So I ordered a +Geeetech +ultimaker 1.5.7 boar.d on ebay. I must have been sleepy when I read the specs because I also ordered a 16.7a 24v power supply. I have done some research and have come up with limited documentation on running this board on 24v. I found some information on the 1.5.3 and 1.5.4 also the never released 1.5.6. Basically All electronics on these boards are said to be able to run on 24v+ but the linear power regulator gets hot.Some add a heatsink others switched for a switching regulator that just solders in. I was hoping someone with experience in this could loan me a little knowledge in the right way to do this.
@John_Ridley LM7812 12V regulator http://www.cdil.com/datasheets/lm7812.pdf this is the component in question. The previous boards appear to have caps rated for 60v and all other components rated for well over 24v. I just want to do this right. And since its its from china I plan to “walk” the board to ensure that all of the components are the same as the github and rated above 24v. Some say this is a suitable replacement: http://docs-europe.electrocomponents.com/webdocs/0fb7/0900766b80fb7063.pdf and is a more elegant and efficient solution than just slapping a heat sink to it.
The Pololus can take 24v just fine. In fact you can usually lower motor current and keep your torque with everything running cooler. For the voltage regulator, would something like this work? http://www.gravitech.us/312v1aswvore.html
Just get a cheap PC power supply. More than enough amperage, and supplise 3.3, 5v, and 12v. I use them as bench top power supplies for all kinds of things. The power out of them is clean enough for many things.
@Daniel_Joyce thanks but I’ve been down the ATX power supply road. I want faster bed heat times. I use custom self made nichrome kapton and aluminum plates. 12v on a 47a supply takes nearly 1hr for 110c ( its 3mm glass on 6mm alu 304mm x 304mm). with 24v it would be less than 15 minutes. For high amperage at 12v for cheap I buy dell server supplies for under $14 US to my door I want to get away from the 12v ramps I’ve been using. My newest printer build has a lot in common with the Ultimaker so I want to try the Ultimaker board. I would like to run it off a single power supply and preferably 24v
@korpx I coated the bottom of the plate with kapton. I then kapton taped the nichrome elements to the bottom of the plate. The aluminum is for heat spreading. And finally the glass is on top. In my pictures, I believe there is a picture of my plate. Originally I used 4 14awg nichrome in 2 11in strips and 2 10in strips linked with stripped copper wire and butt end connectors. The copper carries the heat without adding much resistance. I have ordered some 24awg nichrome from http://www.jacobs-online.biz using their calculator I found the optimum layout for 24v and ordered 100ft for like $10us
I guess 6mm aluminium + glass will take some time to heat up yeah. If you use a suitable adhesive on the bed you shouldn’t have to go to 110C, at least not for ABS. I use water soluble glue stick on 70C which it takes 4 minutes to reach with 12V/ATX. Standard PCB heater with 3mm mirror glass on top. With a 6mm brim I haven’t had problems with adhesion yet.
@korpx I use abs juice. It is kinda of a multipurpose solution I use. I use a make up sponge with it for acetone smoothing. I use it as an adhesive for prints, and it serves 2 purposes, I use a cotton ball to apply and scrub off the old abs layer and it removes oils.
We tried it on a thin sheet of aluminum as a heat spreader. The aluminum bowed badly and reached 120C in about a minute. It was actually a case of the bed heating faster than the hotend, which was weird. It would require PID_BED enabled in the firmware.
