Thursday, April 28, 2011

Getting Help Building a RepRap Machine

There is a lot of help available for people building a RepRap machine. First thing I did to find help was to use Google and put together "reprap" and "kalamazoo" as search terms, since I live in Kalamazoo. I didin't find a lot with those terms, but if you were to do that now, the BuggerIT blog is first, second and third in the results. Hopefully this blog will be a resource to anyone in Kalamazoo, Michigan looking to build a machine, and of course anyone local who reaches out to me will get a response. I'm excited to help spread the word here in town.

You can also try to locate a local hackerspace. Members of any such club will almost certainly have heard of the RepRap project, and may even have a working one for you to see in action. In Kalamazoo there is a group that might roughly be called a hackerspace, but I couldn't find any evidence of RepRap or desktop/home CNC in anything they had online. Also, it just didn't seem like a place I'd like to go, so I guess I'll have to start my own hackerspace in Kalamazoo that's more my style!

If you expand your search to the state or provincial level, you will find some level of support there. In my case there is a Google Group called RepRap Michigan which is somewhat active. I have posted there and gotten responses. I think I found the group through the RepRap forums or the RepRap Map.

Expand your search from there and you can go straight to the global community. The first stop, of course, is the web site itself. The videos available with the build instructions for the Prusa Mendel at least are very instructive. The best place to look for help of all though, is the RepRap IRC channel. On the IRC channel you will find all the people who are actively involved in the RepRap scene, and because it's promoted heavily as a source for help, also by beginners like you and me. I just spotted prusajr himself.

Other recommendations:

Project Update:

The video above is a test of what the video quality should be when I get started with project documentation. I'll have a second camera over my shoulder looking down on the table for a detail shot. My plan is to video everything and go step by step through the process in excruciating detail. The videos on the assembly page by RepRap Log Phase are great and all, but I think they move too quickly and use terms an absolute beginner might find intimidating and unapproachable.

Tuesday, April 26, 2011

Hunting Hardware for the Prusa Mendel

Like with the printed plastic parts my original intent was to try as best I could to acquire the materials locally instead of relying on the Internet to deliver the pieces to my house. As with the printed parts, initial efforts proved frustrating and in the interest of getting on with it, I wound up on the Internet anyway.

My parts list, as shown in the parts document that accompanied the assembly instructions and printed parts.

It wasn't a complete failure. First I started at what is the closest thing we have to a mom-and-pop hardware store of ye olde days, True Value Hardware. There I got zip ties, 5/16" nuts and washers, plus a handful of #8-32 nuts and washers, and one M8 x 50 Hex Hobbed Bolt and nut. I'd asked her for two nuts but didn't realize she'd given me just one, so I'll have to go back. I could have gotten the 5/16" threaded rod there, but they wanted something like $21 for one, 6' rod. Umm, no thank you. McMasters had them listed for less than $5 ea.

Total spent at True Value: $17.50

What it would have cost online: $23.75 before shipping

Lowe's was my next stop, and there I got threaded rod, and the fender washers.

Total spent at Lowe's: $19.16

What it would have cost online: $31.91

So far, so good. But those were the easy parts. Nobody up to that point knew what drill rod was, and nobody had any. The guy at Lowe's did give me two important tips, though. He was concerned that I wouldn't be able to thread a nut on to the 6' length of 5/16" threaded rod I had him cut in half, because, he said, the cut messes up the threading where it's cut. To avoid that problem he suggested threading nuts on the rod on either side of the cut and then wind them off to smooth out the thread. Fantastic idea. Second, he told me there was a fastener store in town called Fastenal, and they might have the other parts I was looking for.

Fastenal had some of the parts, and ordered some more which should arrive Friday, but some parts are still missing. From Fastenal I finally got the drill rod (well, 2 of the 3 pieces I need), M4x10mm bolts, #4-40 x 1” cap bolt, #4-40 washer, and #4-40 hex nut.

