McWire Successor

SebastienBailard Wrote:
-------------------------------------------------------
> Thanks sircastor!
>
> I've updated WolfStrap to point to the file:
> [objects.reprap.org]
>
> I may rename this thread the "WolfStrap (bootstrap
> RepRap) Group Design Party " in a day or so.

I've been working on this page over here:
[objects.reprap.org]
But it's not strictly that important. I've gone over the Google Translated version of Wolfgang's writeup. Some of it translates just fine, other parts not so well. I don't think my wife would appreciate me abandoning my McWire build for starting something new, but as soon as I'm finished with that (and have it handed off to my friend) I'm gonna see if I can come up with some solid plans and do a build. My guesstimate for constructing a Wolfstrap puts it under $100 for the total cartesian bot.

Downside: Not much of it is recyclable into a Mendel
Upside: If you have electronics and extruder stuff ready, I think you could get going in a weekend.

As for the thread name, my only hesitation is I don't want other McWire replacement ideas to be ignored or not posted because this morphs into a WolfStrap thread. Maybe we should start another thread?

Don't know if this changes anything for people, but last I looked you can get nylon acme-style lead screws (2.5mm pitch) for $5 a pop at [www.allelectronics.com] They seem to run smoothly enough; I can report back if anyone cares once I get my steppers mounted and working.

Lengertoes,
I agree with you completely. Even though I have not yet had time to start building mine, I am coming to understand the bits and pieces and way it operates better, and I am now confident that I can not only build it, but improve the documentation and performance.

MDF sounds like a good idea, but one advantage of the pipe or welded square tubing is leaving the front and sides open for the X-Y table to extend out further. MDF for the back would need a triangular section to brace it and keep it perfectly square with the X and Y planes. One way to do that would be to extend the bottom plate backwards, and add triangular gussets there. That would also become a good place to mount the electronics and power supply.

@sircastor

the parts without the Elektronik/motors cost <50€
and the Elektronik later goes to the Mendel.
My Construction is only temporarily.. only to make the Mendelparts. (Bootstrap)

i know, you cant translate my page with google. Thats the reason i do it in german.. I'm not rude... but i am not able to translate. My last English learning is >30 Years ago.

---

Mfg
Wolfgang

Aller Anfang war schwer - Wolfstrap

Reprap-fab.org

Erfahrungen kann man leider schlecht weiter geben, die muss man selber machen.

Stoffel15 Wrote:
-------------------------------------------------------
> @sircastor
>
> i know, you cant translate my page with google.
> Thats the reason i do it in german.. I'm not
> rude... but i am not able to translate. My last
> English learning is >30 Years ago.

Please don't take it as me complaining. I was mentioning it relative to building it. I'll probably follow your build process to some degree, but if there are any german speakers who could translate it, I think it would be a benefit to the group/community. I certainly appreciate your taking the time to document your work Wolfgang.

there are any german speakers who could translate it, I think it would be a benefit to the group/community

They may be too busy translating the rest of the wiki english->german.
[objects.reprap.org]

(or doing hardware research).

A good translation is hard work; I'm going to hold off on requesting that until WolfStrap-with-measurements is further along.

And at that point, I may use the blog to say "it's ready! come translate it".

That may "Please translate it into English" or "Please translate it into German"; it's all good.

sircastor Wrote:
-------------------------------------------------------
> Stoffel15 Wrote:
> --------------------------------------------------
> -----
> > @sircastor
> >
> > i know, you cant translate my page with google.
> > Thats the reason i do it in german.. I'm not
> > rude... but i am not able to translate. My last
> > English learning is >30 Years ago.
>
> Please don't take it as me complaining. I was
> mentioning it relative to building it. I'll
> probably follow your build process to some degree,
> but if there are any german speakers who could
> translate it, I think it would be a benefit to the
> group/community. I certainly appreciate your
> taking the time to document your work Wolfgang.


