Heated Bed Official Kit Stretched Z

[thirty6 3]

Hi

I have been asked to start this as a new topic and I you can help. UM original now with the official heated bed kit fitted, and i am now getting a bad stretch in the Z direction. If i print a 10mm cube to check dimensions the results are 9.58x 9.46y 12.7z mm.

I updated the firmware through Cura 15.02.1 and used the corrected heated bed option and now have HBK 250000.hex installed.

It printed great as a standard machine, so what i have i done since upgrading??

[ataraxis 51]

Hi! Have you tried to upload the orginal firmware (without heated bed)? If, tell us if the problem persists (it is not related to the firmware then).

[thirty6 3]

Hi Ataraxis

Won't the difference in steps on the old stepper compared to the new stepper mean I wont be able to tell what the old one should be doing without putting the old Z stage back in?

[ataraxis 51]

On the one thread you said:

 

If i print a 10mm cube to check dimensions the results are 9.58x 9.46y 12.7z mm.

 

On the other:

 

Similar thing if I move Z by 10mm in pronteface I get 20mm.

 

I'm a bit confused?!

Edited September 10, 2015 by Guest

[thirty6 3]

Sorry thought the pronteface measurement was a bit vague and i had to swap a stepper motors over as the heat sink was missing. So that is when i printed the 10mm cube so i could do some exact measurements.

[ataraxis 51]

Can you please do the following:

 

• autohome the hotend (prepare -> autohome)
  
• move the printbed 100mm downwards (prepare -> move axis)
  
• measure how much you actually moved (with a pocket rule or sth like that)
  

 

and, can you tell me your current Z-steps/mm? (Ulticontroller: Control -> Motion)

Edited September 11, 2015 by Guest

[thirty6 3]

It moved 130mm by from asking the bed to move 100mm

Current Zsteps/mm: +0533.3

[ataraxis 51]

533.3 is correct for an ultimaker original without the new lead screw (i heard they changed it, but i don't have an heated bed...).

I don't know the new value but i will see if i find it in MARLIN somewhere.

But anyway, it's strange... are you sure that the new firmware is installed?

Edited September 11, 2015 by Guest

[ataraxis 51]

Take a look here:

https://github.com/Ultimaker/Marlin/blob/Marlin_UM_HeatedBedUpgrade/Marlin/Configuration.h

There is one line there that is important:

#define DEFAULT_AXIS_STEPS_PER_UNIT   {78.7402,78.7402,200.0,760*1.1}

Therefore the z-Steps/mm should be 200.0, not 533.3 - right?

Are you sure that the new firmware is installed correct?

I will read the instructions for the heated bed... i'm a bit confused since i don't have it installed

Edited September 11, 2015 by Guest

[ataraxis 51]

Well, I found the problem I guess!

If you upload a new firmware, it will not override the values you stored once in the EEPROM.

Therefore, do the following:

Ultimaker controller: Control -> Restore Failsafe

That command (GCODE: M502) replaces the values in SRAM with the ones in the firmware.

 

// M502 - reverts to the default "factory settings". You still need to store them in EEPROM afterwards if you want to.

 

Now you can store them again in the EEPROM (GCODE: M500):

Ultimaker controller: Control -> Store Memory

B.t.w.: Since the following lines aren't commented out in your firmware, EEPROM is enabled by default

 

#define EEPROM_SETTINGS#define EEPROM_CHITCHAT

 

Edited September 19, 2015 by Guest

[thirty6 3]

Yes you found the fault

You are a hero

[ataraxis 51]

It was my pleasure

[LePaul 331]

I've been following along....so after the Failsafe, does he need to update the firmware again, and it works this time?

I ask because I plan on doing the heated bed upgrade soon

[ataraxis 51]

no failsafe overrides the values in the SRAM with the values in the hex-file (the firmware), store stores them in EEPROM. you cannot change the values in firmware, the correct "factory settings" will always be there if you need them

Edited September 11, 2015 by Guest

[Titus 170]

OMG, I was about to post a question on this. Let me try your solution first I got a funny image of an ultibot coming up.

[Titus 170]

Before fix, one hell of a scary Ultibot:

After fix:

So smooooth! But still some warping, I guess it's the glue/other things that need to be adjusted still.

Edited September 15, 2015 by Guest

[LePaul 331]

I keep seeing issues with heated bed upgrades (like this) which gives me great pause!

But...the heated build plate is tempting because right now, I am prying like crazy to get prints off the blue tape

[ataraxis 51]

 

@Titus: Haha, looks a bit rotten, your Ultibot zombie Was it the same problem?! Btw, i ordered my heated bed today (yeah!)

Edited September 19, 2015 by Guest

[Titus 170]

Same problem yes. I'm guessing it could be because I adjusted Zaccel and Zspeed once, that that got into EEPROM, because I can't imagine all HBK upgrades have this problem

[thirty6 3]

The upgrade is definitely worth it and helps bridges the gap to the UM2. Scrap the glue stick though, 50 / 50 water and PVA and apply with a brush works fantastic.

[LePaul 331]

Well you helped convince me I needed it...just placed the order for the heated bed upgrade.

Is there a brand PVA glue people can suggest? (USA sources please)

[ataraxis 51]

I installed mine last weekend - I like it but

there are also some things they should change...

you cannot fix the backside of the wooden part to the metal plate.

they removed the "hook" for the lower z-endstop

the metal plate is a bit unstable, you can bend it easily if you push the frontside down :/

ah yes the glue stick... what is it good for?

Edited September 26, 2015 by Guest

[Titus 170]

you cannot fix the backside of the wooden part to the metal plate.

 

Actually you can, step 58.

 

they removed the "hook" for the lower z-endstop

 

That is because UMO's home upwards

 

the metal plate is a bit unstable, you can bend it easily if you push the frontside down :/

 

Yeah, same here, but during printing it seems ok actually!

 

ah yes the glue stick... what is it good for?

 

It helps the print stick, although I've heard people swear all kinds of different things work.

 

[ataraxis 51]

Actually you can, step 58.

 

Yes, but that's just the frontside of the wooden enclosure. If i tighten the screws, the backside of the wooden part lifts up a bit and becomes askew and scratches the back panel.

There are two two holes in the metal plate which are unsued, looks like they just "forgot" to cut out holes for the nuts^^

 

That is because UMO's home upwards

 

Yes right, but if you print a very high model... and software endstops aren't enabled...

 

Yeah, same here, but during printing it seems ok actually!

 

Just looks a bit unprofessional

 

It helps the print stick, although I've heard people swear all kinds of different things work.

 

You mean if you don't turn on the heated bed, right?

Edited September 26, 2015 by Guest

[thirty6 3]

Its Elmers PVA that people rave about in the US i think.

Heat the bed to 60deg, brush the 50/50 mix on and let it dry, then print.

Everything sticks and comes off with a high gloss base, XT, PLA, Nylon etc.

Okay you can use the glue stick that comes with the kit but I prefer the brush on method for a cleaner finish. I use it on my UM2, UM 1's and the Printrbot Plus.