LaserCut Mendel by Tech Zone Remix

If I understand you correctly, you're able to communicate with the MB and you were able to upload the 5D firmware to it. But, did you also load the Extruder firmware to the extruder controller? To do that, you have to plug the USB-serial adapter directly to the extruder controller after disconnecting or turning the power to it off. Also, you have to select Arduino Diecimilla... in the board menu. BTW, that was the firmware that I modified. I don't think I made any modifications to the 5D aside from the configuration.h file in this one.

Yeah I was able to load both the firmwares, each to their respective boards. Flashing the extruder had been working flawlessly, had just been having issues with flashing the MB. I sorta figured that the MB firmware wouldn't have changed much but I figured I should get everything to a known state to start with.

At this point, my understanding is that the MB is not getting a value for the extruder temp and is therefor returning 2000. I am able to get the extruder motor to turn from the reprap host software so I assume that means the communication between the MB and the extruder is good, please correct me if that is not correct. If the extruder firmware is correct then the issue would most likely be with the A-D or possibly the thermocouple. I will re-flash the extruder to be absolutely sure the firmware is correct on the extruder. This time I will have the verbose setting enabled so I can see what it is actually doing.

I am curious though what the "B:0" or "B:2" in "...temperature reading: T:2000 B:0..." lines from the reprap host software mean.

PS I had put 2 and two together to figure out that you were the one who had added the A-D code.

The extruder motor is controlled through two separate digital lines (D9 and D10) to the motherboard for direction and step. It's not done through the RS485 connection between the two boards which is how the temperature is set and read: M104 or M109 to set the extruder temperature, M140 to set the bed temperature, and M105 to read both temperatures. It's also how the PWM for the motor control is set (M113). The T and B in the response to M105 refer to the Tip and the Bed temperature.

If your extruder controller is powered off, or it's not connected by RS485, then the MB will return 0 for both the tip and the bed temperature. If your extruder controller is properly connected, but the A-D is not, the firmware on the extruder will return a temperature of 2000. This is so that you don't overheat the tip. Since you're getting 2000, you must have connected the MB and EC properly and also you must have the firmware loaded properly. Your problem must be the A-D connection. You should double check that you connected the AD properly, There are 3 pins that it must connect to in the extruder controller. Check the picture in the techzone wiki carefully and make sure that you wired it correctly. They use the SDA, Gnd and 5V pins in the I2C in the extruder controller near the thermistor pins (labeled temperature). Also, make sure the thermocouple is properly connected to the pins near the surface mount chip.

The firmware code was from Techzone. I needed to use it with a heated bed and their version didn't support a heated bed. So I took their code and added it to the 20100719 version which supports a heated bed.

Question on Electronics,

I plugged in my Mendel (TechZone Gen 3 electronics) and the stepper controller lights each flashed 3 times in unison and then I lost all power. The motherboard lights still flash as normal, but checking 12V across initial power input gives me funny reading (5V or close to). I'm thinking a board fried and now I'm getting a short.

Any ideas on where to start to diagnose? If I unplug the boards from the power supply I get 12V across the power supply, so it's fine.
I have a separate stepper controller for the extruder motor.

Try the stepper controllers one at a time and see if they work alone. That would help you figure out i one of them is bad. It might be a problem with your power supply if you don't get 12 V with only one plugged in of it the voltage drops when you plug more than one in. Also, is your extruder controller plugged in too? Do you have the extruder heater connected?

Quote
brnrd
Your problem must be the A-D connection.

Thanks for all the info. I was able to scope the lines to and from the A-D and they appear to be working fine. I then pulled up the data sheet for the A-D and started testing connections on the board and found that T+ was not making a connection to the terminal post. Trying to fix it but it is really crambed in there. Wishing I had one of the newer A-D boards.

You're welcome. Maybe you can get techzone to send you a replacement.

But you should read my post about the problem with this A-D chip. The communication between the extruder controller and the the DS chip takes too long that i was getting a lot of timeout errors when trying to read the temperature.

I am supposed to get a replacement when I send this one back.

And I did see that post or another one somewhere else, I can't remember right now. I do have some thermistors around and have been looking at some of the docs on how to use them. Maybe on the weekend I will have time to do a new nozzle. That also means taking apart my x axis to swap it out.

Can't wait to print a new x-carraige this one is a real pain in the ass to make even the slightest adjustments to.

thanks for all these bits of info guys, it's been quite helpful to read through and get some new ideas.

One question I have though - I have the Gen3 Techzone boards, and from what I can see my Extruder heater output is constantly "on"... as in, I get a 12v measurement from my -C+ terminals at all times (and -B+ as well), and the green LEDs for both the B and C chips are always on.
This isnt a problem yet as I dont have my nichrome connected, but it seems that if i do, it will just heat up indefinitely?