Total spent at Fastenal: $50.77

What it would have cost online: $21.84

Ouch. So, the score for this round is: $87.43 for the home team, $77.50 for the away team.

Online is probably only beating local by the amount of shipping, or less, but as I get to some of the parts they had to order special for me, the price differential increases. For the metric bits listed under the Wade's Extruder section of the build materials, I will definitely have to go to McMasters if I want to keep the cost down. The brass bushings were the hardest to locate nearby. I got a couple leads from Fastenal, but it'll just be easier to get them with the other screws and nuts I need for the extruder.

Friday, April 22, 2011

Mendel Printed Parts Arrived

The printed parts for the Prusa Mendel arrived today, and as you can see, I'm very happy about it. It was very quick in arriving, and they came packed in a ziplock, surrounded by the air-bag wrap you get from Amazon, and everything seemed to be in ship shape. I'd received the parts list and assembly instructions specific to this printing of the parts via email from the eBay seller. This is important because the project is constantly changing and you need the instructions that go with the parts being sold. I was sure to check the parts I received against the parts listed in the assembly instructions to ensure I had everything.

Overall the quality of the parts were satisfactory. Some were better than others, and all had a glossy, corrugated surface on one side, probably from the heated bed on the manufacturer's Thing-o-matic printer. 

The side opposite of the glossy finish was the expected pattern of extruded plastic, criss-crossing the surface. The burrs and flash that appears on the part was also expected and I'm sure will be easy to clean up when I get started.

This apparently is a tricky part for the Thing-o-matic. The glossy "bottom" of this part has some apparent defects and while this bothered my wife, who thinks this part wasn't very well made, I'm not so concerned. She's probably right that I wouldn't want to stress it very much for fear it will break, but that's likely true of most of the parts. I will want to print extra parts as soon as I get it running so that if something does go wrong I can repair it quickly without having to buy a part off someone online. Also, the large hole on this particular piece is especially messy. I'm not sure what the issue is there, but it's probably not a big deal. I might dab some glue in there to firm up the filaments and then ream the hole.

The gears are especially important, and I imagine somewhat difficult to get right. This one is really quite nicely done I think, but the smaller gears are a little less well defined in the teeth area, and vary from the diagram in the instructions in that the hole where the tension screw goes, so the gear can grip the motor shaft is not complete on the outside. The part of the hole on the inside edge of the slot for the nut that threads the screw is complete, so it should be fine, but perhaps I might try printing better small gears and replace them immediately when I get the chance.

Some pieces were printed very close together, and come stuck together. Again, not an issue, but the smallest part shown here might cause me a bit of trouble if I'm not very careful. They are quite firmly stuck together. 

I won't have time this weekend to get the hardware, but that's the next step and I'll hit Lowes on Monday.

Wednesday, April 20, 2011

Plastic Parts Purchased

The project has begun in earnest. Tonight I completed the checkout process on an eBay item with the following description:
RepRap Prusa Mendel with Wade Extruder - SAE + EXTRAS!!
This is a complete set of all the Prusa Mendel printed parts with the Wade's Extruder.  This set uses SAE nuts and bolts instead of metric so they are cheaper and easier to buy anywhere in the USA.   
Everything was printed off of my Makerbot Thing-O-Matic,  These still need to be reamed, but are extremely clean and very high quality (go check out some of the other Prusa's on E-bay, not very good quality!) pieces made from strong ABS Plastic.  For more information and assembly instructions see or 
Please e-mail me with any questions. 
I will ship this with either the bushing holders for the store bought bushings or a set of Printed Bushings printed out of ABS Plastic (Sorry, I'm out of PLA for now).  Let me know which you want or if you want them both I can throw them both in. 
This set also includes a full build instruction manual to walk you step by step through the build process of your prusa mendel.  I will also include a Parts list of all the other parts needed with their part numbers and the suppliers.
Seller info: 
elderfarrer2hy7 ( 82)  
100% Positive feedback
The total price, shipped to my door: $102.55

The seller is located in Idaho. I was hoping to find a Michigan supplier so I could pick up the parts in person and maybe see a demonstration of a working unit. Although I have had good luck finding help and people in Michigan (and Chicago) who are working on building Mendels, nobody had any parts to sell and nobody has yet been able to tell me they have a working unit. Mostly they are like the above seller who have started with Makerbot Thing-o-matics or the like.

