Just a little. I completed the body assembly of my Thing-O-Matic, but not the MK5 Plastruder.
I just finished up the plastruder, so I’m going to bolt that in and move on to flashing the firmware.
Tag Archives: plastruder
It will be mine. Oh yes, it WILL be mine…
Want
MakerBot just announced their brand spanking new 3D printer – the Thing-O-Matic! As far as I can tell, the highlights are as follows:
- Automated Build Platform – version 2.0??? Guys, I just built my version 1.0 a few DAYS ago! Did you design a time machine to let you import new developments from the future?
- MK5 Plastruder – I’ve got a MK5 and I’m very very happy with it.
- Internal electronics like Charles Pax’ Muffin CNC. The wires sticking out all over on my ‘bot make it look extra DIY. Having all the electronics and wires inside certainly make the Thing-O-Matic appear more like a real honest-to-goodness appliance.
- Generation 4 electronics. I don’t know what in all this means – except that I can plug a standard USB cable into it rather than the funky cable I currently have and it will allow for some kind of automated printing. The Cupcake requires a fair amount of attention when you’re setting it to build something – getting the print head to the exact right height is something you just get used to. For all I know, there are other improvements with the Gen 4 boards – but I’m waiting to hear just like you guys. :)
- Higher resolution. I can’t wait for more details!!! From the announcement post, it appears that Z axis will move much faster – fast enough that the blobs that can occur between layers could be a thing of the past. These have never been a huge problem and I’ve gotten used to a little post-production finishing on my parts – but it would be great to not have to do nearly as much.
I’m wondering how the Thing-o-matic homes in on the correct start position? Does it do this with opto-endstops?
What do you want to know about the Thing-o-matic?
Plastruder MK5, now with 85% less heartache!
Of all the bits to get working on my MakerBot, the Plastruder MK4 was the most challenging. There were so many ways for some critical component of the Plastruder to go wrong. You could:
- Cut the wrong length or resistance of nichrome wire
- A small patch of nichrome fiberglass insulation is scratched off, creating a short
- The nichrome is not wound close enough to the barrel, requiring extra power to heat
- There’s too much space between the barrel and nozzle, creating a gap where plastic and build up and cause a blockage
- Heat can travel up the barrel and plastic can ooze up the threads
- Heat can travel up the barrel, plastic can pool and then cool causing a blockage, bulge the PTFE
- The thermistor can burn out or short out
- Heat can cause the thermistor or nichrome to become unsoldered or lose connectivity
From the description of the new Plastruder MK5, it sounds like the improved designs solve all of the above potential problems!
Update: Beak90 offered several other possibilities!
- one could not heat it up enough and strip the PTFE threads.
- one could heat it too much and cause the PTFE threads to fail.
- one could put the thermistor in the wrong place and have it read the wrong temp.
- one could wind the nichrome in 2 layers and have it not heat enough.
- one could tighten the nut on the barrel too much and cause extra stress on the PTFE causing it too fail.
- one could forget to say the required magical incantations before firing up the plastruder causing everything to fail.
And, one more I just thought of:
- Fail to play Daft Punk
MakerBot haiku
Clear PLA sits
Mendel languishes alone
Plastruder hates corn
It’s not just me!
See! Spacexula has discovered the hard way she’s a wicked temperamental woman!
Shattered acrylic plastruder… Yikes! I printed up one of Zaggo’s Prinstruders – but it appears to be optimized for an early MakerBot Batch 5 with large/small dinos. If I wanted to use my printstruder I would need to pick up some of the extra parts required and essentially print up a small dino.1 However, I think I’d like to start replacing parts out of my MakerBot with printed parts so that I can keep the originals as backups. However, I have a feeling a prinstruder out of ABS is going to be much more robust/resilient than the layered acrylic plastruder. What do I need?
- 2x 626 ball bearings.
- 4x M4 bolts, 60mm long
- 4x M4 nuts (optionally two of them as wingnuts)
- 1x M6 bolt (30mm long)
- 1x M6 nut
- 3x M3 bolts (30mm long)
- 3x+ M6 washers
- 3x+M3 washers
- 4x M4 washers
In addition to these parts, I’ll also need to measure my ‘bot for a small dino equivalent. Since my extruder barrel is out of commission and the plastruder is just lying on the platform, this is as good a time as any to measure it up.
- Shopping list below [↩]
My first hack
Seeing as how I already had the heater in pieces, I figured it couldn’t really cause that much harm to move the plastruder board. I totally get why the MakerBot guys put the board on the extruder – that way all you had to do was swap out an extruder and you can roll with a totally new print head.
I don’t really intend to do printing beyond single color plastic. This may very well change if we see a support material extruder being offered. But for the foreseeable future, I am really looking forward to printing away with my giant coil of black ABS.
That said, I’m not attached to the idea of having totally modular heads. 1 On the right side of the MakerBot there’s a really large area above the motherboard and to the left of the three stepper motor boards. The only things preventing the plastruder board from being mounted right there are (1) the motor wires are too short and (2) four holes in the body.
I had dissected a piece of ethernet cable for the wires running to the nichrome wire and thermistor, so I still had four wires left. I used another two and a bit of solder to extend the wires to the extruder motor.
