LaserCut Mendel by Tech Zone Remix

Tom Wrote:
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> 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!

I would recommend getting another hot end, especially if you want to print with ABS. Barrels for aging some alcoholic drinks are toasted at around 230c, which is pretty close to the temperature used for printing ABS. After a few months of holding your nozzle, I'm willing to bet the threaded section of your oak block starts to char and shrink or become weak. It shouldn't spontaneously combust or anything, but I wouldn't count on it lasting very long.

Take a look at this thread for more details, but the short and sweet version is that you need an insulating material that will withstand at least 230C continuous exposure. Popular choices for this are the "hybrid" peek exterior and PTFE core insulator or the newer hot end design seen here (towards the bottom of the page).

That said, if you want to use oak anyhow, I think mine was screwed to the extruder block using two wood screws that went through the left and right sides at an angle. You can probably just glue it on too, but you won't be able to remove it if you need to. Either way, I suggest putting a piece of filament down the center to keep things aligned while you work on it.

Edited 1 time(s). Last edit at 02/16/2011 08:19PM by dazed.dnc.

Thanks Dazed!

This will be extremely helpful. Angling wood screws from the top was about the only way I could conceptualize, but the Wiki didn't really explain it that way. I also like your advice on the replacement. I'm going to mount the wood block version tonight to be able to finish the setup and calibration, and IMMEDIATELY work on one of the improved alternatives for actual use.

There's an alternative way to mount the TechZone tip that seems to be poorly documented, but very stable:

Step 1: Screw the 'tip adapter' piece into the wooden block, using two screws which pass through the thin edges around the teflon insert.

Step 2: Use the mounting holes on wade's extruder to pass screws through the tip adapter. If the screws in step 1 were placed correctly, these second mounting screws will not interfere with the first set.

This guy burned his thermocouple, but you can see the way in which it is mounted, basically: [delandcraven.com]

@tom, what do you mean mounting? do you mean the oak block to the wades extruder? if so i have my extruder apart now and can take pictures, how ive always done it is by drilling the screws in to the oak so that they are at 90 degrees to where the screws would go to drill the tip adapter through the extruder, then drill the holes through the extruder as normal and use screws. as dazed said, the oak does eventually fail, the block chars and the threads slip and nozzle goes south towards your bed... im still deciding how to manage a new design that doesnt require machining or special parts...(PEEK would be nice but i cant find a pre machine blank) one thing to be sure is to bring the wires to the one side of the block so the block fits in the x carriage and the wires come up from the back, so it doesnt interfere with the gear. also, if you have your x carriage off to install your extruder, heres a quick tip, get some bolts and standard nuts, and pre drill half way through the place the nut goes on the bottom of your extruder carriage with a bit about the size of the nut, then use a few washers and the bolt to pull the nut in to the wood, making a threaded insert for your x axis, so next time you need to pull the extruder, its a much simpler ordeal, if you would like pictures of either of these processes, let me know, i have my parts pulled apart to do the exact same repair, this time hopefully for the last time for a while.

@nuts

Yes, mounting the wood block to the wades extruder. If you still have it apart and could snap a picture or two that would be great. I also like the mods you're talking about on the x-axis carriage. It's a real pain to take it apart now. Any photos of that would be great too.

Thanks!

Tom

ok, i do still have it apart, so ill pull the camera now, the nut within the wood mod has worked very well, makes any extruder problem just that much easier. ill have the images up in a few mins. let me know if there's any other explanation you need. i built my machine with very little instructions, mostly 3 or 4 images of the parts completed, so i've made almost every mistake in the book. i only showed the nut embedded in the easy side of the extruder, i did do both sides but because of the bearings, the other mount is harder to photograph, but the process is exactly the same for both holes, just don't pust hard with the drill, you only want to go through enough to cover the nut since its laminate wood, its easy to stop half way, as of now i do not remember the size i used for my nut/bolts, they are either 10-24 or 8-24, they're very close to the size of the small bolts for connecting your motor, they have a shallow and wide nut, and they're standard Phillips.

Edited 1 time(s). Last edit at 02/22/2011 03:14PM by nutz4hs.

i hope these are helpful to you. like i said, any other help you need, don't hesitate to ask.

Thanks! This answers alot! I don't have the white piece on the top of the oak block, which is why the 2 screws that go through it and the Wade's extruder base do nothing for me. From the previous written explanations I thought I had to angle wood screws through the actual extruder base into the wood block, which is very difficult to do without getting in the way of the motor or the block that holds the bar to hold the bearings in. Unfortunately I "sort-of" screwed the block onto the extruder base and then used some epoxy around the edge to hold it stable. Then I saw your first post! I'm getting good with modifying/redoing using my dremel tool, and I know it takes epoxy off well, so just a little more work, and get the top white piece from Lambert at TechZone.

