Friday, December 31, 2010

Willow Gets Some Dental Work

I started noticing that my round holes were not quite round, so I checked my belts and determined that the X belt was a little looser than I would like.  I tightened it and started printing again only to discover a horrible noise and  the x motor binding and skipping.  It happened at a few points across the bed but ran fine between them.  I looked around for the problem, what did I mess up by tightening the belt?

Broken Tooth

It turns out all I did was make an existing problem worse.  The x-axis pulley had lost a tooth.  For the looks of the hole where it use to be it had been gone for awhile. (Also note the wear on the teeth from the belt...)

Broken Tooth

Which explains some other strange x-axis noise I could not place.  Lesson learned "Listen to your bot!" if there is a strange noise look around more and look under things.

The easiest way to fix this, and keep my nice pulley, was to remove the pulley, flip it over, and put it back on.  Easier said than done...

Once I started looking at it closer I realized why the tooth broke.

Hollow tooth


Four of the teeth are completely hollow.  I am not sure what infill settings we used when printing the gears.  But the 4 that are are 45° from the infill direction have none in them.
I then became concerned about my other pulleys.  I checked and they all have the hollow teeth but Z and Y both have all of them still.  But I will have to keep an eye on them.

How to reinforce the pulley so that it won't break again?
It turns out the holes were big enough that some of my waste PLA (0.5mm) would slip down into them.
0.5mm waste PLA (for filling the void)


So I cut 4 pieces, mixed up some epoxy and glued them in.
Pulley with voids filled


Here you can see the reinforcement PLA inside the teeth.
Pulley with voids filled

I then pressed the pulley back on with a bar clamp.
Pressing pulley onto motor

Fixed motor


I then reinstalled it on Willow and re-tightened the belt.
Fixed motor


Back in business and printing again.  The x-axis is quieter now, which brings my back to "Listen to your bot!" if there is a strange noise look around and look under things.

A final thing to note is even professionally printed pulleys will eventually wear out.

Thursday, December 23, 2010

Willow gets a new light

I had a light I made using perf board that fit on the old x carriage.
Unfortunately it would not fit on my new x carriage, so I designed a board with KiCad and had it made using BatchPCB.
The idea being to have 4 different sets of 3 LEDs.   I chose White, Orange, Green, and UV.

The UV is very cool with the Ultimachine Blue PLA.

I originally designed it to have the LEDs wired in parallel but after getting the boards I realized that was a bad way to drive the LEDs so I changed the board by breaking a few traces and adding a few jumpers.


Saturday, December 18, 2010

A Holiday Prusa Mendel

I found http://www.thingiverse.com/thing:5002 and the novelty of this holiday remix of the Prusa Mendel was enough for me to try printing one.  Kliment is making a holiday themed build plate for each day starting on December 2nd and ending on the 24th.  You can print one plate each day and will have a Prusa by Christmas.

All parts through day 18

I have pictures of all the parts I have so far here.

I like the simplicity of the Prusa but am taking a slightly different approach to RepRap simplification with my Integrated Parametric RepRap  (more on that soon).

Sunday, December 5, 2010

More Plastic, a Fourth offspring, and an update to IPR

I used the money I made selling my first three Mendels to buy more PLA from Ultimachine.  I bought 2 rolls each of Green, Blue, White, Silver, and Black.  Someone that I met at Metrix: Create Space is buying one roll of the Green from me.
Willow is happily restocked with plastic and the Green was used to finish a fourth Mendel set that will be listed on eBay in the morning.

Certificate

I also made some progress on my Integrated Parametric RepRap work and posted a new version of the OpenSCAD files on Thingiverse.

Sunday, November 28, 2010

First pre-release of Integrated Parametric RepRap

I just uploaded the first pre-release of my Integrated Parametric RepRap OpenSCAD files.  Currently it does not make anything printable but what it does do is "build" a parametric frame based on the settings in the DNA file.

The core files contain the following:
IPR_DNA:
All constants and calculations, the constants define all the possible things that make a specific robot unique. (ranging from desired build space to fastener and bearing sizes)
IPR_func:
All "standard" modules, such as motor mounts, bearing mounts, hardware models, etc... currently this file "builds" the main frame out of the hardware specified in the IPR_DNA file.
 


The following pictures show the frame with a 100x100, 150x150, & 200x200 build space with normal Mendel sized hardware (including a NEMA17 Z motor on the left).
100x100
150x150
200x200
This picture shows a 300x300 build space with larger hardware (608 guide bearings and 12mm rod).
300x300
This should give you an idea of the flexibility I am building into this design.


I plan to keep ALL constants and calculated values in the DNA file and everything else in a few files that call the DNA and func files.

Here are my current rules:
  1. If it is a constant it lives in the DNA file.
  2. If it is a calculation that effects parts (not positional calculations but dimensional ones) it lives in the DNA file.
  3. If it is a module that anything else needs to call it lives in the func file.
The goal is to eliminate redundancy and simplify the whole process of generating a robots files.


