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New person here! (and a few questions)

Posted by Caliber Mengsk 
New person here! (and a few questions)
September 16, 2010 04:19AM
Ok, so I'm new here. (... and this is going to be a very long post) I've been watching reprap for a while (I think a few years) and have just now decided to post some questions. I've recently been getting into electronics. I'm working with arduino a lot now (planning on making lighting kits for models that can have a bunch of blinking lights and fading in and out lights, etc) and I know that the arduino platform has been used before for rep raps, so I'm looking at possibly building a reprap, with improvements that would lower the cost of at least the electronics.

Thing is though, I'm really quite new to all things electronics and I basically just know how to light led's and switch some relays. (I've also messed a little with accelerometers {was doing a VR kind of project, actually worked except for looking left and right... I didn't get a gyro for that XD} and wiimote input, but just messed with those a little) I've not messed with stepper motors at all, and I have very little clue of how the whole system works with reprap, but I know that I would be willing to do things like print parts and such for others.

Lastly, I've still got no clue why it's so darn(that is an r and n) expensive. I've been looking and looking, and the only 100% complete kit I could find was $800. Me being currently jobless (have around $500 saved up at the moment though) and I can't afford any kits like this. I'm fine with putting in the hours, as long as it's cheap. I'm just wondering is there any way to make it cheaper for people like myself.

I have basic experience with electronics, and a lot of time on my hands at the moment. If I can actually get the parts cheap, (assuming these motors would work: [www.allelectronics.com]:{i:0;s:40:%2203823345592a403b2f4a37a59384e7ab28f02be1%22;i:1;s:0:%22%22;} ) and use the circuits right, (http://www.azega.com/controlling-a-stepper-motor-with-an-arduino-part-2/ ) then I could probably get all of the electronics for ~$50 excluding the extruder. I also figure around $50-100 in materials for the rods, and everything else, so could it be possible (if I put the time into it by manufacturing parts from wood and such) to build a working rep-rap for under $200? Mainly, I need to know how much a standard extruder system costs. (the whole thing.)

Using the above mentioned products and links, I should be able to create an arduino and 3 stepper motor circuit on a breadboard for around $20-30 I would think. ($10 for arduino parts {a little less actually}, $10 or so for stepper parts, $10 or so for edge detection buttons, wire, etc)

Anyway, sorry for the extremely long post. I'd just like to know if it's possible I could build something like this for a "dirt cheap" price. (Dirt cheap meaning much cheaper then pre-compiled kits.)

Thanks for your time on reading this, as well as any insight you may be able to give.
Re: New person here! (and a few questions)
September 16, 2010 04:46AM
If you want to make a lot of stuff yourself, a repstrap is a lot cheaper than a reprap. There is less documentation on them, as everyone just uses the parts they find in their local shop. You can find different designs on [www.reprap.org] .

I don't really know what the cheapest one is, but most of them are cheaper than a normal reprap. The wolfstrap looks cheap to me, but not everything is translated from the German to the English article.



my blog: [reprap.tman.be]
Re: New person here! (and a few questions)
September 16, 2010 05:04AM
The currently cheapest and most advanced electronics is the Pololu version: € 9,- for the atmega, 4x € 12,- for the stepper drivers and perhaps € 10,- for connectors and passive stuff. Yes, you need four stepper drivers, as the extruder needs one as well.

Regarding mechanics, something like a Wolfstrap is pretty affordable. Less than € 100,- for all the mechanics.

Then you need stepper motors, which are between € 10,- and € 15,- per piece.

Last not least there's the extruder - unless you want to hook up a Dremel onto your robot of choice. For extruders I currently see no "golden" solution, but completed ones sell between € 120,- and € 150,-, so a do-it-yourself'd one can't be more expensive.

Oh, and build material can be as expensive as € 100,- per reel. But that's the last step.


Hope that helps.


