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Isaac Mendel build

Posted by jkelso 
Re: Isaac Mendel build
September 15, 2010 08:02PM
I'm looking over the wiki now on attaching the nichrome wire to the extruder nozzle with fire cement. I have the holes notched in the copper tube but I didn't make a tab to hold the tube on there, it seems like it should hold on with Kapton tape but I could be wrong. Also, it says I should hold the wires in place with blu tack. I researched blu tack and it is an adhesive but I'm wondering if this is something temporary to hold the wires or if I need to purchase blu tack somewhere. Is the blu tack going to be used as a permanent insulator for these wires?
Re: Isaac Mendel build
September 15, 2010 08:31PM
I found a very informative bit on the wiki "welding your own thermocouple". I'm not going to weld mine, it was welded at the end but I accidentally clipped it off. I was worried it was important, but I found out it isn't and that I can just twist it together. I'm back again from home depot the the blu stick and this time there were no complications other than one guy who chewed my ear off for ten minutes the other day and then didn't return a wave from across the aisle. What is with these guys?

Re: Isaac Mendel build
September 15, 2010 08:37PM
Just checked my setup. There's a 2-pin header on the extruder controller and an 8-pin header on the motherboard. Connect the 2-pin header to any of the four pairs of pins on the 8-pin header. The extra pairs are for additional extruder controllers (it's a shared bus).

For the extruder stepper, connect the SDA and SCL pins on the motherboard to the step and direction pins (part of the 10-pin connector) on the stepper driver. Also connect the enable input (also part of the 10-pin connector) to ground. I don't remember whether SDA is step or SCL is step.
Re: Isaac Mendel build
September 15, 2010 09:14PM
thanks. I still have to get a picture of what all those terminals are along the top. It says -12v+ on two, and -c4, -b4, and -a4 on the remaining 6. I understand that the stepper goes to the other terminal with 4 screws but these other ones I'm not sure still. I decided to make a new copper tubing jacket with a tap and a small screw to hold it onto the plastic barrier.

Re: Isaac Mendel build
September 15, 2010 09:27PM
If I run the gnd from the thermocouple sensor to the 12v - and the 5v+ lead to the 12v+ then I have one signal wire left. I suppose it goes to the 2 pin temp leads on the extruder controller but I'm not sure on it.

Edited 1 time(s). Last edit at 09/15/2010 09:28PM by jkelso.
Re: Isaac Mendel build
September 15, 2010 10:11PM
I decided to crimp some wires onto the ends of the nichrome wire before cementing. I found these crimp connectors on hand. For once I didn't have to run out in the middle of something for more supplies. I checked the ohms and it's still at 5.5.

Re: Isaac Mendel build
September 15, 2010 10:43PM
I secured one end of the wire on the side with blu stick, put some cement on the nozzle, dried it with the blow dryer for a few minutes, then wrapped the wire halfway down. Now I'm going to add more cement, dry some more, and get that other wire wrapped around back up to the top.
Re: Isaac Mendel build
September 15, 2010 11:05PM
now I've got the wire coiled back up to the top over the first layer of cement and the wire secured to the side with blu stick. The copper jacket fits around the two wires. I put more cement over it and dried it with the blower. I also wrapped the thermo sensor wire around the bottom end of the nozzle and I'm getting ready to put more cement and test it and put the copper jacket over it with kapton tape over that.

Re: Isaac Mendel build
September 15, 2010 11:38PM
I put on the copper jacket and secured it to the plastic the the small screw. The ohms measure at 4.7 so I put some more cement in the tube and taped it all up. Do I need to use jb weld to attach it into the wade's extruder or will it be ok with a screw in the side through the small hole to secure it?

Re: Isaac Mendel build
September 16, 2010 12:22AM
I attached the extruder to the bearing rods and got everything rolling back and forth nice and smooth. This is starting to look pretty fierce. I think I'll call this unit "Ra".
Re: Isaac Mendel build
September 16, 2010 09:26AM
Getting close.... smiling smiley
Re: Isaac Mendel build
September 16, 2010 07:12PM
Today I went down to school where I'm taking the last of the CAD classes offered there to show my teacher my work. He was very impressed with it and said that the one that school was thinking about getting was $23,000. Then, another stranger came up to ask about it too. I believe that others in the class pretended not to notice. The power of transmogrification is nearly mine. I'm limited by the fact that I don't have all the connectors in hand yet to complete this, but I still have time to complete some last details by the time my package arrives. I drilled out a new hole in an opto end stop today and aligned it pretty close to what I'll need after the bed springs are in.
Re: Isaac Mendel build
September 17, 2010 01:20AM
Putting that last opto stop on the extruder wasn't easy. I tried removing one bolt on the corner and sandwiching in the opto stop but the stop was too loose and if I tightened the bolt too much the extruder wouldn't slide on the x axis. So I had to take apart the extruder and tighten another nut underneath the first piece of plastic, then another nut at the bottom of the extruder. These bolts in this area are difficult to reach and the extruder isn't easy to take off and put back on. But finally, after struggling for a few hours I have it all back together and working perfectly.

Re: Isaac Mendel build
September 17, 2010 10:24PM
Tonight I've rearranged the thermosensor board to another spot, connected the wires from the sensor and from the nichrome wire to the 12v - and + terminal on the top. I connected the driver motors to the abcd terminals on the side. I took some time to zip tie everything so that the extruder has just enough slack to complete the travel. I also connected the Y axis motor to the driver board and tested it out, the stepper worked fine.
Re: Isaac Mendel build
September 18, 2010 11:32AM
Preparing to put the belts on, I'm adjusting the position of the Y motor mount and the corresponding pulley mount on the other side of the frame. The platform was having trouble clearing the frame because of the L shaped "purge plate" being too low so I took it back off and put 3 washers in between the bottom of each bolt between the two pieces of wood.

