MakerBot Industries

Well, maybe…. I did try to get the damaged board running a bunch of times after re-soldering. I doubt anything was damaged, because I think it is reporting the right temperature. At room temperature it reports 24 C… which is correct. And really the heater pins were never really messed with… but maybe I should check if it is getting the proper voltage. It sucks because I did a whole bunch of things at once…. I added the aluminum build platform, I broke the heater board, I switched to Ubuntu, I tried to repair the heater board several times. Introducing so many variables makes it hard to troubleshoot in a scientific way.

I guess it doesn't much matter… ABS seems to be sticking fine… and I have decreased temp to 100 on the heated build surface. Maybe it just needs to be broken in a little? (doubt it).

Just tested my HBP I set the temp to 130 and it did indeed reach that temp. After it got to about 110 it did slow down though.

Something new I encountered was a warning about setting it past 130. Must be a RepG 25 thing? Or maybe I just never noticed it before. Iv never really run the bed this high.

Do your boards physically look the same? Are the surface mount components all the same?

No,the temp warning has been around since version 24.

As to the board not reaching full temp, it can only be 2 things, resistance is greater, or the thermal mass of the new aluminum plate has your PID settings off. It's likely the latter, although I just noticed on my tall T-O-M the heater ground pin on the HBP board had gotten hot enough to turn the connector yellow only on that pin— meaning it had too high of contact resistance and thus, the connector got hot. I just polished the pin clean and checked the connector too. Not sure why that happened, but I have been printing for like 150 hours non-stop on that machine. I'm getting paid big money for some mass production of parts, so it has been running day and night for weeks straight.

My PID settings have been the ones listed in the wiki. These also seem to be the new defaults. I have noticed no difference since switching to the new alu plate =/

Components… looked exactly the same as far as I could tell. Also, it still has heater board v1.1 written on it… so I think they are pretty much identical. Judging by touch, the surface of aluminum seems hotter than my old glass platform at 125 C…. but this could all be in my head, it's just I remember with the glass I was using, I could touch the surface at temperature… and hold my finger there for a second… with this Aluminum plate at 100 degrees, I have to pull my finger away immediately it seems.

I guess I can play with my PID settings a little. I noticed that there is a difference between this board and the old board by about 3 degrees off base temperature.

As for higher resistance… could this be maybe caused by bad solder joints? This one doesn't look as nicely soldered as the original.

Ok, we are crossing things up. My impression was that the new heater board was not physically reaching the correct temps. This can only be 1 of 2 things in that they changed the thickness of the copper layer on the PCB, which going thinner makes higher resistance or less wattage and heat —given a 12 volt source, or your contacts in the cable connector for the heater power started to go bad like mine did.

What you are now implying is that you have a sensing error which is a whole different issue altogether. This is possible due to known tollerance in the components used for the temperature sensor system. The good news is that you could calibrate that out, given a non-contact thermometer (mainly for speed of update) and tuning the base temp factor in the toolhead preferences. Back in the early Cupcake days, I got mine within 2 degrees of actual.

Here is the guide. http://wiki.makerbot.com/adjusting-the-thermistor-settings
I got my non-contact thermometer for $9 from Harbor Freight. YMMV

I got that same one from Harbor freight…

There are new developments. It is not a sensing issue.. because the contactless thermometer reads about 99.4 C when I have the heater board set to 100 C. I can now get my board up to 130 degrees, but it takes a very long time. I remember with the old board, often times it would jump 2 degrees at once (on gen 4 interface, where it polls for temp every 1 or 2 seconds or however it does). Now, I can wait two seconds and it won't climb a degree when it gets to the higher temp end of the temp range. Also, when starting from room temp, I find myself waiting for the heater board to reach temperature, instead of the extruder to reach temperature for the build to start. (meaning, the extruder makes it to 220C well before the heater board makes it to 100, and by ALOT!).

I have modified PID settings and the speed seemed to increase a little, but once it reaches 80 or 90 C, it starts to really slow down. If I want it to get to 130, it takes a good 15 minutes total. I used to reach it in 3 minutes or so (from room temperature to build I had timed myself at 4 minutes with the old board and an mk6+).

