Arcol blog Just another RepRap weblog

3Apr/140

Arcol.hu hotend v4 for Rapman

Arcol.hu hotend v4 adaptation for Rapman machines

The assembled Rapman filament drive with the arcol.hu v4 hotend during extruding:
flickr:10075997614

Get it here.

Preamble

As you may be aware, back in 2010, the v3 version of the hotend (the PEEK based, so not the v4 all metal one),
was compatible mechanically and electrically with Rapman machines:
flickr:6132800160

Starting from v4, the thermistor was intially switched to 104-GT2, which discontinued mechanical compatibility with the Rapman:
flickr:8090861787

I then migrated to a Honeywell thermistor, which enabled me to leave out the fire cement, shown here:
flickr:8417232071

These changes to the v4 hotend made it technically superior to the old one, and also way faster to assemble. However, it was neither mechanically nor electrically compatible with Rapman machines.

Recently, I have been approached by two people to get manufactured a fully compatible hotend for the Rapman. Two people are almost a crowd! :)

So with that in mind, I think I came up with a pretty good solution:
flickr:10056587836

In detail

The length of the original v4 hotend was short by design,
however to maintain mechanical compatibility with the Rapman,
it needed a longer (73mm tall) hotend.
Pictured here is the assembled unit complete with nozzle, barrel and heatsink:
flickr:10056463225

The new heatsink consists of two parts:
- The heatsink itself, which is 15.5mm longer than the standard one
- a disk, which goes on top of it, what you can mount on the Rapman machine using two M5 bolts.

flickr:10067942406

The lower part of the hotend needs no modification, except it is
reverted back to the firecement version for using the 204-GT thermistor.

Summarizing the modification is basically a reworked heatsink and mounting plate.

I do hope it will serve well all the rapman users, who are still out there.
flickr:10056464214

For reference, see this v3 hotend assembly page.

Some exotic combination

I will keep around the older heater block design which suits the
204-GT2 thermistor (and 104-GT2) because it is necessary for the Rapman.

The new and old heater blocks are compatible mechanically, so you can use the normal hotend with the older heater block if you need it for some reason.

Likewise you can get the Rapman version with the new heaterblock, if you have an exotic machine where this hotend suits better mechanically.

Testimonials

To date, I have only delivered two kits. Of these, one has
been installed and tested with very positive feedback.

Here is a quote from Rob:

I would like to add that the Hotend Unit you supplied is performing like a champion and has surpassed all of my expectations on its performance and reliability to date.
— Rob

How to get it

You have four variations to choose from:
- Assembled with 0.35mm nozzle
- Assembled with 0.5mm nozzle
- Unassembled with 0.35mm nozzle
- Unassembled with 0.5mm nozzle

1Dec/12Off

Recommended extruder setup

Introduction

Grab the complete setup here.

Many people ask me what setup I am using with the arcol.hu v4 hotend,
or what setup I recommend for it.

I bit the bullet, and I wrote this detailed article.

I am always trying to push the envelop of 3D printing, therefore my machine
is evolving all the time, so you can expect more articles in the future:)

The extruder shown here will also be available as a kit through the website.

This recommendation is for 2012 december, although it could have been built since around 2012 march.

Partlist (with pictures)

Arcol.hu hotend v4.1.1:
flickr:8090861787

Go grab one! or Grab the complete setup!

Arcol.hu hyena v1.1:
hyena_v1.1_m.jpg

Go grab one! or Grab the complete setup!

M8 nut with M3 grubscrew:
m8nutm3_withandwithoutm3_m.jpg

Go grab one! or Grab the complete setup!

Arcol.hu spring kit:
flickr:8091226753

Go grab one! or Grab the complete setup!

40mm fan:
flickr:8154959171
Are you wondering why is a cap there?: Maglev carriage fan

Wade's accessible extruder body:
flickr:8208843193

Carriage with 2 fan holders:
flickr:8209932764

Satchet of nuts and bolts:
flickr:8218045926

608 bearings and linear bearings (LM08UU):
flickr:8216417635

Just to see it in perspective:)
flickr:8209975430

Downloading the .stl file of the RP parts

All of the RP parts, are from thingiverse.
However I have modified almost all of them. I will publish one .stl file per
week on thingiverse, referring back to the original thing and its author.

Assembly of the carriage

Here is the carriage one more time:
flickr:8209932764

The linear bearings goes in there:
flickr:8208845201

The two fans on the sides, and it looks like this when mounted on a machine:
flickr:8193844195
(Note: There is one bar clamp missing from the above picture)

The modell of this print is available on thingiverse, as thing:39923. It is basically a touchup of thing:15534, which is based on thing:9869.

Idler

This is the idler of the Wade extruder pusher:
flickr:8209931886

It has an integrated guide, so you dont need the grooved 608 bearing,
to guide the filament, its mere cost saving.
You can still have the grooved 608 bearing, it does not make things worse, this idler just duplicates the grooved 608 bearing feature.

The modell of this print is available on thingiverse, as thing:39933. It is basically a touchup of thing:17030 and thing:6703.

