LaserCut Mendel by Tech Zone Remix

Hi folks, I'm new here. I purchased a laser-cut Mendel parts kit from TechZone, and am mid-way through the assembly process. It has gone well so far, but I've hit a bit of a snag and I could use a little help. I emailed TechZone about this late last night but I'm guessing they're pretty busy these days, so I figured I'd ask here.

My Z-axis bars are out of alignment; I set their spacing to 398mm at the top per the Mendel build spreadsheet but at the bottom they're too close together by about 5mm, which causes them to miss their holes in the Z-axis leadscrew bases as well as the bearings in the X-axis assembly.

I set the distance between the frame vertices' inner faces to 234mm as detailed by Deland Craven's frame assembly page here:

[delandcraven.com]

This results in a center-to-center spacing of the threaded rods of just about 250mm. This is the dimension that controls the spacing of the Z-axis leadscrew bases, and in turn, that of the Z-axis bars, so I'm thinking that spacing may be incorrect. I'm not about to go adjusting the frame left/right spacing without knowing what it actually should be, though. Of course it's also possible I've simply misunderstood something.

I would really appreciate some advice. Can anyone give me a clue?

Thanks,
-Dave McGuire

EDIT:
I messed around with it a bit more tonight. The 234mm spacing between the inward-facing frame vertices came from the Mendel assembly spreadsheet as "J2"; I missed where that had come from. If I work from right to left from the rightmost Z-axis bar making everything line up with 398mm between the bars (assembly spreadsheet parameter "M1"), at the top and bottom, everything looks ok but the "J2" measurement is actually 240mm, not 234mm. Where did that extra 6mm come from? Is it possible that the laser-cut Mendel build results in this parameter being different? (I'm fine with that; I just need to know) Would someone please whack me with the Great Baseball Bat of Clue(tm)?

Edited 1 time(s). Last edit at 01/11/2011 10:39PM by mcguire.

I actually didn't pay attention to dimensions. I just left everything as wide open as it could possibly go. I left the nuts finger tight and squared up the axes after I had everything assembled. Then I tightened everything down with wrenches and lock-tightened the stuff I was sure would not be needing adjusted again. I didn't have calipers big enough to get good measurements on most of it.

As long as your dimensions match with other dimensions that you have on your machine such that everything is either perpendicular or parallel, and your build table has enough clearance, I wouldn't get too tangled up in "official" dimensions. If a dimension is way off (IE 30+ mm) or your build plate does not have enough clearance, then you might have a set of rods in the wrong place or something, but otherwise I wouldn't get too concerned.

Edited 1 time(s). Last edit at 01/12/2011 05:07PM by dazed.dnc.

I did the same as dazed

Was so eager to get the thing printing by that stage (READ LAZY). Once the frame was assembled and the nuts finger tight, I just used a cheapo square ruler and my eyes to straighten out the assembly.
I did pay a bit more attention to getting the print bed level though (using a spirit level).

Understood, thanks guys. I really appreciate your input. I've gotten my X-axis assembly mounted and it rides nicely, and everything seems to line up. Now I'm working on the Y axis.

I noticed tonight that the wooden gears slip badly on the stepper motor shafts. Clearly this isn't going to work at all without some magic there. Did you guys run into that? If so, how did you address it?

Thanks,
-Dave

---

--
Dave McGuire
Port Charlotte, FL

I used aryldite (epoxy) on my x motor and just press fitted my y. The y has given me trouble so I ended up epoxying it last night.

I'm not familiar with aryldite, but don't use anything *too* strong. If you need to pull the gear off for some reason, you want to be able to remove them. For example, mine were not cut very well. It looks like the laser cutter was not perpendicular to the workpiece. If yours are the same, you might decide that you want to replace them. I used a couple of drops of super glue. It was strong enough to prevent slippage, but brittle enough to break free if I pry on it with a screw driver.

Also be careful that none of it drips back toward the motor housing. A thin glue might wick into the bearing and lock it up. Viscous glue will stay on the surface giving you a better shot at being able to chisels it out. At any rate, you can avoid some headaches by keeping the shaft pointed to the floor until it has dried.