Generation 7 Electronics Teacup Firmware RepRap DIY
     
Re: New person here! (and a few questions)
September 16, 2010 06:09AM
Well, I can get a complete arduino shipped for $15usd, and if I can use these stepper motors [www.allelectronics.com] it would cost me $20usd for four of them shipped. That would just leave the endstop sensors (extremely cheap version just being a tactile push button for each axis XD) The other components to build a circuit from the tutorial on using stepper motors with the arduino will cost around $15 for all of the components shipped. So, all total, thats $50 for the electronics and motors, which lowers the amount considerably over what Traumflug's estimated costs would be (being that just the stepper motor controllers are around $14usd as the cheapest I could find them, not counting shipping).

The only things I can't figure out pricing wise is the extruder and frame materials, extruder being the main one. At the least, I can build my own base for it out of wood and metal from the local hardware store for cheap. May look poor, but it would get the job done. As far as a completed extruder, Around $200-250USD doesn't sound reasonable at all for what it's doing. It'd almost be worth making my own extruding system if it'd be that much. I know that it's probably my nieve mind, but I don't think it would be all that hard after I figure out the fundamentals of inductive heating. I understand the basic principles of the extruder, and I don't have any clue why it would be near that much by what I've seen.

Anyway, thanks for all of the suggestions so far. From what I've gathered, the reduced price by making my own stepper controller as well as the cheaper stepper motors (if they would work. I have no clue if the accuracy, or strength of the ones linked above would be enough) make it seem viable to create a reprap/repstrap for less then $200. XD I just hope I'm right on that matter. Anyway, that's enough for now. (5:09am here, and I haven't slept yet) So, goodnight all.
Re: New person here! (and a few questions)
September 16, 2010 08:36AM
I was on your same path, and finally decided to buy a set of extruded parts. I got a Mendel, but I suppose I could have looked for and gotten a Huxley if I was more persistent.

I've not fully groked the Arduino vs. Sanguino vs. Arduino MEGA thing yet, but the primary difference, (reprap wise), is program space and (especially) i/o pins. I haven't figured out if you can have 6 endstops, 3 axis, and both a thermostatically controlled heated bed and a extruder with an arduino clone. But even if you get all that (or can get by with say only 3 endstops), will you need to buy a MEGA in three months because you want to add the latest do-dad? I'm leaning toward a "Seeeduino Mega" (clone of the Arduino MEGA), once I verify that it will work.

Endstops will likely be three hand built optical and three "cherry" brand switches. I'm not sure that the switches themselves will provide enough repeatable accuracy, but I'm told that most of the makerbots run with no sensers at all. (I've seen a video where someone nudges their makerbot to the middle of the platform before starting).

Pololu stepper boards seem to be the best deal. I could buy the bare boards and make them myself, but my labor is worth something and I believe I would not save anything on parts.

I was going to hand-cut the "squashed frog" (there's an easy to cut pattern out there as a A4 pdf file), but I sniped a laser-cut thick sheet set off ebay for <$20. Again, my time has value and getting the A4 file printed or converted to letter size, pasting it on to the MDF and cutting it out would have taken at least 3 hours.

I've saved a tiny amount by avoiding nyloc fasteners, but you can easily blow any saving on one bottle of thread-lock. I just hate nyloc.

The steppers you linked to are too small and weak, I'd wager. I was looking at them myself.

-
I think there's probably a lot of room for improvement for parts for North American makers. Remember, they're designed specifically to be extruded from a 3-d printer that does not yet print support material. Remember, they're designing to try to increase the amount of extruded/printed parts. While its a worthy goal to try to simplify replication so that someone in the third world can replicate a copy with nothing more than some copper filings, some wood, and some plastic made from yak milk, my goal is to get to the point where I can print parts.

When I reach that goal, I plan to redesign some of the parts to ease the creation of a 3-D printer. For example, this could easily be made from plywood or laser-cut MDF, and it would be a drop-in (and cost effective) replacement for six extruded plastic pieces and six cut pieces of studding and a number of nuts and washers. You just could not print it. That's the wrong way of progress for the core Reprap group, but I'd say if it gets more people printing plastic parts, that's more people getting roped into the project.

