Folger Tech 2020 Prusa i3 – The Build – Part 1

 Ok, this is going to be a bit more text heavy than I had wanted. But once I got going I forgot to stop for photos and I basically had one day that I could dedicate to the project with minimal interruptions so I just dug in and focused on the build instead of trying to really document the build.

Since then I’ve been having so much fun printing things that I haven’t found the time to write up this post.  But I’m wanting to talk about the stuff I’ve been printing and feel like if I do that I’ll never get to this post.  So before I forget all this it’s time to put it down for posterity and to help anyone else who’s building one of these “Kits”.

First off.  If you aren’t mechanically handy and don’t tend to toss out the instructions first thing when starting a project…I’d STRONGLY suggest doing some major homework before ordering this “kit”.  I tend to put kit in parenthesis when discussing it because this really is more a box of parts that can be used to build a printer than what I would consider a kit.

Major Gotchas:

  • Folger kits are notorious for missing and broken parts.  I was excited to find no parts missing from my kit!  Only to later discover that I was missing parts it’s just that the parts included and the instructions seem to have little to do with each other.
  • I’ve heard a lot of people report bad RAMPS boards and Arduino boards – mine were nothing spectacular but they work.  The LCD I ordered however was another story.  Half of the pins on the connector for it weren’t even soldered – once I soldered them it worked fine.
  • The thermister on my hotend was inoperable out of the box and so was the fan on my extruder.  I’ve heard several other people get bad thermisters as well, the design used here isn’t great (more on that shortly.)  To their credit Folger was quick to respond to my e-mail about this and also quick to send me not just a replacement thermister but a whole replacement hotend (and fan.)
  • Some of the hardware choices are questionable.
  • Some of the instructions are flat out WRONG.
  • Some of the instructions aren’t wrong…but are “sub-optimal”

Thankfully there is a large user community on the reprap forums, On RcGroups, On FliteTest,  The Moosteria blog, the #folgertech and #reprap channels on freenode IRC, and probably a few other places I keep forgetting about.

This addendum to the Folger instructions created by IRC user NeutronFluxLabs is also very helpful and will help you avoid most of the blatant mistakes in the Folger manual:

I read all of the Moosteria blog, all of the RcGroups thread and all of the FT thread – I only read the first 10-15 pages and last 10-15 pages of the reprap thread…their forum drives me crazy.  But there’s a ton of good stuff in there so I’m slowly working my way through the bits I skipped.  When building I kept a notebook open with the Folger instructions but I printed out Neutron’s addendum and referred to it constantly.

The Build

With that all out of the way let’s dig in on the things I noticed and would add to the instructions.  First sign of trouble was on the very first step of Folgers instructions (Technically substep 2 of step 3 but the first time you actually put something together).  The M4 bolt heads aren’t big enough to really fit the 2020 angle brackets properly!  A few washers are a VERY good idea here.  I admit I keep forgetting to add them.  I just pushed the bolts all the way to the edge of the brackets where they can grab just enough of the brackets to be somewhat usable.

First two problem issues. On the left the M4 bolt head is too small to reliably hold the bracket. On the right the M5 bolts in my kit were 10mm long not 8mm as specified in the instructions.

Two substeps later and I hit my first “missing” part.  The instructions called for M5x8mm bolts…I didn’t get any in my kit and there weren’t any even listed on my hardware pack.  I did however have some M5x10’s in my hardware pack and nowhere else in the kit are M5 bolts called for.  I had heard other people complain that the M5’s were too short so I’m guessing this is a correction on Folgers part that just didn’t make it into the manual.

Another common problem is that the SK8 brackets don’t grip the 8mm smooth rods well.

The infamous SK8 brackets.

I’ve heard a lot of people have to add tape to the rods to get them to cinch, or squeeze the brackets with pliers.  I was able to get them tight thanks to some nice allen wrenches and more torque than I’d usually use.

Thankfully from there the rest of the basic frame went together without any major issues.  There were a few more times I had to stop and figure out which hardware to actually use instead of what was called for but mostly it all just made sense and the manual and addendum had me covered.

About 3 hours into the build, most of which was actually sorting and organizing parts.

By the end of the first night I had my Y axis assembled, the upper frame installed and was ready to dig in on the X carriage.  The last thing I did on the first night was to install the Z axis motors and this is a BIG GOTCHA. If you follow the instructions your printer will not work well if at all.

The instructions call for using 2 bolts/T-nuts in the top extrusion and 1 in the vertical extrusion.  DO NOT INSTALL THAT 3RD BOLT!  You will not get your Z axis chromed rods parallel if you do.

No third bolt/nut in the vertical extrusion. Just the two in the top one.

Right now this isn’t important…but it will be when you install the Z/X axis.

The only other thing I did at this point that wasn’t in the instructions was when I put the build plate on I left the bearing carriers kind of loose so I could slowly snug them up as I aligned everything.  But I left most of that for the next day.

End of the first night.

I figured this was a good stopping point for the first night, it was nearly 1AM and while I could have pushed on and finished the mechanical build I decided to get a good nights sleep so I could devote the whole next day to doing it right instead.

And so that’s where I’ll also end this post.  I had just over 4 hours into it at this point and it was starting to look like a printer.  The next day it took me close to 6 hours taking my time to finish the mechanical and electrical assembly….and then almost another 6 of figuring out firmware and software (and dealing with computer issues.)  So that should be plenty for the next post, or two 😀

Tags: , , , ,

Leave a Reply