I was surprised changing the PID did anything though… because, you would think that the heater would be full on no matter what the setting was until it reached close to full temperature… Is this not a correct assumption?

I can now get my board up to 130 degrees, but it takes a very long time.

Sounds a lot like an extruder with one dead resistor… [grin]

That's closer to the truth than we might like. I'm using a pair of aluminum plates clamped together atop the same heater platform, so I have a somewhat heavier setup than you do. It takes quite a while to heat up, but still less than my homebrew (and also considerably overweight) cartridge heater extruder.

You can probably get slightly better results by turning the PID algorithm into a simple bang-bang thermostat. Set P=100, I=0, D=0 so that it turns on solid when the temperature is low and turns off when it's high, with no fancy PWM in between. The thermal mass of the aluminum plate will keep the surface temperature nearly constant, even as the heater varies slightly.

I haven't tried that, but it works fine for my extruder.

The problem is that the platform heater was designed to heat some aluminum foil and maybe a plastic belt, but now it's called upon to heat that big plate. Heating more mass with the same power means more time to reach a given temperature.

I'm just not even going to think about cartridge heaters in this context…

Renosis, yes, it is incorrect to assume the heater is full on. This is what the PID and PWM function of the current firmware is doing. You can easily see this by watching the LEDs next to the MOSFETS get dimmer as you come closer to set temp. Adjusting PID can help this. In theory, the "I" or Integeration function is supposed to do this. I'm actually in an industrial controls class speaking on this subject now. Integration means the the longer your actual temperature is different than set temp, the more "on" the heater is supposed to be. The Proportional function is somewhat opposite in that the further away you are from the set temp, the more "on" or "off" the heater would be. The differential function is mainly to dampen the swings near set temp.
This isn't like your oven where the heater is either on or off with a simple thermstat and a relay. This is why it's not behaving like you think it would.

@Ed OK, I'll try that…. Ya, before I installed the Aluminum plate I was using a glass surface covered in kapton (just because I couldn't think of a much better material than glass that would maintain a nice flat shape even when heated). So, my old heater board (the now broken one) probably had a similar amount of work to do in order to keep the glass heated. I do fully understand that adding more stuff (such as aluminum plates and glass plates) is going to cause the platform to reach operating temperature more slowly. But it should still probably beat the Heater Core to reach operating temp…. not take triple the amount of time.

@Jetguy I see. See I didn't realize that there was control of how much power was reaching the heater too (PWM). I thought the PID was basically only controlling the timing of when the heater is full on and full off. Well, you've made it much clearer now… thanks! :]

Ok, so I am going to check connections again, maybe try some different cables. Change PID to 100, 0, 0, see how long it takes. Maybe get a new board too?

Maybe get a new board too?

While you're poking around in there, measure the DC resistance of both heaters at the connector pins: unplug the cable and find out what's going on in there!

It would also be informative to measure the voltage across the heater pins in the connector while it's heating. It should be slightly less than the actual +12 V supply voltage measured on a Molex connector that isn't passing much current. If it's much less, like 10 V, then that suggests there's a problem inside the cable: perhaps broken strands in a wire.

Ed's idea may be the most likely with a failing wire, but you went completely wrong on what I was saying for PID. P= proportional. You have problems when the target temp and the sensor temp are somewhat close. Using 100 for that is way, way wrong. All proportional does is act as a multiplier based on the difference between target and actual temp. So, when the HBP is at like 60C and you set 120C the PWM is full on because the difference (AKA error) is large. As the board heats up, the two get closer together and tends to turn the PWM down and when the temps are very close to finally off. Integration or the I is the one you wanted to increase. SO again, you are at 60C and trying to reach 120 which takes time. When you increase I, for every second that goes by and you are not at 120C this raises the PWM power until max. This is more like the "Bang Bang" control from a relay (you are expecting) D should always be pretty low (way less than 1). D basically ends up being an opposite to the other two functions causing them not to "hunt" around the target temp. Typically we were running with very low I, but I is the one that makes it go either full on, or full off.