Re: Isaac Mendel build
September 18, 2010 12:50PM
It took me a minute to figure out how that happened since the purge plate normally slides under the threaded rod. It looks like you mounted your Y smooth rod on top of your threaded rod. The cad drawings have the Y smooth rod mounted under the threaded rod. (Did Brett point you to the CAD files? They're a good reference until our documentation is complete.) This will allow the purge plate to slide under like intended.

The higher position will lead to one more issue. The belt normally clamps on top on the Y carriage to align properly with the bearings on the Y motor and Y idler. You can try clamping the belt below, but its alignment will be slightly off since the Y carriage is thinner than the rod diameter.
Re: Isaac Mendel build
September 18, 2010 01:49PM
Now that I look closely at the picture I see you are right, the bearing rods go on the bottom. Looks like I'll be taking the platform off again.

Re: Isaac Mendel build
September 18, 2010 02:15PM
After ratcheting one or two of these off, I realized that it's much easier to put the bit into a hand drill for them.

Re: Isaac Mendel build
September 18, 2010 03:49PM
I ended up having to insert another bar clamp between the board that holds my driver boards and the frame so that the platform can clear the bolts underneath. I bolted the Y axis underneath the plastic parts rather than on top. I think it's time we demonstrated the full power of this station.

Re: Isaac Mendel build
September 18, 2010 06:58PM
I got the last needed parts to finish from All Electronics today, it shipped pretty quick. Also, I got a bare reprap motherboard from Tom Herbert on ebay. I'll probably start putting that together later when I finish up on this.

Re: Isaac Mendel build
September 18, 2010 10:53PM
I found a wiki how to page for tech zone remix that I wasn't seeing before. It should clear up a lot of questions.

Edited 3 time(s). Last edit at 09/19/2010 01:16AM by jkelso.
Re: Isaac Mendel build
September 19, 2010 02:10AM
Been following this daily. Keep up the great posts. Cant wait to see it print
Re: Isaac Mendel build
September 19, 2010 09:10AM
Thanks, this is the last major hurdle in getting this to work. The extruder board is such a mystery and I've been trying to study the "tech zone remix" page on the wiki and pour through old forum posts for clues to how it's hooked up. I went to youtube and watched all the videos I could but the users never explain anything and it's always a shot from far enough away that you can't see the connections. It wasn't until late last night that I stumbled upon another search result for "tech zone remix how to" which I haven't delved into yet. I think that the answers can be found here but I'm still trying to wrap my head around why they are so difficult to find. I think that there is a certain amount of "why would I want anyone else to have this technology, especially people too stupid to figure it out?" that comes into play, even from some of the parts vendors. Is this a puzzle, a challenge, a charity, an engineer's club, or a business? I'm not sure I've figured that out yet either.
Re: Isaac Mendel build
September 19, 2010 11:13AM
I did find one possible workaround to the electronics problem.

Re: Isaac Mendel build
September 19, 2010 05:26PM
After a nap, I woke up and decided to kick around the archives again. My eyes were getting tired. I took a fresh start and went to the 2nd "tech zone" search result from the wiki, the "how to" page. Much of these pages are devoted to the author telling of their workload and explaining that this is why everything is so late and discombobulated. I skipped past all the irrelevant stuff down to where if says something about kimberly needing a break and going crosseyed and figured out I need the reprap firmware to start with. I'm running the machine as EXPERIMENTAL cupcake cnc 2.4 in replicator G. So, after clicking through some more links to another page I finally find the reprap console download page that I looked for one night weeks ago but could not easily find.
Re: Isaac Mendel build
September 19, 2010 06:28PM
After downloading the software I didn't see any exe files in any of the folders so I went back to the archive and realized I also need to download Java. I've worked with Java a little and I figured that as soon as I installed java it would run the software and I was right. Now I think things are feeling more positive and I'm back on the right path.

Re: Isaac Mendel build
September 19, 2010 08:35PM
"In your download directory there is a distribution configuration file called configuration.h.dist. Copy that file to a new file called configuration.h"
more accurately, in the zip folder>mendel folder>firmware folder>fiveDgcode folder> there are 2 folders one for extruder and one that says fivedgcode interpreter. Both of these folders have a configuration.h.dist file in them so I went ahead and copied both files each to their folder and renamed the copy configuration.h
Re: Isaac Mendel build
September 19, 2010 09:49PM
Ok I got to the step where I'm supposed to open the fived_gcode_interpreter file in the arduino software but it says in the wiki that I'm supposed to see a tab called configuration.h there is no tab for this nor is there one for the original file before I copied it. I tried opening the file with notepad but it's very dense with code and hard to read this way. Is there something I'm missing or not seeing here? I may try uploading this as is and see what happens, it beats sitting there wondering about it.
Re: Isaac Mendel build
September 19, 2010 10:14PM
My first attempt at compiling the code untouched was unsuccessful. I got an error message that is looking for a character "response size" hmmm
Re: Isaac Mendel build
September 20, 2010 02:57AM
Try opening that file with Notepad++ ( [notepad-plus-plus.org] ) or with wordpad. The blocks you see should be new-line characters, but notepad doesn't recognize them. That's why the file looks so dense.

my blog: [reprap.tman.be]
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