Edited 1 time(s). Last edit at 01/13/2011 05:58PM by dazed.dnc.

Hello,

I'm working on a laser-cut Mendel using acrylic. I have two questions.

1. For the X-Axis 180 End, 360 End and Bar clamps, I routed grooves too deeply. Now the Bar clamps don't really clamp. I was wondering if using a 1/8" piece under the 180 End and 360 End instead of a 1/4" piece would throw off the alignment for the belt. See attached image.

The reason I am asking this rather than simply routing new pieces is to avoid asking my friend to help me laser cut more pieces. I ran out of spare bar clamps.

2. For the captive nuts on the 180 End and 360 End, I was wondering if there is ever and issue of the the captive nut sliding up and down within the space it has. See attached image as well.

Best,
Jack

Edited 1 time(s). Last edit at 01/16/2011 04:08AM by jacksam.

I did the exact same thing to my wooden pieces. I fixed it by grinding two edges of that spacer so I did essentially the same thing. Using a thinner plate there might effect the x-to-z axis constraints a bit though. I would have to draw something up to show you what I mean. You might want to drill out a new spacer from your 1/8" material. It doesn't have to be as complex as the original one. You could probably even use a stack of washers or something. Use your laser cut one underneath the entire assembly to get a little more side-to-side stability out of it.

As for the nut, mine was a tight enough fit that it never moved around but they are made from wood. For acrylic, having something that tight will probably cause it to fracture. File it open a bit so it slides in and out freely. Gravity should keep it held steady unless your tool head crashes or something - in which case that empty space might actually be useful for preventing damage. You can always print a shim or make something to fix it later if it is an issue.

I got my Techzone LC kit about 2 months ago. The actual 'building' was a breeze, but the extruder controller and motherboard are absolute shit. The motherboard works when it feels like it, the extruder controller wont do anything. Everyone seems to have their own opinion on which combination of firmware and software will work, sadly nothing works, and documentation is spotty at best.
Im this close to admitting defeat and buying the makerbot electronics, but you know what? I could have saved my time and just bought a thing-o-matic.

GIJED Wrote:
-------------------------------------------------------
> I got my Techzone LC kit about 2 months ago. The
> actual 'building' was a breeze, but the extruder
> controller and motherboard are absolute shit. The
> motherboard works when it feels like it, the
> extruder controller wont do anything. Everyone

My techzone remix gen 3 kit is working fine on the firmware that came with the reprap host 64-bit 20100719 version.

GIJED Wrote:
-------------------------------------------------------
> I got my Techzone LC kit about 2 months ago. The
> actual 'building' was a breeze, but the extruder
> controller and motherboard are absolute shit. The
> motherboard works when it feels like it, the
> extruder controller wont do anything. Everyone
> seems to have their own opinion on which
> combination of firmware and software will work,
> sadly nothing works, and documentation is spotty
> at best.
> Im this close to admitting defeat and buying the
> makerbot electronics, but you know what? I could
> have saved my time and just bought a
> thing-o-matic.

I know your pain. I got so many communications errors on my original tech zone electronics that I switched to the RAMPS kit before even attempting my first print. It doesn't use serial communications between two boards, so I figured it would be a bullet-proof fix for the problem I was having.

That said, not every problem is the fault of the manufacture. It is easy to install something wrong or accidentally break things and if you didn't know what went wrong its easy to assume that it is a manufacturing defect. I don't mean to accuse you of anything, but lets not bad mouth a product if the real problem is plain and simple operator error. Maybe we can help if you share more details about what is going wrong?

It is aggravating that these things happen, but To some extent, I think you have to expect trouble no matter what 'bot you get. Your talking about a technology that ordinarily sells for in the $10,000 range. A $700 equivalent is not likely to go off without a hitch.

I had a lot of problems with the electronics, too. I got to looking at the schematics, though, and I noticed that there's no common Ground between the extruder controller and the motherboard(Or if there was, it wasn't sufficient. It's been a while.). Anyways, I added one between the two.

Near the programming header on both the Extruder Controller and the motherboard, there's a 2x3 array of holes, don't remember what they're for at the moment. Anyways, one of them is square where the others are round. You want the hole that's 'opposite' this one. If the square one is in the top-right, you want the bottom-left one, and so on. Solder in a wire between those holes, and see if you still have problems. It greatly reduced the communications errors I got.