There's nothing wrong with Wolf-strap et al., but I'd bet that if had a buck for every incomplete rep-strap, I'd be able to afford a makebot that was hand assembled by Bree himself. Instead, I've decided to throw money at the problem, build a standard Mendel myself, get to the point where I can print parts, and improve my Qcad skills for my next move.


Caliber Mengsk Wrote:
-------------------------------------------------------
> Well, I can get a complete arduino shipped for
> $15usd, and if I can use these stepper motors
> [www.allelectronics.com];
> id=SMT-108&extra=a:2 it would cost me $20usd for
> four of them shipped. That would just leave the
> endstop sensors (extremely cheap version just
> being a tactile push button for each axis XD) The
> other components to build a circuit from the
> tutorial on using stepper motors with the arduino
> will cost around $15 for all of the components
> shipped. So, all total, thats $50 for the
> electronics and motors, which lowers the amount
> considerably over what Traumflug's estimated costs
> would be (being that just the stepper motor
> controllers are around $14usd as the cheapest I
> could find them, not counting shipping).
>
> The only things I can't figure out pricing wise is
> the extruder and frame materials, extruder being
> the main one. At the least, I can build my own
> base for it out of wood and metal from the local
> hardware store for cheap. May look poor, but it
> would get the job done. As far as a completed
> extruder, Around $200-250USD doesn't sound
> reasonable at all for what it's doing. It'd almost
> be worth making my own extruding system if it'd be
> that much. I know that it's probably my nieve
> mind, but I don't think it would be all that hard
> after I figure out the fundamentals of inductive
> heating. I understand the basic principles of the
> extruder, and I don't have any clue why it would
> be near that much by what I've seen.
>
> Anyway, thanks for all of the suggestions so far.
> From what I've gathered, the reduced price by
> making my own stepper controller as well as the
> cheaper stepper motors (if they would work. I have
> no clue if the accuracy, or strength of the ones
> linked above would be enough) make it seem viable
> to create a reprap/repstrap for less then $200. XD
> I just hope I'm right on that matter. Anyway,
> that's enough for now. (5:09am here, and I haven't
> slept yet) So, goodnight all.
Re: New person here! (and a few questions)
September 16, 2010 09:12AM
Caliber Mengsk Wrote:
Quote
Caliber Mengsk
these stepper motors

The ones you linked there have a 3.6 deg step angle, which is to much for the belt driven axes. All RepRap machines so far are designed with 1.8 deg steppers in mind and 0.9 deg steppers for the belts would be a plus. Also, you want enough torque.


Generation 7 Electronics Teacup Firmware RepRap DIY
     
Re: New person here! (and a few questions)
September 16, 2010 02:36PM
@Pica: Unfortunately, I don't have the money to live with the philosophy of "throw money at it". Anyway, using the tutorial link in my last posts, you can actually set up a unipolar stepper motor with just two wires, making for 8 wires for all four stepper motors, Things like the temperature sensors go to analog inputs, and if the end stops are just tactile buttons, they can be on either the analog or digital pins. So, even with the tactile buttons as end stops on there, you'd only be at 8 outputs and 6 inputs. Doesn't leave a ton of room, but leaves open 4 pins in either analog inputs or digital inputs. Not much room to work with, but like I said, my lack of money is the biggest thing.

@Tramflug: Ok, how powerful does the stepper motor need to be? Would something like 700g/cm work? Or does it have to be something much stronger like the sparkfun one that's 2.2kg/cm? ( tongue sticking out smiley And this is why I ask this kind of stuff before buying anything. ) If something as little as 700g/cm would work, Jameco has a few cheaper ones (less then $10 each) like this one [www.jameco.com] that may be able to work. It doesn't have to be fast, as long as it's something I can print parts with it.

