Heated Bed Flux Mod

[Fabian_Lam]

Hello, this is Fabian and from Hong Kong Kong. I have received my FLUX 3D for almost a month. Very happy with this innovated machine. First of all, this is my second 3D printer. I have spend two weeks to prepare this little MOD project. I have DIY a temperature regulated PCB Heating bed for this little printer. I have googled some information on the heating temperate on the heat bed from material PLA to PVC. After some experiment, the best temperature shall be 45 to 50 degree and the filament wont stick onto the PCB.

Specification:
Temperature can be easily chosen by rotating the knob (40 to 90 degree)
12 V 6 Ampere.

Ingredient:

Arduino UNO R3 Kit x 1
HITACHI HD44780 compatible 20 Char x 4 Row LCD x 1
340 Ampere Electronic Speed Controller (ESC) x 1
EC 12 Rotary Knob x 1
Hexagon shape PCB Heating Bed x 1
Programming knowledge x 1

[mc_ott]

Could you tell us who is your source for the hexagon PCB heating bed?

[fred_dot_u]

I found some 170mm hexagonal beds on eBay, then also located this build project:

Kossel Mini hexagonal heat bed holder by schlotzz

It appears that one should take steps to insulate the heated plate from the majority of the printer, to protect the plastic and electronics.
The plate in the OP photo appears to be larger than 170mm, as the hexagon steel for the Flux Delta is 225mm across the flats and about 260mm across the points. These measurements were done with a minor angle error and are only to be used as approximate reference.

One would ask if such a heated plate modification would allow for ABS or other more exotic filaments.

[Fabian_Lam]

Hi mc_ott You may source the Kossel Rostock headbed. The cost is around US $ 25.

[mc_ott]

Thanks for the heatbed info. I agree, although some airspace, maybe 1/2", under the bed may be enough up to 60C, back insulation is required if you plan to go to 110C for ABS printing (ABS will also require a different head and firmware change).In a previous printer, I used “Foam and Foil Pipe Wrap Insulation Tape” SKU #517666 from Home Depot, which helped speed-up and maintain heating. The issue in Flux will be maintaining surface planarity and how much can the calibration compensate…

[Fabian_Lam]

This is available at Www.taobao.com

Dimension and technical specification attached as below.

[Fabian_Lam]

The thick of the PCB is around 1mm and I think is is the acceptable rang and tolerance of each calibration. The filament is extremely sensitivity to the temperature. Within 1-2 degree Celsius , otherwise it will ruin the print out.

[mikeljo]

Www.taobao.com

Nice.
Will you share us your code and wiring?
Thanks

Bye

[TimSmolen]

I tried to do something similar here:

Unfortunately I cannot get past the calibration step. I’m still working on it but at the moment the head drives into the plate until the motors click. The heated plate sits up less than 1mm higher than the given plate but that seems to be too much. What’s strange is that I can print okay on a 3mm glass circle the same exact size. There must be something else to the calibration.

All the parts I have there are from Amazon. I have designed a nice box for the PWM controller but can’t print out anything flat using the Flux yet. Everything curls up at the edges which is why I want a heated bed.

[mikeljo]

I try a 4mm Glas plate without the original Steel plate. I can calibrate and print. I heated up with an airgun (until i got an Temperature warning )
The calibration takes a VERY long time. But then it prints.
When i put the glas on top the steel i got an obstacle Error.

[Jun_Yan]

i see nuts, is the bed screwed to the plastic underneath?

[TimSmolen]

No, the nuts give a 1.75mm clearance to run the wires out. I need to source thinner wires and thinner nuts perhaps.

[Jun_Yan]

well i think there’s your problem, the bed must rest on the 3 pressure sensor pads else the calibration wont work properly, the pressure sensor pads are there to let the machine know the nozzle has touched on the bed.

[TimSmolen]

That’s what I thought too.

The nuts do rest on the rubber pads. The are only as wide as a nut I guess but they do hit the pads. I will try to engineer something wider than the nuts to see if that helps.

What I wanted to do is rest the heated bed on TOP of the Flux Metal bed but with that combination the print head drives in VERY HARD to the point the the stepper belts pop.

I would like to know more about the pressure switches. Are they really switches like up at top or are they using accelerometers to detect the light taps?

[Jun_Yan]

Flux 3D Printer First Look and Teardown

I got the image from here,

No they’re definitely not a microswitch, possibly something like this
http://www.sensorprod.com/campaign/pressure-sensor-pad/index.php?mcode=gc-pressure
Most probably flux firmware optimizes the sensor to detect a flat and firm pressure across the area.

[TimSmolen]

Thanks for the tip. Now I have an idea on how to move forward.

Think instead of the nuts I will print ( if my Flux is willing ) a 1.5mm cover for the pressure pads that I’ll tap and bolt the heated bed to.

Can PLA be tapped and hold threads okay?

[Jun_Yan]

I think PLA should be tapped fine, but at 1.5mm thickness, probably it’s quite hard to have at least 3 rounds of threads to hold it firm enough.

[Milkdog]

Just an FYI - I updated the title of this from “Say good bye to your Glue Sticks (Flux mod)” to it’s current “Heated Bed Flux Mod” to help make it easier for people to find and understand.