New printed parts B7/R3 and other improvements for the MK3  

Re: New printed parts B7/R3 and other improvements for the MK3

Shrug it would seem to be a no brainer and no cost fix if it was done when they assemble the hotend why they have not is a mystery to me not having one when I assembled my kit meant that when the lack of that lock meant that the first time I tried to change filaments on my 3rd print I had a totally plugged printer that took me a morning of disassembled and assembled extruder hot end... and I know I am not the only kit builder that has suffered this unnecessary problem.

Re: New printed parts B7/R3 and other improvements for the MK3

Shrug it would seem to be a no brainer and no cost fix if it was done when they assemble the hotend why they have not is a mystery to me not having one when I assembled my kit meant that when the lack of that lock meant that the first time I tried to change filaments on my 3rd print I had a totally plugged printer that took me a morning of disassembled and assembled extruder hot end... and I know I am not the only kit builder that has suffered this unnecessary problem.

If/when I tear my extruder down I'm going to print Gregsaun's clip...

https://github.com/gregsaun/bear_extruder_and_x_axis/blob/master/printed_parts/stl/common/hotend_collet_clip.stl

Re: New printed parts B7/R3 and other improvements for the MK3

Thank you very much for this post. It was very much needed because I just updated my entire printer to R2 / R3 extruder parts and saw a bunch more R3 parts and thought that I had wasted my time.

For me, one of the most welcome updates was the textile sleeve on the main cable train. The spiral wrap shredded my heater cartridge cable and I had to cover the entire cable sleeve in heat shrink tubing to prevent further damages. Also, another benefit of the textile sleeve is that it makes it easier to get the cable bundle in the old Einsy case. I ran into issues where the spiral wrap wasn't seated in the correct position and when the extruder moved the spiral wrap flexed and the cables started to grind on the Einsy case.

Thanks again for the excellent update and post!

Re: New printed parts B7/R3 and other improvements for the MK3

Could someone post a link (Amazon etc.) with the exact type of textile sleeve Prusa is using now? There are sleeves with velcro, zipper and closed ones. Also with different material, Nylon, PP etc.

Re: New printed parts B7/R3 and other improvements for the MK3

I'm very happy with this one. https://smile.amazon.com/gp/product/B004UHQMYW/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

Re: New printed parts B7/R3 and other improvements for the MK3

Could someone post a link (Amazon etc.) with the exact type of textile sleeve Prusa is using now? There are sleeves with velcro, zipper and closed ones. Also with different material, Nylon, PP etc.

Here's the stuff I bought: https://www.amazon.com/gp/product/B01N2HVKWX/ref=oh_aui_detailpage_o04_s00?ie=UTF8&th=1

It matches the textile sleeve I received in the extruder upgrade bag that came with my MMU 2.0 kit exactly.

Re: New printed parts B7/R3 and other improvements for the MK3

Could someone post a link (Amazon etc.) with the exact type of textile sleeve Prusa is using now? There are sleeves with velcro, zipper and closed ones. Also with different material, Nylon, PP etc.

I went with this one 25 feet for$15 delivered I went with the 3/8 size as I have several places beside my printers to use it I have been using it for the long whip on my big delta for years with no problems and I like the tight package it makes of the wire bundles.
https://www.amazon.com/gp/product/B01MRLJ93K/ref=oh_aui_detailpage_o08_s01?ie=UTF8&psc=1

Re: New printed parts B7/R3 and other improvements for the MK3

If anyone is looking for a user created EINSY case that also includes a new cable entrance for the MMU2.

Suspect Link Removed, by Joan.T

Re: New printed parts B7/R3 and other improvements for the MK3

I've printed the Aug. 3 R3 extruder parts available on the Prusa website and compared them to the parts that I received in the MMU 2.0 kit. The kit parts include the R3 and B7 label but I don't see the B7 label on the parts downloaded from the website. What does the B7 stand for, are there different versions of the R3 and are the Aug 3 parts on the website the latest and greatest?

Re: New printed parts B7/R3 and other improvements for the MK3

I've printed the Aug. 3 R3 extruder parts available on the Prusa website and compared them to the parts that I received in the MMU 2.0 kit. The kit parts include the R3 and B7 label but I don't see the B7 label on the parts downloaded from the website. What does the B7 stand for, are there different versions of the R3 and are the Aug 3 parts on the website the latest and greatest?

You can only get B7 parts directly from Prusa but the parts that are released for at home printing are labeled R3. The reasoning by this is so that if you open a support request and Prusa asks for a picture of your build they can tell if it's an issue due to your print or their print.

Re: New printed parts B7/R3 and other improvements for the MK3

I've printed the Aug. 3 R3 extruder parts available on the Prusa website and compared them to the parts that I received in the MMU 2.0 kit. The kit parts include the R3 and B7 label but I don't see the B7 label on the parts downloaded from the website. What does the B7 stand for, are there different versions of the R3 and are the Aug 3 parts on the website the latest and greatest?