@All: Thanks again for all the help you've been.
Re: New person here! (and a few questions)
September 16, 2010 03:08PM
Re: New person here! (and a few questions)
September 16, 2010 03:11PM
Caliber Mengsk Wrote:
-------------------------------------------------------
> @Pica: Unfortunately, I don't have the money to
> live with the philosophy of "throw money at it".

I totally understand, but I figured I'd be better off mowing laws or something in my spare time rather than figuring out how to save a few bucks. I bought some un-rated steppers back when I thought I was going the repstrap route because I could toss them on another order. I'm hoping I did not blow that cash.

I also figured that I would sell at least one set of parts ASAP, which would (not counting the value of my time), make up for the extra cash that was "thrown" at the problem. That and I'll be printing sooner. Much sooner.

> @Tramflug: Ok, how powerful does the stepper motor
> need to be? Would something like 700g/cm work?

You want at least 19.4 oz-in for your steppers for a mendel style repstrap. Details are here: [objects.reprap.org] Since you are forging your own path, there may be cheap NEMA frame 23 or larger that you could adapt. Make sure you have at least decided on your drivers before shopping for steppers.

I'd check the wolf-strap wiki page for details if you go that route.



> Anyway, using the tutorial link in my last posts,
> you can actually set up a unipolar stepper motor
> with just two wires, making for 8 wires for all
> four stepper motors, Things like the temperature
> sensors go to analog inputs, and if the end stops
> are just tactile buttons, they can be on either
> the analog or digital pins. So, even with the
> tactile buttons as end stops on there, you'd only
> be at 8 outputs and 6 inputs. Doesn't leave a ton
> of room, but leaves open 4 pins in either analog
> inputs or digital inputs. Not much room to work
> with, but like I said, my lack of money is the
> biggest thing.

Thanks, that helps me some. I'll probably us that to pose a question on the forums in a bit.
Re: New person here! (and a few questions)
September 16, 2010 09:08PM
Caliber Mengsk Wrote:
-------------------------------------------------------
> Anyway, using the tutorial link in my last posts,
> you can actually set up a unipolar stepper motor
> with just two wires, making for 8 wires for all
> four stepper motors, Things like the temperature
> sensors go to analog inputs, and if the end stops
> are just tactile buttons, they can be on either
> the analog or digital pins. So, even with the
> tactile buttons as end stops on there, you'd only
> be at 8 outputs and 6 inputs. Doesn't leave a ton
> of room, but leaves open 4 pins in either analog
> inputs or digital inputs.

OK, here's how I figure it:

8 pins for 4 steppers; 6 pins for 6 endstops; 2 pins for turning heaters on and off (one bed, one extruder) and 2 PWM pins for the two thermometers.

That's a total of 18, which exceeds the available pins for the RBBB kit. That's the cheapest kit I've seen unless I buy a bare board or breadboard , and self source the parts.

Maybe I need to ask in the electronics forum, but does that all seems correct? And exactly what are the shortcomings of not having all six endstops? Is running only 3 on a mendel doable? What shortcomings go along with that?


--
My blog's Reprap feed: [blog.markbova.com]
I'm currently working on a stock Mendel build with a Seeeduino Mega and four Pololu A4983 stepper controllers.
Re: New person here! (and a few questions)
September 16, 2010 09:19PM
Thanks for the information and suggestions. I've been looking on ebay and found a pretty good deal. 8 motors with 200 steps (1.8degree step) and at least 25 oz/in (the link you guys gave says a minimum of 19.7, so this should be great.) and possibly up to 35 oz/in, though I'll stick to the minimum number for expectations. Best part, is it's cheap per part. $34 USD for all 8 including shipping. That's $4.25 each. Only problem is that since they are bi-polar, I'd probably have to buy and h-bridge and make my own circuit, or buy four motor controllers.

