Has anyone built a Prusa I3 ?

Where did you buy the metal parts and how much did it end up costing ?
Did you print the plastic parts or buy them ?
Are you happy with it ?
How is the Z-axis resolution ? (I have worries about threaded rods...)

Anyone willing to help me out and print the parts needed for the wood box version,
I would be super grateful (I'm in Ontario).

Thanks.

This is probably more detail than you need but here goes...

I just built a Prusa i3 (single plate) around the laser cut frame from SeeMeCNC ($53), sourcing parts from various places. I bought 5 NEMA 17 motors on eBay for $83 (too much). I bought smooth and threaded rods and all the metric hardware from McMaster-Carr for around $50 (good prices). I bought the RAMPS kit with heated bed PCB and Smart LCD from Gadgets3D for $201 with shipping (a great electronics kit). I got a set of plastic printed parts on eBay for $70 (now it sells for $50). An assembled Wade extruder (I was lazy) was $44 with shipping on eBay. A DIY Tech Shop J-Head hot-end was $55 with shipping on eBay. 3x GT2 pulleys and belts were $57 with shipping on eBay. Originally I used an ATX 12V 15A power supply (free!) but I decided to get more amps, so an LED strip PSU was $30 on Amazon. I went to the local hardware store for zip-ties, rubber hose (for z threaded rods), etc. For swappable build surfaces I just cut up a large mirror into a few 8" x 8" squares (free!).

My total gross cost was $813.71 for parts plus $82.79 for shipping ($896.50). I spent $56.21 on printer supplies like Kapton and a 1kg spool of plain PLA. I spent $114 on tools, including an angle grinder to cut rods, a caliper, an allen set, a wire stripper, a soldering iron, etc. My GRAND TOTAL including all overages and redundancies was $1074.84.

As a complete newcomer, in the process of this build I picked up lot of extras we didn't need (including two "wrong i3 dude!" plastic parts sets) most of which I'm re-selling. But I also spent a bit on tools and hardware that I know we'll need for future builds. So I don't count that $300 in the estimate for a second build. With more careful sourcing, I feel anyone could build a Prusa i3 (box frame) for around $600.

Instead of $83 for 5 motors, now they can be found for $50. Instead of $200 RAMPS electronics, there are now $100 all-in-one electronics (or solder your own). (Of course for quality it's hard to beat Kliment's 4pi). And soon I'm sure there will be complete printer kits including everything but the wood for even less, with only one shipping charge to worry about.

As for the Z axis resolution, I find it to be great with the 5mm threaded rods. I have no problems with layer height at all. Overall it's a good design and I've been getting great prints with PLA.

Edited 3 time(s). Last edit at 03/11/2013 05:10PM by Thinkyhead.

Thanks for the awesome reply, Thinkyhead !
This actually helped me a lot.
Care to upload some pictures of prints you made ?

Im in the getting the parts together I have the 6mm aluminum plate with modified tapped m4 holes as the git file holes measure 3.25mm so if any one builds and gets it cut themselves change the holes sizes im doing my modifications on the mk2 im building after the one im building now, im in uk as I know that the i3 isnt finalized so theres few different various versions but I wanted to build i3 due to its easer to get too the x carriage for my further development.

I am currently building 2 Prusa I3

Where did you buy the metal parts and how much did it end up costing ?
Orchard Supply Hardware
(4) 1.5in angle steel 12.1" long ~$14 TIG Cut with cold saw to length, then welded. The welds ground smooth, then painted black
Smooth rods ~ $14 cut with a cold saw to length.

Did you print the plastic parts or buy them ?
I have been printing the parts. I already have a Prusa I2. I have been modifiing the parts slightly to make the parts easier to produce from molds. Printer #1 is all printed parts, Printer #2 is being made with the parts cast into molds. The cast parts are using EpoxyCast 655 and heat treated. The plan is to use a heat chamber with Printer#2

Are you happy with it ?
Not complete yet, But so far everything is going smoothly.

How is the Z-axis resolution ? (I have worries about threaded rods...) Since I have a Prusa i2 with threaded rods, this doesn't concern me much. How ever I am considering using ACME threaded rods instead.

