New Mini Hotend!

Fair enough I apologise too. I think if I had a mini hot end I wouldn't mind a second fan for print cooling there would be space and mass available for both

Edited 1 time(s). Last edit at 03/24/2016 02:18PM by DjDemonD.

@Chris

We have some pictures on the product page on our website on how it's mounted. It's mounted simply by using 2 M3 screws.I believe the push-fit is threaded 3.20mm deep into the heatsink.

Also note that you will have to PID tune the heater as the resistance is planned to be manufactured at 3.6-4.4 ohms. For smoothieware this is very easy as it has auto-PID tuning that we've tested with and works great.

You wait all year for a new mini hotend then a few come along at once.

and it's black!
[www.3ders.org]

Edited 2 time(s). Last edit at 03/31/2016 01:09PM by MechaBits.

@MechaBits, that hotend will not perform as well as one may think. The bottom and top portion of the fan is blocked off due to the square nature of the aluminum heatsink. It will only cool it on the sides. Our Mini hotend cools the heartbreak itself because the fan sticks out under the heatsink a bit.

I would also compare the size and weight.

Is that a 20mm fan you are using Shai? They seem to be hard to find in 12v.

@JamesK We were originally going to use 20mm fan, but we're going with 25mm. Yes they are hard to find and expensive.

The center part of the fan has no cooling effect, only the sides/circumference but a few standoffs wouldnt hurt with airflow
This is the mini fan I was talking about earlier, wonder where they come from.


Edited 1 time(s). Last edit at 03/31/2016 01:44PM by MechaBits.

Hi shai, just bought one of these from you and got it yesterday. I wondered if I might ask a few questions to help to get it setup?

Is the fan supplied 12v? or 5v? I've got it running at 12v its noisy, but effectively cooling the heatbreak so that's fine. In fact since I am manually calibrating the printer the noisy fan actually helps as I can hear when the nozzle touches the bed which is faster than the paper test.

What thermistor are you using? Can you link me to the datasheet for it? Is there a thermistor table for Marlin? If not would you like me to make one?

I am sure there is some documentation for this device on line somewhere but I haven't found it yet. Why not put something in the envelope with the hot end - I have a fair bit of experience with 3D printers but if I was a total noob there would be lot of things I could have gotten wrong installing it. Like wiring the thermistor to the heater etc...

I am printing with it and its working very well, so quite impressed with it given its superbly small size.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Also what other nozzles are available?

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

If anyone needs one I just made a marlin thermistor table for this hotend, using a k type thermocouple.

If not perfect but will get you to around 3 degrees of the set temperature.
If you're using Marlin RCbugfix Rc7 you can add this table. Make sure if using a later version there is not already a table 14, if so renumber it where the green text is below, upload and select your new table in configuration.h for temp_sensor_0

#if ANY_THERMISTOR_IS(14)
// Semitec 104NT-4-R025H42G B25/85=4267 +/-2%
const short temptable_14[][2] PROGMEM = {
{ 48 * OVERSAMPLENR, 280 },
{ 51 * OVERSAMPLENR, 270 },
{ 54 * OVERSAMPLENR, 260 },
{ 59 * OVERSAMPLENR, 250 },
{ 63 * OVERSAMPLENR, 240 },
{ 70 * OVERSAMPLENR, 230 },
{ 76 * OVERSAMPLENR, 220 },
{ 85 * OVERSAMPLENR, 210 },
{ 96 * OVERSAMPLENR, 200 },
{ 108 * OVERSAMPLENR, 190 },
{ 127 * OVERSAMPLENR, 180 },
{ 177 * OVERSAMPLENR, 160 },
{ 262 * OVERSAMPLENR, 140 },
{ 366 * OVERSAMPLENR, 120 },
{ 510 * OVERSAMPLENR, 100 },
{ 635 * OVERSAMPLENR, 80 },
{ 801 * OVERSAMPLENR, 60 },
{ 870 * OVERSAMPLENR, 50 },
{ 928 * OVERSAMPLENR, 40 },
{ 967 * OVERSAMPLENR, 30 },
{ 989 * OVERSAMPLENR, 21 },
{ 1008.7 * OVERSAMPLENR, 0 }

};
#endif

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Hi,
I need help with the mini hotend. I need a table for the 104NT-4-R025H42G thermistor management.
I tried the suggestion of DjDemonD recommends this configuration:

#if ANY_THERMISTOR_IS(14)
// Semitec 104NT-4-R025H42G B25/85=4267 +/-2%
const short temptable_14[][2] PROGMEM = {
{ 48 * OVERSAMPLENR, 280 },
{ 51 * OVERSAMPLENR, 270 },
{ 54 * OVERSAMPLENR, 260 },
{ 59 * OVERSAMPLENR, 250 },
{ 63 * OVERSAMPLENR, 240 },
{ 70 * OVERSAMPLENR, 230 },
{ 76 * OVERSAMPLENR, 220 },
{ 85 * OVERSAMPLENR, 210 },
{ 96 * OVERSAMPLENR, 200 },
{ 108 * OVERSAMPLENR, 190 },
{ 127 * OVERSAMPLENR, 180 },
{ 177 * OVERSAMPLENR, 160 },
{ 262 * OVERSAMPLENR, 140 },
{ 366 * OVERSAMPLENR, 120 },
{ 510 * OVERSAMPLENR, 100 },
{ 635 * OVERSAMPLENR, 80 },
{ 801 * OVERSAMPLENR, 60 },
{ 870 * OVERSAMPLENR, 50 },
{ 928 * OVERSAMPLENR, 40 },
{ 967 * OVERSAMPLENR, 30 },
{ 989 * OVERSAMPLENR, 21 },
{ 1008.7 * OVERSAMPLENR, 0 }
};