I could try to do a manual translation, although I am neither a native German nor English speaker, I think I can manage a decent translation, if there is a need.

oh... puur boy... but ich will help you if i can

---

Mfg
Wolfgang

Aller Anfang war schwer - Wolfstrap

Reprap-fab.org

Erfahrungen kann man leider schlecht weiter geben, die muss man selber machen.

> To reduce cost for first time 3D printer fans, I am also looking at making a single controller board for the whole machine

This sounds a lot like a project I have been working on. It will by a 4" x 3" PCB with all through hole mounted hardware. The main components will be 4 Pololu stepper drivers, an Arduino Mini and a couple MOSFETs. Here is my cost breakdown:

stepper drivers: 4 x $13 [www.pololu.com]
microcontroller: $19 [www.nkcelectronics.com]
PCB: $40 [batchpcb.com]
connectors, passive components and MOSFETs: $40 (this is just a guess)

That comes to $150 to make the prototype board.

---

---

Darwin clone, Gen 2 electronics, Arduino Duemilanove w/ AtMega328, 5D Firmware, Pinchwheel extruder
[www.codeerrors.com]

$40 seems awfully expensive for a bare PCB.

---

Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
BLOG - PHOTOS - Thingiverse

SebastienBailard Wrote:
-------------------------------------------------------
> there are any german speakers who could translate
> it, I think it would be a benefit to the
> group/community

I can translate from German to English.

For English to German you need a native speaker if you want the grammar to be correct.

Let me know when the page is complete and I will translate it to English (American).

---

Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
BLOG - PHOTOS - Thingiverse

> PCB: $40 [batchpcb.com]

I'd drop the PCB. Instead, use something like polulu's TB6612FNG Dual Motor Driver Carrier to drive the extruder heater. This can be parallelized to get 2Amp continuous/6Amp peak.

All the extra components, capacitors, resistors, etc. should come in under US$5, and can be soldered without adding extra PCBs, and also, should be solderable onto the existing pins on component boards.

@Sebastien- I have attempted to edit the wiki with no success.

Now I am concerned because I visited the WolfStrap page, clicked English and got the following permission error.

"You do not have permission to do that, for the following reason:
You are not allowed to execute the action you have requested."

To not be able to edit without permission I can see, but not be able to visit a translated page I don't.

Arvin Wrote:
-------------------------------------------------------
> @Sebastien- I have attempted to edit the wiki with
> no success.
>
> Now I am concerned because I visited the WolfStrap
> page, clicked English and got the following
> permission error.
>
> "You do not have permission to do that, for the
> following reason:
> You are not allowed to execute the action you have
> requested."
>
> To not be able to edit without permission I can
> see, but not be able to visit a translated page I
> don't.

@Arvin, the link is currently "out of action", Stoffel15 and I are working on a translation which, hopefully should be a tad better than the translation Google is capable of producing!

@Arvin, the translated page hasn't been created yet, so Wikipedia assumes you want to create the page, and if you aren't logged into the wiki with a known user account, you are not permitted to edit the page.

Stoffel,
Your English is FAR FAR better than I can speak any other language. And that is after studying spanish in grade school and 3 years of russian in college! You have absolutely nothing to apologize for. I just need to figure out how to get google to translate the page for me, cause the extruder graphic looks good!

Mike



Stoffel15 Wrote:
-------------------------------------------------------
> @sircastor
>
> i know, you cant translate my page with google.
> Thats the reason i do it in german.. I'm not
> rude... but i am not able to translate. My last
> English learning is >30 Years ago.

@ rocket_scientist
> cause the extruder graphic looks good!

is not my Graphic... There is a link to the page from...

---

Mfg
Wolfgang

Aller Anfang war schwer - Wolfstrap

Reprap-fab.org

Erfahrungen kann man leider schlecht weiter geben, die muss man selber machen.

@ bjbsquared: I did finally get to Lowe's and bought the smallest cable they had (1/16") and some 1" sliding screen door pulleys to try out making the cable auger....

