Milt's Smartrap V0.4.7 Build

Hi everyone,
Thought I'd share my Smartrap build now that I am finally printing. I sourced everything myself and bought printed parts from Ebay. 48mm steppers, J-head Lite V2, markstephen's J-head Lite mount (rightie) for servo-less leveling, and vinyl tubing for Z-coupler. Printer went together pretty easily with the exception of a few snags... fitting the bowden tube in particular. Biggest problem I've run into is when autoleveling my X-axis stepper sometimes bottoms out on the extruder bearing screw prior to triggering the Z-endstop... not cool. I temporarily fixed it by bumping up the print bed by putting some foam tape on the mounts... still a little too close for comfort.

On to some pictures:

The printer...


The very first print!


Second ever print. Calibration cube.




All in all, I am very very impressed with the printer. This is my first 3d printer and I don't think I could have picked a better one to start with. This forum has been an invaluable resource for little tips and tricks to get everything running smoothly. Thanks!!

Edited 2 time(s). Last edit at 05/05/2014 03:22PM by milt.

Congrats Milt, Those are very nice prints and a very clean Smartrap build. It looks like the new Jhead Lite is performing well too with PLA...

Thanks, madmike8! I haven't had any problems with the J-head Lite V2, although I don't have many hours on it yet. Seems to do great with the PLA I have at 205-210C.

Nice build. When you mention -

Quote

Biggest problem I've run into is when autoleveling my X-axis stepper sometimes bottoms out on the extruder bearing screw prior to triggering the Z-endstop... not cool.

- What size steppers are those? They look kind of long, like real long.

I just measured and if your using 48 mm NEMA 17's then I can see it hitting. Maybe the best way to "fix" that is to make a bit taller Y ends? 2 mm would give you clearance, and 5 mm would give a little extra safety. Is that about what your seeing there? I have the 40 mm type and I'm measuring about 7.7 mm clearance on mine when I home Z. At least that's what my crappy digital calipers are telling me.

How's the J-Head Light mount working for you?

Mark

Congrats!

Another nice build!!
Is that an IKEA cutting board?

BackEMF - Yes a cutting board, but not from Ikea... Had been unused for ages but now it has a good re-purpose.

Markstephen - They are 48mm steppers and are really only too long by 0.5mm or so. Taller Y-ends or a modified J-head mount arm to move the hot end down a couple millimeters would both fix it. Your J-head Lite mount is working wonderfully although there were a few issues getting the M4 nut to fit in between the J-head and the bowden guide. It was a really tight fit which made getting the filament threaded into the J-head really difficult. I'm not sure if the J-head Lite V2 has a little different dimensions then the V1 that you designed the arm for, or if the tolerances of the J-head are not very tight... either way, I got it to work, but a little extra room would be nice. I'll try to take some pictures tonight to better explain the issue.

Another note.... on my calibration print it appears the X and Y axes are printing a little bit long. I don't have calipers yet, but up against a ruler they are closer to 3cm than the 2.5cm they should be. I'm using the shaft adapters, 20lb spectra fishing line, and 102 steps per unit in the firmware. Once I get calipers it'll be easy enough to change the firmware. Anyone else using the shaft adapters and notice this problem?

Okay. Upon close inspection and re-measurement I can say that I was wrong. X and Y axes are nearly spot-on 2.5cm. Z-axis however is about 0.5mm short. Not bad. Could be backlash on the Z-axis nut, low extruder rate, or low hot-end temperature (?). I'll investigate.

the set up the steps per mm, you really need to know the exact diameter of the adapter and the line. Most any cheap digital calipers will get you more than close enough. Once you have the steps calculated, a couple of test prints like a 1 cm cube will tell you how much and in which direction you need to adjust your scale in your slicer to have it come out just right. Anyway, that's what I did and everything is coming out well. If you want to let me know just how much lower you need the J-head to to sit, I'll knock out a custom arm that has the adjusted height and give you a bit more room for the nut. Then once you have the machine calibrated, you can print one out for yourself. To get to that point, you can always take something of known thickness, like a second piece of glass, and use it for your bed probing, add that thickness to your offset and remove the glass for the print, or just print on it till you have the new mounting arm made.

Mark