Go ahead and stay at 5-7 for P, but raise I to like 1.0 and lower D (possibly to zero).

Ok sounds good…

I only said P 100 I 0 D 0, because that is what Ed suggested to turn it into a "bang bang thermostat". I've read that PID control page that the Thing-O-Matic Further Calibration page points too, I think it was the first week I had my Thing-O-Matic… and I think I was more confused afterward than I was before I read it.

Ok, well I haven't tried anything yet, because I am in the middle of printing a project. But I shall try the settings you suggest.

Also, I kinda jumped the gun and what Ed told you work too. It's just a different way of looking at it. Increasing P is increasing "gain" on a typical servo or feedback loop control. Maxing gain will slam the output to the "rail" too. My thoughts were that since we have a huge time constant, gain was not the area of interest, but rather I because that is the time constant based portion of the function. Even only slightly increasing I has a huge effect on the output (AKA it's very sensitive).

Ah, no worries. Hey, your gen 4 mendel looks pretty sweet.

Ooh I want to see!

http://www.thingiverse.com/derivative:9623

That is where I saw Jetguy's setup…. got any more pics?

I don't want to derail your thread but I wonder how much had to be changed in the machine xml to make it work with gen4 MB electronics.

The only changes was to copy the z axis info from Cupcake since I'm using the same 8mm allthread for Z on a direct drive pulley (again, stolen from Cupcake whe I upgraded to a z-rider) and then make the X, Y and Z axis match the actual build area (185mm X 210mm X 101mm). Since I used Pololu 1/16th step driver for X and Y but Z and A (MK6) are on 1/8 MBI drivers. So you simply double the steps per MM number on X and Y.

Again, if you just used a complete gen 4 set, you would have all 1/8th drivers and the only major change is the Z axis.

<axis id="z" length="101" maxfeedrate="240" stepspermm="1280" endstops="max"/>

Basically, let's say you put gen4 on a cupcake, then the exact same mod is made to Z!! It becomes a T-O-M. The only other "fix" is that the homing command stops after a certain time before it reaches the endstop-so the fix is to modify the start.gcode in your profile to have the homing command more than once (2 times did it for me) YMMV.

(**** begin homing ****)
G162 Z F1400 (home Z axis maximum)
G162 Z F1400 (home Z axis maximum)

Ahhh sweet thanks! That's actually what I was looking to do with the Mendel keep it simple and use what I have experience with from the TOM. Think I will print the rest of the Mendel (I had only printed 3 parts) after all, funny how these machines start to multiply once you get one I'm gonna end up with 4.

So this even freaks me out. Right now I have 2 T-O-ms, a Cupcake upgraded to gen4, MK6+ and the lowrider and z-rider, plus HBP (so basically a mini T-O-M), my RepRap on Gen4 and MK6+. This week, Ultimachine is shipping another Mendel hardware kit for which I have all the parts(right now, that will be Ramps based), then Makergear is shipping me a Prusa kit complete (also RAMPS), and then the KING of all bots, an Ultimaker is being shipped and will be upgraded using the RepRap heated bed (from Ultimachine). The bot farm just got real big real fast. Due to some recent prototype work- the machines are paying for themselves!! This means I will have 4 bots that can print up to ~ 210 X210 MM and 2 more that do 120 X120, and one of those can do 170+ height builds, then the lonely Cupcake that still does the best prints for smaller objects.
All 7 bots have stepper extruders (5 of them are MK6+).

I'd say this is going to be hard to beat for print capability. The Tall T-O-M is the "pretty" bot, but evrything else is about big build area and using the same profiles across the fleet making life a lot easier. The only change is build height, and that is about to get fixed in Replicator-G version 25 according to rumors (Z height in firmware where it should be).

My MakerGear Prusa comes soon!

It only took me 5 months from my first printer to get a second!

I was actually toying with the idea after the first 3 weeks though! :]

Oh, I just re-did all the connections for the heater platform. I also did a P= 100 i = 0 d = 0…. it now almost reaches temperature as fast the extruder. Which I can live with.