My thermocouple is getting a reading (21ish usually) ... and I'm using brnrd's extruder Firmware, with the original 5D firmware on the MB. Is there somewhere I should be setting these to "off" or am I missing something?

(ps. I'm more of a 'craftsman' than an electronics whiz, so excuse my ignorance if i'm asking dumb questions, this is ALL very new to me)

Since the extruder and bed heaters are controlled by thermistors; and since you don't have the heating element installed; then if turned on obviously it will run continuously because the temperature it measures never changes. Adding just the thermistor won't change anything either for the same reason. Hook up BOTH the thermistor and heating element and I think you will find that it works properly.

---

Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
BLOG - PHOTOS - Thingiverse

noonan Wrote:
-------------------------------------------------------
> thanks for all these bits of info guys, it's been
> quite helpful to read through and get some new
> ideas.
>
> One question I have though - I have the Gen3
> Techzone boards, and from what I can see my
> Extruder heater output is constantly "on"... as
> in, I get a 12v measurement from my -C+ terminals
> at all times (and -B+ as well), and the green LEDs
> for both the B and C chips are always on.
> This isnt a problem yet as I dont have my nichrome
> connected, but it seems that if i do, it will just
> heat up indefinitely?
>
> My thermocouple is getting a reading (21ish
> usually) ... and I'm using brnrd's extruder
> Firmware, with the original 5D firmware on the MB.
> Is there somewhere I should be setting these to
> "off" or am I missing something?
>
> (ps. I'm more of a 'craftsman' than an electronics
> whiz, so excuse my ignorance if i'm asking dumb
> questions, this is ALL very new to me)

That's odd that your tip heater, C, is on even though your getting the correct temperature reading. When you first turn the power on or reset the extruder controller, it should set the all the tip and bed setpoint temperature to 0 so the output, A and C, for the the bed and tip heaters should both be off. I'm sure that the fan, B, should be off too. Is this happening even when you turn it one without connecting the MB to your PC? What happens if you send M104 S0.0 command? This should turn the C output off. Also the command to turn the fan, B, off is M107 and the command to turn it on is M106.

Edited 1 time(s). Last edit at 04/16/2011 12:29PM by brnrd.

"That's odd that your tip heater (C) is on even though your getting the correct temperature reading. "

...that's what i was thinking (as i said, i'm pretty new to electronics, but logic tells me that a temp of 23 with no command to 'heat up' shouldnt equal it being permanently powered up).

I have just plugged in the 12v adapter, no USB connection to pc and yes, both -B+ and -C+ lights are on and there is 12v at the terminals on the ext board and the A-D board.
When I plug in the USB and send the M104 command via the repsnapper input (thats what i should be doing yes?) I see the following in the comm log (is that ED etc bit some sort of clue?) :

12:20:46 Send >>Sending:M104 S0.0
12:20:48 Send >>Sending:M105
12:20:48 Send >>Received:T:18 B:0 with parameter 18 B:0
12:20:48 Send >>Receivedk ED H0I! with parameter ED H0I!**************************************
12:20:51 Send >>Sending:M105

... seems like the B and C LEDs are on whenever the 12v is connected... so maybe its a firmware issue?

when i 'switch heat on' and then 'switch heat off' with repsnapper it makes no change to the LEDs or 12v output

12:26:53 Send >>Sending:M104 S200
12:26:54 Send >>Sending:M105
12:26:54 Send >>Received:T:18 B:0 with parameter 18 B:0
12:26:54 Send >>Receivedk ED H0I! with parameter ED H0I!**************************************
12:27:08 Send >>Sending:M104 S0
12:27:09 Send >>Sending:M105
12:27:09 Send >>Received:T:18 B:0 with parameter 18

i'm using the Techzone A-D OneWire, a thermocouple and the techzone extruder controller, if that helps.

sorry, one more bit of info. When i first fired it all up I had a short (i think) in my heater wire setup. The CAT5 that came with my kit has the brown wires switched, so follow the 'twist the solid wires together' guide gave me a bad connection.
The C chip got super hot, but didnt smoke, then i tried the B terminals (oops)... so perhaps they're just faulty now, instead of dead?

ED is an error message. I think it indicates a timeout error in the RS485 communication between the MB and extruder controller (EC). It probably didn't have enough time to complete the transfer before the MB or EC had to do something else. Since you're getting a temperature reading, your Thermocouple AD might be working. Try unplugging the Cat5 (RJ45) connector. You should get a reading of 2000C. That would confirm that it's working.