Unfortunately, 4 motor controllers aren't cheap being pre-built. Cheapest (and most readily available) seems to be the pololu stepper motor, and they are $13 each. [www.pololu.com]

T_T If only it were all cheaper. Other then that, I'd need and extruder, and then other materials to press it all together into a workable machine. Gah... so much on this project.

At least it is a good deal on the stepper motors all in all.

O-o...... Ok... XD I just realized something... I have no clue what software is needed to actually be able to print a 3d object. O-o Do I just need something like 3d studio max with a plugin? (I have it from a student discount ^_^) Or is it some kind of proprietary software specifically for this kind of stuff?
Re: New person here! (and a few questions)
September 16, 2010 09:27PM
pica Wrote:
-------------------------------------------------------
> Caliber Mengsk Wrote:
> --------------------------------------------------
> -----
> > Anyway, using the tutorial link in my last
> posts,
> > you can actually set up a unipolar stepper
> motor
> > with just two wires, making for 8 wires for all
> > four stepper motors, Things like the
> temperature
> > sensors go to analog inputs, and if the end
> stops
> > are just tactile buttons, they can be on either
> > the analog or digital pins. So, even with the
> > tactile buttons as end stops on there, you'd
> only
> > be at 8 outputs and 6 inputs. Doesn't leave a
> ton
> > of room, but leaves open 4 pins in either
> analog
> > inputs or digital inputs.
>
> OK, here's how I figure it:
>
> 8 pins for 4 steppers; 6 pins for 6 endstops; 2
> pins for turning heaters on and off (one bed, one
> extruder) and 2 PWM pins for the two thermometers.
>
>
> That's a total of 18, which exceeds the available
> pins for the RBBB kit. That's the cheapest kit
> I've seen unless I buy a bare board or breadboard
> , and self source the parts.
>
> Maybe I need to ask in the electronics forum, but
> does that all seems correct? And exactly what are
> the shortcomings of not having all six endstops?
> Is running only 3 on a mendel doable? What
> shortcomings go along with that?


With the arduino, you can simply use the analog inputs as digital inputs, You just do an analog read and check if the value is above half of the max value. If it is, then it's high (on) otherwise it's low (off). So, in that case you can have 14 on/off outputs (digital pins 0-13) as well as 6 analog inputs (analog 0-5). I'm also wondering how much you found the cheapest one for? I've been on the arduino forums quite a bit before, as well (with mention towards the light kit project of mine) I've just searched for the cheapest arduino. I found a site that has them for $10 +shipping, which is $5 flat rate to the US. The shipping price doesn't go up the more you buy, so you can get them real cheap even after shipping if you buy in bulk. That doesn't include the FTDI cable either though, but no RBBB kits do really. [themakerspace.com] if you wanted to check it out.

Also, from what I've read, the end stops aren't required unless your steppers slip a lot. From what I can tell, it just lowers accuracy a bit. Of course, XD I have no clue for sure, but that's just what I've seen.
Re: New person here! (and a few questions)
September 16, 2010 10:23PM
I'm new here too, but all this stuff is covered in the wiki already. You will probably spend too much money and time going down wrong paths unless you spend at least a week reading the wiki.
VDX
Re: New person here! (and a few questions)
September 17, 2010 03:16AM
... most people use only 3 pins for the 6 endstops - every axis has two endstops routed parallel to one pin ... others use only one pin for all axes, as they home every axe separate ... and if one of the endstops is triggered during build, they simply stop and throw an error or check by backstepping every axis some steps, which endstop ist was ...

This would reduce the needed pins ...


Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]
Re: New person here! (and a few questions)
September 17, 2010 04:22AM
I'm reading the wiki too, but it's not all there. And what is in there isn't organized perfectly. And some of it is outdated. For instance, It would be great to be able to have a page that compared ATmega1280, atmega644, and ATmega328 based mainboards in a table-like format. That's essentially what I'm trying to wrap my head around right now.

