J-Head Mk 8 Hotend -- Small batch for sale

Hello,

A small batch of J-Head Mk 8's are up for sale at [www.hotends.com]

J-Head Mk 8's are an improvement over previous J-Head hot-ends. In addition to being the best hot-end for printing PLA, they have an axial thermistor to make installation easier, the heat is supplied by a heater cartridge, and there are two internal seals so as to make leakage practically impossible. They are available in 1.75mm only due to the available internal space.

3mm J-Heads are still available as the Mk V-BV at [www.hotends.com].

Best Regards,

Brian

Edited 2 time(s). Last edit at 02/20/2017 11:57PM by reifsnyderb.

this hotend configurable between 1.75 and 3.00 by swapping the liner, just I dont see it mentioned and its a bonus feature for us brits with 1.75 drying up

Hello,

The J-Head Mk 8 does not have the proper internal dimensions for printing 3mm. However, the J-Head Mk V-BV is capable of printing in 3mm. Both the liner and nozzle are different for 3mm and 1.75mm filaments.

Best Regards,

Brian

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this hotend configurable between 1.75 and 3.00 by swapping the liner,

I've seen this claim on a UK manufactured J-head clone I bought from ebay before ... however the melt chamber remains at 3mm dia which, I think, caused me oozing problems as I guess retraction wasn't doing much.


Cheers,
Robin.

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reifsnyderb
In addition to being the best hot-end for printing PLA,

Any proof to backup that claim? I can't say I've had any issues printing PLA with my genuine E3D V6 all metal hotend. What makes your J-Head any better for PLA?

Hello,

The J-Head Mk I through Mk III could be reconfigured by swapping the liner. The trade-off was that the melt chamber was ultra short and this resulted in higher extrusion temperatures and slower extrusion speeds. Later Mk IV J-Heads added a longer melt chamber with the trade-off being that the filament size could not be changed by swapping the liner. The end result was a much faster hot-end with a lower extrusion pressure.

Clone J-Heads don't usually follow the blueprint of the real, genuine, J-head and you could get almost anything.

Best Regards,

Brian

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Zedsquared

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this hotend configurable between 1.75 and 3.00 by swapping the liner,

I've seen this claim on a UK manufactured J-head clone I bought from ebay before ... however the melt chamber remains at 3mm dia which, I think, caused me oozing problems as I guess retraction wasn't doing much.


Cheers,
Robin.

Hello,

For starters, a real J-Head doesn't require a cooling fan on the hot-end. (It is recommended for PLA; but, not required.) The use of the PTFE liner up to the melt zone results in lower extrusion pressure. J-Heads also will print PLA at slightly lower temperatures than e3d's.

Here is a web page from a highly experienced 3d printer owner that compared e3d to J-Heads. The J-Head prints are on the right. [www.flickr.com]

Real J-Head hot-ends are also very light-weight and have printed for years, under heavy use, without problems. Please do not compare real J-Head hot-ends to cheap clones that just use the name.

Best Regards,

Brian

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PDBeal

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reifsnyderb
In addition to being the best hot-end for printing PLA,

Any proof to backup that claim? I can't say I've had any issues printing PLA with my genuine E3D V6 all metal hotend. What makes your J-Head any better for PLA?

NO ONE should confuse/compare a clone with the genuine article , "I have two mkV and they are worlds apart from there grubby clone counterpart ". if you gonna just use PLA the J head a good choice no need for extra wiring of a fan, smaller than a V6 you can print as low 178C.
a jinxy fact: the Jhead has to be one of the smallest hotends on the market think the Deltaprintr Mini Hotend the only comparable HE in term of size but thats a different ball game. so if Z height an issue "or lack off" the jhead gets the thumbs up!.

reifsnyderb:
I like to see the V8 with a bowden adaptor straight into the peek would that be possible?. I've added so much weight to my X axis going back to a direct drive, causing hot sweats thinking about it!!

PS shave of 1.5 mm of the top of the grove and It be able to mate with a titan " hell of a love child that be

Edited 1 time(s). Last edit at 02/21/2017 02:01AM by jinx.

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reifsnyderb


Here is a web page from a highly experienced 3d printer owner that compared e3d to J-Heads. The J-Head prints are on the right. [www.flickr.com]

Im sorry to say but your highly experienced 3d printer owner look like he cant figure how to set a e3d or a simply bias to your J-head and he make sure the setting was off on the e3d to give that kind of result, Im not saying your J-head are not good but those are one of the worst e3d print I saw in a while.

Edited 1 time(s). Last edit at 02/21/2017 05:25PM by GroupB.

It looks interesting, especially the smaller form factor compared to an E3D and the internal seals. Have you used nGen in it? This stuff really turns to liquid and leaks out of any gap. It's possible to stop this on an e3d but its quite a pain. Although nGen might be towards the limit of what you can print on a J-head....

Also, I'd probably not use that source to promote the J-head. I've got hundreds of prints of varying complexities printed by an E3D that prove it's wrong, as do a lot of others.

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reifsnyderb
Here is a web page from a highly experienced 3d printer owner that compared e3d to J-Heads. The J-Head prints are on the right. [www.flickr.com]

Worth noting that comparison is against an E3Dv5, not an E3Dv6.

I didn't understand what you are saying

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Maria
I didn't understand what you are saying

use google translate!!! fun aside... I think you need to be a little more specific who you replying too. they are discussing these > images which I cant relate too, I had better results from both those hotend with PLA.

Edited 1 time(s). Last edit at 02/22/2017 02:37AM by jinx.

Can you tell me how much the MK8 weighs and what is total length? Also will the top of the MK8 support a screw in PTFE bowden adapter?
Thanks

Hello,

The J-Head Mk 8 weighs 18 grams and is 50mm long. 40mm projects below the mounting groove. The Mk 8 does not have a built-in PTC connector.

Best Regards,

Brian

I just wanted to say that I totally agree the J-head MK V-BV is better than the E3D v6 when printing PLA in regard to print quality, at least in my case it was. Now the E3D Lite6 is a step forward IMO and both have qualities the other does not. Looking at the two you would automatically assume the E3D is far superior and I believe for this reason and the fact that it can safely print over 240-250C it became more popular and pretty much the industry standard.

My first build (Mini Kossel) featured a J-head and for the longest time I couldn't figure out why so many people encountered clogs until I actually tried a E3D V6 with fan at 100% always of course. The J-head never did clog and this was with no fan running in a fairly warm room.

Some of my prints from around two years ago: [tinypic.com]

Still some left...