Tom

the white piece on top of the barrel is called the tip adapter, in the old kits they were printed out of abs, now theyre just chunks of ptfe tube, seeing as you dont have one, i can now understand your confusion. also, does your kit have metal bed springs or wooden? the old kits had wood and were prone to failure, they have now switched to metal ones, and if you have the old style, it may be a good time to ask for new ones. good luck!

Fortunate for me, I just ordered 2 "tip adapters" along with some spare nichrome wire and thermocouples and tips last week. I thought the tip adapters might be nice to have someday (wasn't sure what for). Now I'm REALLY glad I bought them. They were just delivered today. Yes - I DID receive the wooden springs. I'll ask Lambert for some metal ones. FYI - I also had my extruder controller "pop" on me. Apparently this is common, because sometimes the extruder motor will draw more amps than the board is rated for, so I've gone to the route of using a 4th stepper controller for the extruder motor. I've heard it runs much better that way. Once I get it back together I'll post the results.

During my "downtime/stuck time" I switched to a different PC and now every time I have RepRap software running and plug in the USB cable, I get the blue screen of death. UGHHH! I posted another thread about it. So now I can't even communicate to try everything out. Once I get that figured out, I have one of the endostops working and need to get the other 2 working and I'll be ready to calibrate and try printing.

Tom

i've seen the other thread, i would bet the motherboard is damaged, i would try to unplug all connections except the serial and slowly plug things back in, even trying a new usb cable and checking the idc cable for shorts or bad connections, i hope you have a multimeter, if not theyre cheap and extremely handy for building and running one of these machines. I also went the route of using a 4th stepper controller, using the old h-bridges caused the entire board to get so hot, it wasnt worth the risk to me. where are you located? i may have a board and some of the connections you can borrow to find your problem cause. also, if your brave enough, you really should remove the blown hbridge, you can slice the legs of the chip with a razor knife and simply remove the chip, this is to make sure you dont cause any shorts with the bad chip. if you would like, maybe we can try to meet on something with a faster turn around, (yahoo chat or aim) in the next few days, to see if i can help you diagnose the problem. let me know, and good luck with the project, glad to hear you mistakenly ordered extra tip adapters.

I'm trying a couple of different things with the USB to serial converter driver. Still no luck. I'm going to try to get my other laptop to communicate with the Mendel and see if the problem goes away. At least that way I know if it's the motherboard or not. This whole thing started when my RepRap software on my Windows 7 64-bit laptop with Java 6 was "hanging", so I tried uninstalling Java, reinstalling Java 5 as per the Wiki. Now, whenever I try running the RepRap software I get the error that it can't find Java. I've even added the paths manually for Java and no luck. So then I switched the other laptop (which is the one I plan to use long-term anyways). That's when the bs of death started, so I"m hoping it's a driver/hardware issue on the laptop.

I do have a multimeter and have been using it religiously through the build, so I'm feeling good electrically. If the other computer still gets the bs of death, then I'll swap out motherboards. I have a complete 2nd set of electronics, since I'm planning on building a 2nd one for my son's school.

I'm in Minnesota, USA. Haven't heard of anyone locally with a RepRap. If you happen to be close by, I'd forward to meeting you to exchange stories, ideas, and at least buy you a beer for your help!

Tom

Tom,

Are you using the Monotronics or the Gen 3 Techzone Remix Electronics?

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-Sebastien, RepRap.org library gnome.

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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!

Gen 3 Techzone Remix Electronics

I doubt if the blue screen of death has anything to do with the motherboard. That sounds like a sw problem to me. Have you tried communicating with the Mendel using Arduino or repsnapper instead?

I think I've ruled out the motherboard. I've disconnected the motherboard from the USB connection and still get the BS of Death. When I connect the cable to my other laptop it's fine, although I can't get that laptop to run Java anymore (it originally did when I was building my Mendel). I've uninstalled and reinstalled Java 5 and Java 6 several times, added the path statement for the Java location, and still can't get that laptop to recognize the Java command when the RepRap software starts.

I changed USB cables and still get the same thing. I've tried communicating with it via Arduino by uploading a file and get an error about the baud rate, so I'll work more tonight on communicating via Arduino. I also disconnected the USB from the usb port and just plugged it into the pc with RepRap software running and didn't have a problem, so I think it's something to do with the USB to Serial converter that loads when connected to the USB port. I found a thread about FTDI issues with Windows XP so I've downloaded a new FTDI driver but can't get it to install. That's where I'm going to focus next and then try communicating.