I have RP parts available in three different colors: white, green and black.
Here is a comparison between green and white print:
flickr:8208844213

Gears

Here is the gears I use:
flickr:8208843761

You may be wondering why I am not using herringbone gears.
Herringbone gears run a little quiter, and have a tiny bit less backlash.
Also they can handle higher torque.

However it does not affect print quality.
The filament has a backlash due to its inertia, and we compensate
for backlash anyway. It has the same number of teeth, so no additional
resolution either (not that we need it).

But the main reason is that it is more troublesome to print out, for no real
advantage, so I kept the traditional spur gears. You can print a
herringbone if you wish as an upgrade.

Wade pusher (extruder upper body)

Here we go:
flickr:8209877584

It is a modified Accessible Wade extruder, mainly the holes were adjusted.
It is more accurate and compatible with
v4 hotend.

Here is how the gears, idler and wade upper body will come together:
flickr:8208842179

The complete setup

The complete extruder assembled with carriage. Everything mounted:
flickr:8209976536

You can see the setup is standing on two M8 nuts, so the
hotend is lower by just enough distance then the two fans.
It is optimised for the minimum height, so you have the
maximum printing height possible*.

Here are some more pictures, it is kind of rotating:)
flickr:8208892595
flickr:8209975932
flickr:8209977016
flickr:8208890713
flickr:8209978038
flickr:8208891643
flickr:8209978962

History

You could have build this extruder setup from about february of this year (2012).
If someone would have published this extruder setup back in time, it
would have saved me some unnecessary circles.
So I hope you (dear Reader) find this article equally useful,
what I would have found it, if it was existed back then.

Printing quality

If you want to check what is possible
with our v4
hotend in regard of printing quality, or you want a trouble free
extruder setup, then go get one!

As a remainder, here it is the wade pusher printed in white:
flickr:8208789761
(the white is the easiest to photograph, every irregularities are shown)

Im fairly happy with the overall printing quality, you can see it as
our current state of the art at 0.3mm layer height.

No worries, even finer layer height is possible, so it is not the
limit of what v4 is capable of.

Availability

Grab the complete setup here.

I think Im able to print one full set per week, and for start I have
3 full sets. I know it is limited, but it is not intended for general
public, just for the quality enthusiastic and those who want
a working printer first and a DIY machine second.

I have some leftover pictures, which would be too bad to miss out:)
flickr:8209929910

And even moar:
flickr:8208788749

—-
I change slightly the commenting policy. I will close the commenting after a week of the date of publishing to prevent spams leaking through.

But in all occasion, please prefer the mailing list.

After the above deadline, any further discussion can only happen on the mailing list, in this thread.

18Nov/12Off

Maglev carriage fan

Why do you need a fan?

As many of you may know, I have been using a double carriage fan (modified thing:9869) for my printer.
flickr:8193844195

If only the hotend needed the air movement,
a single carriage fan would suffice, yet I get better results with double carriage fan.

So first and foremost the print itself needs the fan.

Buying fans for the carriage

Choosing the right fan is not easy. The ideal fan must be able to be driven directly from a PWM output of the RAMPS.

Many fans are not capable of be driven from a PWM output,
so it's mostly a hit and miss when buying small fans.

Why is a MagLev fan cool?

Well, the magnetic levitation itself is cool:) Also it is more efficient per watt (has more air blow power) than a ball bearing or bushing fan.
In my case the ball bearing fan can blow a lit match from 14 cm away, while the MagLev fan can blow it out from 41 cm(!) away.
So roughly 3 times more blowing power.

What to do if the fan is not able to be driven from PWM output?

Modify it like this:
flickr:8154957239

I discovered my Maglev fans are not able to be driven from PWM output, they only work
with M104 S255, and not any value from 0-254.
Issuing a command less than S255 makes a strange pitch noise instead of turning the fan.

So I started experimenting, and I figured that I only need to add a small capacitor (any electrolite type capacitor works) between 4.7 uF and 100 uF.
(YMMV and also warning: some type of fans does not rotate even with this modification)

Also watch out for the polarity, here there is a pic showing how I modified my two maglev fans:
flickr:8154959171

Aesthetics

I think the capacitor is small enough not to destroy the aesthetic looks of things:
flickr:8154961803

An example of these small fans on the carriage:
flickr:8154978444

(note the superbright yellowish green clamp in the background:)

—-
I closed down the commenting on this webpage due to the enormous number of penis enlargement suggestions.

If you have any thoughts to share about this article, please discuss it on arcol.hu's mailing list,
in this thread.

30Oct/12Off

Arcol.hu hotend v4.1.1.

History

For previous announcement please read here:
http://blog.arcol.hu/?p=1939

The v4.1.1 version

Im really proud to announce arcol.hu hotend v4.1.1:
flickr:8090861787

In a nutshell:
- v4.1. - aluminium mounting plate (that also means integrated setscrew in the heatsink)
- v4.1.1 - firesleeve

Aluminium mounting plate (v4.1.)

I replaced the wood mounting plate with an aluminium one.