Hi HoloPed, Here's some what's been going on with my Prusa i3 so far…

After dealing with the usual technical glitches everyone encounters in these builds, this is turning out to be a decent printer. At the moment I'm having a leaky nozzle issue — hole in the inner PTFE liner — so I have to print slowly. Next week I'll have a new nozzle and I can start tuning the printer for more speed. In other news, a couple of weeks ago the RAMPS D2 diode burned up so I had to replace that. Then the x-motor-end plastic piece developed a crack. Then the y belt needed some superglue. Then the extruder motor pulley came loose from vibration, so it's good to keep tightening things. Then the (NEMA17) extruder motor was overheating on long prints, but I found I could tune the voltage down pretty low and still have plenty of torque without all the heat. Sadly I have to use this (24V) motor in unipolar mode (6A) because the bipolar resistance (12A) is too high.

In-between problems I've been calibrating the extrusion and other settings and printing lots of objects. I got the hang of OpenSCAD pretty quickly and have been using it to design custom parts to mount a Wade extruder on the i3 x-carriage, a box to contain the RAMPS electronics, and right now I'm printing the top half of a housing I designed for the SmartLCD.

I've printed a number of Things. Some of them are even useful.

So far I've been printing PLA almost exclusively, trying to master this stuff, sometimes on bare glass but mostly on blue tape. I've used Slic3r 0.9.8 for all my slicing so far. I wanted to get the default working before diving into SFACT / Skeinforge / KISSlicer / etc. It took a while to figure out how to tune extrusion, but I have it down to a science at this point. It also took a while to get first layers right (just a little squished) but I think I have that down now.

My goal next week is to finally get the printer into shape where I can leave it unattended for 8 hours without any worries. A reliable nozzle really is the last piece of the puzzle at this point; I've tuned everything else really well. After that, once I finish printing the rest of the new parts for the printer itself, it will be time to start thinking about how to use this revolutionary device for fun, creativity, and to profit mankind. Naturally I expect to keep upgrading and tweaking this printer for a long time to come, and of course I want to print several sets of printer parts and get them out to the masses.

One thing this printer has going for it is how easy it is to move around, and how easy it is to take apart for flat packing, if you need that. When I catch the printer out of the corner of my eye, it always strikes me how "steampunk" it looks, especially with the big Wade extruder on it, and that it doesn't look like it has enough parts to be able to do the things it does. It looks more like a prop from a Terry Gilliam film than a genuinely useful device. Kudos to Snr. Prusa for his minimal sense of design.

Edited 2 time(s). Last edit at 04/06/2013 01:15AM by Thinkyhead.

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Awesome information Thinkyhead!

I'm sourcing a Prusa I3 now and I just can't thank you enough for that fantastic sourcing information. I think sourcing one of these things is as tough as putting one together.

Me and some others are in the midst of building a Prusa i3 mixed with a Mendel v90. We loved both designs and they were very similar so we decided to take the best parts from each and custom design the rest. We are only in the beginning stages of a mock up design. The final version will more then likely be made from Dibond and aluminum alloys with a few carbon fiber parts. I attached a few pics of the mock up stage.

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Hi all,

I was wandering if anyone could tell me how the print quality is from an i3 with the 6mm alu frame the way Prusa designed it?
Due to the manufacturing tolerances of aluminium sheets I have found that a lot of sheets have got a bow in them.
As far as I know the tolerance is 7mm on a 1m lenght. (Information got from sheet manufacturers) So if you put a 1m ruler on top of the sheet you could have as much as a 7mm gap and it would be within manufacturing tolerances. So in worst scenario you could have as much as 2.33mm sway from bottom to top on a frame.
My question here is, as I have seen this, if a frame has got a little bit of bow in it from bottom to top how have that affected the z as you print high objects?
The i3 alu frame version looks very sleek, and it is a shame to have to brace it due to bowing and to machine the surface of the frame would be too costly. Trying to bend it does not look like an option to me.

And, have anyone made the single frame from acrylic? If so, how thick (10mm?) acrylic to give it enought rigidity and was there any problems with cracking?

