Solidoodle 3 Mods, and issues. (Page 5 of 9)

Well. Pretty damn FAST! Holy heat. This is 3/8" cast plate mind you, and it heated it up past where i needed it to be in 2 minutes. Before it took 30 minutes with the stock pad! I used my last known good configuration of 112C, to get an indicated 95C. This seemed to be dialed in perfect previously. I had to reduce those temps to get my bed temp back down to 95C as you can see from the graph. Now my temps are much closer. Once the plate seemed that it was heat soaked i set it to 98C and it got right around 95C indicated. When i mounted the temp indicated, instead of copy catting what solidoodle did (drill a hole a shove the little bulb in it). I did drill a hole, but filled it with 3M thermal paste which is non conductive, and transfers heat extremely well. Before it was in a mini air pocket, which doesn't work all that great for close, readings and reduces response time. Great thing is i can unplug the unit, and the bed still remians HOTT for a long while. This should be a much more stable temp heat bed.

My graph does indicate a pattern of hitting temp, and instantly kicking the heat back on and letting it drop back to temp (see graph attached). Can that be changed in the PID settings?

See manual tuning.
http://en.wikipedia.org/wiki/PID_controller

I did properly ground the unit, and check continuity all over the machine to ground. I suggest if you do this project, don't skimp out on the 3 prong power plug, and the $3 dollar ground bar. It can save your life. If your not comfortable with electronics/electricity, get a friend who can help.

Overall success though! Tomorrow i will hook up the chamber heater and pid controller. More pid fun... haha

Congratulations get it tuned in and your temps should be nice and level.

I think that is a great idea. Would be bad to come back to a pile of molten plastic, or a fire.

http://www.radioshack.com/product/index … ue=Thermal

Would something like this be appropriate to use? How would i go about installing it. Running 120V through an open fuse, attached directly to my aluminum plate sounds like a risk if not done properly.

p 174.56
i 21.65
d 351.78

ok used these settings in my eprom. I wasn't sure if i needed a third party program to update that, or if i could just go into repetier and update.

Edit:
Ahh so i run G code and return my values. Ok will do, i have to let my bed cool now.. I see it said run with the "nozzle" cold, but doesn't mention run with the bed cold, but i think its an implied thing to do, so letting this cool down now, and well compare values.

http://reprap.org/wiki/PID_Tuning

thanks everyone!!

Also on that thermal fuse, don't they make something more so like a breaker i can reset instead?

You will need to re do that, because that is for your extruder.

For the bed, you must update and upload the *firmware*.
As per previous message, its in wardjr's thread quite explicitly how to do the bed pid.

M303 S195 C5 <- you do this for the *extruder* and put the results into EEPROM
M303 E-1 S95 C8 <- You do this for the *bed* and put the results into configuration.h as specified in the other thread. Its all there for you.

No wonder why the graph looked the same for the heat bed... hahah! thanks for the catch!

Scratch that, i found the bottom  header it was hiding!

A simple and cheap safety is a coffee pot switch although this will be self resetting... but you could wire a loud buzzer across it so you will know when it trips.

Would i just attach that to the build plate and than wire my 120V inline with it essentially?

Well i went ahead and wired up my PID controlled chamber heater. I will eventually mount it below the unit and cut a vent hole for it, but until than, i don't plan on building any really tall models just yet so i put it horizontally under the build platform.

works REALLY well. Set it to 28C, (room temp was 19C). Watched the temp climb, and shut off. I was monitoring the extruder temp (extruder was off). Eventually the extruder temp was showing a solid 28C and had flat lined alone with my build chamber temp. I only referenced the extruder temp to see if i was close to what the new controller was reporting, and it appears that i am very close. Once the build plate was turned on the temp rose and stabilized to around 37c. Anything higher than 28C the heater doesnt kick on. I'm thinking of installing a little 120V fan also and using i to cool down the chamber if it "overheats".

Because the bed is NOT stored in eeprom, it is only from firmware regardless of the referenced wiki - I do do Marlin dev work remember You are wasting your time until you edit configuration.h as already advised.