Which size Prusa?

[TopJimmyCooks]

Over the holidays, I will be able to look at and use my brother's 10" I3V right next to my 8" . I hope I'm wrong but I suspect the 10" is not as well engineered. There's more to enlarging something than just adding an extra 50mm to x, y and z using all the same materials.

for example, I think cheap windowpane glass and the PCB heated bed work well at 200x200mm. I think it may be too flexible/wavy at 250x250. I do know from my brother that the 10" has had more difficulty with bed flatness and Z bed level consistency. Over the larger size i suspect the amplitude of the irregularities is significantly greater. The larger size machines/parts haven't been made as long so there's less end user feedback.

If you don't mind being an early adopter and going somewhat experimental, then by all means go as big as you can afford, it's quite cheap to double the capacity of the printer. I tend to like a mature product and haven't needed to print something big yet, so I'm ok with the 8".

[JimG]

There is a downside to a bigger bed, which is particularly evident if you print ABS. That is, it takes a long time for the bed heater to bring the bed temp up to the 110C or so you will want for ABS.

I have a 10", and I have upgraded the power wiring to my bed to 14AWG. I also am using the heat bed relay, and a 30A power supply. And it takes a long time to get my bed to 110C. In fact, I normally lay cardboard on top of the bed to reduce heat loss in order to speed things up.

The 12" bed is going to require roughly 44% more power to heat it up than the 10".

So I guess the one word of caution I would offer regarding the 12" version is to make sure you plan to use a high capacity power supply, and plan to provide 12AWG or heavier power supply wires for the bed heater.

Jim

[bstag]

So I guess the one word of caution I would offer regarding the 12" version is to make sure you plan to use a high capacity power supply, and plan to provide 12AWG or heavier power supply wires for the bed heater.

The docs tell you to have 12awg for sure. I am running 10awg myself, 8 if have to. I would follow your advice hands down though. Bigger hot bed more time to heat up.

[sniffle]

i honestly don't have that long of a heatup time for either, on the 12"

i've only done a couple prints so far but the bed heats up rather quickly.

I got a cheap off ebay 12v 30A power supply off ebay and am using 12awg wire. so far so good.

i will say that having the 12" bed has already proven useful. I have been able to print the entire heart gear in a single print and it uses the entire 12" width.

[printbus]

i honestly don't have that long of a heatup time for either, on the 12" .

To what bed temp? Issues people have had in the past on the 10-inch printer have been in attempts at hitting 110 degrees.

[sniffle]

Never bothered going that high yet... Hit 60 in about a minute. Im printing pla atm though

[rhonal89]

Great. I order the 12 inch. And I don't want to run into any heating up problem. I bought everything that was recommended in the pdf by Colin.

Never bothered going that high yet... Hit 60 in about a minute. Im printing pla atm though