Key Our Cars What are you going to do next?!


Print Spares!

Posted by Dennis

Fairly imporant, in my opinion, tip.  If you have a printer that has printed parts.  Print spares.  Of everything.

Of course breaking a part may lead you to make something better if you have the stuff to do it but still have spares.

Case in point, my Z axis end stop broke.  It's hard to zero a printer when the thing that tells it when to stop is broken.   I tried gluing back it together, no go.  I tried heating and smushing backing together.  No go.

Well crap.

But I had some 1/8" by 1/2" bar stock so bent one end at 90 degree angle of about the right length.  I then cut it off at the right overall length.

I drilled and tapped a m5x8 hole in the short section and two 1/4" holes in the long section that matched up with the pieces of the printed part.

A little grinding on a bench grinder to put the necessary screw relief in place and I'm back in business.

I'm printing a couple of spares now but I don't know yet if I'll leave the steel one in place or swap it out with a printed one.

I'm also printing them with 3 shells, layers and 50% infill in PETG.  The original seems to have been 2 and 10% and in ABS.   Not the strongest print in the world.

Anyway, if there are breakable parts on your printer then have spares.  It'll save you some grief.


3D Eez

Posted by Dennis

As a recent member of the 3D Printer owner's club I was having inconsistencies with first layer adhesion.   My very first print, a calibration box, printed okay on plain glass but I then looked at other options for PLA printing.

My first try was the basic purple glue stick from Elmer's.  I had inconsistent results.  Sometimes a print would be okay, sometimes not so much.

So I tried a mix of white glue and water.  But apparently the 'washable edible' version of Elmer's glue is not the right kind.  I had zero luck with that mix.   So I found the old school Elmer's and had better luck with that but printing things like Darth Vader with Cape even with some brims had issues.

So I jumped on the IRC forums that the guys from MakersToolWorks pretty much live on and we got to talking and they recommended 3D Eez.  It's on the pricey side but some other internet research, not a lot of sources though, indicated it was good so I ordered some.

It's supposed to be good for non-heated beds but personally I think it would work better for heated beds just based on the difference in holding power between a hot and cool bed that I've seen first hand.

I followed the directions and applied three thin coats letting each one dry, go transparent, before applying the next one and alternating the direction of the coats.

And the results were pretty amazing.  At heated bed temps the smallest objects stuck so hard it is pretty much impossible to remove them from the bed.  Even small surface area pieces act like they've been epoxied to the bed.

Then when the bed cools down, drops below 28C (ish) degrees the pieces pop off with just a light tap or pry from a spatula.

The material does 'wear' out over time but it does not appear to have anything to do with the number of prints but the amount of time it is heated.   I say this because the entire surface faded out on me after about 3/4 of a roll of filament's worth of printing.   Whether it was in the center of the bed where most of the prints were or out on the edges, it didn't seem to matter, it went from great adhesion to really bad adhesion and my skirt was just getting dragged around by the nozzle and not sticking at all.

You can run a damp cloth over the surface and get it back to sticking again but from personal experience it didn't get it back to the 'day one' ability to stick.

The material comes off pretty easily under running water water with a paint scraper so clean up isn't a big deal.

Applying it again and everything is back great for first layer adhesion.



MendleMax 3 after a couple of weeks…

Posted by Dennis

20160115_150448I've now had my MendleMax 3 from MakersToolWorks for about 3 weeks now.  By 3 weeks I mean from my first print till now after going through the build process.     I've gone through roughly 2 rolls of PLA filament, also from MakersToolWorks.

During this time I've run into more than a few issues but they've all been the result of my not knowing what I'm doing.   The printer itself has been rock solid the entire time.

Note several of the objects on this page were printed while I had a partial clog of my extruder nozzle without realizing it and was fighting with under extrusion of material.   Also if you can't see any images in this article then check AdblockPlus.  It's blocking them for me for some reason in Firefox.   I assume because my image location matches some filter.