Wrapping the cable around the 5/16"~8mm shaft I wanted to use(gives ~0.002"/step) made a permanent kink in the cable when I released it. I wrapped it around a 1/2"~12mm marker (gives mendel's 0.1mm/step) and it seemed to do much better.

0.1mm is accurate enough for the mendel. I wonder if it would be accurate enough to use the repstrap as a cnc to cut pcb boards.

I'll have to go back for some 1/2" rod to try again.

EDIT: replaced MOSFETS with Allegro A3977 stepper drivers

mccoyn,
to save money, I am planning on starting with a raw ATMega128 instead of an Adruino, and also A3977 stepper controller modules. That means 1 A3977 per motor for a bipolar stepper motor, 2 MOSFETS for the extreuder heater, and possibly one for a bead heater. But from Mouser or Digikey, the ATMega is about $3, the MSOFETs about $3, the 4 A3977s $32 total board price about 1/2 of yours. The ATMega is going to be working its heart out generating 2 phases for each of 4 stepper motors, each running at a different speed, but that is why I am using an Atmel instead of the Pic, PICAXE, or BASIC Stamp. Once the design is done and the software coded, others should be able to plug-and-play after only changing a few constants like X axis travel per tick.


With $200 or less for mechanical, motors for $50 for 4, and electronics for about $50, we have a 0 to 3D respstrap for only $300!


Mike







mccoyn Wrote:
-------------------------------------------------------
> > To reduce cost for first time 3D printer fans, I
> am also looking at making a single controller
> board for the whole machine
>
> This sounds a lot like a project I have been
> working on. It will by a 4" x 3" PCB with all
> through hole mounted hardware. The main
> components will be 4 Pololu stepper drivers, an
> Arduino Mini and a couple MOSFETs. Here is my
> cost breakdown:
>
> stepper drivers: 4 x $13
> [www.pololu.com]
> microcontroller: $19
> [www.nkcelectronics.com]
> --5328516.html
> PCB: $40 [batchpcb.com]
> connectors, passive components and MOSFETs: $40
> (this is just a guess)
>
> That comes to $150 to make the prototype board.

Edited 1 time(s). Last edit at 03/09/2010 02:22PM by rocket_scientist.

I created a separate thread to discuss my electronics.

My goal is to have a clean and easy to build board. I expect that since I am going my own way, I will end up spending a little extra.

Where do you plan to get the PCB from? Or is it just going to be much smaller? If it is smaller, how are you going to accomplish that? I know the breakout boards I am using waste a lot of space, but I still need a lot of space for connectors.

---

---

Darwin clone, Gen 2 electronics, Arduino Duemilanove w/ AtMega328, 5D Firmware, Pinchwheel extruder
[www.codeerrors.com]

I'm seconding nophead on that estimation, I just looked around after seeing Adrian's blog with the drivers and wondered what was in them. I found them on Digikey for example. Also the reuse issue is big for me. I dont want to build too much I have to throw away to make a mendel. I am using the parts I bought in the lengths they will need to be and using them to make my repstrap. Linear slides with the straight rod and some nylon bushings and some white lithium grease. I figure if I can get it to print some parts, it will have lasted long enough if I don't ruin anything. I'm excited that I have an x and y stage that I hope will work for now. The extruder will be my next job to tackle. It has always intimidated me because it has turning things but I'll get it eventually.

Anton, I've moved [[English]] to [[WolfStrap-English]]. It's a slightly less confusing name for the English-language version of WolfStrap. It may be best to delete the [[English]] once [[WolfStrap-English]] is up to date (text merged, etc).

These are the two pages we want.
[objects.reprap.org]
[objects.reprap.org]

This one needs to be deleted once
[objects.reprap.org]

is happy that [[WolfStrap-English]] is up to date.

---

-Sebastien, RepRap.org library gnome.

