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I improved the design, now it uses a real tap, it carve the teeth better and more quickly :
The device now split in two parts by a 1/4 turn mechanism te release the bobbed nut.
Result on a round steel nut :
by
Petrus
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Look what I made!
It was working with 20% current and the weak power supply, no ?
I also fried other chips by connecting or disconnecting a motor when the driver was enabled, it's not specific to the TB6560.
Yep, a 3A fast-blow fuse will be fine.
by
Petrus
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Controllers
I've put a 10kohms resistor and 100nf capacitor on the reset pin to reset the chip at startup. I also encourage you to put a fuse on the power.
As I said before, this chip doesn't forgive any error, so respect the power-on and power-off sequences, double-check connexions before switching the power on and do not connect or disconnect the motor when the chip is enabled.
Once you follow these recomm
by
Petrus
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Controllers
I use EMC2, a software cnc motion controller, it sends the step & dir signals by the parallel port, I set the pulse timing at 6000ns, 5000ns doesn't work
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Petrus
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Controllers
From the datasheet :
After VDD and VMA/B completely stabilizes at the rated voltages, the RESET and ENABLE pins can be
set High. If this sequence is not properly followed, the IC may not operate correctly, or the IC and the
peripheral parts may be damaged.
by
Petrus
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Controllers
0,33Ohms gives you 1,5A
20% of 1.5A = 0,3A
Uphase = 1,7Ohms * 0,3A = 0,51V
so it's OK
When the motor runs at 20% does it have torque or it barely turns ?
If it does not have torque, check the voltage on each wire and see if there is an output stuck at 0V
On my fried drivers it's always an output that is stuck at low state.
by
Petrus
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Controllers
Yep, total power = one resistor power * number of resistors.
For the diodes, I used to see diodes on other driver boards, but the TB6560 actually don't need them.
For future boards, I will remove the diodes and use the free space to add a fuse, it will be much more usefull.
by
Petrus
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Controllers
I found a usefull value table on this forum to choose the resistance and wattage you need :
Or you can do like me, by connecting 1ohms 1/2W resistors in parallel :
by
Petrus
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Controllers
The TB6560 needs resistors on the sense pins, if you connected them to the ground the chip will not limit the current, destroying itself if your power supply is not limited in current.
This trick can work only with motors designed to be driven without current limitation, with a higher coil resistance.
TB6560 are also very delicate, they don't forgive any errors, I fried one by connecting the mot
by
Petrus
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Controllers
I tested different shape of nozzle :
Round (acorn nut untouched), cone at 120° angle, and 90°angle
To test the nozzles, I printed A 60°overhang in PLA whith 0.1mm layer height :
The round nozzle is the worst, 120° and 90° give the same result.
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Petrus
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Plastic Extruder Working Group
There is still a little bit of warping, but it is far better.
Yes it's ABS, printed on glass with mat varnish for better adhesion, the heated bed was at 100°C during the entire print.
by
Petrus
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General
I printed the same object with and without the plastic bag :
Left : without bag, right : with the bag
The printed object is a sub-d cover I designed :
by
Petrus
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General
This is my new extruder design for the Heavy Mendel :
It's more compact than my previous extruder and mostly made with printed parts, the last one was made from milled parts.
The sub-d cover is also printed :
More details about the full-metal hot-end :
The heater is made from an M6 insert with the external thread removed :
The tip is an acorn nut drilled with a 0,5mm drill-bit :
and hamm
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Petrus
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Plastic Extruder Working Group
On my extruder I Use a 40mm fan salvaged from a server blade, it's very powerful for the size, it can inflate the bag even at low speed. The bag is also 25µm thin so it inflate easily.
by
Petrus
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General
I finally finished the wiring of the box :
Front :
Back :
by
Petrus
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Controllers
The wires are 0.69mm diameter, 49 strands stainless steel wire (fishing wire).
I tried with 7 strand galvanized wire, but it didn't pass the reliability test (100 cycles of this : ) the wire broke.
