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I dont know elsewhere but in europa those rods are really easy to find, under the stubb moniker, and they make a strong difference, both in precision and lifetime.
Any industrial supplier will have them in centerless grounded form. In France, even harware stores for DIY often carry them.
this is what I'm speaking of, about 10€/m but you can find cheaper :
The stainless version (inox) is 4x
by
alj_rprp
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General
buying stainless steel rods is the most common and most costly error you can make !
Stainless steel is not hard enough even in the best refs like 316L (eu denomination).
What you need is good chrome alloy like 100C6 or Cf53 tempered to 62-63 HrC and grinded not simply extruded.
Chrome alloy is costly, about 3x time the price of a standard steel rod, but guaranteed to be perfectly straight and
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alj_rprp
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General
If it dont moves on its own weight it can be a very good one with preload or a bad one, it means nothing much by itself. Same for making some noise, the very best ones are mostly silent but the noise is usually from the return track so not a big deal.
What you can check is how smooth the motion is once it started and how constant is the force needed, but it is only meaningfull if you have good,
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alj_rprp
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General
For the power, 12V 5A is fine if you dont have a heated bed to power the card itself. For the bed, you need an additional12V 11A minimum. this can be the same or a separate supply.
For the drivers, look there for all pololu versions :
except #1183 they are all compatibles with ramps 1.4.
A4988 (#1182) is the basic one and is fine with most prusa motors which are NEMA 17. You may need to add s
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alj_rprp
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Reprappers
Hmm That was a price with 20.6% VAT included which need to be discounted if exported to US
130€ *0.8 / .77 = 135$.
And this is a kit where everything is already soldered including the pololus.
other suppliers :
on reprapworld.com, pololus not soldered no VAT
ramps 1.4 assembled 46.21€, mega2560 29.99€, 4 pololus 45€
excluding VAT total = 121€ / 157 $
on reprap.cc, pololus not soldere
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alj_rprp
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Reprappers
180$ is a very steep price for a ramps 1.4, I think.
A complete kit including an original arduino mega, 4 pololus and 3 opto endstops is 130€ here from a supplier which has not the lowest prices but good quality and including a 20% VAT.
So either there is more stuff included or I think you can find a much better deal.
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alj_rprp
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Reprappers
COM19 ça marchera pas. arduino exige un port <8 (adressage 4 bit), windows reserve 0,1&2 donc il faut que le port soit entre 3 et 7.
Mais si les drivers sont installés correctement, quand la carte est reliée vis le cable USB, un port valide (donc <8) doit apparaitre dans le gestionnaire de périph windows et c'est celui ci qu'il faut utiliser. Par contre attention de se brancher directe
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
Ces gens là distribuent pour l'industrie en grande plaque :
sinon ça se trouve en magasins d'art graphique. Forcément c'est plus cher au détail.
le dibond s'appelle aussi alucobond ou alupanel, c'est tout des produits similaires (la partie plastique change).
Sinon ça se découpe très bien au jet d'eau, à la scie sauteuse et ça se fraise et se poinçonne.
A ma connaissance au laser, c'est pas
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
faire découper. Ce genre de pièce peut toujours se déformer pendant le transport donc s'approvisionner localement est mieux. Une fois montée, il n'y a plus de risques.
Un truc si on connait pas de découpeur, s'adresser à une boîte qui fait des enseignes sur mesure, ils pourront soit le faire soit renvoyer sur un découpeur (laser ou jet d'eau).
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
Attention, j'éviterai à tout prix la variante médium ou MDO sur la i3. Ce n'est pas un matériau suffisament stable à la chaleur, l'humidité et au vieillissement. Au pire un contre plaqué marine serait ok mais à un coût équivalent à l'alu.
Aluminium parfait, et le dibond (sandwich d'acrylique et de 2 feulles Alu ep totale 3) bien et nettement moins cher.
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
Prusa i3, mendelmax, mendel 90 sont imho les 3 options les plus performantes, mais faut tout sourcer soi-même dans ce cas pour tomber sous les 600€ (attention aux frais de port, ça augmente très vite la facture).
Tu peux trouver des kits prusa i2 complets pour moins de 600€, c'est aussi une bonne machine, simplement vérifier la réputation du fournisseur.
Pour la mienne, j'ai opté pour un kit
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
Too many layers is indeed bad with PTFE tape.
I dont really know for high temp, but in hydraulic use, the rule of thumb is to never exceed 2 1/2 turns, preferably do 1 1/2. Also, you must apply the tape in the reverse direction of the thread, so that the tape is stretched when locking it.
If you want more PTFE there you can use compound, but that is even more sliperry.
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alj_rprp
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General
Traumflug Wrote:
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> Backlash Wiki
>
> Wikipedia is wrong on this one.
Yes, but not for the reason you state.
> The stiffness of a zero backlash system is a
> different topic. For example, ball bearings are
> much weaker than bushings, because they have a
> point contact, only. With load, the balls sink
> into the r
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alj_rprp
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General
> In all seriousness though, I genuinely think PEEK
> is a possibility - our efforts to get some made
> for us have so far been in vain. However we are
> looking into self-extrusion of granules to get
> around this. I would also love to print FEP,
> (A fluoropolymer like PTFE in many ways, but can
> be melt processed) would be amazing for bearings
> and such, but I imagin
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alj_rprp
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General
Printing the peek tube for a J-head would be quite a sacarstic jab
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alj_rprp
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General
billyzelsnack Wrote:
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> I wonder if it would be possible to create a
> printing friendly articulation of this actuator.
>
>
> Maybe useful for a scissor or other setups too..