Right now I'm leaning toward the ~$50 Seeeduino Mega; Pololu A4983 $13 x4; and a breadboarded "shield", endstops, and temp sensor boards. That's at least 3 suppliers, but I'm guessing I'll combine that with another project and end up with orders to Digikey and Mouser for the discrete stuff.

That's maybe ~$150 for somewhat future-proof electronics, as long as I can remember what end of the soldering iron to hold.

All of that planning could be blown away if the all-in-one Gen-6 board or kit was buy-able today.


Buback Wrote:
-------------------------------------------------------
> I'm new here too, but all this stuff is covered in
> the wiki already. You will probably spend too much
> money and time going down wrong paths unless you
> spend at least a week reading the wiki.
Re: New person here! (and a few questions)
September 17, 2010 06:09AM
Caliber Mengsk Wrote:
> O-o...... Ok... XD I just realized something... I
> have no clue what software is needed to actually
> be able to print a 3d object. O-o Do I just need
> something like 3d studio max with a plugin? (I
> have it from a student discount ^_^) Or is it some
> kind of proprietary software specifically for this
> kind of stuff?

For the modeling itself you need a 3D package which can output STL files. There are many open sources and free ones available, my personal favorites being Wings3D and OpenSCAD. More alternatives here: http://objects.reprap.org/wiki/Useful_Software_Packages

There are also several alternative software solutions to slice the model, generate gcode and communicate with the printer. I like RepSnapper, but many people use the RepRap host and Skeinforge. Take a look here: http://reprap.org/wiki/RepRap_CAM_Toolchains

Edited 1 time(s). Last edit at 09/17/2010 09:08AM by Nudel.
Re: New person here! (and a few questions)
September 17, 2010 09:49PM
I've finally ordered an electronics package:

robotshop.com
Seeedstudio Seeeduino Mega Microcontroller
Arduino Prototyping Shield PCB for Arduino MEGA
4x Pololu 8V - 35V, 2A Single Bipolar Stepper Motor Driver

total with shipping was USD $114.11

I'll still need to buy some parts for the end stops, and to control the heaters (as well as the thermistors, and the heaters themselves), but hopefully that won't be over $50.

I could have shaved maybe $40 off the total if I'd gone with the a RBBB type controller. I wish I could contribute something to Triffid_Hunter's FiveD project, but everything there is over my head. I'll be looking here for my next machine.

I could not figure out how to make a stepper controller for less than $13.

I would have wanted a RAMPS kit from ultimachine.com but they were out of stock.
Re: New person here! (and a few questions)
September 18, 2010 07:25AM
I have been working on a micro version of mendel and trying to simplify the design in the process. See the thread under RepRappers [forums.reprap.org] There is also kelso? who is documenting building a Mendel - he has done a great job and he posts more than once a day sometimes. You must read his thread.

I have bought the threaded rod and the bearings, nuts and bolts. I will try nail polish for locktite as I have found this works great on other things in the past. The steppers will cost me $20 ea (require 4) in Australia plus shipping. I have been busy with other things the last couple of weeks. Today we were moving house after 22 years. Guess what - we threw out some old roller blades - I am going to rescue the bearings in case I build another reprap. So, look at the old trash for old roller blades for the bearings! I am not using endstops initially, but will probably use microswitches later. Both ends may as well be in parallel as the software will know which end it reached. In reality it should never hit an endstop unless it is skipping steps. In fact, all endstops could be in parallel because if you start at a known point you should never hit one. If you do you must stop as an error has occurred.

Try some old printers for parts such as rods and endstops. Not sure if the belts will be any use. I have 2 identical printers for dismantling to see what I can recover.

To keep the cost down, you could use this method and replace the plastic joints with wood and drill them.

The extruder is going to cost you a bit because this is where I see lots of people have had problems. I have a few ideas, but ideas cost money to try. I will use a stepper here - makes all four motors identical with identical drivers.

