Heated Bed Upgrade - Guide with Pics/Comparisons/STLs (Page 2 of 4)

Wouldn't 1oz boards have lower crossectional area per trace, and therefore higher resistance?

What is probably triggering the shutdown is short-circuit protection on your power supply, seeing the large spike. Or you are unlucky and just have a particularly unstable 12V power supply. Furthermore, you need to derate the 12V amp rating substantially, since it tends to not work reliably anywhere above 70% of the rated current.   That puts you at 14A, much less leeway than your initial ratings would suggest.

I can confirm that I have a computer power supply 12V that I run at roughly 16A for my electric bike charger, and some server power supplies I've reliably pulled 30A+ from.  So as a concept, it does work.

You could also add an inductor on PCBheater inputs, to reduce the current spike when it's turned on, but the right value might be kinda high, because the arduino PWMs at such a low frequency, and because I have no idea how sensitive the short circuit protection on these power supplies are.

I would like to see some more pics of the Arduino modification. I am a bit confused on what to solder and where to as far as the bottom side jumping. The solder points seem a bit different in photos two and three of the board modification.
Also, what is the best way to get the old z screw off of the motor?

You could also make an improvised "Gear Puller".

Take a piece of flat metal stock about an inch wide, and dremel, nibble, hacksaw or drill (probably in that order of effort) a 5mm wide (No Wider!!) slot down it to *just past* halfway point.

Get two bolts of probably M6 or so variety, and tap two holes either side of the grove so that with the flat metal bar slotted under the lead screw and holding (but not gripping) the motor shaft, you can bolt them down against the motor face.  If you dont have taps, you can clear drill the holes and use two wingnuts attached under the metal plate.

You now simply *evenly* do up the bolts... the metal plate will cleanly and for the most part equally apply pressure directly upwards on the lead screw, and eventually, you will simply have it pop straight off. Just be sure to do it evenly.. one turn left side, one turn right side, etc etc..

The same principle as a pulley-puller, but since we cant screw against the top of the leadscrew, simply invert it, use two bolts, and screw against the motor casing (which will easily withstand the force needed to pull the screw off).

Getting it back on is another story... you basically need a dedicated Arbor Press, or at a minimum, a quality drill press...

Ya, I think I saw your post. It is always nice to see what others have done.

Lawsy, did you put the new bed screw terminal in different holes? I just went to change mine to the same screw terminal you linked to and the pins are spaced out further.

I bought the 5.08mm linked to in the OP. I ended up putting it in the first and third holes. That should still work, right?

http://www.jaycar.com.au/productView.asp?ID=HM3130

The stock connector on the board of my SD3 had pins where I labeled 2 & 3. I'm not very experienced with soldering boards, but it appears that 1/2 are -V and 3/4 are 12V. So I used 1/3 in place of 2/3.

200*200mm QU-BD with 10*10 tempered glass. I used Smitty505000's STLs, but had to cut out the area where the bulky section of the bed is because it was too shallow and wouldn't sit flush. The thermistor wires for the QU-BD were a tad too short, so if you pick one up add a couple inches of your own wire before adding the connector.

I have to re-solder my thermistor wire and buy some smaller gauge wire for the Dell power supply(10 gauge pictured), but it came out well. It's nice to be able to actually watch the bed temp go up without having to leave it sit. The 10*10 glass plate barely fits. I had to increase the length of the clips to fit it, but it is clearing the X-motor and wasn't too difficult to level with homing. Not bad for $2 a plate...I haven't tried extending the print area yet, below is my first test print in progress.

Urg... Mine isn't going so well! Repiter said temp was 80c but lazer thermomiter said 110C as i turned it off i thought i heard a bit of a click... Turns out it was the glass.

Presumably this is what the PID tuning stops?

2n2r5... Urg how do I go about that? I read back over the earlier section of this post but to be honest the firmware bit has gone right over my head.

I presume I have to upgrade the firmware prior to running the PID. I really need walked through this stp by step because its all gobbly gook to me a the moment!

Where do i get lawsys firmware from?

Cheers

Updated 14-8-12 marlin version 1 by lawsy is my version.

Cheers buddy, really appreciate it!