For more information visit the main documentation at:
reprap.org/wiki/Integrated_Parametric_RepRap

Wednesday, November 24, 2010

More Hollow Prints

After last week I am, at least temporarily, hooked on hollow prints.  So I downloaded MakeHuman and did some experiments with making my own human forms.  I then printed a male and a female.

MakeHuman female test 2 MakeHuman male test 2

After examining them I determined it would work better if I printed them upside-down.  So I re-trimmed the files and printed them again with very nice results (the above pictures are of the upside-down prints).  I have uploaded these to Thingiverse (male and female) and hope others are inspired to create more human forms to print.

I also printed a large hollow version of a 3D scan of my face.

My face scanned and printed

Be sure to check out more pictures on Flicker.

Saturday, November 20, 2010

My Attempt at a Hollow Woman Print

After seeing a picture from Erik de Bruijn of the pink panther woman printed on an UltiMaker with no infill I thought I would try that and see how it turned out.  Here it is:
 
Mine is not as smooth as Erik's as it has pause points that leave little blobs... It is still a very cool print.

Sunday, November 14, 2010

3rd Mendel Set for Sale & More About Moustaches

Willow has recently completed it's third complete set of Mendel parts! This set was printed using mostly Blue Translucent, UV Happy, UltiMachine PLA.  I did run out of that PLA before finishing the extruder and a few of the y bar clamps, so the those are printed in the Natural PLA.


They are on eBay currently and close on Nov 18, 2010 at 5:56:54 PST.  I have cleaned them up some but have not reamed the holes.  They come with a certificate of lineage (for anyone tracking that) suitable for framing.  Check out the eBay listing for more information.

I also have a collection of items on etsy that I am selling to help support Movember.  During the month of November I am donating 100% of the sale price of all of these items to the Movember Foundation.  Some of these items were 3D printed on Willow.  If you want to see my slow growing moustache updates or donate money directly to Movember you should visit my MoSpace Page.

Sunday, November 7, 2010

Movember Moustaches

I took a small detour from Mendel reproduction to explore printing Moustaches (I am participating in Movember).  I first made a design that works very well for a larger Moustache but started to behave strangely in RepSnapper as I scaled it down.  The slices would start getting too small and the part would have huge steps.


So I tweaked my design and made a second version that worked a little better (more rounded points and slightly better geometry).  RepSnapper still had problems with strange layers with this version.

I ultimately made a third version with simpler geometry.  This version worked very well for small Mo's (2nd-3rd image below) but RepSnapper did something even stranger on the versions with holes for a necklace cord or key chain (top two).
The geometry is just chopped at the hole.
I took the STLs into MeshLab and did some smoothing and face re-simplification and was able to get something that did not have sharp corners and prints well in RepSnapper (even with the holes - see bottom two images above).  It is probably time to start learning how to use something more robust than RepSnapper (like Skienforge...)

Saturday, October 30, 2010

Second Set of Mendel Parts on eBay

Willow has recently completed it's second complete set of Mendel parts! This set was printed using Blue Translucent, UV Happy, UltiMachine PLA.



They are on eBay currently at a $76.00 bid and close on Nov 01, 2010 at 08:06:10 PDT.  I have cleaned them up some but have not reamed the holes.  They come with a certificate of lineage (for anyone tracking that) suitable for framing.  Check out the eBay listing for more information.

Wednesday, October 27, 2010

Makerbot Halloween Contest Winning Entry!

Just a quick shout out to my co-winner in the Makerbot Halloween contest PaSuTX with the very cool Bat Mobile.  My winning entry was my parametric spider web design.

I look forward to getting my glow-in-the-dark ABS and want to thank all the fine folks at Makerbot for the cool contest.

Saturday, October 23, 2010

Leaking Heaters...

My current heater was working very well extruding PLA at 230C, which seems a little high but the parts are coming out nicely.  It had started leaking like many of the others I have seen with PTFE insulators.

Then it finally plugged up...  I tried cleaning it out without disassembling it, but this did not work.
I then disassembled the hotend to find the plug and remove it.  During this I discovered that the wood retainer I had been using was starting to char away.



So I began work on a new design that I had been thinking about for a while.  This is based on the BfB hotend that many people like but can be built with only a drill press, hacksaw, rotary tool (Dremel), and belt sander (I plan to post directions soon).

I also found an excellent source for bootlace ferrules.
You can buy these at craft stores in the jewelery section.  They are designed for crimping necklace cords and this bag cost $2.99.


So far I have done hand push tests and can easily push filament at 165°C.


Now I have to change out my x carriage for  larger one (http://www.thingiverse.com/thing:3594, which I already printed before my failure).

Sunday, October 10, 2010

Black Light PLA - Call-out for Pictures

I have been playing with UltiMachine's UV glowing PLA for a while now and have made a variety of things.  Here are some pictures:
and the picture that was such a hit back in June:

Now that I have completed my first Mendel set, I think that next set I print and sell will be made from this PLA (A UV Glowing Mendel will be very cool...)

I even have a Moai necklace made with it for sale on etsy.

Are other people printing with this PLA?
Are there pictures?
Please leave comments with links