Bonded Heat bed for 12"

[rhonal89]

Thanks to you!

Your Prints are looking Great!

[printbus]

...So I could power the Rumba, motors, and extruder from a separate 12V 5amp power supply?

Personally, I'd go for more than 5 amps. Without measuring, I'd assume the input can draw 5 amps, and then it's usually good to have 20-30% margin. The margin is especially important if there's ANY doubt to how much you can trust the rating for the power supply you have. I'd probably see what I could find in the 7.5 amp range or larger. I'd also keep them set to 12V, not 13V, in order to reduce variables I'm adding into the mix.

[rhonal89]

That is a indication of why your layer change with that cubed you shared. Hopefully next update you shared you would have figure out your problem. Also remember the heat bed also warps not just the wood bed.

Well I finally got around to measuring my bed warpage with a dial indicator. I wasn't able to get it all the way to the center of the bed to measure it but I am seeing ~.3 mm change in bed height when the heater kicks on. It isn't a gradual change at all and it cycles up and down as the heater turns on and off.

So if I am printing at .2mm layer height the bed is warping more than a full layer each time the heater kicks on and off. My SSR came in today and I am planning on getting it swapped out tonight or tomorrow so I hope that setting up PID will take care of the problem.

[Chadd]

I replaced the wooden bed a while back with AL so in my instance it is heat bed warpage only.

That is a indication of why your layer change with that cubed you shared. Hopefully next update you shared you would have figure out your problem. Also remember the heat bed also warps not just the wood bed.

[rhonal89]

Here is probably a good fix am also thinking on doing for better prints. Look for a appropriate 12 inch flat heatbed that has it wire solder out of the heatbed not under like the makerfarm I seen some that do this. And clamp it to the aluminum bed and clamp the glass also like make a sandwich some how and use autobed level to level the bed. And counter sink the screws on the aluminium bed so it won't interfere.

I replaced the wooden bed a while back with AL so in my instance it is heat bed warpage only.

[Chadd]

Well I got the Solid state relay hooked up and PID setup for the bed.

So far the results are very good, once up to temp the bed only moves ~0.03 mm vs the .3 mm movement before. It seems like PID is the silver bullet for my Z banding, I think there are multiple ways to fix this as have been mentioned in this thread. One good thing about the PID setup is that the bed temp is rock solid and doesn't move off the setpoint.

Here is the relay that I used.

http://www.amazon.com/Lightobject-ES...id+state+relay

Make sure you get a heatsink for it as well as some thermal paste to put in between the two. Also the relay didn't come with mounting screws so you will need a few screws to mount the relay to the heatsink, mine were 4mm for the heatsink I bought. I can't vouch for the long term reliability of the relay as I have only used it to test and to print the cube for comparison.

Here is a comparison between the prints. From right to left, No Heat, Bang Bang "stock setup", and SSR with PID Heat. To me the result is pretty amazing, even the first layer is much better with no voids in it.

IMG_20150902_140057.jpg

These were all printed with the exact same settings .2mm layer height, 250° extruder, 110° bed in ABS there were no other changes to the printer other than installing the solid state relay and setting up PID on the bed. Even though I have all the parts to replace the threaded rods and couplers I am not in any hurry to do it because of how good the PID results were.

Hope this helps others out there as I can verify that this fixed my Z banding issue.

I have battled this since I got this printer and IMO a SSR and an aluminum plate for the Y axis should be included with the kit along with instructions to setup PID. I know that the Makerfarm is a kit printer and you should expect to do some tinkering with it to get it printing good parts but as long as you assemble and tune the printer correctly you should be able to expect to produce acceptable prints using the parts that came with the kit.

[lakester]

Thx for sharing your research and results Chadd.

When you did the PID calibration..., how did you store the calibration numbers? In the firmware? NVRAM? ???

[rhonal89]

That PID cube looks great. I do the same. Every little help in achieving better print quality. As you say my temp changes often also. Also are you telling me ever since you got the printer with the heatbed on your cube would come out like the middle cube.

[rhonal89]

Also you should open up a new thread and write up a instruction for us all that are looking on doing this. Because it seem cheap and why not do it if it would improve on print quality. Thanks.

[Chadd]

Also you should open up a new thread and write up a instruction for us all that are looking on doing this. Because it seem cheap and why not do it if it would improve on print quality. Thanks.

I will make a separate thread dealing with the PID setup.