Help develop the next MP3DP!?!

Will upgrade hot glue hack to printed part providing strain relief if/when experience print fail due to this janky setup.

Planning to avoid CAN cable wrapping around making an unholy spaghetti mess. Was going to have just point up like Mike’s design here, but add some material to take strain off the microfit connector. Maybe change position slightly to align connector as close as possible with PTFE, as they’re both going into sheathing to help avoid snagging on motion parts.

Accomodating Chameleon might change things for my setup.

Try putting a single strand of filament in with your wires and then putting heat shrink around it. That gave my wires for the E5+ plenty of support while still more than enough flex to not pull on the print head

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Yup, pretty sure it doesn’t matter.

The new one is nothing like that and already has strain relief built in. Just let me know if you think I missed something.

That curved wire guide is interesting…I like that.


Ok awesome! That works out perfect!

Personally don’t mind steppers on the bed assembly, thought it’s pretty cool. However, if steppers can be moved top/bottom to be outside of the heated chamber then that’s nice to have (not critical though).

Either way, solution for avoiding violent bed drop would be good improvement. Slow drop on power outage is ok.

Maybe use cheaper/smaller grade linear rails for Z? Shame there isn’t an opportunity to CNC/print/laser something that brings linear motion closer to $0 ?

you could try something like this…

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MGN9 are about $2 less expensive. I think tho only reason to use a 9 would be to save weight and that is not needed here.

I mean, I bet that is actually pretty reasonable…we could run just one V wheel and let gravity hold it all together…

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Go for it. I am not bothered by the price of the Linear rail, ease of setup and not having it wear out. I dont see that 3d printed part lasting sliding on the extrusion. Im sure it will for a while but nothing like a linear rail. I was just posting for those that wanted a cheaper option.

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I like this idea. The V wheels take a bit of maintenance to keep tensioned, but only a bit. Once dialled in they’re pretty good for a while, and I can replace the wheels themselves several times before I get to the cost of rails. “Bang for the buck” they get high marks.

I actually liked the steppers on the bed plate, it centralized my wiring and the half requirement fkr Z belt seemed like a good thing, less potential stretch. I haven’t had to adjust tension on the V4 like I do with the V3, (though maybe I do need to, and the RRF G29 adjists for it better than the Marlin G29 does on the V3.)


I suspect with the v-wheels you’ll find people who love them and people who hate them, probably largely based on who they ‘just worked’ for and who had issues. I’m one of the ones who had issues and have a machine that’s unusable because it skips steps due to issues with the v-wheels binding. It’s probably solvable with time and effort, but that’s a currency I’m in short supply of.

Ultimately, for me, rails means I’d consider building one, v-wheels means I’d just watch from the sidelines.


I think I am in the same boat with this one. And I am glad Ryan thinks he can give the option for either. That keeps everyone in the game. That option wont always be available but it is nice to see it when it can be.


Yeah, for sure. I think it’s important to be specific during the requirements stage of a project and, for me at least, the rail would be the way to meet the primary requirements with flexibility to use V-wheels as a secondary ‘nice to have’ option. If it can support both without hassle or compromise then that’s great. In my experience, flexibility eventually always comes with compromise, so being careful about defining things up front becomes important. How much of a reduction in performance or is worth keeping the ability to use V-wheels? Is it something where V-wheels can be used but require overhaul of other parts, etc.?

Personally, I’d just say ‘use rails’ and be done with it, but I’m not in a informed enough position to suggest that this is anything other than personal opinion :slight_smile:


Shoot me neither, I feel like I need to buy a couple of those V-wheel things to try out. In Honesty I was just kind of against them, early in my reprap career everything used them and it was just over done. So I need to spend a little R&D money and give them a fair shake. Seeing how they are not still everywhere leads me to believe there is a large downside.

Ive never had a set of V wheels that I felt were truly dialed in. The rails have always seemed so much easier and so much more accurate. Just keep them lubed up and they are good to go. Its probably just like @jono035 and its just what we prefer. I’ve never had a problem with Rails, I have had problems with V wheels. I think you could test till you are blue in the face and its going to be hard to change the mass opinion LOL


Prusa does their strain relief with two pieces that are held together with a zip-tie, so rounded corners and another piece. One of those is also curved.

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Oh what machine? I did some sketches and I can’t find a way to make it work well

Okay, here is the zip-tie thing - This step and the next few in the assembly guide: 4. Z-axis assembly | Prusa Knowledge Base and here is the curved one: 4. Z-axis assembly | Prusa Knowledge Base

Okay I am looking at it closer, Z stepper on top is not going to work well. Bottom it is, that does mean we can reuse the Front tensioner assembly for the top, so smaller BOM!

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Any chance that’s updated in the cad?

Yup I save all the time.