So let me run through the issues and maybe they might help you avoid similar problems.20160115_150244

  1.  Don't pull on the filament while the extruder is at temperature.  It seems obvious right?  In hindsight yeah, as soon as I did it I just closed my eyes knowing what I'd just done.  I'd just pulled molten plastic up out of the nozzle and into the rest of the extruder where it's not supposed to be because hey that part stays cool.  And as you might have guessed the plastic solidified and I had a big jam.  And not the good kind made out of strawberries.  But since I, and you if you buy one, put that extruder together I knew how to take it apart.   It was fairly easy to clean up, the E3Dv6 that is in the MendelMax 3 is from what I hear a very nice design and one that helps stupid users get unstupid.
  2. Print out a filament guide sooner rather than later.  Indeed you may want to do that as your first print.   Without a guide it's possible for the filament to unspool and then get kinda tangled up and then things go downhill after that.
  3. When you put the extruder together, while you should take some care tightening the nozzle down against the heat break, don't be afraid of it.  If you are then you won't tighten it enough and it may (read did) ooze plastic out the joint several prints later.   Liquids, even viscous liquids like molten plastic, under pressure will find any opening.    So extruder taken apart a second time.20160115_150049
  4. When you take the nozzle apart, make sure you get it cleaned, especially if you used heat to get the plastic out because you might just carbonize part of the plastic and leave a partial clog in the nozzle.  It 'seems' to be printing okay but now you're under extruding.  And if you try to increase the steps in the firmware you run into back pressure issues that will cause your extruder to skip.
  5. If you try to use a pick to clean a nozzle, then make sure you've already bought your replacements because friends unless you have a pick that's exactly the size of that nozzle hole, if you've heated the nozzle up then you've softened that brass and voila now you have a .6 or even bigger nozzle when you started with a .4.
  6. Make sure you put a filament cleaner on your filament.  This could be something cool you printed from Thingiverse or just a piece of foam with a slit in it you stick on the filament.  Especially if you're unfortunate enough to own a cat.  Cat hair taking a ride on your filament into your hot end may be a bad thing.
  7. 20160115_150202Skip the PVA (white Elmer's glue but NOT the washable kind, the old school kind) and water mixture,  skip the purple glue stick, skip the big ass roll of blue tape.  Go straight to 3DEez as your bed wash.  PLA at least sticks like a frickin' magnet to this stuff while it's hot, I mean jerk the printer around as you try to yank them off kind of strong, but as soon as the temp's drop to 28C or less they pop off with just a light tap.   I've done probably 15+ prints with my first coating (3 coats per the instructions) and it shows no signs of wearing out.
  8. Rafts suck for leaving the bottom of your prints texturally sucktastic.   But if you follow #7 you won't need rafts.  You may need brims for very tiny parts but you shouldn't ever need to do a raft again in my admittedly limited experience.20160115_150049
  9. If you run into any issues go to the IRC channel.   Let me repeat that, if you have any questions or issues, go to the IRC channel.  The MTW guys in my experience are super knowledgeable about their products, they all use their products and they've 'been there done that' when it comes to settings, tweaks and issues.   And they seem to be pretty nice folks.  And I'm not saying that just because they're in the same state I'm in because one of them is Canadian and well.... yeah... 🙂
  10. Be VERY careful if you start screwing around with sending GCode to the printer.  If you don't for example change from relative to absolute movement you can send things way off of where they're supposed to be.   In my case I wanted at the end of the print for the Z axis to raise up 2mm, the X to move to the left and the Y, aka the plate, to come all the way forward.   I figured out my error as the plate just didn't want to stop and yet another mad slam on the emergency stop button I'd wired up on the power strip I was using for the printer.
  11. Make damn sure your slicer software is reading your thermistors before you send a heat command.  I managed to not do that once, it only happened the once so it was some kind of fluke but it was reading room temps on the thermistors and I noticed when I started smelling plastic that was at way too high temperature and smoke was starting to come from my extruder head.  I don't know how hot it got cause I hit my emergency power off switch but I'm sure it was well above where it should have been given the smoke.
  12. Many, maybe a lot of, printable models posted on the various sites are not in great shape to be printed.  Many have have been ripped from some software (i.e. a game) or something similar.  They suffer from non-manifold surfaces i.e. they have holes in them or just very hard to impossible to print shapes without a ton of support structures and the like.   Or their default orientation may be bad for printing.  So don't expect every print to work and it might have nothing to do with your printer but rather the object you're trying to print.
  13. Be careful with your heat spreader if you're screwing around with your printer.  I managed to yank one of the leads off my heating pad and was wondering why my bed wasn't heating anymore.   A little solder and it was good as new.
  14. Buy some basic spare parts.  A spare nozzle, a thermistor, extruder head heating element, these seem like a very good thing to have around since if you screw them up you're down until you get replacements and they all seem kind of consumable and are stupidly cheap to buy now.
  15. An enclosure of some kind can make being int he same room a little better if it's a room you watch TV in or something like that.  The printer is not noisy per se but having it 5 feet from your head it will compete a little with the sound of a show or music etc.