Also, see if the C and B indicator lights go off when you unplug the RJ45 connector to the AD board. If so, disconnect the heater wires from the EC and plug the RJ45 back in. You should get a temperature reading again and perhaps the C light won't come on anymore.

Noonan,

We've had some similar issues lately with Techzone Cat5 cables being different or wacky in some way and subsequently shorting something in the extruder controller - We're still looking into it, but the current theory is that any initial heating attempt with wacky wiring may be blowing the associated transistor, forcing the heaters to drive all the time after this.

We're looking into how hard it is to repair one of their boards after this happens, I'll try to update when I know more.

When you power up your system with a working set of electronics, the LEDs associated with the A,B and C terminals will initially light up and then go off. You say that both your B and C terminals continue to be powered after this without any commands sent - Did you ever have anything plugged into the B terminals?

The general pattern seems to be - accidentally short the C terminal through some means, blow that transistor, and have it constantly on from then on. The chips used there are not current limited really - we're looking into more robust replacements.

Thanks guys, here's the answers :

brnrd - thermocouple is working, plugged in = T 0, unplugged = T 2000. Nothing I do will get the EC LEDs to switch off, other than unplugging the 12v input.

EtherDais - that sounds pretty spot on for a diagnosis. Yes, when the -C+ wasnt heating my board I tried the wires in the -B+ terminals just to check... seems I killed both chips in the first 5 mins.
They did start on, then turn off, then turn on to try to heat the tip, and have never turned off since.
... and as you've said, my cable only had the brown solid/striped wires swapped, which annoyingly is easy to skim over when you look at the cable and go "orange, orange, blue, blue, brown, brown..." without noticing that they're swapped. Easy assembly error for Techzone to make, but with major ramifications it seems......

Looks like i'll need to order a new EC... unless I can use the -A+ terminals to try a heat up test, and deal with not using a heated bed for now? is that just a firmware coding thing?

Yes, you can modify the extruder firmware to use the A +/- terminals. It's assigned to the heated bed by default but you can just swap them. I'll take a quick look at the code and I'll post the mods.

In the end of configuration.h in the extruder folder, it defines the assinments for the MOSFETs.

Quote


// MOSFET drivers

#define BED_OUTPUT 15
#define FAN_OUTPUT 11
#define HEATER_OUTPUT 12

Just change 15 to 12 and 12 to 15.

I recommend that you contact techzone. They seem to be reasonable about these things and they would probably replace your EC if you explain what happened.

Edited 2 time(s). Last edit at 04/16/2011 07:07PM by brnrd.

ah, good to hear and thanks for the code changes... i'll try it out later today and see how i go.

If its all working (with 2 fried transistors) i'll see what techzone can do for me. I have heard that they're pretty helpful.

I'm trying (without success) to get good prints using Skeinforge 40 for Gcode conversion and repsnapper to send codes to the printer. Is anyone here running the same thing and able to get good parts printed out? If yes, would be eternally grateful if you can share:

1) Your Skeinforge 40 profile(s)
2) Any tweaks you have to make to the gcode after generating with Skeinforge

This seems to be one of the last major hurdles for getting my laser cut Techzone mendel printing the way I'd like it to...

Noonan,

We have repaired these sorts of problems on TZ Gen3 Extruder Controllers: Documentation is here:
[reprap.org]

WLS,

You do get reasonable Repsnapped models right? We find that's a helpful double-check to make sure things are more or less functional before trying skeinforging it. Here is the current post of the settings we've been toying with:

*Edit: Damn BBcode, try this: [reprap.org]

Edited 1 time(s). Last edit at 05/03/2011 08:21PM by EtherDais.

Hey guys, I have most of the mechanical built on my techzone lc mendel after a bit of looking at the limited documentation on it and lots of trial and error. Things went pretty well overall but they never shipped me any bed springs. I've got a pile of metal springs in my garage and I'm just wondering how stiff they should be? I'm assuming the springs are there if you bottom out the head into the bed?

Noonan,

I've been having the same problem with my TechZone machine. I reached out to Lambert at TechZone for help, and here's what he shared with me:

"The photos make it look like it is not extruding enough, and that it is pausing too long when it changes directions/levels etc. I still recommend RepSnapper to send the gcode files. generating them in Skeinforge is a good place to make them, but it can take WEEKS of learning to get all the settings as they should be. Have you used www.3dtoolchain.com ? it uses skeinforge on the backend, using the settings I use, then it allows several adjustments for your specific printer. We have taken into account the new skeinforge formula for the steps on extrusion, if you have not changed your firmware, then do not use the volumetric. When we look at what they have done, we think it is a bit silly since it is just a multiplicattion of the steps and doesn't actually make a difference on the resulting gcode (you can multiply or divide the extrusion steps manually after the fact to get the same effect)."