Sometimes when I need to drill a small hole through soft or thin material I don’t even bother with the drill. I used a small drill bit with a rubber band wrapped around the non-drill-bitty-end to give it a grip and rotated it into the right panel of my MakerBot. Bolt it on and…
Presto! Now I can see all the way through the plastruder. :)
- Sorry about the pun. [↩]
With a little help from my friends
Thanks to the kind folks at the MakerBot Operators Group I’ve been diagnosing what’s going on with my Y axis stepper board and plastruder.
1. Y Axis Stepper Board
No matter what I was doing I couldn’t get the Y axis stepper board to respond to any commands. Also, the power light on the board would light up as the MakerBot powered on – however it would immediately dim to nothing. I swapped out every single cable, the motor, and it was always the Y axis board! Finally, I completely pulled the board off the ‘bot, pulled every cable, and started adding the cables back one by one… and it worked!
I was concerned with why it wasn’t working, but happy it was working. So, I bolted it back on, connected the wires… and it didn’t work any more! What went wrong? It was one of the opto-endstop cables. I discovered that when I connected the front opto-endstop cable it would kill the power to the Y-axis board – or any other board!
The Y-axis three prong cable is easy to insert upside down. And that’s what I was doing – because it fit better in that orientation. Well, flip it upside down and rock on!
2. Plastruder / Extruder Temperature 0.0
Now that I could manipulate the 3 axes, I tried to use the plastruder. I noticed that even at room temperature the thermistor was reading 0.0. Also, the heater was smoking a little, I could smell something burning faintly, and the extruder was oozing something clear and sticky. Not ideal.
With a lot of help from the guys at the MakerBot Operators Group I attempted to diagnose the problem. Here’s what I tried:
- Testing the resistance of both the nichrome and thermistor while both were still plugged into the plastruder board. Both seemed okay – but I still could not get a reading from the thermistor.
- One suggestion was to plug a random resistor into the thermistor ports to see whether the board and software was receiving information. Being a complete novice and having zero spare parts around, I actually had to make a trip to the local electronics store for a single resistor. 1 Once plugged in the resistor (a quarter watt 10k) must have been resisting stuff because the board interpreted it as a temperature. Thus, the board and software are probably fine. 2
- Thus, I disconnected the heater wires and thermistor wires and tested them away from the board. I really should have done this in the first place. It would have told me that the thermistor was either burned out or no longer connected to the wires.
- Taking the heater apart was almost painful. The ceramic tape was a little scorched, parts of the kapton tape closest to the print head were actually burned to a blackened crisp and flaking off. It was just not pretty.
- The nichrome seemed to still be intact and giving the proper resistance, but the thermistor was not showing connectivity. I was pretty bummed that I may have cooked it. But, when I started to peel that tape away, I tried to test the resistor leads – which did show the proper resistance! I checked the connections between the thermistor leads and the solder and discovered that one of the leads had lost its connection with the solder/wire.
- I then tried to resolder the wire to the thermistor and then rewrap it into the kapton tape and tried its resistance again – and got a proper reading. Then I taped it to the extruder head, to see if I could get a heat reading off of it – and I did!
- This time, I went VERY slowly. I tested the heater/extruder head completely apart from the printing assembly with the thermistor taped to it – I could heat and read the temperature. I then wrapped it in tape, tried again, success again. Then I wrapped it back in the ceramic tape, heated/read again with success. Then I put the assembly back on the plastruder, heated/read again.
- Now, a decision I made that I may very well regret later was to leave the nichrome wrapped as it was and not pull it all off and rewrap it. The testing showed it was intact, it was still in its fiberglass insulation, and I had done a pretty good job of wrapping it in the first place. In rewrapping the heater I took out as much of the burned kapton tape as I could and then wrapped it back up.
- I picked up a lot of other stuff while there, but this a single resistor was the actual purpose for the trip. [↩]
- Thanks Rick Pollack! [↩]
Plastruder Mark IV completed
Just finished the Plastruder Mark IV. The most difficult part was soldering the leads to the thermistor. It’s so tiny! I didn’t notice any unusual tricks to getting it completed or anything that wasn’t in the directions.
MakerBot Build Status
The body is painted, bolted together, rods have been cleaned, XY stage installed, boards soldered and bolted on, cables run.1 I’ve affixed the opto-endstop triggers on the X and Y axes.
- I have not installed the Z axis endstops mostly because I’m just not that keen on marring that beautiful clear acrylic sheet that is the Z stage. I’ve created a little fitting out of balsa wood that will eventually support the opto-endstop triggers.
- I’ve assembled the two “dinos” but not any other parts of the plastruder.
- I need to assemble the rest of the plastruder, drop it in, and fire it up!
- Even if the opto-endstops are going to the wrong max/min ports for the moment. [↩]
Stopping for now
The body of the MakerBot is complete, rods in, X and Y stages in, pulleys and belts on, motors bolted on. No opto-ends stops yet for obvious reasons. The opto-endstops also require popsicle sticks.
On to the plastruder. I put together the Weird Dino and the Tall Dino, but the idler pulley requires super glue. I don’t happen to have any lying around, so I’ll need to go out to the hardware store. But, this is as good a spot to stop as any.
I originally intended to document each step – but the directions on the MakerBot wiki are so good that there’s just no need. So, the pictures you’re going to see are going to basically jump from a bunch of spraypainted wood giant chunks of the robot already bolted together.
The build process, much of what consists of fitting pieces together and using the MakerBot “t-slot” semi-captive nut method, is very intuitive, relatively easy, and extremely gratifying. Sometimes its a little bit of effort to get that nut in the notch properly, but it was never that bad.