Saturday, May 19, 2012

I borrowed this picture from a guy selling it on eBay, this has the servos mounted on the top, so it's not a Version 1.5.  I also opted for black extrusions and red PLA plastic parts.

My goal is to build what I believe to be the best OpenSource 3D printer, the MendelMax 1.5

There are several excellent blogs for this build out there, yet I still had questions.  So I'm going to make this as complete as I can.  It is very confusing to say the least, and not for the faint of heart.  For example I have found 6 different sizes for the smooth rods.  Yikes.  I'll wait to cut the rods when the frame is built and measured.  I also wanted to save some money, which is why I didn't just go buy a kit.  It will take longer to do it this way, but I also get exactly what I want.  In the future, I might even make a bigger MendelMax, so sourcing the parts will be a must.

Here is my parts list.  Since I haven't built it yet, I have no idea how complete it is.  I included Product Description, Part Number with hyperlinks, Unit Price, Qty, Sub Total, Sum, Shipping, Total, Order Date, and Delivery Date.  I went over many BOM, price lists, and product specs to arrive at my BOM.

I'm a step ahead of the game because I already own a small CNC machine.  So I understand things like G-Code, servos, how the data gets to the machine, etc.  I also understand what it takes to make a highly repeatable part...  Accuracy.

So for my build I've opted for 10mm smooth rods and lm10uu bearings (8mm would work just fine for the X and Y axis), but for 10 bucks for the difference between the rod and bearings why not go 10mm?  As far as the smooth rods themselves, the recommended rod is in my BOM.  I highly recommend it.  It is stronger than SS, very hard, and smooth.  This makes it an ideal part for the bearings to ride on.

Now for the hot end AKA extruder head.  Well, I researched these for hours.  The bottom line is a poor hot end will make bad parts, poor print quality, poor repeatability, and lead to a lot of frustration.  I want to print stuff, not mess with the hot end.  So there are 2 units that stand out, the one I choose is made in America, assembled, and can have the nozzles changed out. It's the Budaschnozzle 1.1 nozzle.

I almost forgot the print bed.  I really don't know what I'm doing here.  I know that I need more parts, but I have no idea what yet.  I will be printing a lot of ABS.  ABS requires a hot bed in order to have straight parts.  I also wanted a very flat surface, so I opted for a Pyrex bed.  My initial thought is that it will take longer to heat the Pyrex, but that shouldn't be much of a problem.  As I understand glass will also work, for a little while, then crack.  No thanks, I want a reliable printer, not something else to fix.  The neat thing with Pyrex is that once it's heated up the ABS sticks to it like crazy.  Once it goes below about 80C it almost falls off.  Sweet!!!

I will be adding many pictures.

That's all for tonight.

Here's a picture of mine...