I will do my own electronics and when they are running will probably make the boards available. The electronics could be done much cheaper as you state, but remember, if you are buying from a shop they have to cover a lot of overheads and stock.

Edited 1 time(s). Last edit at 09/18/2010 07:28AM by cluso99.
Re: New person here! (and a few questions)
September 18, 2010 06:57PM
Disclaimer : my 3d printer is currently in the design and construction stage. That being said, I have build a rather robust 4 axis milling machine with stepper drives, as well as a host of other projects in my day. I don't want to come off as negative but going at it in the absolute minimum figures with everything is not the path to success. What happens when you accidentally toast one of your $13 stepper drives? The whole machine doesn't work because of that one little thing.
Projects like this never cost the minimum amount, I find a good estimate is to figure your cost as complete as you can and then double it.
You also don't say what kind of tools you have access to or knowledge of use. I personally have access to a cnc lathe (and the know how to program it) so an extruder nozzle costs me nothing but a little time, but without anything you'd need a drill and bits at a minimum, and those aren't free.
Again, not trying to rain on your parade, but trying to illustrate that costs rise when you don't consider all the factors. The good news for you is that if you have nothing but time you can spend it reading everything you can, both the wiki and blogs. So much info. And every bit of it will help you to reduce your cost. If you must do it on nothing, plan out as much as you can, and add at least something for a fudge factor.
Re: New person here! (and a few questions)
September 18, 2010 09:01PM
>What happens when you accidentally toast one of your $13 stepper drives?

You buy another one. Except these stepper drivers aren't drop-shipped from DealExtreme in China. They come highly recommended. They seem to work very well.

I didn't totally price out the 2.3 stepper controller as a self-sourced kit, but fully assembled they go for like $23-35 each. Yet everyone on the forums says the Pololu A4983 are working great, are developing future hardware around them, etc... I'm not going cheap by going Pololu.

That being said, you can call me cheap for going Seeeduino Mega rather than Arduino Mega but at least I didn't go breadboard a ATmega328 because I'm too cheap to blow $17.50 for an Boarduino ;-)
Re: New person here! (and a few questions)
September 18, 2010 09:18PM
With 5lbs of filament on the way, I'm up to $650.10 total. Most people would not count the inital consumbables, but what can I do without it? Expensive hobby.

I still need the extruder heater, the optional heated bed resisters, two thermistors, and the end-stops.

I'm thinking to breadboard the endstops. There so simple, and only a handful of dirt cheap parts. Even buying a premade board would take longer and add another parts supplier to the mix. (7 vendors so far, except that 5 have delivered already).

It seems I went deluxe a few places, cheap where I think it would not matter (they say you can get cheap bearing and non-stainless rods), and I'll be comfortably below $700.

I'll have the heated bed, the larger build area, and still be under the basic entry level price for a makerbot.
Re: New person here! (and a few questions)
September 18, 2010 10:38PM
The point was not the cost or what to do when the inevitable happens, take any component down to a $0.03 washer. If all you plan for is the bare minimum, as the original poster seems to be doing, prepare for problems in the end.
Everyone has a cost/time whatever threshold, I'm not criticizing people for being "cheap". It's just that starting a project with a lower than average budget an zero room for things to fail is in my opinion not the best way to go.
Re: New person here! (and a few questions)
September 19, 2010 02:16PM
I'm expecting some problems, but I'm also expecting most of them to be cheaper ones. It's not likely that all of the electronics would go bad, nor is it likely that every piece of metal will be slightly bent or anything of that sort. To expect everything to be broken at one point during the process is be a little over cautious.

As far as the expense of the extruder system, after I have the stepper motors here, I can try a few things to make my own extruder system. For instance, my first basic idea for an extruder is to create a semi-low wattage induction heating system with a basic system for feeding the material by having a notch cut out for a screw to be placed, which is driven by the stepper. The material doesn't have to not have notches, and should be a fairly easy and accurate way to move the material. That said, I don't really expect it to work first try, but I do expect that I can buy semi-cheap materials to make a system that can push the material into the heating head.

