Duet3D announces new tool board at FormNext

fcwilt

@jay_s_uk said in Duet3D announces new tool board at FormNext:

@fcwilt the RRF-36 is shaped to mount on the rear of a nema 14

There must be more to that. A NEMA 14 is square. The RRF-36 is not.

Frederick

jay_s_uk

@fcwilt round nema 14's aren't square... https://www.omc-stepperonline.com/round-nema-14-bipolar-0-9deg-8ncm-11-33oz-in-0-65a-36x20mm-4-wires-14hr08-0654s
they're now also the most popular type of motor to use on an extruder

fcwilt

@jay_s_uk

Well now it makes some sense.

Thanks.

Frederick

A Former User

@fcwilt Let me guess, back in math class you were the one to yell out Pie aint square, pie are round . Right?

fcwilt

@KenW

No, not that I recall.

It just seems to me that they made that shape to fit onto/into something else where that particular shape was well suited.

I doubt they picked that shape for artistic reasons.

Frederick

A Former User

@fcwilt Southern humor does not translate well I take it. The complete version of that one is.
Pie aint square. pie are round, cornbread are square.

droftarts

@fcwilt I don't know what the design parameters of the board, but you can guess from these pictures:
alt text
It doesn't fit behind the motor, it fits on the side, but it is the same width and height as the motor and extruder. This picture makes it look big, but that's a NEMA 14 round stepper, it really is tiny and light, even compared to a Hemera. Connections are forward and back, rather than up or down, and the mounting is very specific to the Roto extruder (it has the same spaced mounting holes on the other side of the extruder). Connectors are the standard ones E3D fit to their heaters, fans and thermistors, so they just plug straight in. Only the CAN connector exits from the top. There's a hot end fan on the other side, and I don't know where a part fan would fit on. It looks like the board could have been square, but for the top mounting hole. Probably the first Duet board with rounded corners - someone asked at Formnext why we didn't put rounded edges on our boards, and I pointed them towards @T3P3Tony!

Ian

jay_s_uk

@droftarts and the CAN connector is the same one that's been adopted by Mellow and BTT (XT30 2+2)

Surgikill

Well, looks like the roto is available for purchase through filastruder. Going to wait to purchase until the documentation is available.

Surgikill

Eh, I just found some basic documentation and max ambient printing temp is 40C. Think I'm going to have to pass on this extruder.

o_lampe

@Surgikill said in Duet3D announces new tool board at FormNext:

max ambient printing temp is 40C

Can you quote this or add a link for us?
I wonder if that's related to the 3d printed heatsink? Maybe it's thermal conductivity is too low.
Funny enough they dont conduct heat from the stepper, but added a thermal barrier between.

jay_s_uk

@o_lampe must be this bit he's quoting
https://beta.e3d-online.com/pages/help-centre-roto#:~:text=Performance Characteristics,temperature%3A 40°C

o_lampe

I've checked some papers and the conductivity of SLM printed aluminum-alloy is in the ballpark of conventional aluminum alloy material

Pure aluminium: 237 W/mK
SLM printed AlSi10Mg: 130-190 W/mK
Other Aluminium alloys vary from ~90-150 W/mK

So, if it's not the SLM-heatsink it must be poor design choices regarding airflow?

gloomyandy

@o_lampe The max service operating temperature (not 100% sure what that means) for the motor is listed as only 50C so perhaps the max overall ambient temperature is related to that?

gloomyandy

@o_lampe I guess the best thing to do is to ask e3d what the basis is for that 40C limit.

Surgikill

@jay_s_uk yes, that is where I got the info. I know in the interview they said this heatssink is the most efficienct they have ever designed, going as far to say they printed pla at 40c ambient temp. I'm not sure if this is why it's rated at 40c, or if it's the plastic planetary gears.

elmoret

Based on how E3D rates things, 40C is the “PLA without jamming” temperature

Surgikill

@elmoret if that's the case then it's a different story, but if the motor is only rated to 50c then I don't see it going over that, which is still pretty low.

gnydick

@edsped I've found even for one tool head, I'd trade the cost for the convenience of not having to run 19 conductors for each tool.

heater: 2
thermistor: 2
fan: 3
fan: 4
stepper: 4
filament sensor/(un)load trigger button: 4

Surgikill

Anybody have any idea why the motor on the roto is only rated for 50C? Looking at the 36mm LDO pancake stepper, it is rated at 180C. Not sure how accurate that is, but it is a gulf between the roto and the LDO, and they look like the same motor.