Aluminum bed upgrade?

[CoffeeCup]

I can't seem to find info on reasons to upgrade to an aluminum hot bed. Anybody know? I'm about to purchase a Makerfarm i3v and wondering if I should get the aluminum bed.

[TopJimmyCooks]

Some have experienced problems with the wood bed frame warping with repeated heat cycles while printing ABS. Causes first layer variation within a single print and increases Z banding. If I was buying a new I3v I would definitely get it. I will probably get it for my year old I3v even though it's $38 with shipping. Grrrrrr.

[CoffeeCup]

Okay thanks I plan on printing with ABS regularly so I'll get one.

I'm not sure what type of power supply cord to get for the power supply. Makerfarm recommends getting the wiring kit with the power supply but the wiring kit is sold out. Would a 16/3 power cord like this work? Prime PS010608 8-Feet 16/3 SJTW Replacement Power Supply Cord, Black https://www.amazon.com/dp/B0022NH7G8..._AHHWvb0HZFWCS

[printbus]

Some miscellaneous points in case they are of interest to someone...

I remember reading threads or blogs in the reprap world bemoaining warping and temperature gradient issues in the Prusa style heat beds. I remember hearing how guru nophead had relocated the bed sensing thermistor away from the center of the bed in order to obtain a more realistic average of the bed temperature. Someone had reported they had good luck with "filling in the gap" between the heater and the y-bed at the edges of the heater, leaving some air gap between the rest of the heater area and the y-bed insulator. (I don't remember how this was done - more insulation just along the edge or kapton tape on the sides maybe?) Keeping the print bed covered with another insulator during preheat was found to help bring the entire bed up to the same temperature.

Multiple people had also praised the Panucatt Helios heater as a significant improvement over the basic MK boards.

• 1/8-inch thick specifically intended to minimize warping (MK heaters are 1/16-inch)
• Heat traces are on the print-bed side of the heater, not underneath like on the MK heaters (heat applied to the glass, not air or the insulator)
• Hole through the heat bed to allow the thermistor to be installed touching the glass (or aluminum if that is the print surface) for a more accurate reading
• Self-adhesive fiberglass insulation strips for application on the bottom side of the heater
• Corner mounting holes intended for use with flat-head hardware, eliminating the need for the print glass corners to be cut diagonal or for the glass to sized so it fits inside the corner screw heads. I personally think that the closer the print bed clips are to the corner hardware, the more rigid the print bed will be. Here, corner clips could be installed right up against the hardware.

Unfortunately, Panucatt only shows a 200mm size heater, and for the six months I've been waiting to buy one, they've never been in stock. But the heater might provide some ideas on what others have done. I emailed Panucatt a few months ago about product status, but never heard back. Maybe if they get a bunch of interest in larger ones, etc., they'll have some made up.

FWIW, when I migrated to Smoothieboard, I also noticed smoothieware is considerably different in how temperatures are maintained. Once the print bed is at temperature, Marlin will toggle power on and off every few seconds, leading to the possibility of z-banding if the heater does warp as it heats/cools. Smoothieware uses a PWM to maintain temperature that is usually fast enough that you can't see the status light toggling on and off. So it must be turned on and off at something like 15 times a second (or faster). I'm not suggesting that migrating to Smoothieboard would solve the z-banding issues people have, but maybe someone knows enough about Marlin firmware to see if the update rate could be sped up, reducing the heater cycle times... I know that Marlin has a setting that allows the optional print cooling fan to be driven with a "fast" PWM to eliminate fan whine. Maybe something similar could be done for the print bed heater. Of course, you'd have to have a solid state relay or MOSFET switch for this - a mechanical relay won't cut it. EDIT: Ah, I see Chadd is already headed down this path of a faster heater control loop...

[printbus]

That cord should be fine. Many people just cut the end off an extra computer or similar power cord that they had laying around. The power supplies don't have an on/off switch. If you don't want to unplug the printer to shut it off, a common solution is to plug the printer into a switched outlet strip.

On the aluminum plate, note that the aluminum plate may weigh considerably more than the stock wood one. Worst case, you might need to slow down the acceleration settings for the Y axis in Marlin to keep the Y motor from skipping steps at movement starts/stops. If you have a digital scale that can read grams or fractions of ounces, be sure to weigh both the wood bed and the aluminum bed and report back on what you measure. People have been wondering what these new aluminum beds weigh - an obvious detail that MakerFarm hasn't listed.

[super fly]

That cord should be fine. Many people just cut the end off an extra computer or similar power cord that they had laying around. The power supplies don't have an on/off switch. If you don't want to unplug the printer to shut it off, a common solution is to plug the printer into a switched outlet strip.

On the aluminum plate, note that the aluminum plate may weigh considerably more than the stock wood one. Worst case, you might need to slow down the acceleration settings for the Y axis in Marlin to keep the Y motor from skipping steps at movement starts/stops. If you have a digital scale that can read grams or fractions of ounces, be sure to weigh both the wood bed and the aluminum bed and report back on what you measure. People have been wondering what these new aluminum beds weigh - an obvious detail that MakerFarm hasn't listed.

I was originally going to get an 8". Now I have my eyes on getting a 10" i3v, I figure for the price it will be nice to have the extra space just in case. I have been talking with Colin and doing quite of bit of research. Here is what I got from him on the wood vs aluminum bed weights.

I have the weights for the 12" heat bed mounts, which should be similar to the 10", just lighter.

The 12" aluminum bed is 1lb 11ounces, the 12" wood mount is 1lb 6 ounces so only 5 ounces different. My guess is the 10" difference is less, maybe 4 ounces.

What I'm thinking is 10", E3Dv6 .4mm 1.75mm filament, standard electronics and extruder. I'm not sure on the aluminum bed yet though. That's what led me to this post. Not to hijack the thread but thoughts/comments welcome. Thanks!

[ZorAxe]

One advantage is that if one day you want to upgrade to auto-leveling via proximity sensor, then you have the hot bed always.

[CoffeeCup]

What do you mean you have the hot bed already?

[tsteever]

There are two different parts being discussed it appears. The Aluminum Heat bed and the Aluminum Y-axis which the Heat bed attaches too. To use a proximity sensor you need to have a metal Heat bed (build plate). Most people use glass.

The aluminum Y-axix plate is the one being discussed here I believe. If you got the aluminum Y-axis plate you would still need a metal build plate to use proximity sensors.

For what it is worth, I upgraded to the aluminum plate cause my stock wooden plate was warping very badly. I also use Auto Bed leveling with a micro switch and I find it to be good enough.

[CoffeeCup]

I don't have any way to measure their weight unfortunately