I am in process of putting one together myself and must say it is probably one of the most sleek and elegant printers I have seen, of this style printers.

Regards
Jan

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[3dprinting4u.wordpress.com]

You may have seen a bow in a particular aluminium frame but theres quiet a few alu single frames out there and prob more, which haven't been wrote or blogged about. Any material can get a bow in depends on the quality of supplier and there tolerances.
I gone for the single aluminium frame myself theres richards which is on google+ the same frame as mine hes prob 90% complete on his build, theres several varients of i3 even the one reprap squad shown is a new varient to me, it all depends what you like working with.

if your looking for materials for the structure Dibond is a great one as well. Its not as expensive as aluminum but has simular regidity. Its what Nopehead uses on the memdel90.

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I built an i3 out of 6mm acrylic. Later I built another one with 6mm aluminium frame Of course the latter is stiffer, but the former works nicely too (and it has a very ethereal appearance).

to be honest it was cheaper to get the aluminium water jetted than 6mm acrylic £50 for aluminium £57 for acrylic, I was trying strum up so interest in the aluminium frame to fund my project, but the guy from spain pretty reasonable so knock me of my price, i looked into dibond but u cant thread it i've been told, but wouldn't effect nothing just put a washer and nut behind. My i3 build is taking its time mainly down to the money but atleast its about £200 left to spend and i'll have a 3d printer.

I'm just finishing my first i3. I had the frame waterjet cut. I printed the parts. I sell i2 and i3 hardware, bearings and rods. Wantai motors, T2.5 belts and pulleys. I'm using RAMPS 1.4 and a J-Head IV. I haven't decided on the extruder yet as I've been focusing on the frame and hardware. The single plate printed parts are tough to find but there are a few out there. The vitamin BOM isn't yet complete for most builds. I've got plenty of nuts, bolts and washers in most sizes, I've been pulling them from the bins as I need them. I'll post on the Wiki when I get a final count going. After seeing that E3D hot end I'm curious to try it out.

A 7mm/1m permanent bow in 6061 AL is out of the norm. With the plate frame being 370x370 even with some warpage of a larger sheet there shouldn't be an inherent issue with the material. If there is it could be poor storage or material that isn't the best quality.

Some of the parts are more difficult to source but it's getting easier. The support and build docs aren't as stable or mature as the i2 and I think many first time builders want to or are better advised to build an i2 right now and wait for the i3 to settle in a bit more.

To be honest the problems I have had so far as been minimal although its not built yet, but changing the 3mm holes on plastic parts, enabling me to tap the 3mm holes to 4mm worked.
I am going for the e3d hotend and have made tiny adjustmenst on extruder and made a groovemount plate to fit the e3d, ill post it tonight as im in work and you are right theres so many different builds.

Thank you for some valuable info
I have put one together apart from belts and hotend/extruder.
Tested movements using braid/fishing line
Bit by bit i'll get there.

Thanks again

Jan

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To guarantee to get aluminium that is flat you have to buy plate rather than sheet. It is a lot more expensive though.

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Heres what i put on thingiverse the extruder im going to use Geared stepper extruder, I have not tried it, but should work with geared stepper motor in the description. I changed the underneath hole to accept the e3d hotend.

nophead Wrote:
-------------------------------------------------------
> To guarantee to get aluminium that is flat you
> have to buy plate rather than sheet. It is a lot
> more expensive though.


Yes that is an option, but as you said the cost is prohibitive.
Have to see how this first one goes, then do some testing.
The acrylic way may be an option as well but I have not found any info yet in regards to what thickness would be adequate.
I have looked at 10mm sheets and it feels a little bit "flimsy", but I guess I won't know before I actually make one.
Then I can compare it to 6mm alu.

Thanks
Regards
Jan

I don't know how things compare to for example my Air 2, but I bought the kit for around 550 euros here in Holland.
It had everything, from the printed parts to pre-assembled a Sanguino 1.3a, 4 stepper drivers, all rods, stepper motors, PCB Heatbed MKII, hotend, bearings. Everything.

So although this was all inclusive, the wiring sucked, so I had to invest in new wiring, a lot of small nuts and bolts were missing, and the wires that did come with the machine required a crimping tool which I had to buy.