I'm also going to try a 3rd computer tonight to see if I can that one to communicate.

now that you've done all that, it definitely seems like a driver issue, most likely the serial-usb converter. i think we're in the same boat, but different states, im in Phila, PA but havent heard of anyone outside of expensive hackerspaces that have one. You can maybe try uninstalling the driver and finding a new one, its very weird to get it to BS instantly from plugging it in. good luck, ill keep popping in and out of here to see if you have any other questions. or you can email me :nutz4hs (a) yahoo (dot)com so we can swap stories or debug issues.

Does anyone know where I can get the assembly instructions of Techzone mendel. I recently purchased a kit and they have new parts, different, then the laser cut mendel describe at reprap.org

Techzone said that they are providing instructions but hasn't happened yet.

Do not know why they would change the kit before providing the new assembly instructions.

thanks

@rista which model do you have? mendel or huxley? TZ is generally very bad at providing instructions for the machines (the instructions for their site link to a half completed and very un organized wiki),you are much better off looking around the forums and asking people as of right now, pennstate university is building a huxley and several mendels, and heavily documenting it, you might be able to get in contact with them to ask for the build pictures.I bought a lasercut mendel a few months ago, built it with 4 pictures of various completions of other mendels around the web, so even if they say they are gonna provide them, i wouldnt hold your breath, you much better off tinkering than waiting.

Edited 1 time(s). Last edit at 02/23/2011 11:35PM by nutz4hs.

Rista,

As Nutz4hs mentioned, we are building two TechZone Mendels and one TZ Huxley for an Engineering Design course here at Penn State. The documentation for both of these units is still sloppy, but we are hoping to collate all the relevant wiki pages here in the process of reviewing the current material. Currently the relevant information is strewn over several wiki pages.

Please do not hesitate to PM me with any questions you have.

@rista I'm putting together a TechZone Huxley right now. I've been following instructions recommended by TechZone at this link: [reprap.org].

So far, I've gotten the frame together, installed the software on Ubuntu 10.10. Tested the motors by connecting them to the circuit board. They are responding to the software. Next, I'll be truing the frame and adding the electronics to the frame. I still have a long way to go, but so far, the documentation in the link above has been enough to get me to this point.

The problems I've had so far have been due to my inexperience with electronics and Ubuntu. My new friends at Berks Colab took some time to show me how to install software in Ubuntu and how to connect the motors to the circuit board. Those were my only hiccups. Even though the documentation isn't complete yet, they give enough pictures that help. Also, a few people have added comments to the wiki with added explanations and alternative suggestions.

As I get further along in the process, I will probably also reach out to the PennState crew for more assistance. But, so far, I've been fine with the instructions from the link above. Hope this helps you too.

@EtherDais could you post any instructions you have so far. Or maybe even update the wiki in the link above? In the meantime, may I PM you if I have any questions?

As far as the TZ Huxley goes, our main issues have been shortages on the included components (Hey, bean counting can be a beast). Double check your inventory, we are concerned that their packing list may have the number of bearings misabled. Feel free to PM me.

We are collecting images and video for updating the wiki build instructions, and I believe some small updates have been made already. As part of the class, students have been documenting the wiki. I'm hoping we can just create a "techzone Build" hub which links to the pages already made, if we cannot just combine them.

Currently, PSURUG has more background with the TZLC Mendel than the TZ Huxley, but we are learning.

On a different note: Has anyone found an STL for the previously discussed tip adapter piece?

Edited 1 time(s). Last edit at 02/25/2011 12:44AM by EtherDais.

hey
kinda related side question. how did you guys attach your completed extruder to your carrage. mine has a piece of filiment jamming it in at one end and seems very loose.
would lkove to hear of a better solution.....
thanx
~brian

@etherdais, i dont think they have released the stl file for the adapter, it was an old design, that under some issues failed so they are now using ptfe tubes as a replacement, although since the tip adapter is just a simple tube shape, it wouldnt be hard to dupe if someone required a part to temporally get the reprap printing. asking lambert may produce the file, or if needed, i may be able to make one up and throw it on thingverse.

The tip adapter is strange. In October when I got my LC mendel from Techzone there wasn't a tip adapter at all. The teflon tube extending from the oak block was butting up against the filament exit hole on the extruder, and there wasn't an obvious way to mount the tip properly. After I got another tip kit from them, they threw in the tip adapter and it all fell in place for me: I mounted it very similarly to your images above. I've been using the same tip adapter since, and only needed to tack on a bit more material to give the screws something to bite into once (after going through 3 tips with the same adapter).

If you're using a wood block design, it seems that the hot zone is a bit more confined than in a metal design where you have to start heat sinking. The oak block CAN warm and eventually warp the tip adapter - that being said, i think if the holes on the wade's extruder mount were placed closer together - just a bit - you'd get a better bite into the tip adapter, allowing for a more secure mount than seems to happen now.

