24volt power
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Another thing to consider besides just the motors is the heated build platform. Going from a 12v to a 24v heated bed requires significantly smaller wiring and is less stressful on the power supply, interconnects, PCB traces, and MOSFETs.
I went with a 24-volt setup on my 3rd printer build and I can tell you, from now on all of my future builds will be 24-volts as well.
Wait till you switch over to a silicon AC heated bed with a SSR. You will throw away your 24V setup in no time. Some heated beds have 800 watts of pure heating power!!
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Wait till you switch over to a silicon AC heated bed with a SSR. You will throw away your 24V setup in no time. Some heated beds have 800 watts of pure heating power!!
Er…...I have AC heated bed but no intention of throwing away my 24V setup - why would I want too? Also, bed heater should be carefully matched to the bed size and to some extent the thickness of the plate and whether it is insulated or not. Too big a heater will be difficult to control if not downright dangerous.
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Wait till you switch over to a silicon AC heated bed with a SSR. You will throw away your 24V setup in no time. Some heated beds have 800 watts of pure heating power!!
Er…...I have AC heated bed but no intention of throwing away my 24V setup - why would I want too? Also, bed heater should be carefully matched to the bed size and to some extent the thickness of the plate and whether it is insulated or not. Too big a heater will be difficult to control if not downright dangerous.
Very much agree here I use the 0.5W/cm3 rule of thumb hence to 620mm diam one I have just ordered is 1500W at 240V
this is going on a 650mm diam bed of 8mm Ecocast (Not sure that 6mm wouldn't sag in the middle under heat) If someone could convince me it will stay stable then I would rather use 6mm.
Doug
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Hi Doug,
That's a big bed! I can't say that 6mm x 650mm dia won't sag but if you can possibly use it instead of 8mm I'd strongly advise it. Maybe you could fit a brace under the bed to support it? I went for 10mm on my 400 square bed - big mistake. When you first start to heat it, there is a huge difference in temperature between the underside and the top. If the temperature sensor is fitted between the heat pad and the aluminium, it'll control the temperature at that junction which bears little resemblance to the temperature at the top of the plate until the heat actually "percolates" through. I drilled a 3mm hole, about 40mm deep into the edge of the plate and put the sensor there which helped but it's not ideal. The other thing is that it takes forever to cool down - not an issue if you have a removable surface such as glass but otherwise it's like 45 minutes or more to drop from 50 deg C to just above ambient.
On the other hand, the extra mass does help to keep the printer stable and damp out any vibrations (but a paving slab on the base would probably work better).
Ian
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Ian
I Know what you mean my current bed is 400x400 (Or was till I chopped the corners of for the Delta and that is 6mm which is fine.
If you remember we spoke about the temp issue and I pointed out that I drilled my plate to put the thermister closer to the top surface tho out on the periphery of the bed the heater I have ordered I have asked for there to be a 20mm diam hole at the centre of iut to allow me to get the Thermister as close to the top of the center of the bed as I can (I have some that are mounted in a M3 Brass carrier so I will drill and tap the center of the bed to take one of them.
Dont think it would be easy or even possible to brace the center without beefing up the whole bottom section especially taking into account the silicon pad?
Doug