The bearings are standard 624ZZ bearing pushed inside an ABS printed part with a drilled nut inbetween as you can see on the pictures.
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Petrus
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General New Machines Topics
A heated chamber for the whole printer is not very practical, but what about a heated bubble ?
Here is an article from 2008 :
I re-created it using a freezing bag, inflated with the extruder fan :
The air inside the bubble is heated by the heated bed only.
I still need to improve it by sealing the bottom, but I think it's a very good idea.
by
Petrus
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General
This device automatically carve a brass nut to make a filament driving wheel for DIY extruders. Just install the nut, switch it on and it works by itself.
The carving tool is a simple stainless steel M4 threaded rod / hardened steel M4 screw shaped with a dremel to make the teeth :
The electronics is build around an NE555, it generates the step pulses for the stepper driver.
Stl files, sck
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Petrus
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Look what I made!
I built a new chuck to make the next hot-ends :
The motor is a blushless motor salvaged from a laser printer.
Stl files are available on the heavy Mendel wiki page :
by
Petrus
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General New Machines Topics
I used this more detailed model : and resized it to half its original size :
The print is 32mm high
Printed with 0.05mm layer height, it took 2h to print
White PLA
Infill feedrate : 100mm/s
Perimeter feedrate : 20mm/s
Infill : 0%
2 loops + perimeter
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Petrus
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Competitions
En utilisant une extrémité et le point milieu, la résistance est 2 fois moins élevée, donc le moteur pourra tourner plus vite que si il était connecté sur les deux extrémités.
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Petrus
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RepRap Groupe d'Utilisateurs Francophone
Exact, 6 fils : les points milieu est séparés, on peut l'utiliser avec un driver bipolaire.
5 fils : les points milieu sont communs il faut les séparer pour pouvoir l'utiliser en bipolaire.
Mais les moteurs unipolaires sont souvent utilisés avec une tension fixe, sans régulation de courant. La résistance des bobines est alors importante pour limiter le courant qui traverse le moteur. Et en l'uti
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Petrus
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RepRap Groupe d'Utilisateurs Francophone
Patrick 47 Wrote:
-------------------------------------------------------
> Concernant l'extrudeur, le pignon moteur à 15
> dents et le recepteur 54 dents, cela fait un
> rapport de 1/3, c'est pas trop mal.
> Le moteur est un "pas à pas", je pense que le
> pilotage permettra une bonne précision dans le
> déplacement du fil.
Sur mon extrudeur, j'ai une réduction de 1/6 avec une
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Petrus
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RepRap Groupe d'Utilisateurs Francophone
Comme l'a déjà dit Ghunt, faire bouger le plateau au lieu de la tête va fortement limiter l’accélération et donc la vitesse d'impression, de plus l'extrudeur type "bowden" avec moteur déporté a été conçu pour minimiser l'inertie de la tête. Ici elle est immobile il n'y a donc aucun avantage. Il faudrait mettre l'extrudeur à la place du plateau et visse-versa.
De cette façon seule la tête à faible
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Petrus
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RepRap Groupe d'Utilisateurs Francophone
Small ultrasonic cleaners does not have a heater function and the timer is very short. The smallest ultrasonic cleaner with heater function cleaner I found (Velleman VTUSCT5) has a capacity of 2l but the timer's maximum is 30min only. I don't have the space or the usefulness for a bigger one.
It seems the ultrasonic pulses are mandatory, so I think I will need to buy this 2l cleaner and hack it
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Petrus
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General
Can you try with the heater on but the ultrasonic switched off ?
If it works too, (it will certainely takes longer) we can build a dirt cheap support removal device by modifying a kitchen appliance.
by
Petrus
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General
I've uploaded the time-lapse of my print :
by
Petrus
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Competitions
I guess I'm the last minute entry
So there is my attempt, unfortunately not as good as rhysjones or richrap especially on that spot :
Printed in transparent PLA
Layer height = 0.2mm
Speed = 50mm/s
Printing time : 3h57
I've recorded the printing, I will upload the time-lapse tomorrow.
by
Petrus
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Competitions