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The Bed

A project log for Printrbot 'SuperSize Me" Mod

Transforming the humble 150x150x150mm stock print bed of a printrbot simple metal to a whopping 500x500x150mm

ken.doken.do 01/22/2016 at 20:484 Comments

i just picked up my new printer bed! As I wrote in a previous log, I decided to keep the option for a y-axis extension open and had my bed water jet cut to accommodate a roughly 10 inch y-axis from the 6 inch limit of the original bed.

Weight may be an issue. This 6061 aluminum bed weighs 2007 g. Supporting this amount of weight causes a slight bend in the x-axis rods. When the bearings are locked down, they will be more effective at keeping the rails straight. I will continue to assemble as is and see what happens to prints.

To lighten up the print bed, the bottom side could be milled out to the size of the PCB heaters. This would not only cut the weight of the bed almost in half, but would also reduce the thermal mass enabling faster heating and cooling of the print bed.

If reducing the weight does not solve the rod bending issue, a move to 10 mm rods may be in order.

Another consideration with more weight is the drive system: can the drive system handle it? Will belt slippage become an issue? Overheating of the stepper motor?

Tune in next time and find out!

Discussions

Adam Tolley wrote 02/19/2016 at 16:26 point

Hmm, good to know, thanks. 

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ken.do wrote 02/19/2016 at 01:39 point

A solution for you might be to use a small piece of aluminum duct tape to bridge the holes where the sensor misses.

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ken.do wrote 02/19/2016 at 01:34 point

The holes are there as a thermal break. My rail ends are PLA and don't like heat much. In the printrbot version, they act as thermal breaks so the heat doesn't move through and radiate out of the aluminum 'wings' I believe.

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Adam Tolley wrote 02/19/2016 at 01:31 point

Why the holes in the end? I hate the holes in my heated bed, the probe always misses due to them and I have to trim my build envelope as a result.  

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