One of the 4 wires that connect the motherboard to the extruder controller board is ground. I mounted all my boards next to each other on the side of the Mendel as in this picture to keep the wires short.

No... Unless the RS485 connection doubles as a ground... [reprap.org]

Quote
izzy84075
No... Unless the RS485 connection doubles as a ground... [reprap.org]

You're right. There's no ground connection between the motherboard and extruder controller. I guess the ground connection is through the 3 stepper motor controllers since they are all connected together through the 12V power supply and there are many ground wires in the ribbon cables between the motherboard and the stepper controllers. I guess I don't have a problem since I mounted all the boards next to each other. I suppose this could be a problem if you mount the boards in the usual Mendel locations.

brnrd Wrote:
-------------------------------------------------------
> My techzone remix gen 3 kit is working fine on the
> firmware that came with the reprap host 64-bit
> 20100719 version.

Ok, so your hardware didnt require bullshit compiling with Ardiuno?

Quote
GIJED
Ok, so your hardware didnt require bullshit compiling with Ardiuno?

I actually followed the instructions on the wiki to load the firmware with Arduino. But I wasn't sure if I was successful in loading the firmware to the extruder controller so I contacted them. I learned from Lambert Andrus that the boards were already loaded with firmware and are ready to go. In my experience using different versions of the reprap host, however, the host sometimes didn't work unless you load the firmware that came with the sw version. I also had to change the thermistor table since the thermistor that came with my kit didn't give the correct reading with the default table in the reprap host firmware. When I swiched to ReplicatorG/Skeinforge, I learned from this forum that I needed to turn off acceleration in the firmware, so I did.

Anyway, the great thing about open source is that you have access to such things so that you can not only support yourself, but also change the sw/firmware/hardware to improve things or make them to your liking. You also have a big community that can help you. As dazed.dnc suggested, if you can describe your problem in more detail, the people here might be able to help you better.

Ok, heres my problem; Reprap host software doesnt work at all, never did, turning on coms debug gives me this message "N0 M110 *3 dequeued and sent". That's it. I then heard that maybe my firmware wasnt talking to reprap host, so i tried to update it. However Arduino throws a fit and wont compile, giving me a million little errors that go something like "blah blah wasnt declared in this scope" and "operator == has no left operand". No help there. So then i try Replicator g and holy shit i can move the x and y axis. My joy is short lived because now i cant move the z axis, the extruder wont turn, the tip wont heat up, and i cant get a temperature reading. At this point i see that one of my stepper driver controllers is smoking. Not surprisingly it was the z axis. Ok, so i order a new one. Still wont move, but at least it wont burn my house down. I then notice that when i tell the z axis to move it sort of hums, so i figure i broke it when i put the gear onto it. So i order a new stepper motor. Still wont move. Still just hums at me, mockingly. Then i try to solve my extruder problems by ordering a new tip kit because i heard that they were quite finicky. Still no temperature readings, still no heat from the tip.

At this point, months and hundreds of dollars later, still nothing works. You're god damn right im pissed off.
Ive spent so much time trying to decipher that fucking firmware. Oh and i wish this kit only cost me $700, i spent over $1200 on something that doesnt even work, money that could have got me some hookers and cocaine.

Ive trippled checked all my wires, ive done everything. What you guys suggest?

Quote
GIJED
However Arduino throws a fit and wont compile, giving me a million little errors that go something like "blah blah wasnt declared in this scope" and "operator == has no left operand".

Did you copy the file configuration.h.dist to configuration.h? You have to do this in the FiveD_GCode_Interpreter and the Extruder folder. Also, did you install Sanguino?

brnrd Wrote:
-------------------------------------------------------
> > However Arduino throws a fit and wont compile,
> giving me a million little errors that go
> something like "blah blah wasnt declared in this
> scope" and "operator == has no left operand".
>
>
> Did you copy the file configuration.h.dist to
> configuration.h? You have to do this in the
> FiveD_GCode_Interpreter and the Extruder folder.
> Also, did you install Sanguino?