Sad thing is, I re-did the connections at the same time as I set the PID… so I have no idea which thing was responsible for the increased performance… stupid huh?

I also fixed a problem I was having with my X axis being ALWAYS on…. meaning, even with steppers disabled, it was still getting "holding" voltage. I swapped my pololu's between carrier boards… the problem did not move to the other axis. So I knew the problem was with the X carrier board. All the solder joints looked really good. But I did a reflow(is this the correct word? Meaning, I reheated each joint with the iron.) on each of them. And problem solved!

I also extended the length of my cd-rom style cables, for the endstops and e-stop.

Today was major maintenance day and my bot is running so smooth now.

Thanks, for the help!

As always, just glad to know you are printing again! It's like the whole community is sad when we know somebody has a sick bot.

What I keep bugging MBI about is that isn't this what Robot Hospital is supposed to be about? Fixing Bots!! Honestly, I got made to be the A~~~ole over that whole thing.

Jet are you one of the two green blips on the Ultimaker map that has a shipped bot? I'm wondering what batch mine is in, I remember Dave mentioning the other day he was expecting it when he got home.

I agree about RH it should be geared more around tuning and fixing your bot to get up and running faster.

I just wish they would increase the length some more. It used to go sometimes 30 minutes. Now we are lucky to get 3.

They may not want to discuss broken bots too much, because it isn't good business sense. No matter how much it would benefit everyone and how much I would prefer more tips like this. I mean, whenever a robot hospital episode comes out, it is right there on the front page. If someone is considering buying a bot and they click the link and see that they are telling you how repair your broken stuff… then they start watching more episodes and it is more "broken bot" talk. They may get the wrong idea.

It might be kind of like people coming here to the forums. I mean, if you looked at these forums every day, you would probably get it in your head that MakerBots break all the time.. no matter how untrue it is. If you are told something enough times, you start to believe it.

And I know, the name of the show is "Robot Hospital"… which makes one think it should be about broken robots. I would actually like it if they talked about mods and hacks too.

Yeah that does make sense, maybe not as much about fixing bots but rather getting better quality prints would be great.

The axis offsets have been moved in the new repg25 RC

Definitely much nicer then digging through the file structure.

I have no idea why the X and Y offsets go down to that ridiculous of a value.

I had originally put in -57.5 and -60 after calibrating my X and Y build area but for some reason it turns out to what you see. Maybe a bug in RC who knows.

RepG 25 is out? I had no idea!

Wait a minute? Is that a centralized place to set Z height and x and y offset? That should have been there ages ago! That is awesome!

Thanks!

Ya robot hospital SHOULD most definitely have more tips for improving print quality. And like I said, I think they SHOULD do tips about bot repair… Just I don't think they are going to, because of the reason I listed earlier. Definitely need to go back to the longer episodes for sure!

Related back to the original thread, my tall T-O-M decided to catch the HBP cable and break the ground wire on the thermistor circuit. The build completed but I didn't discover the issue till I told it to print again. I'm printing from SD and using the LCD Interface module so I was like why isn't this thing building in my middle of the night stupor. Then I saw the HBP wouldn't rise, stuck at 24. TIP-O-The-Day, 24 is really 1024 since the LCD control panel is limited to 3 decimal places!!! Duh. Classic 1024 thermistor circuit open, but not nearly as obvious if just using the LCD interface. 24C is a valid temperature for the HBP that still has a warm object on it.

I'm sure somebody else will get caught by this one too.

Simple fix with the soldering iron, but it's all about the trouble shooting to identify it. Especially when it's not plugged into a PC.

@Jetguy, LOL, I was thinking during troubleshooting my broken heater board "Why the heck is it reporting the correct temperature on the Interface and not the control panel?"

I was also wondering why it wasn't raising either when I started a print. I was actually caught by that one…

And it will happen to others… maybe they should increase the decimal places to 4… or add some kind of "if HBP temp = 1024, then print 'ERROR!'"

That interface firmware needs A LOT of work!