All in all, I have stayed well under 800 euros and this includes a few rolls of 1kg ABS.

To be honest, I think when you buy printed parts, they are 'usually' (its what I read and also experienced myself) not the best print quality. So if they are good you got lucky, at least thats how it is over here in the Netherlands.

I think 800 euros for a machine with 4kg of ABS is a reasonable price. I had expected a lot of stuff to go wrong, all that happened was that the sanguino died because apparently *someone* had not assembled the sanguino correctly. I decided to let it rest and not persecute this matter and just pay the shipping cost for sending the sanguino back and paying also for the new sanguino's shipping cost. The parts were however exchanged free of cost. But, the seller accidentally sent my sanguino to another person and I got a new one. With new stepper drivers.

The best solution would probably be to buy all the parts yourself, but you will pay shipping fee for each delivery and lose money that you could've spent otherwise on better tools etc.

Building your own machine always works best, you learn the techniques, and you will learn lessons about the machines, and will be able to maybe build your second machine with great confidence, if you ever come to the point of building a 2nd machine. I would love to buy a Rostock, but for now I'm still learning to use my current Air 2, so it's a little early

Good luck!

Well yeah my estimated b.o.m is around £397, with the fun of sourcing parts and getting cost down, when it comes down to rp parts, quality in my opinion comes down to the fact, is it functional because i can print better visual parts once printers made and calibrated. It also giving me time by doing it this way is making me read learn all I can on 3d printing.
Its crazy how from last week I started too draw a design of a object on piece of paper, but stopped went work, I came home jumped on laptop opened openscad and created the object, went and exported it to stl then measured it in netflab and the dimensions was correct.
Just goes too show how easy and simple this technology is and how sometimes your wanting to design your next thing lol.

FYI ... I purchased an aluminum plate for the Prusa i3 from RepRapSource. It is as flat as I can perceive when checked with the edge of an aluminum scale held across the faces. No visible light peeks through.

Catching up, my i3 build continues. Are they ever really completed? I bought a set of 6 bipolar stepper motors ($10 apiece) because I was concerned that my current X/Y/E motors could be more efficient. As I mentioned, they're hybrid steppers that can only run in unipolar mode with RepRap electronics, so I thought bipolar would be a better choice. (Happy to say they weren't 24V/12V after all, haha, but 5.2V/8.8V. The resistance + inductance are just too high for bipolar.) But the new motors turned out to be much louder and they heated up the stepper drivers a lot more. So I went back to the hybrid motors for the X and Y axes, and it's so much quieter.

This is one thing that's hard to know if you only build one machine, or only acquire one set of motors. They differ a lot in terms of vibration, power usage, etc., and it's hard to know if the set you self-sourced is really the best option. Voltage in the 5V range, torque in the 20 oz-in range for XY and 40 oz-in range for E… The new motors I got are all in the 60 oz-in range, fine for the E motor but overkill for XY. Without trying a few different motors, how would I ever know that my original motors were pretty decent after all?

Since my last post here I replaced my leaking J-head with a new one, and it's working great. I decided to spend a bit extra and go with a TORLON barrel instead of PEEK. Even so, I was able to fix the old J-head with a new PTFE liner. The seller sent me a new one for free. I got it nicely re-wired and re-taped and it's going into our next build, which is a DeltaBot. Along with 3 of those loud $10 bipolar motors. I sold my extra parts sets and motors and recouped some of my build costs. For the last couple of days I've been working on a customized Prusa i3 parts set that I can sell and printing it in natural PLA.

There's some issue with RAMPS or Marlin where USB prints will just stop for no reason, so I stopped using USB to print! I've switched to SD printing exclusively, so I set up a folder on my Mac that syncs to the SD card whenever I insert it. That way I can queue up lots of things to print while the printer is busy. Since I've started printing sets of parts I also wanted to streamline my slicing workflow, so I created a nice AppleScript droplet for the purpose. Drop a bunch of STL files on it, it asks for a Slic3r config file to use, and it slices all those files using the selected config file, naming the .gcode files with the config filename in the suffix. This has been super helpful, as I often tweak one or two things, like retraction, then I need to re-slice a whole bunch of STL files. I can't imagine doing it through Slic3r.app or Pronterface now.

