Tag Archives: Rick

Christmas, Birthday, etc

Posted on by

It’s not that I’m not materialistic or a complete stoic.  It’s just that my interests are so simple, narrow, and specific there just isn’t a whole lot I require out of life.  But for other happy and fortunate life complications1 I’d live in a studio apartment almost completely devoid of furniture except for a futon, small table, one (perhaps two) and book shelf.  Give me a library card and a laptop and I’ll show you a content man.  For example – one of my hobbies is origami.  Which boils down to basically a lot of paper. 2

While this means I’m easily content, it means those family and friends are frustrated at the thought of having to find me a gift. 3  So, for basically the first time ever I’ve put together a wish list with stuff I would love to get (in rough order):

  1. aka family [↩]
  2. A hobby which, hundreds of years ago could only be practiced by those precious few who had access to a luxury such as paper, can now be practiced by anyone in reach of a paper recycling bin. [↩]
  3. 500 sheets of A4 bright white multipurpose paper???  Score! [↩]
  4. Since I have none of the equipment or skills to perform SMT soldering [↩]
  5. Someone mentioned the modular thermistor set ups don’t detect temperatures properly – about 10 degrees too low?! Update:  Rick of MakerGear clarifies this was the result of a ring terminal mounted thermistor.  His modular thermistor kit pictured at the bottom of the this page shows that this kit allows you to make the entire thermistor attachment far more modular by covering it’s terminals in PTFE sleeves and then adding a connector.  This only makes me want this kit more.  Thanks Rick! [↩]
  6. Preferably one with George Plimpton’s face [↩]
  7. That’s a Simpson’s reference, FYI [↩]

Adventures with PLA temperatures

Posted on by

Kinda rhymes, no?

Given Rick Pollack’s PLA printing success and temperatures at barrel entry rather than nozzle, I should probably start delineating between temperatures at the barrel and nozzle.  If barrel entry temperature is truly a critical factor, then he’s totally right about how going by nozzle temperature is like driving a bus with just the rear view mirrors.

However, this gives me pause.  Everything I’ve read about ABS suggests it may be best to melt it right at the nozzle as quickly as possible.  I’ve found that ABS cools very rapidly too.  PLA on the other hand takes a while to cool (but, then again, I was running my extruder too hot) – with the parts being quite flexible for some time after printing.  If barrel entry temperature is that important, then it seems that PLA must need a longer time to melt.  If this is the case, should the nichrome be wrapped higher on the barrel?  If so, then Rick’s heater cores (which already seem very convenient) are downright brilliant – since you can probably easily adjust where the heat is being applied.

From Nophead’s comment I gather that I was, indeed, running my extruder too hot.  I found that at my ABS temperatures (220+) made the PLA just drip right out of the heater – and once that had basically stop it would then intermittently release little amber droplets of plastic.  I must have been really cooking it.

With the limited printing I managed with PLA I found that it printed well with my non-temperature ABS Skeinforge settings.  So, before I go back to PLA I think I’ll finish tuning my ‘bot using Nick Ames’ Skeinforge tutorial.

Rebuilding my extruder

Posted on by

Over the weekend I rebuilt my extruder after some adventures with a blowtorch.

I used Rick’s single nichrome wrap method, which served me well on my last re-build.  The documentation of his method is absolutely fantastic and a must-read if you’re rebuilding your heater.  (That page is about PLA, but the nichrome wrapping is pretty universal).

I’m not sure if I wrapped my thermistor better or what, but I seem to be getting more consistent readings from it.  Perhaps this is due to RepG v12?  I would tend to think not since I’m using RepG v12 with the Zach 1 temperature table – the same table I was using before RepG v12.

How are you printing with PLA?

Posted on by

I’d like to print in PLA, I really would.  No warping?  No rafts?  Smells like syrup?  Makes kittens and rainbows?  Sign me up!

Rick from MakerGear has the following suggestions for printing in PLA:

  • Have a 150-160 C degree temperature for the entry of the barrel
  • He notes that the nozzle temperature is roughly 190 C degrees
  • However, later he suggests printing at 220-235 was possible
  • He suggests not to worry overmuch about PLA in the threads – its just one of those things

Nick McCoy offered several pieces of wisdom:

  • He found that 10W-30 oil added lightly to the PLA as it entered the extruder, by adding oil to a piece of cotton wrapped around the filament, helped it print without jamming
  • He noticed that pausing the extruder for more than a few seconds would jam the barrel
  • He found he could print at 180-210 degrees (I assume he’s measuring the nozzle temperature as you would with an ABS setup)

Nick’s results suggesting a nozzle temperature of 180-210 seem to match up with Rick’s findings of 190 or so.  I think I’ll give Polly another shot and see if I can extrude at those temperatures.

MakerBot extruder clog experiment

Posted on by
DO NOT USE THIS extruder unclogger setup

DO NOT USE THIS extruder unclogger setup

UPDATE: DO NOT USE TILES!!!  THEY WILL SHATTER!  READ LATEST POST!

The bad news is this is my first clogged extruder.  The good news is I have all the spare parts to whip up a new extruder, no problem.  That means I can experiment with wild abandon!  My backup plan is to slice and dice the PTFE insulator into washers.

Having drilled out most of the plastic clog from the barrel, it’s mostly empty.  The PTFE is in pretty good shape with the threads intact, if a little worse for wear.  My plan to get the remaining plastic out of the nozzle is to put the nozzle/barrel assembly into the large washer upside down and prop it up on some ceramic tiles.

My hope is that by applying a heat source to the nozzle the plastic will just drip/fall out.  The suggestion for using a blow torch to clear out the barrel and nozzle comes from Rick Pollack / MakerGear.  Thanks again Rick!

By the way, wicked Google Sketchup skillz, no?

Plastic oozing into threads – is that the end of my insulator?

Posted on by

I don’t know, but I’m about to find out.

I’ve managed to clear out the PTFE insulator pretty well.  I pulled the entire heater out of the extruder, turned up the heat a little, held the barrel lightly in plyers, and unscrewed the PTFE without a problem, and then turned the heat off.  I then used a precision flathead screwdriver to follow the threads, popping/chipping the plastic out as I followed I went.  However, I don’t know to what extent the threads are still intact.  Since the PLA oozed into the threads, I have to think they’re messed up to some extent.

As for the barrel, I used a drill bit with the unsharp end wrapped in a rubber band.  I rotated the bit using the rubber band as a grip to drill out the plastic.  It actually worked really well for clearing out the barrel right to where I can see the barrel entering the nozzle.  The inside is reasonably clean, but I still can’t put a filament into it freely.

I also had to take a precision screwdriver and follow along the threads on the barrel to chip out plastic.  This went reasonably quickly.  Once I was done the nut was able to screw on and off freely.

Now I’m left with a slightly discolored PTFE and a mostly clean barrel.  I’ve got a spare PTFE insulator, but I’m hoping this one is salvageable.  It still has threads and the barrel will screw in nicely.

Rick and Spacexula have suggested I use a torch to heat up the nozzle and let the plastic burn/fall out.  But, this is a trick for another day with proper safety equipment.

Oh, and before I forget, Spacexula suggested keeping a ruined PTFE barrier to slice into insulating washers.  I’m hoping I might be able to re-use the PTFE insulator, but this is certainly my backup plan.