Yes.
This is what i see:

What firmware are you compiling? Did you change the code? I don't see the error telling you to select Sanguino in the tools menu so I assume that you have it installed and selected. I also noticed that you're using Arduino 0022 while I'm still on 0021. Have you tried 0021?

It looks to me like you haven't properly modified "Configuration.h" for your system:

//#define DEFAULTS DARWIN_DEFAULTS
//#define DEFAULTS MENDEL_GEN3_DEFAULTS
//#define DEFAULTS MENDEL_MEGA_DEFAULTS
//#define DEFAULTS BATHPROTO_DEFAULTS

One (and only one) of the above lines must be uncommented!

---

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

I don't see those lines in my configuration.h from reprap host 64-bit 20100719. This is what I see:

// Here are the Motherboard codes; set MOTHERBOARD to the right one
// A standard Mendel is MOTHERBOARD 2

// (Arduino: 0 - no longer in use)
// Sanguino or RepRap Motherboard with direct drive extruders: 1
// RepRap Motherboard with RS485 extruders: 2
// Arduino Mega: 3

#define MOTHERBOARD 2

Sorry, I was looking at the newest 20110207 release.

---

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

You have done something seriously WRONG.

You have error messages that indicate that CPUTYPE, ENABLE_LINES and EXTRUDER_CONTROLLER are not defined but these are not anywhere in any of the 64-bit\20100719 firmware source files!

As a matter of fact, all three of these defines are ONLY in the newest firmware version reprap-mendel-20110207!!

So somehow it looks as you have copied different versions into the same directory.

---

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

@rhmorrison: You're confusing my post with those of GIJED. The 64-bit 20100719 version is working for me. I was letting him know that that one works with Arduino 0021. I don't know what firmware he's trying to compile. But since I read your message, I tried downloading the newest release and I can't compile it in 0021 either. It seems that this latest version is harder to work with.

@rhmorrison: No i have not somehow mixed different version of the firmware together. All i have done is follow the instructions, the first of which was to uncomment one config; which is why my code looks like this:

// pre-select a typical setup from the below list
//   using typical pinouts and typical capabilities. see features.h for what typical setups we have available
//#define DEFAULTS DARWIN_DEFAULTS
#define DEFAULTS MENDEL_GEN3_DEFAULTS
//#define DEFAULTS MENDEL_MEGA_DEFAULTS
//#define DEFAULTS BATHPROTO_DEFAULTS

But ill take Brnrd's word for it and try to compile 20100719 with 0021.

Thanks for all the help, guys.

@Brnrd Haha you magnificent bastard that firmware worked like a charm. With a little messing around with my endstops i was able to get full control of the axis. I damn near crapped my pants when i saw that z axis move.

Anyway, now to tackle the extruder. The firmware for the extruder compiles without a hitch but it wont upload to the board.

Binary sketch size: 7174 bytes (of a 14336 byte maximum)
avrdude: stk500_getsync(): not in sync: resp=0x00
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

From what i can tell, this is a pretty common error, most people say to reset the board as you upload or burn a bootloader. Bare in mind ive never even tried uploading to the extruder controller before, this is how the board came from techzone.
Is this something you've encountered before?

Quote
GIJED
@Brnrd Haha you magnificent bastard that firmware worked like a charm. With a little messing around with my endstops i was able to get full control of the axis. I damn near crapped my pants when i saw that z axis move.

Anyway, now to tackle the extruder. The firmware for the extruder compiles without a hitch but it wont upload to the board. board.

That's great! We should be able to make the latest firmware compile also. Has anyone successfully compiled the latest firmware for Gen 3 Mendel?

As far as the extruder, did you connect the USB-Serial board directly to the extruder controller? Also, did you select Arduino Diecimila in the board menu? I think you have to disconnect everything else from the extruder controller including the 12V supply. Also pay attention to the polarity of the connector by matching the white dots on one end of each connector to each other.

Edited 1 time(s). Last edit at 02/11/2011 07:17PM by brnrd.

Does anyone have photos of how to connect the oak block to the extruder body on the TechZone Wade's extruder?

This has me completely baffled!