---

Remember, you're all RepRap developers (once you've joined the super-secret developer mailing list), and the wiki, RepRap.org, [reprap.org] is for everyone and everything!

@ Sebastien

can you please delete the wrong page... i dont know how.

I think Anton makes a good work.

---

Mfg
Wolfgang

Aller Anfang war schwer - Wolfstrap

Reprap-fab.org

Erfahrungen kann man leider schlecht weiter geben, die muss man selber machen.

@ bjbsquared: I've been worrying with the z axis for the cable-auger....




This is probably too big. The Lowe's here in town didn't have any 1/2" mdf so I think I'll be using the 5.2mm plywood I have. Cut it up in 2's and glue them together to make ~1/2" thickness.

I've attached the sketchup7 file.

The z only has 4" of travel. 7" on x and y.

The cable drive will take a few more days to actually get working. Rolling it with my fingers gives huge force. Just using some 20awg hookup wire on a bolt but it makes me thing it'll work.

Put a WolfStrap extruder on it and we're off printing!

Looks like you are iterating towards my HydraRaptor layout: [hydraraptor.blogspot.com]

I made the side panels deeper to give it more strength and I mounted the z-axis on a panel rather than suspending it on rods like you have done. That panel braces the top and sides to make them rigid. I also put a back on for more rigidity for milling.

All the wooden pieces were simple rectangles so I got them all cut at B&Q from two panels. You get two cuts free and the rest for 50p each, but they didn't charge me. So for the price of two sheets I effectively got a kit of parts to make the entire frame.

I am thinking of making another machine like HydraRaptor but with an XY table similar to the above. I will just use Reprapped parts to mount the motors, tubes and bearings. I think that will make a machine just as capable as Mendel but much cheaper, less RP parts and easier to assemble (Mendel is very time consuming to build IMHO).

To get the same build area as Mendel it only needs to be a little bit wider, and somewhat taller. Being moving table it doesn't matter how heavy the head is so I can have multiple extruders, either side by side, or on a turret style carousel. No need for complex head changing mechanisms or Bowden cables.

Making the frame from sheets rather than rods is cheaper and easier I think. If you count number of parts I would think it would have a higher self replication factor than Mendel.

---

[www.hydraraptor.blogspot.com]

That's the first time I ever saw hydraraptor. I thought yours was a cnc mill that you had converted. Guess we should all take a closer look at your earlier work.

Here's the first attempt at a cable drive. Maybe more tomorrow. Gotta go to work soon.


edited to include the picture!

Edited 2 time(s). Last edit at 03/12/2010 11:29AM by Arvin.

Hrm. If I could think of a reliable and readily available rubber wheel, I'd suggest using a pinch roller system for a Repstrap linear transmission. Basically just a "lip" of plastic on or under an axis and a stepper with a rubber wheel and pinch roller on the opposite side. It would only need to be reliable enough for a few prints, as then it would be easy to convert to Forest's herringbone rack and pinion for longevity and accuracy.

D.

Darkith, I was hoping for more. Can you draw a sketch? Even just a napkin drawing scanned in would be great.

nophead: Looked at your earlier work. March 2007. Your xyz mechanics cost $550 plus wood, electronics. Came out as an excellent cnc/repstrap but at price. I'm looking for something a bit less expensive.

Edited 1 time(s). Last edit at 03/13/2010 08:45AM by Arvin.

If you've two pulleys and a belt, you could use the back of the belt as the tyre. Both pulleys pinching the table would be even better.



Edited 2 time(s). Last edit at 03/13/2010 08:13PM by murd.

The cable I bought was way to stiff to bend around the 1/2" dowel I'm using. So I used some 20awg makeup wire. Seems to work. I think I'll try some fishing line next. Probably not for a week or so. That's a nema 14 stepper.

A movie for your viewing pleasure.
[www.youtube.com]

Edited 1 time(s). Last edit at 03/14/2010 10:31PM by Arvin.