Tag: engineering

Adventures in 3D Printer Design Part One of Many

I have a Prusa i2 that I built at a build-a-thon years ago. It works great! Well, it did, but time kept on moving forward like the big jerk it is, and everyone built much better printers.  Now it only works okay. I’m saving up for a move across country so I don’t want to spend too much of my hard earned dollars. Luckily though, past me hated money, so I have a lot of spare parts right now.

My plan is simple. Use what I have lying around all the parts from the prusa i2 to make a printer that’s really above average.

My inventory is thus:

How ain't it broke yet. It is.
My trusty old Prusa i2, run hard, put up cold.
Vitamins not for eatin'. 'cept for the brave of course.
Vitamins not for eatin’. ‘cept for the brave of course.


With these limitations I set out to work. I went through a couple of revisions

A couple of revisions
A couple of revisions




before I figured out what I’m calling my no. 1 rule to printer design (no. 1 rule pending to change).

1. Design the movey hot plastic bit first. It determines the size of everything else.

So, without any more delay. Here’s where I am with the x carriage.

Very Skinny, Very Fancy
Very Skinny, Very Fancy

I’ve done some neat stuff here that I would like to shamelessly brag about. Feel free to shamelessly flay my ideas to shreds in the comments. If we cant be dicks to each other on the internet then what did we invent it for?

Cool stuff:

  1. Did you know there is a RepRap Vertical X-Standard? I did not, but my roommate mentioned it to me so now this fits it.
  2. The center of mass of the whole thing sits right in the middle of the two horizontal 8mm rods. This should let me move it really fast without tearing all the things to pieces.
  3. There are lots of bearings.
  4. It’s got one of those bird shaped quick change filament things.
  5. It’s really really skinny. Right now with the belt tensioner/bearing retraint assembly, this thing is only 56mm wide.

That’s all I have for now.

My next step is to finish the X-Carriage. To do that I need to design the belt tensioners, then print it out and do test fits of everything. Rinse repeat.

After the X-Carriage comes the Vertical Assembly. This will cover my X and Y. I am trying to stick to the same movement as I had before so I don’t have to buy new belts.


How to make soldering fine pitch surface mount ridiculously easy.


This simple tool will change your life. I was lucky to learn how to solder surface mount from a master. He had crafted a tool very similar to this for himself and used it daily.  The design is simple, a weighted pin is attached to a piece of round stock and this holds the part down on the board. Using this tool I soldered an entire surface mount board with no errors on my first try.

When you assemble the tool make sure that you push the bolt through and thread the nut first, because you might bend the threads while filing the tip down. Make sure that the tip has a round point about the size of a standard ball point pen. Any sharper and you could damage/mar parts.final

To use the tool just put the part under the pin and go. It’s that simple, no re flow plates or panavises or any of that junk. You don’t need to worry about tip size for most jobs either. Another plus is that the bolt acts as a heat sink so small parts don’t fry.


You see that tiiiiiny little part. You’re welcome.