>
This kind of mechanical jack works extremly well, but there is several issues for use in a printer :
- The original metal parts are expensive d
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alj_rprp
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General
Si c'est une USB, c'est une certitude que la reprap n'est pas sur le com1, c'est un port réservé que l'USB ne peut utiliser.
Normallement c'est au moins sur le com4.
Les drivers de l'arduino (ceux correspondant au modèle exact de carte) ont ils été installés ? sur windows c'est indispensable. le port apparaitra dans les menus arduino
Ensuite, dans le programme arduino, choisir le bon port dans
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
40W on 12V, that is 3.3A and with PWM on, only about 60% duty for 200°C.
steppers are 1.6A max but also not on 100% duty. so that falls under the 5A at 100% duty.
Classic resistors are 6.8 Ohms so give just below 2 amps. And with less wattage, they have a higher duty, because the heat to furnish to the head is the same.
In any case that works flawlessly here. The circuitery may limit current t
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alj_rprp
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General
thanks, but I'm in europa.
the cartridge fit in the resistor hole, it is just a bit longer.
My J-head has a grub screw to fix it. I used fire cement to insure that there is good thermal conductivity both on cartridge and thermistor.
by
alj_rprp
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General
I have a similar one in 6mm dia length 24 mm on my J_head. Works flawlessly but it is mandatory to be in PID mode.
In bang-bang mode, it heats so quickly that it would overshoot by 12°C or more. In PID mode, pronterface reports regulation to be less than 1°C so it is perfect. came with very nice wires long enough to go directly to the ramps
A 12V 30W version is sold by some german vendors so wo
by
alj_rprp
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General
dont use stainless rods. It is costlier and inferior quality for that purpose.
You need high chrome steel, grounded, polished and hardened at least to 54 Hrc, preferably 60 Hrc. Stainless is way lower hardness.
Often marketed as stubb rod, technical euro designation is 100C6 or 100CrC meaning it is 1% Carbon and 1.5% Chrome.
No risk of rusting if oiled.
These rods have also a straightness guaran
by
alj_rprp
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General
Dans pronterface, l'imprimante étant connectée, il y a une zone de texte tout en bas à droite.
saisir M303 S195 là
appuyer sur le bouton send.
l'extrudeur va faire plusieurs cycles de chauffe et au final te donner 3 valeurs pour P I et D.
Je conseille de faire cela au 2 fois d'affilée.
Problème si tu éteind l'imprimante maintenant, tu perds le réglage, donc il faut reflasher le firmware.
quitte
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
Les dernières j-head utilisent un thermistor table 7, pas 1 parce que les 1 sont devenus durs à trouver.
Les tables 1 (epcos) ont les 2 broches du meme côté, les 7 (ref 135-104QAD-J01) en ligne comme une resistance.
le chiffre après la temp est l'indice de chauffe, tu chauffes 145/255 % du temps. cette indice varie avec la regulation.
l'autotune a t'il été fait (important !) ?
Sinon M303 Sxxx
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
En premier vérifier ?_HOME_DIR est ok pour chaque axe. ça définit ou se trouve le 0 de l'axe
Si le homing se passe bien normalement c'est bon.
Ensuite ajuster ?_MAX_LENGTH
Ca se trouve dans sprinter/configuration.h et il faut reflasher le firmware si on modifie :
//-----------------------------------------------------------------------
//// ENDSTOP SETTINGS:
//------------------------------
by
alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
185°C à 40mm/mn avec une J-head je trouve ça bas.
La mienne (Mk V buse 0.4 aussi) est réglée à 202°C pour que ça se passe bien. Il faut que je sois au dessus de 195°C pour que la pression d'extrusion se réduise beaucoup et l'extrusion soit parfaitement régulière. Maintenant la valeur lue depend du thermistor et de sa position mais vérifie qu'à vide, ça extrude sans forcer.
Il faut serrer aussi l
by
alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
like 978-109BC12GC7-1 on mouser.com ?
For equivalent size and price, you can find high speed frontal fans with better air flow in a ratio of 3x or 4x. But it is true that such blowers are not as much impeached by backpressure, so YMMV.
And blowers tends to be noisy.
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alj_rprp
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Reprappers
Original trapezoidal profile is US ACME 29° thread in late 19th century.
Nowadays when someone speak of trapezoidal profile it is usually the 30° metric profile, but the ACME profile is still widely used worldwide.
The origin of the ACME thread is that the previous leadscrew profile, squared thread, is difficult to manufacture as the smallest deviation will bind it.
by
alj_rprp
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General
very easy if you do it in a place that dont have to clear any pulley or idler on the full stroke, very difficult otherwise.
To join 2 belts simply cut a seven teeths strip reversed and use 2 electrical cable ties to attach on each belt, just insuring that play at teeths is taken out.
If you have to clear a pulley, you cannot do that, and while there is methods for bigger belts, they are not po
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alj_rprp
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Reprappers
Thylakoide Wrote:
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> Thierry,
>
> Ou as-tu acheté ton comparateur? 15€ c'est
> vraiment pas cher !
9.27 € HT chez otelo.fr. A ce prix la c une merde chinoise, mais ils ont de la marque pour 30€
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alj_rprp
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RepRap Groupe d'Utilisateurs Francophone
At 23L /100m check some euro distributors. no risk of import duty, VAT already included and a 100m spool will be around 22-25€ or less. I use formfutura and i find their PLA good, but there is several others that are cheaper. The 15% difference between moneys will cover shipping if you group your order a little (shipping 20€/5kg down to 34€ for 20kg).
Simply when seing price below 20€, be caut
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alj_rprp
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General