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Best hot end

Posted by fredted1234 
Best hot end
June 17, 2012 01:58PM
I'm am looking at buying a hot end now and am not sure if this one is off good quality, I have a gregs hinged extruded and ramps electronics. I do like a bargain but don't mind paying extra to ensure the printer will perform to the best level it can.
This is a hot end I was looking at, does anyone have any experience with it? Or know anything about it?

[www.ebay.ie]

Thanks
Reply Quote Report
Re: Best hot end
June 17, 2012 01:59PM
You don't have any link to the hotend.
Re: Best hot end
June 17, 2012 01:59PM
Sorry here's the link

[www.ebay.ie]
Re: Best hot end
June 17, 2012 02:48PM
J-Heads have a good reputation. Personally I'm very happy with my arcol v3, and have used it for 6-7 months without major issues. (I haven't tried v4 though).

I'd advice against buying random unknown, untested home made hot ends from ebay, but maybe that's just me.


--
-Nudel
Blog with RepRap Comic
Re: Best hot end
June 17, 2012 04:30PM
I have been getting great results with the MakerGear hot end. They answer emails promptly and will help with any problems.

http://www.makergear.com/products/operators-pack
Re: Best hot end
June 17, 2012 05:07PM
Makergear, Arcol, Hotends.com, Lulzbot all have very good reputations in the IRC


repraplogphase.blogspot.com
Re: Best hot end
June 22, 2012 04:05AM
I just want to bring this up again, that hot end on ebay looks very decent, see his description. I have checked his 132 positve ratings and everyone seems very happy with it, surely someone here has tried it? maybe at the least one of you more experienced folk could take a look and give your opinion. Seems more than just some homemade crap to me.
Re: Best hot end
June 22, 2012 05:30AM
The fact that this hotend mechanically supporting parts are made of PTFE doesn't help trust on its reliability.
As PTFE slowly creeps and deform when heated, all hotends who ever relied on it to attach itself are doomed to early failure.

Would the lower PTFE part be made of PEEK instead, it might be worth a test then.


Edit : here's the hotend design :



Edited 1 time(s). Last edit at 06/22/2012 05:34AM by DeuxVis.

Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.

Re: Best hot end
June 22, 2012 05:43AM
Thanks, that makes sense. Does anyone have any suggestions for the most affordable hot end that produces good, consistent resolution? Even if it is DIY...
Re: Best hot end
June 22, 2012 05:55AM
Buy a cheap mendelparts V5 clone from reprapworld, add some nuts above the peek support block so it can't move up when hiting the bed and deform the ptfe thermal barrier, and you should have a simple working solution.


Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.
Re: Best hot end
June 22, 2012 08:03AM
I've found that the LulzBot Budaschnozzle 1.1 is really good. It is quite pricey ($95) though, but I have only ever had one problem with it and that is my fault. I also have experience with J-Heads, and have had a lot of problems with them. The Budaschnozzle makes for some nice quality prints.

Here is a link if your interested:
[www.lulzbot.com]

Edited 1 time(s). Last edit at 06/22/2012 08:04AM by Acarius10.
Re: Best hot end
June 23, 2012 04:44AM
I have to disagree with Deux. The Wildseyed hot end uses only a PTFE rod for mechanical support, and it works fine.

There have been some designs that failed, and those were all threading the hot end into the PTFE. The PTFE would expand, and the hot end would fall out.

The design shown in the above clearly follows the same approach in threading the PTFE into the hot end, insuring that the expansion provides extra gripping. I don't see a problem with it
Re: Best hot end
June 23, 2012 12:02PM
I have never understood how the Wildseyed hot end works. I made something very similar, PTFE that screwed into a brass nozzle and it failed during the first layer. PTFE has not strength at ABS extrusion temperatures and simply elongates.


[www.hydraraptor.blogspot.com]
Re: Best hot end
June 23, 2012 05:14PM
The hot end of the extruder is critical. I feel the hot end used by Makerbot is simple and reliable. Its a nozzle, thermal core which connects the nozzle to the steel down tube and a PTFE liner. I'm using this design and rigidly connecting that lower end to a steel plate without using those outer connecting screws that pull the lower end up towards the extruder.

Most are still using those outter support rods that have many issues. Like the one pictured here you draw the hot end up and think its tight. The you put over 220deg on the hot zone only to find that the PTFE support starts to deflect under the heat and tension of the support rods. Eventually the lower end becomes unstable and starts bending. So you tighten the support rods and it happens again.