You can only get B7 parts directly from Prusa but the parts that are released for at home printing are labeled R3. The reasoning by this is so that if you open a support request and Prusa asks for a picture of your build they can tell if it's an issue due to your print or their print.

Thank you for explaining that. I read the forums daily to try to stay up on things but some items, like B7/R3, remain a mystery. I have no idea where to go so that I can read about things like this. Is there somewhere on the Prusa website I should be frequenting?

Gary

Re: New printed parts B7/R3 and other improvements for the MK3

I'm aware of the difference between B7/R3 parts, but after reading a few posts I came up with a curious question. Does Prusa add minor changes to the parts without a major revision change?
If updates are made without changing the number is there a list of changes and when they are made?

Re: New printed parts B7/R3 and other improvements for the MK3

...Could you offer a belt tension specifically for each belt that is kg pull and mm deflected...

Hi Eric, great suggestion and I'm collecting ideas about achieving the proper tension for couple of months. However, I would like to achieve this using bundled parts/tools. Giving exact weight and deflection might be a solution for some users, but I need to verify it is applicable to all printers leaving our factory (e.g. the belt properties are the same over time).
---------
I will try your app, but first I need to ask Joe for a new iPhone 😀

Weight is pretty easy. Even with our loudmouthed president, 500g is still 500g and a mm is still a mm. One could, for instance, hang a provided stepper motor from the center of the belt and measure deflection, no "additional tools" required.

There's a million "tuning" apps, anything will work, you will be able to find a free one on any app store. I remember back in the day seeing a similar program for tuning the belt tension on Superchargers for automotive performance.

I've already posted in a few places where I stuffed paper into the body to hold more flow through the cooling fins. If interested let me know and I'll link to it. I've found it helps but have no real data to back it up.

Re: New printed parts B7/R3 and other improvements for the MK3

Forum User RHDreambox has created a fan duct for the MK3 which performs much better for me than the stock nozzle - especially on the back of a print. But also the sides - front is the same.

Prusa Research should reach out to him and adopt his nozzle. IMHO 😉

https://shop.prusa3d.com/forum/hardware-firmware-and-software-help-f64/playing-with-the-air-nozzle-design-t25642.html

Re: New printed parts B7/R3 and other improvements for the MK3

I'm confused as to what revision I have. I was invoiced on 10/23/18, but I see this post is from Nov 1st? When where the new parts included? The assembly hard copy version I have is V3.05 if that is any indication. I was waiting for my MMU to build, but that is three weeks late and I have to get this done over the holidays.

ETA; I see. The parts have numbers on them. I hadn’t cracked open the box yet.

Re: New printed parts B7/R3 and other improvements for the MK3

Regarding OctoPrint

There have been issues using Raspberry Pi Zero W with OctoPrint and the recommended hardware is Pi 3B.
Anyone have a functional update for adding the 3B to the MK3?

Quote from https://octoprint.org/download/
"Recommended hardware: Raspberry Pi 3B.

Please note that the Raspberry Pi Zero W is not recommended since severe performance issues were observed, caused by the WiFi interface when bandwidth is utilized (e.g. the webcam is streamed), negatively impacting printing results. See also here."

Re: New printed parts B7/R3 and other improvements for the MK3

Is this the sleeve you are using?

https://www.techflex.com/general-purpose/f6-woven-wrap?part=F6W0.50BK

Edit : I will probably forget to check back for an answer, if I get one. In case that's what Prusa is using, B&H carries it in both the sizes we need for rather cheap. They're made of polyester, so they're more heat-resistant than the PET ones linked earlier in this thread.

Re: New printed parts B7/R3 and other improvements for the MK3

I bought the revised parts from Prusa and installed them but have not gotten a good print since. I built my MK3 from a kit so I am familiar with the assembly and calibration procedures. I notice that the nozzle is now semi loose in the finned heat sink- I don't remember this before but everything worked fine after assembly so I would not have checked. What could I have messed up? Gene

Postscript- I disassembled the hotend completely and now see that the heatsink screws onto the hotend and was not tight. Hoping that will cure my problem. Thanks Gene

Re: New printed parts B7/R3 and other improvements for the MK3

I haven't received my first printer yet (arrives in a few days) but I already have a Raspberry Pi B+ lying around and I plan to use that and a Pi webcam to run Octoprint. How easy would it be to modify the Mk3 case to house that rather than the Zero?

Re: New printed parts B7/R3 and other improvements for the MK3

Well having already had the drooping effect with the Orange shroud that came with my January 2018 MK3 I am now just printing this upgrade in ABS, just the decrease in heat from 57c to 36c seems to be worth it, however I had great results with the shroud in the link below, I printed it in PETG and 0,20mm and 70 infill, that way if you do not fancy the surgery, this option works with the stock fan at 90 degrees, you do need to use the longer bolts in the spares bag, and the short bolt is fine for the left side.

https://www.thingiverse.com/thing:2869943

Just editing because actually while printing ABS with the above part, it just failed after 2 hours of ABS print, so back to the surgery, however it worked fine for PETG and PLA as obviously lower temp.