Lets talk hot ends...

for my delta i went with a budaschnozzle v2.0 from makergeeks.com

im currently working on building a prusa i3 steel and realized i dont like how the j-head hot ends i have fit in the extruder carriage. I believe the bore isnt deep enough and causes the hot end to wobble. so i thought why not go to the same budaschnozzle like i used on the delta.

my question is has anyone used the chinese knockoff's listed on Ebay or am I better off biting the bullet and buying another from Makergeeks? the concerning part for me is they say it shouldnt be used over 247deg. C..

Thoughts?

See my topic called "prints always fail at he same point"

yea i learned my lesson with the knock off v6 hot ends. i have 2 of them and havent even made a single good print with them at all. thats why i went to the budaschnozzle... but the design is a bit different so wasnt sure if it would have the same issues. obviously thats one of my fears.


did you ever get a DVM on the heater cartridge and see if that was the issue?

I have a couple of 3mm stub mount thermistors I am going to try.

What is it about the knock-offs that are not made properly?

the ones i have seem to be a heat soak issue more then anything. even with having a 30mm fan on it and wraping the heated block with insulation i still seem to get issues with the nozzle clogging

The 247 degree limit is imposed by the PEEK material that is used as heat break. It will get soft at lower temps than that and under higher pressures (faster prints) will get the heater block pushed out. I got a cheap jhead and ran it up to 230 degrees with no problems (the PLA wades extruder didn't fare so well though).

I now use the all metal E3D V6 (not sure if it's the original or chinese made) with thermo couple. I bought from reprapworld.com. I really like them, with a 0.4 nozzle it rarely cloggs up (1 in 100 prints maybe better, depending if I use ABS and leave it heated without extruding too long).
With the 0.35 it was much worse though, not sure why 0.05mm makes such a difference. I also have a 0.6mm nozzle which is also very good, it allows fast print speeds due to higher layers and wider extruded filament.

The heat break design works pretty well, with a fan even at very low speeds (near silent running fan) cools the heat break well. At full speed my hot end had trouble to maintain 280 degrees for nylon. I redid the PID auto tune and now prints very well at 280 degrees.
The modular design is great to easily maintain the hot end. heat breaks, cooler fins, heater blocks etc can be bought separately.

I own two e3D v6, the second one will be the second extruder I plan on building into the Prusa i3. I need to redesign the mount on the x carriage first. I want to use a single fan cooling both heat breaks as the fan has plenty of cooling capacity and I want the most compact design to maximize build space. The farther the nozzles are apart the smaller the build space.

Hello,

I am the inventor of the J-Head hot-end.

Makergeeks does not sell properly made J-Head hot-ends. In fact, most "J-Head" hot-ends are just chinese knock-offs. A proper J-Head has 5 rows of vents instead of 4. Proper J-Heads are built as per the specifications on [reprap.org].

PEEK works great up to 248 degrees. However, due to thermistor tolerances, 240 degrees is recommended.

New J-Head designs will not be released as I refuse to china's R&D dept.

Best Regards,

Brian

One option to deal with this, if you come up with good improvements again, is to go the patenting route. In the US, you could start by having a Design patent application drafted and filed for you by a patent agent for around $800, and then if you want, you could have a Utility patent application drafted and filed for about $4000. Then you can have much more control over who does what with your designs.

Quote
RRuser
One option to deal with this, if you come up with good improvements again, is to go the patenting route. In the US, you could start by having a Design patent application drafted and filed for you by a patent agent for around $800, and then if you want, you could have a Utility patent application drafted and filed for about $4000. Then you can have much more control over who does what with your designs.

Sure,
you only need xxx.000.000$ and a bunch of lawyers to defend your patent.

Been there, and thankfully didn´t do it
-Olaf

Well, if you have a decent issue patent (and sometimes just a decent pending application) with nice claims, then there are IP firms which will handle it on a percentage basis, or, you can license it to a larger company who can do the legal work for you. Costs no money.

the bigger issue with patents is it doesnt matter if you patent it 6 ways to sunday...the chinese mfg's will copy them anyway because they know the expense it takes to fight something like that internationally.

my post was not a stab at the design. everyone is guilty of looking for a more cost effective way to procure components.

my post was mainly directed at the budaschnozzle style hot ends not the standard J-head style. If I still had my lathe i wouldnt be posting at all and would just make my own parts. but unfortunately i dont...