20160115_150516Final thoughts -

In my last few weeks with the printer, I've only printed PLA and honestly my first results using the default settings were good but over the last few weeks I've learned to dial things in.   Increase retraction a tiny smidge, play with speeds and cooling and everything.

After my first spool using MatterControl, the software offered for free and with custom profiles specifically for the MM3 by MTW, I didn't like some of the tool paths, they seemed less than optimal.  I would catch myself watching the prints and going "What?  Why are you going way over there?  You should go to that one it's closer and on the way!"

I do have some experience with CNC machining although in metal and paths and such.    Additionally I found myself wishing I could manually put some supports in just a couple of places given the ability of the printer to print overhangs and inclines so well.   So I bit the fiscal bullet and picked up a copy of Simplify3D.  This is not a cheap purchase and honestly for most people MatterControl is more than sufficient.

But with Simplify3D you can have easy per slice control of heat, cooling etc, you can manually place just the minimum support structures you need and in the end I decided it was worth it.  I honestly think if the makers of S3D would drop the price to say $49.95 they'd sell far more than 3 times the number and end up with a more significant profit margin.  Valve has proven that beyond my satisfaction that selling games at the 25-33% cost they sell FAR more volume than they need to make up the difference in per unit pricing.  But anyway, the tool paths that S3D uses are indeed more optimal than MC's with less total traversal and can reduce your time to print by some small percentage.  At some point I may test that claim by printing a semi-complex print that takes long enough to give useful data.   In the end it's up to you and your wallet to determine if it's really worth it and for most people it very well may not be given the high quality of the software that MTW is providing for free.

20160115_150359Since I printed my first calibration cube I've printed a butt ton of things, most of them of no real use except as gifts.   Some sets of figures for a game called Pocket Tactics and again the quality of the printer is great.

<- This for instance is a little feature test I created in Max for the fun of it.  There are some other parts to it that are missing, you can see where they were broken off but it was a series of thin verticals about 15mm high that went from 90 to a 30 degree slope.  But the way I joined them to the plate in the 3d application left them weak and when subjected to a kids curious fingers they ended up broken off.  Watching it create something in mid air for those long bridges is pretty cool.

I did have an interesting screw up, I set my speed to 80mm/s to test print a whistle at high speeds.  But I forgot that I'd set the override control in S3D to 130% movement rate which if my calcs are right puts me at 103mm/s print rate.   And other than a few clumps on the outside it actually printed.   Sadly the whistle doesn't work that well.  It's certainly not the 118db that is posted by the designer but I did print it at mach 5 so to be fair I should try printing it at a more realistic speed.

In a side tangent, if I had a miniatures based company then 3D printers would be a concern of mine.  Granted you need someone with enough skills to create 3D figures but there are plenty of skilled folks on the internet doing that kind of thing for free.

Right now I'm waiting for my replacement nozzle to come in, the one I broke,  and after so much constant "Vrrrrrrr" noises my office seems extra quiet.  But I should have it tomorrow in time for the long weekend and we'll be trying some PETG maybe.  Or at the very least finish printing out the dice tray I designed.   Once a geek always a geek.