I setup an account at 3dtoolchain.com, uploaded a file and had it generate the code. I was all excited to hopefully print a good part. I plug in the power source to my machine and got a series of 3 flashing lights and lost power. I obviously burned something out. That was on April 9th, and I haven't had time to work on it since. I'm hoping to this week. Give the 3dtoolchain a try and let me know how it works. If you've figured it out another way, it would be great to share. The learning curve is steep on these machines.

Chase82:

They don't need to be too springy, but it helps if they have a little bit of give. I think the main point is to have contact at the corners under compression so that you can fine tune the table balance.

Waconia Barret,

Did the flashing and shutting off only happen when you tried to power up the hot tip?

Chances are, the heater wire order was swapped: TechZone was sending out cat5 ends that matched the documentation on the hot tip assembly page, however they have recently also had some with two of the heater wires swapped:

The net result is that instead of heating the tip you short out your power and the supply has some kind of protection built in which will kill the system. I can't be sure that this is your problem, but it's something to be aware of.

Other techzone lasercut wooden mendel users: We've been finding that the first thing to go is generally the y-axis. Check out the OpenY design, and consider printing one before yours goes.

Now that I've basically finished assembly of my TZ Mendel, I've just discovered this forum. I wish I had discovered it several weeks ago. There were many things that would have saved me quite a lot of time if I had some good instructions. As it was, I found stuff on the internet with older incarnations of the printer that had different parts in various places. A number of times, I figured things out by putting things together until I got to something that wouldn't work and partially disassemble back to mach changed I had figured out. I have to agree with the previous poster talking about the axis supports being made with popsicle sticks. I don't yet know whether they will work satisfactory, but they seem rather flimsy for the job. But if they work in production, I won't complain.
I'm at the point now of getting the software loaded on my laptop. I saw somewhere that there was special firmware needed for the TZ extruder (the wooden-block model). Does anyone know whether that firmware comes pre-loaded or do I need to figure out how to compile and load firmware before I start?
I haven't even applied power yet to give it a smoke-test, but I'm pretty experienced with wiring and don't anticipate problems. I've seen some questions about whether the stepper drivers have satisfactory heatsinking as delivered, so I will cut up some larger heatsinks to glue to the chips before I power it up.
During one of the assembly/disassembly iterations, I damaged one of the wooden stepper gears that came with the kit. There was a spare gear included, but it had been cut on a slant, so I didn't want to use it. I'm fortunate to have a small laser engraver at work that can cut 1/16" plastic, so I made a stacked-wafer gear to replace the one I broke. You can see it at thingiverse.com # 8389
Anyway, any comments are welcome, and I'll be glad to answer any questions that I can. I'll probably be most helpful in describing how not to do things. :-)

Follow-up to my previous post: I just heard back from Kurt at Techzone and he confirmed that the special firmware is already pre-loaded. So that's a big load off my mind.

There are several iterations of techzone firmware floating around as well, should you find that you want to reflash either the motherboard or the extruder controller. Check brnrd's posts for important changes to the code.

How does one contact Tech Zone Communications? I've tried their contact form at [www.techzonecom.com], but with no email response, and no feedback from their website, I've really no idea if it's working.

Does someone have a working email address for them?

Also, does someone know where they've documented changes to their kit? The z-axis parts I received are quite different from what is shown in [reprap.org] and [reprap.org], and I'd like a bit of guidance for assembling them.

I'd like a bit of guidance for assembling them.

Hmmm ... did you try:
http://reprap.org/wiki/LaserCut_Mendel_Assembly_For_Complete_Beginners?

---

-Sebastien, RepRap.org library gnome.

---

Remember, you're all RepRap developers (once you've joined the super-secret developer mailing list), and the wiki, RepRap.org, [reprap.org] is for everyone and everything!

Actually, I found that Ulrich was shipped what appears to be (mostly) the same kit that I was, and the photos that he posted were quite useful for making sense of the z-axis.

Now, my problem appears to be one of missing parts - which means I'm back to trying to figure out how to contact Tech Zone.

[edit] Looks like the parts might not actually be missing - just morphed into something very different - [www.thingiverse.com]

Edited 1 time(s). Last edit at 05/15/2011 03:42AM by raldrich.

Having just reached the electronics portion of my build, I find myself wishing that TechZone had assembled the cables for me.

The suggested method (use a small screwdriver to push the wire into the connector) has a high risk of failure, and I really don't want to spend my time debugging bad cables.

So, I went searching to find the correct tool - lacking any documentation on the connector type, it was a bit of a long-winded search.

My result: an MTA-100 T-Handle Crimping Tool - [www.alliedelec.com]

Hopefully, someone could verify whether or not this is the right tool?

- Ron