O-o I don't think I know everything, nor that I think something won't go wrong, but I do know that not everything will go wrong. Being on a limited budget sucks, and I agree that you shouldn't spend as little as you can on everything, but there is a risk reward system, and in my case (being into electronics) buying stuff like stepper motors and controllers aren't a risk even if I do botch the project and run out of money for it. But, if it does work, I can document the process, and make it easier on myself if I make another, as well as post it for all to see and make it cheaper and easier to understand, and even possibly make some, if not all, off the money I invest in it back.

You are right to expect bad stuff will happen, and on cheaper things like washers, nuts, bolts, rods, etc it's usefull to buy extra, if anything you can sell it here when finished. That said though, if you don't have the money, you don't have the money. (XD Then again, that said, if you don't have the money, you shouldn't do it in the first place.)

.... I hope I didn't repeat myself too much...........

Anyway,I do think I will try to make one, but it would effectively be a repstrap. I would like, over time, to make something that doesn't require anything but printed parts, electronics(including motors.), and heating head. Anyway, I'll probably compile a purchase list and add it all up. If I can get it all in around the $200-250 range, I will be extremely happy. At this point I know that all of the electronics and motors will be around $100 (arduino, 4 stepper motors, 4 stepper controllers, endstops, but not the heater head.) I still have a little more research into an induction heater before I would buy that stuff though, in fact, I know I have material lying around to make the copper coil, and all I need to figure out is the circuit to make an induction heater, which I think I may have found the simple diagram I've been looking for here: [webpages.charter.net]
Re: New person here! (and a few questions)
September 19, 2010 11:15PM
Caliber: I am sure you could experiment with the extruder fairly cheaply until something worked reasonably. Perhaps some parts from an old printer like the plastic cogs to feed the filament. The brass tubes and nozzles are available on here and reasonably priced and you can buy the heater wire too. Perhaps some PTFE tube too. The rest is really playing. I saw someone used a piece of dowel drilled. It may not be as good, but then again it is experimenting and maybe you may make a great find that we all can use and reduce the overall cost.

I have found the rods for a micro-mendel to be quite reasonably priced. I have found skate bearings from old roller blades (after I bought them sad smiley ). I believe I have reduced the complexity and that I can hopefully make the plastic parts in wood initially. Once working I can make the plastics. My version (providing it works) will use a LOT less plastic and parts.
Re: New person here! (and a few questions)
September 19, 2010 11:31PM
Well, I already have some copper to try to make an induction coil, I just need the components. I may go out and about up to lowes tomorrow to see what could be useful for that. Now that I think about it, my Dad has a drill press I can use to bore out my own holes in stuff. Not quite a lathe or anything, but I think I should be able to find a 3mm steel rod or pipe to be the induction core, and then shape it into the right size for extruding the material out. The absolute only thing I'm not sure about is if I can actually figure out a simple induction heater circuit. The link in my last post gives me hope that I can do it, and even at the 24v that the stepper motors I would be getting would run at. No stepping up the voltage needed.

I've also found that MDF is only ~25 for a 4x8x.5in sheet of it, so I think I could easily make the plastic parts out of wood like you were suggesting. If all of that is true, including the electronics, I'm looking at right around $150-200 in parts. XD As long as I can make the extruder/heater on my own. Anyone know of a different heating method that I might be able to use that's quite cheap? At this point, I can safely say that the basic low power induction heating system should be less then $10. XD But what do I really know. I'll look at it some more and probably go out tomorrow. As far as the extruder, I have some ideas on that already.

That's all for tonight. If I do end up making the induction heater work right, I'll post up a topic on it, and then be on my way to making a reprap/repstrap.
Re: New person here! (and a few questions)
July 20, 2011 04:08AM
Sorry, posted in wrong thread!

Edited 1 time(s). Last edit at 07/20/2011 04:09AM by droftarts.
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