufacture on a lathe. So it depends on the lathe too, what size we can manufacture. The smallest drill bit, what I can buy is 0.06mm.

    Best regards,

  4. Yes Lazlo I agree with you about only being a human being. How is the cc by-nc-sa working out? I am interested in some level of publishing and marketing that does not involve so may hoops but gets a level of property right protection keeping those that merely want to catalog everyone’s work.

  5. Can I ask a stupid question?

    I have been unable to find an e-mail address on your blog or wiki, so which address do you want to be contacted on if I would like to purchase your hot end?

    Maybe you could get back to me on my e-mail, it should be attached to this comment?

    Thank you.

  6. I want one too.
    Reprap(at )