Just to recall here is how the v4.0.5 looked like:
flickr:6360336939

Here is the v4.1:
flickr:8091010098

I also added an M3 setscrew, to fix the heatsink to the mounting plate
(prevent rotating the whole hotend at high speed).
flickr:8090965143

Also here is how the hotend looks after 6 months of printing:
flickr:8090969472

So the firecement is quite good solution, once it is applied.
flickr:8091008788

Firesleeve added (v4.1.1)

To prevent skin burn, protect heater block against fan blow, and last but not least looks awesome:
flickr:8091379242

Machine compatibility

This hotend is designed for reprap machines (or compatible).
However I had success reports from customers using in 24VDC system, like R2C2 electronics (you need different resistor, so definietly say it before purchase).

I would be really interested how others have mounted or adapted this hotend for their machine,
like makerbot.com or ultimaker.com.

If you happen to have a machine like the above, and you want assistance,
just drop me an email through preorder(at-arcoldothu.

Go grab one:
http://shop.arcol.hu/item/arcol-hu-hot-end-v4-unassembled-05
http://shop.arcol.hu/item/m8nutm3

—-
I closed down the commenting on this webpage due to the enormous number of penis enlargement suggestions.

If you have any thoughts to share about this article, please discuss it on arcol.hu's mailing list,
in this thread.

19Oct/12Off

Arcol Hyena v1.1

Available at: http://shop.arcol.hu/item/hyena

History (v1.0)

For previous v1.0 announcement, read here:
http://blog.arcol.hu/?p=1920
and here:
http://www.thingiverse.com/thing:22369

V1.1 update

This is a minor, but really handy upgrade to hyena.

At one end it has 6mm flats for wrenches. So no more pliers to holding while putting the big gear onto the shaft.

This is how it should be mounted (flat end is the opposite one from big gear):
flickr:8090962459

Here is a closeup of the two flat sides:
flickr:8091117901

Here is how you should put the big gear onto the hyena:
flickr:8091129897

Also here it is mounted on the extruder pusher:
flickr:8091151235

(Note the M8 nut with M3 grubscrew! It is *really* useful)

Hyena: http://shop.arcol.hu/item/hyena
M8 nut with M3 grubscrew: http://shop.arcol.hu/item/m8nutm3

—-
I closed down the commenting on this webpage due to the enormous number of penis enlargement suggestions.

If you have any thoughts to share about this article, please discuss it on arcol.hu's mailing list,
in this thread.

17Oct/12Off

Arcol.hu spring kit

Available at: http://shop.arcol.hu/item/spring-kit

This is a simple spring kit for the extruder pusher:
flickr:8091226753

Many people have trouble finding the right spring for the job, so
I decided I will offer the exact same springs, that I use on my own machine.
I settled to this spring after trying out more then 20 different springs.

The ideal spring is small, stiff, but not too hard to compress,
so the hobbed bar (hyena) does not bite into the filament instantly.

Also when you change the filament, the bolt is long enough so you do
not need to take it out completely from the extruder pusher.

Curious enough, how it looks mounted?:), here we go:
flickr:8091233070

Go grab one!: http://shop.arcol.hu/item/spring-kit

—-
I closed down the commenting on this webpage due to the enormous number of penis enlargement suggestions.

If you have any thoughts to share about this article, please discuss it on arcol.hu's mailing list,
in this thread.

14May/12Off

Arcol.hu hotend v4.0.5

Arcol.hu v4.0 hot-end for 3.0mm filament (works also for 1.75mm filament too).

It has been a long time since I announced v3.0.

The new features:

  • - Hot-zone is completely metal.
  • - high temp extrusion should be possible, like pp, hdpe, plexi, polycarbonate, nylon (hopefully, this will be confirmed within a month)
  • - shorter, more compact, a comparison photo between v3.0 and v4.0:
  • - easier to assemble
  • - reworked nozzle
  • - laping for wrenches on nozzle, on stainless steel, heatsink
  • - built for easy maintenance
  • - self cleaning (you can remove the hardened plastic using two wrenches:)
  • - built with dual extruder in mind
  • - mounting compatibility for the average/stock reprap hotends
  • - 100k thermistor (which seems to be a more common preference)

For assembly instructions please read here:
http://wiki.arcol.hu/arcol-hu-hot-end-v4-assembly

Regressions/future adaptations:
Dropped compatibility for Rapman, Makerbot. A new mounting needs to be designed for these machines.
For rapman a 200k thermistor also needs to be sourced to be electrically compatible.

18Dec/10Off

Guest article: Tiny’s first experience with Arcol.hu Hotend v3.0

It was announced as "really big", but is the Arcol.hu Hot-end v3.0 is that great?

22Nov/10Off

Blender broke – Epilogue

My article titled "Blender broke" drew more media attention, than anything I've written lately. This is strange, as much cooler things have been happening around me:) Many sites picked it up.

I later read on a forum (I've forgotten which one), that the printed replacement part will break as it could not possibly be as strong as the original one. That did had some truth to it...

14Nov/10Off

Self-hosting

When a compiler reach the state, when it can compiles itself, it's called self-hosting.
My Arcol.hu Hot-end v3.0 reached that state, and more:-)