But in my case I have more than 30° of difference. With many difficulties I run the PID Autotune (i set the #define MAX_OVERSHOOT_PID_AUTOTUNE 40 !!)... the printer still does not print, when the temperature is set to 195 ° printing does not start because the temperature is not stable and oscillates between 182 ° and 204 °

>>> M303 H0 S200 C9 U1
SENDING:M303 H0 S200 C9 U1
PID Autotune start
Hotend: 0 Temp: 200.00 Cycles: 9 Apply result
bias: 45 d: 45 min: 192.03 max: 222.81
bias: 41 d: 41 min: 185.95 max: 216.88 Ku: 1.69 Tu: 21.23
Classic PID
Kp: 1.01 Ki: 0.10 Kd: 2.69
bias: 36 d: 36 min: 191.30 max: 210.90 Ku: 2.34 Tu: 16.22
Classic PID
Kp: 1.40 Ki: 0.17 Kd: 2.84
bias: 35 d: 35 min: 191.88 max: 208.98 Ku: 2.61 Tu: 16.52
Classic PID
Kp: 1.56 Ki: 0.19 Kd: 3.23
bias: 35 d: 35 min: 192.08 max: 208.64 Ku: 2.69 Tu: 16.81
Classic PID
Kp: 1.62 Ki: 0.19 Kd: 3.39
bias: 35 d: 35 min: 191.46 max: 208.47 Ku: 2.62 Tu: 16.52
Classic PID
Kp: 1.57 Ki: 0.19 Kd: 3.25
bias: 35 d: 35 min: 191.98 max: 208.01 Ku: 2.78 Tu: 16.22
Classic PID
Kp: 1.67 Ki: 0.21 Kd: 3.38
bias: 35 d: 35 min: 192.19 max: 208.98 Ku: 2.65 Tu: 16.81
Classic PID
Kp: 1.59 Ki: 0.19 Kd: 3.35
PID Autotune finished! Put the last Kp, Ki and Kd constants from above into Configuration.h or send command M500 for save in EEPROM the new value!
Kp: 1.59 Ki: 0.19 Kd: 3.35
>>> m500
SENDING:M500
Echoettings Stored (2013 bytes)

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Gianluca

Kossel K2 [ø 0.4 - 1.75] | Ruramps 1.1 | TMC2100 | MK4duo | KISSlicer
Website - Thing

Have you got a reliable thermocouple? If so make your own table. In configuration_adv you can get marlin to display adc values. All you need to do is heat up slowly and map the temps shown on the thermocouple to the adc values. Set more readings at 180—240 for better accuracy. It's a bit tedious.

It's sound like a tuning issue also as its oscillating rather than being stable but at the wrong temp. The thermistor is only tucked under the silicone cover, you could replace it with a known thermistor you trust.

Edited 1 time(s). Last edit at 02/22/2017 09:49AM by DjDemonD.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Quote
DjDemonD
Have you got a reliable thermocouple? If so make your own table. In configuration_adv you can get marlin to display adc values. All you need to do is heat up slowly and map the temps shown on the thermocouple to the adc values. Set more readings at 180—240 for better accuracy. It's a bit tedious.

It's sound like a tuning issue also as its oscillating rather than being stable but at the wrong temp. The thermistor is only tucked under the silicone cover, you could replace it with a known thermistor you trust.

I have a Deltaprintr Mini Hotend

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Gianluca

Kossel K2 [ø 0.4 - 1.75] | Ruramps 1.1 | TMC2100 | MK4duo | KISSlicer
Website - Thing

Yes I know. What I mean is if the table I made doesn't match your thermistor, maybe it's a slightly different unit. Make your own table using a thermocouple. Each temperature needs an adc value.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

these are the measurements ... how I act on the code?

PRINTRUN | THERMOMETER

50° | 34.9
55° | 37.6
60 | 40.4
65 | 43
70 | 45.7
75 | 48.4
80 | 50.3
85 | 53
90 | 54.8
95 | 56.5
100 | 58.5
105 | 60.9
110 | 64.5
115 | 67.1
120 | 69.2
125 | 70.8
130 | 76.2
135 | 78.4
140 | 79.3
145 | 81.9
150 | 84.6
155 | 88
160 | 90.8
165 | 93.1
170 | 93.8
175 | 96.2
180 | 99.1
185 | 100.7
190 | 106.1
195 | 104
200 | 105.6
205 | 107.5
210 | 108.6
215 | 109.6
220 | 111.6

Edited 1 time(s). Last edit at 02/22/2017 12:02PM by karnhack.

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Gianluca

Kossel K2 [ø 0.4 - 1.75] | Ruramps 1.1 | TMC2100 | MK4duo | KISSlicer
Website - Thing

There is a lot of information here:
[www.thingiverse.com]

The firmware turns the resistance of the thermistor into an ADC (analogue to digital) value from 0-1023.

The thermistor table allows the firmware to interpret the temperature from an ADC value.

In marlin if you look for these lines in configuration_adv.h

//Show Temperature ADC value
//The M105 command return, besides traditional information, the ADC value read from temperature sensors.
//#define SHOW_TEMP_ADC_VALUES

Uncomment "define show_temp_adc_values" and upload firmware.

Then pronterface will show the ADC value at a given temperature.

All you need to do is heat the hotend, measuring the actual temperature with a k-type thermocouple (do not use an IR thermometer they are nowhere near accurate enough and heater blocks are reflective and give false readings) and record the ADC values for each temperature, consider doing every 10-20 degrees up to 180 degC then every 5 or 10 degrees up to 250 degC so that you have accurate readings in the typical printing range. Then make your table by following the same format as the other tables - in thermistor_tables.h or if using later Marlin make a new thermistor table file for your table.

This should get you reasonably close temperatures displayed to actual temperatures.
After that autotune.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions