Saturday, December 11, 2010

Wandering back and forth

I'm not abandoning this project... I'm just slow. The cartesian portion is more or less complete, but I ran into a snag on the electronics. I was going through the electronics bits I purchased for this project and realized that I made an error when ordering the parts and boards for my stepper motor controllers. I bought 3 of each of the parts lists for the through hole soldering parts and 3 of the surface mount controller boards. So it's all, incompatible. I'm not really sure what to do. I could:

1) I could just buy the appropriate surface mount parts.
2) I could have someone make me a board compatible with the old electronics
3) I could purchase an entirely different set of electronics and move ahead with them

Wednesday, February 11, 2009

Printed Stickers but rails still problematic (my fault)

So, after trying about a bazillion different ways to print the stickers, I finally exported them from Google Sketchup as an image and printed that from Corel Painter of all things. It was really a royal pain in my ass. Not blaming anyone but me....

So, I got them home and attached to my rails... And decided that I just couldn't wait to drill them, so I went out into my studio to do the drilling. We've got someone renting the room just above the studio, so I was trying to be quiet... Ha ha, quietly drilling aluminum. Not really two things that go together. I was so loud that I was worried about waking up my fiance in the next building over...

Needless to say, I'm not Mister Handyman or anything and I was distracted by trying to keep it quiet... SO the holes came out pretty darn wobbly. Tomorrow will be Fun with Files.

On other fronts, remember to be gentle with the acrylic. Especially the stage bearing assemblies. I tried putting the nails through them and three of the four cracked. I know there is at least one extra in my box of parts, but this is ridiculous. I will probably try to get away with gluing the ones that dont end up getting replaced.

And last but not least, I over tightened a screw putting on the PTFE bearings and broke a small piece off the z stage where the screw goes it. You'd think that the earlier incident witht he bearing assemblies would have made me cautions, but.... apparently not. again, I think glue will do the trick.

So, my advice is: Go slow kids! Take your time...

Tuesday, February 10, 2009


Stalled by stickers... Say it ain't so.

Okay, maybe they are working for other people and I realllly hope they are, but the stickers for drilling the holes just aren't working for me. The first problem was that the link from the main mcwire page points to the old version of the files. DO NOT USE THE 1.2 version. They aren't the right spacing to fit the holes on the rails. I let Zach know, so hopefully people later won't have the same problems.

However, then I got the 1.2.1 stickers files and they just WILL NOT print no matter what I do. Even on Legal sized paper, they print cropped to letter size. Argggggh. So, I've been trying to get the pieces to print from the DXF files... No luck so far, but I'll keep you posted.

Friday, February 6, 2009

More work then disaster and immediate recovery

My aluminum rails haven't arrived yet from Speedy Metals, but I still wanted to move ahead working on the cartesian bot, so I started assembling bearings assemblies. Everything went smoothly except that I haven't been able to get enough 1" machine screws. The local hardware store was out, so I ended up buying 1 1/4", assuming that I'd either be able to replace them later or that I could find a place where ther extra size didn't matter quite so much. I ended up using 4 of them to attached the bearings to the bearing assemblies for the z-stage. It seems like the extra size will be fine there.

I was trying to be very careful with the laser cut parts as I assembled the bearings assemblies, but I got a little distracted and went to tighten one. It was already pretty tight but I gave it one last little push and set it down. A few seconds later, after I'd already picked up the next one, I heard a small CRACKing noise. I'd over tightened the machine screw and the acrylic broke! Thoughts about humble requests for extra parts filled my mind and I finally decided that between glue, tape and the good will of others, I would end up just fine. Then a few minutes later as I was moving some bags of parts around, I noticed it! There are extra bearings in the package of parts from At least one of each kind of bearing arm. AWESOME! thank you you made my day!

A couple more build notes:

Springs: Don't just buy all 4" springs. In one case they were too long. I think one would be better off waiting to purchase springs until one knew how large they should be.

washers: When putting the bearings assemblies on the stages, howmany washers should you use? Should you use any? I used one between the two peices of plastic and another between the bearing and the bearing assembly, but that seems to make it pretty high off the stage. I will ask this question on the forums, of course. Also, how tight are they supposed to be?

Machine Screws: This is one of those things that is goign to keep bugging me until I figure it out. In all the pictures, it seems like the screws they are using are different. At first the parts list said 3/4" screws. Then I noticed that they were too short and so I bought 1" screws (which is what the instructions actually call for). But even still, in the pics, the sizes just look different. Is it possible that the screws he was using are actually 7/8" long? It's certainly possible.

Took some photos last night. Will post them soon.

Thursday, February 5, 2009

5/16" x 3/4" machine screw... Nope.

The parts lister list 5/16" x 3/4" machine screw as one of the most extensively used fasteners in the project. However, they are too short!

I've been getting all my parts together and wanted to jsut make a little progress, so I decided to bolt a few of the bearings to the stages. I got my 3/4" machine screws and oops. They're just too short. The instructions say 1" but the BOM says 3/4".... Argh. I guess there's a trip to the hardware store in my future.