Support rods connected to anything other then steel will deflect and fail. Same with PTFE components that are part of the support of the lower end. I just think that the best route is to no use support rods of any type and simply secure a steel down tube to the underside of the extruder.
Re: Best hot end
June 24, 2012 06:23AM
jcabrer Wrote:
-------------------------------------------------------
> I have to disagree with Deux. The Wildseyed hot
> end uses only a PTFE rod for mechanical support,
> and it works fine.
>
> There have been some designs that failed, and
> those were all threading the hot end into the
> PTFE. The PTFE would expand, and the hot end
> would fall out.
>
> The design shown in the above clearly follows the
> same approach in threading the PTFE into the hot
> end, insuring that the expansion provides extra
> gripping. I don't see a problem with it

Rather than the way the metal barrel is screwed into or around the ptfe, what bothers me here is the fact the rods that maintain the hotend are attached to a ptfe plate - I can't see what would avoid the fast deformation of that plate.

Can't tell for the Wildseyed simple hotend as I never tried, but it seems to be a different design, only transmitting forces through the length of the thick ptfe cylinder, and so maybe it can last longer indeed - as long you do not crash the head in the bed ?


Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.
Re: Best hot end
June 24, 2012 01:16PM
I'm very new to this whole Reprap business, so only have personal experience of the bits I have made/used. I wanted to make as much of my Prusa myself as I could, as for me the build and associated design decisions (even when based on near-zero knowledge...) is at least as important as having a working machine. I bought a kit of printed parts from eMakershop and than had a hunt around for a hotend design to go with it. I chose the "Adrian" design, as it seemed to be straightforward to make and had a few sensible design features. Although my version does have a few differences, I have to say that it seems to work fine. Main difference from the published design is that I skipped the threaded PTFE bit. There are a couple of adequate clamp bolts holding it all together so why bother with fiddly threading, especially with PTFE? The heater block is screwed on to the nozzle, and I used a PEEK clamp bar as I found someone selling short lengths on eBay at a reasonable price. I also found that I didn't have any threaded rod or bolts long enough for the clamps so I used a couple of lengths of hex brass tapped at each end; one end acts as a nut to hold the extruder to the X-carriage and the other end takes the bolts through the PEEK. There is a bit of clearance on the length to make sure that the clamp bar pulls up tight and holds the whole thing together. I worried about not finding a round wirewound resistor and ended up with a rectangular one but I just milled a slot in the heater block and stuck it in with a bit of fire cement. All-in-all, I am surprised just how tolerant the hotend design seems to be, but maybe I either struck lucky or I just don't know any different! Next one will be slightly different, but mainly because there is too little nozzle projection from the heated block which ends up too close to the object being printed.

I can't imagine putting more than 20% of the cost of the printer components into the hotend alone, but I am lucky enough to have the machining facilities to do the simple turning and milling needed. And it was no more than a couple of evenings' work, not much more than cutting and neatly facing and chamfering the ends of all the frame rods.

There has been a lot of talk here about which commercial hotend is best, but not much about why (apart from not relying on threaded PTFE....). So just what are the key design features? No-one seems to have mentioned nozzle external profile, heater block clearance, or things like that. What are the critical points about a design that really matter, and which are relatively unimportant?
Re: Best hot end
June 25, 2012 04:28AM
DeuxVis Wrote:
-------------------------------------------------------
> Buy a cheap mendelparts V5 clone from reprapworld,
> add some nuts above the peek support block so it
> can't move up when hiting the bed and deform the
> ptfe thermal barrier, and you should have a simple
> working solution.


Isn't the v5 way outdated now? I want bang for buck not necessarily the cheapest solution, I will be ordering other stuff from reprapworld though so it makes sense to get the v5, I'm just worried about print quality.
Re: Best hot end
June 25, 2012 11:45PM
RegionX Wrote:
-------------------------------------------------------
> Does anyone have any
> suggestions for the most affordable hot end that
> produces good, consistent resolution? Even if it
> is DIY...

And then later :

> Isn't the v5 way outdated now? I want bang for
> buck not necessarily the cheapest solution, I will
> be ordering other stuff from reprapworld though so
> it makes sense to get the v5, I'm just worried
> about print quality.



Well I've been using a V5 (from mendelparts) for half a year on my Huxley, was producing nice parts once I managed to properly calibrate the extruder. See this yoda for instance : [forums.reprap.org]

It's starting to fail now, leaking between the pfte and barrel, but that probably because I didn't secure the hotend properly (attaching even partially the ptfe to the x carriage is a bad idea, all the efforts should go through the rods which secure the peek block).


Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.
Re: Best hot end
June 26, 2012 04:00AM
That is a good print but from what you say I think maybe it is worth the extra money. Just getting raped by shipping and exchange rate.....
Re: Best hot end
June 28, 2012 04:16AM
[www.ebay.com]

This one is 58$ including shipping and avoiding exchange if you're in the USA, another design but looks fine too.

This is from forum user snoopy (his thread here)


Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.
Re: Best hot end
July 02, 2012 01:51AM
I'm about to change my mind about recommending you that V5 - I just realised it's so very easy to break the ptfe threaded part if you don't pay attention to every detail...


Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.
Re: Best hot end
July 02, 2012 08:37AM
Going with J-headthumbs up
Re: Best hot end
November 11, 2012 04:00AM
Hi,

I got one of these a couple of weeks back as the design looked ok at first glance, but I wouldn't recommend getting one. The PTFE insulator does deform very quickly as the "labyrinth sealing" basically passes the heat right up to the top of the threaded part of the PTFE insulator. Where it threads in to the "labyrinth sealing" it is very thin.

When first using it I noticed that the angle of the hot end was not level and the longer left the worse it got. after 15-20 mins even with the fan it's impossible to print anything or it'll be grinding along the print bed.
Re: Best hot end
November 12, 2012 12:16PM
I've been using a 0.25mm version of this hotend for three months and it performs perfectly. As long as you make sure to secure it with both of the support rods AND the 3mm grub screw, you'll be good to go.


--

Charles S.
Software Engineer
Prusa Mendel I2, RAMPS 1.4, Marlin 1.0 R2, Pronterface, Slic3r
Re: Best hot end
December 11, 2012 11:23AM
I've tried it and it just broke.
So what happened?
pla came out through the labyrynth sealing and some how on the bottom so everywhere where two ptfe peaces are put together and its unrepearable.
So I can't recommend it at all.
other things apart from it preaking down.
its gigantic and steals a lot of z travel.
it drops plastic.
but its cheap.
Re: Best hot end
December 11, 2012 11:33PM
Yep exactly the same thing happened to me! It just holds the heat in, gets hot all the way up and pressure builds.

I've gone with an Arcol v 4 and it's outstanding. Spend extra and get the Arcol [shop.arcol.hu] well worth investing in Laszlo's Hobbed bolt as well.

Edited 2 time(s). Last edit at 12/11/2012 11:43PM by zephyrdaz.
Re: Best hot end
December 18, 2012 08:11AM
I purchased two of these because it was an insignificant cost increase over purchasing one and a friend of mine was interested in making his own printer. The first one worked for about 6 months but eventually the extrusion force got too high. I managed to pull the filament out and it had ballooned into a void that must have gradually expanded inside the hotend. I used the second nozzle and it worked fantastically for about 2 weeks before the same thing happened. I didn't want to fork out for a new hotend so I drilled out one of them to a larger diameter and inserted a ptfe liner in it. It's now been working pretty well and shows no sign of failure, I also have a fan blowing over the top part of the hotend. I will get a better end at some point but this modified one does a decent enough job!

All decent hot ends ate just a bit too expensive to make me upgrade something that works pretty well...
Re: Best hot end
December 18, 2012 05:00PM
From my experience I can tell you that nothing concerning reprap compares to the feeling of having built your own hot end. That feeling is simply awesome. winking smiley


Detlef

 
Excalibur Hotend
     
reprapzone.blogspot.de

Re: Best hot end
December 19, 2012 03:20AM
I'm glad to hear that someone else makes their own hotend - seems to be a minority interest! And as you say, building a working hotend from scratch is a satisfying business. I'm still trying to understand some of the subtleties of the design - shape of the outside of the nozzle for optimum print quality, for example - but I still get a kick out of using a home-built hotend. Mine is a development of the "Adrian" design, modified for easier construction and now incorporating twin heater resistors for faster and more powerful heating. Also recalibrated the thermistor tables in Sprinter and tuned the PID parameters to suit my design.

I really must turn some of my back-of-the-envelope sketches into CAD drawings so that I can make another one some day when I've lost the originalssmiling smiley

- Brian
Re: Best hot end
April 16, 2013 01:22PM
I also made my first hotend, based on the J-head MK3. It performed well for many months until a thermistor failed and the PEEK part melted. Then, as I was trying to clean up the mess, I ended up damaging the nozzle orifice. But I'll make another, as this was very reliable.

I also bought a J-head MK4, but found it less easy to work with, and much more prone to clogging than my own interpretation of a J-head.
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