I'm really looking forward to getting started. The parts list with supplier information will be handy and was a selling point for this eBay listing.

Thursday, April 14, 2011

RepRap Project First Thoughts

Introduction to Mendel from Rep Rap on Vimeo.

You've decided you're going to make a RepRap machine? Great! Now what?

The first thing you're going to want to do is decide which RepRap machine you're going to make. It's pretty easy to say, "the most recent version," because that's the Mendel. However, it turns out there are a number of versions of the Mendel to choose from. Sells, Isaac, Prusa, Huxley, these are all the names of different flavors of the Mendel. They all have the same basic shape, but they vary in some subtle ways.  The Sells Mendel with Gen3 electronics is pictured on the RepRap home page (the video link) and is featured in the introductory videos, etc. It's named after Ed Sells, the guy talking in the above video. He developed the Mendel and the Sells Mendel is the original. The Sells Mendel has some drawbacks, however, mainly that the complexity of the design makes it more difficult to dial in and get working than other variants.

The hot variant right now is the Prusa (pronounced PROO • shuh) because it has fewer pieces, is easier to build, and is more standardized. It too is named after it's chief developer. I found this video, which compares the two models.

These just give you the basic frame and mechanics of the machine. You will need to add the extruder,  electronics and motors after that. There are a number of electronics packages to choose from. Right now the hot stuff is the RAMPS configuration. I understand the Wade Extruder is the thing to get in that department. The motors are just stepper motors of a certain specification, which is described in the plans.

Step one, pick a variant, electronics and extruder. For me, that's Prusa with RAMPS (w/ special attention to getting it with the SD card reader) and Wade Extruder.

Kalamazoo RepRap Mendel

Thanks to the generous support of Maryellen Hains, this summer I am going to build a 3D printer. Specifically, I'm going to build a RepRap Mendel, an open source 3D printer. This printer will be made available to area artists and makers somehow, though the particulars of how that will work are yet to be determined. I feel it is likely, though, that it will find a home at the Kalamazoo Institute of Arts.

Hearing first about the RepRap project maybe three years or so ago, around about the time I subscribed to Make Magazine it drew my attention. It was still a bit sketchy at the time, however, so I put it on the, "wait and see where this goes" list in my brain. Then Make Magazine podcast person Bre Pettis started MakerBot and produced the Cupcake, but I was somewhat turned off by the fact that you couldn't use a Makerbot to make a Makerbot like RepRap was trying to do. It reminded me to check in on the RepRap and they are on their second version, the Mendel, and that looked very exciting. I put out feelers for support by founding a group for Kalamazoo makers and suggested we build a Mendel as the kickstart project. I didn't get a lot of takers.

The last day of my KIA web design class (which I teach) was a review and wrap up day, and a little loose format-wise. Someone got me going on CNC machines and I brought up the RepRap. The whole class was engaged on the subject, to my surprise. Maryellen in particular, who was taking the class, seemed very interested in the possibilities of 3D printing for jewelry and volunteered to participate if I could get some other people to join in. Later it occurred to me to ask her to help out in a different way.

At Jim Riegel's retirement party tonight I sat her down to talk her into helping me get a grant and/or KIA backing for the project, intending it to be a project for the KIA around which she and I would develop classes to be taught there, and out of the blue she decides to fund most of project all by herself and wrote me a check on the spot!

So now I'm building a Mendel this summer. Ordering parts this week!