Tuesday, February 3, 2009

Sourcing the Parts has a Parts Lister that did a good job of laying out what will be needed to build my repstrap. Somewhere on the page, they say that a repstrap should be buildable for about $250US. That amount seems laughable small, but perhaps it is possible if you did everything yourself and sourced parts carefully. As for me, I work a fulltime+ plus job and am planning a wedding for this summer, so I really don't have a ton of spare time to do all that work myself. Also, I'm not sure that my skills are really up to it. So, I am specifically choosing to substitute money for time where some of these parts are concerned. To that end, I've ordered parts as follows:

Laser cut cartesian Robot parts from
The parts are really nice looking. Mine are an opaque green, rather than the clear acrylic you can see in all the pretty pictures from instructables and reprap. I also paid the extra $20 to get the holes countersunk.

Electronics kits from
3 ea. Stepper Motor Driver v2.3 Raw PCB
1 ea. Arduino Breakout Shield v1.4 PCB
2 ea. Skate Bearings
1 ea. Temperature Sensor v1.1 Kit
1 ea. PWM Driver v1.1 Kit
3 ea. Opto Endstop v2.1 Kit
1 ea. GM3 Noise Suppressor v1.0 Kit

They were out of the stepper motor kits, so I had to source those out on my own. Luckily, the parts lister makes that super easy. So these electronics pieces and the laser cut parts were about $200.

Pre-Cut Aluminum pieces from
So easy! The shipping was a little high, but I have a suspicion it's because I ordered my threaded rod from them as well (not precut) and shipping 3 foot long rods are probably more expensive. At any rate, the total for this was about $46.00 (with $14 of that being shipping)

As you can see, I'm already hitting the $250 mark and I haven't bought any of the hardware or the remaining electronics components. (Not that I really care about the price at this point. $250 seemed pretty optimistic from the get-go. I was thinking that it might end up around $500 with all the stuff I'm getting other people to do for me.

Machined thermal Extruder parts
There is a fellow on the For Sale forum who is machining and selling thermal extruder parts for about $41 including shipping. You get:

1 brass nozzle with a 0.4mm orifice
1 brass heater barrel
1 PTFE thermal break
1 steel drive screw
2 brass half-bearings for the drive screw
2 nuts for the steel drive screw

Find it here:,20261

Electronic components
The electronic components for the 3 Stepper Motor drivers were purchased mainly from Great website. Such an easy cut and paste process from the parts lister. When I got the final list on Mouser's site, I noticed a few things that were out of stock and a few that had outrageous minimum orders. So I purchased them from Jameco and Digikey. Wow, things move fast. I just went back to the parts lister and someone has updated it with things that are in stock. Crazy internet! I also saved about $30 going through the list and comparison shopping the most expensive items.

At any rate, for those of you keeping track, and by "those of you" I mean me, I spent

Digikey: $10
  • Trimpots
    It was $2.50 for the parts, $7.50 for shipping. I didn't order these because they were out of stock on mouser and I didn't have the confidence to find exact matches from another manufacturer on their site. So I ended up getting beaten up on the shipping. Also, now there is another trim pot listed on the parts list which are available.

Jameco: $40.00
  • Drivers
  • Controllers
  • Breakaway headers (which aren't on the parts list anymore.)

McMaster: $33.90
I ended up ordering the teflon strips and the silicon tubing from McMaster's because I thoguht finding them would be hard, but then I added a few other things to the list that I wasn't persistent enough to find around here.

  • Teflon Strips
  • u-clamps:
    If the parts list had been a little more clear, I probably could have sourced these locally too. Instead, I bought a box of 50 from McMasters.
  • 1/2" machine screws
    should have gone to a better hardware store
  • dSilicon tubing:
    Does this really need to be silicon?
  • M5 screws and accessories.
    Could have gotten these locally too, but I forgot to put them on my list when I went shopping.

The rest of the stuff I got and Home Depot or OSH.

One thing that caused me some trouble was the Flange for the vertical base. The only ones I could find for 3/4" pipe were too small. The lasercut piece is drilled and counter-sunk for 1/2" screws and the pre drilled holes were too close together. However, the 1" pipe flange was perfect. I suspect that the McWire plans originally used 1" pipe. At any rate, I bought the flange for the 1" pipe and a little coverter geegaw to downsize the hole from one inch to three quarters.

Also, 1/2" machine screws are not avaible at either Home Depot or Osh. I imagine that I could have found them at some place smaller, with less emphasis on the most generic items possible, but instead I just ordered them from McMaster.

I spent about $50 on various parts of the structure at Home Depot and another $30 at OSH.

So I think I'm around $500 in on this project. I still need the Stepper Motors and maybe a couple things for the extruder. But I'm about where I thought I would be.

Monday, February 2, 2009

Ready, Set, Go.

Since I first heard of their existence, I've longed to have a 3d printer of my own. The ease of moving from thought to realization of that thought is exhilarating. Recently, DIY 3D printers have been showing up on Instructables,, and many other interesting places, I was entranced, but daunted by the complexities of the task.

I've known for a long time that my enthusiasm often takes my better judgment out behind the wood shed and shows it a thing or two about keeping quiet while daddy is speaking and so it was with this.

I've begun ordering and purchasing parts for my 3d Printer. I've decided to go with the McWire Seedling plans from

I am, needless to say, very excited about this.