The latest photos of my build and some printed things are posted in my Facebook "Workshop" album. I'm posting videos of my stuff on my YouTube Channel. And I've posted some of my designs on my Thingiverse page, including a few i3 enhancements. I will be adding more soon!

Edited 5 time(s). Last edit at 05/02/2013 12:16AM by Thinkyhead.

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Hello,

I'm also planning to build a Prusa i3. I'm going with a single frame almuminum plate. Now my question is, wheter it is better to leave blank holes in the frame (for connecting the plastic parts, diameter 3,2 for M3 screws) or to drill in M4 threads to directly screw the plastic parts onto the plate.

Has anyone got some advice ?

Thank you!

Why don't you tap the frame holes M3?

This is what the plastic parts are designed for (M4 will require you to drill them to size unless of course you change the hole size before printing them).

I've mounted a couple of single_frame i3 with M3 screws to the tapped frame no problems so far.

Addressing a few points about the material and this piece in particular...

Sheet v. plate in Imperial measured sizes... Thickness is what determines if a material is sheet or plate. With steels sheet is considered a gauge size and measured thickness is considered sheet. Since aluminum is sold by the thickness thinner material is called sheet and thicker material is gauge though there is no formal gauge definition. If one were to use the same methodology as steel, the dimension is which it would be considered plate v. sheet is about .125" or 1/8". A piece of 1/4" (roughly 6mm) AL would be considered a plate though there is no formal definition like steel has. AL plate that thickness in the 370 mm sq the i3 plate is constructed should not flex and should not show signs of warp unless it has been bent or damaged. I'm using 6061-T6 and all the pieces are well within any tolerance for the requirements of this part. Again, if someone has warped material it's from how it was stored or handled. While there are differences in in the types/grades of aluminum used a piece this size isn't going to be impacted unless there is some other issue.

Hole sizing and the .dxf at Prusa's Github... So far I've had more than 10 frames cut using the current .dxf at Prusa's repo. Some users have reported that the holes are too big to tap M3-.5 threads. I haven't found that to be the case, M3 taps. If the holes are being cut from the .dxf on a waterjet that's properly calibrated the holes should be fine. If though, one is looking at a drawing it might be an issue with scaling the viewport of your drawing or the resolution of the printer.

Nice job using AS to consolidate the gcode generation in the tool chain. So far I haven't had an issue with USB printing stopping with RAMPS 1.4 on my i2 machines. I've had a few issues with Pronterface either not sending commands or occasionally freezing when I pause and manually enter a command but no problem with USB printing.

What we have done in our batch of laser-cut frames was to just mark the holes for manual drilling (as laser cut tolerance prevented to have proper size holes to be later tapped).

A drill press, a 2.5mm bit and manual M3 tap did the job.

A bit of extra work but our cost was pretty low too.

Simmerl Wrote:
-------------------------------------------------------
> Hello,
>
> I'm also planning to build a Prusa i3. I'm going
> with a single frame almuminum plate. Now my
> question is, wheter it is better to leave blank
> holes in the frame (for connecting the plastic
> parts, diameter 3,2 for M3 screws) or to drill in
> M4 threads to directly screw the plastic parts
> onto the plate.
>
> Has anyone got some advice ?
>
> Thank you!

if you use the file on the github to get one cut make sure you change the hole sizes to most 2.5mm if you want to tap them to m3, they 3.5mm at the moment and the parts are m3 holes. so you can either change the frame holes or did what i did as i only found out thy was 3.5 when my frame was cut so i tapped them to m4 and changed the rp part holes.

How are the people that are reporting the holes too big measuring and cutting the holes? The plates I've had cut from the current .dxf in the repo have 2.57 mm to 2.59 mm holes. I've easily tapped 3 mm threads into them.

it may have been fixed now but original they was 3.5 but like i said no biggy i tapped them to m4 and changed the parts here what i got so far motors and arduino and smooth bar and threaded rod on the way