I sort of assumed it didn't make business sense for TZ to upload any files for things they've made, so i wasn't holding out for it to happen. If you happen to sketch one up and drop it on thingiverse, it would be awesome if it had the holes in the right place so that it could be mounted securely, with a bit of recessed space for the heads of the vertical screws. Then again, perhaps you don't want the lateral holes at all, as I find it's nice when the screws really bite into the adapter. This would go into my "models useful for fixing TZ systems" folder.

next chance i have ill sketch one up. its a very simple design so im sure it should go smoothly. as for the holes on the sides that mount it to the extruder block, i think it depends on the holes through your extruder itself, mine seems to be slighly closer together than some, and i have never had an issue with the tip slipping, i did however have a problem with the part delaminating by running the extruder too cold, and i guess it just could'nt take the pressure of the wades stepper was putting out along with the cold nozzle. either way, i would only use this part as a temporary replacement, and even so would plan to print in abs, due to pla melting as the lower temps. since the design is simple enough, im sure with patience, one could build one with holesaw out of oak or other high temp capable wood. ill be sure to post a link of the part when i get around to doing it.

Quick update on my build.

1. Still haven't figured out BS of Death with laptop, but not working on it. Using other laptop with RepSnapper is working great
2. FINALLY got all 3 axes to home out. Found the ground wire on one opto was intermittent on continuity.
3. Got extruder oak block mounted. Thanks for the help on that!

Hoping tonight to melt some plastic!

I purchased a laser cut Mendel kit from Techzone about a month ago. I have been having problems with the host software. I can't connect to the printer using the reprap host software. I am able to connect and move all the stepper motors and extruder ONLY when using repsnapper. However, printing is still not possible as it seems to print one layer and stops. It moves to the next layer when I press the "kick" button.

I'm hoping someone can provide information on the following based on your experience with successfully getting the laser cut mendel from Techzone to print.

Do let me know:
1) The host software you are using (reprap host? repsnapper? Is it possible to use replicatorG?)

2) If you are using reprap host, can you please send me your reprap.properties file? I'd like to have a look at what settings you are using in order to get good print results.

3) If you are using repsnapper, can you give me some help on the settings that I need to look out for

4) What version of windows and do you use? I'm using Windows 7 and also XP pro. Which do you recommend?

5) Any other information you may have so that I can actually start printing something.

If you're using a Techzone remix, did you connect a ground wire between your motherboard and extruder controller? There are instructions here on the forum and probably also on the wiki on how to do that. You can solder a wire on one of the ground pins near the serial connector on the motherboard and then connect that to the gnd terminal for the power to the extruder controller.

I use a Mac with techzone remix and in this platform, I can only use the 20100719 reprap host 64-bit firmware.

After a couple of months, I've settled on using Skeinforge to generate G-Code and Repsnapper to send them to the printer. You can pretty much use it with the default settings except for adjusting the flow rate. If you're using PLA, then you need to change the termperature settings based on your PLA type and extruder tip. Beware that the new Skeinforge 040 changed the meaning of e0_steps_per_mm so if you download that, you either have to change this in the firmware or use flowrates that are about 36x or more larger than the feed rate. The reprap host I mentioned works for sending to the printer but not as well as Repsnapper. My only problem with Repsnapper is that it takes long to read a G-Code since it also interprets them for display. It would be nice if I can turn this feature off so I won't have to wait. If you can get ReplicatorG to work on your OS, then that would also be a good way. Unfortunately, I can't get it to send g-codes to my printer either.

WLS:

1. I have never had any luck with the official java software using the WinXP machines available. Repsnapper saved the day for my first build. I use replicatorG sometimes to quickly flip an STL that is misbehaving for some reason, but I still really use repsnapper for driving everything. (Skeinforge for GCode, once you get to it)

3. Settings in repsnapper: I've attached the XML file that repsnapper uses to store settings. If you put this in the directory you are running the exe from, you should be able to view/use the settings here.

5. Other things: What brnrd suggests is helpful in certain cases, but the securing the system ground with an extra wire is not usually needed for a successful build - so bear in mind that that isn't a cure-all, and it sounds like your problem is unrelated to that.

Questions for you:

-How freely does your Z-axis move when driven? (when using a manual +-1mm in repsnapper for example)
-When your print starts, and the Z-axis homes, does it have any issues moving, or does it just bob up and down?
-Did you change the Z-axis travel speed in repsnapper? I suggest something like 70 for the Z axis, 2000+ for X & Y. depending on how you're generating your GCode, it may be that your system is trying to step Z heights
-Have you tried generating GCode for a variety of objects?