Some updates to ,

Some updates to #zsplat, photos also show a new QR build (called #RickDangerous cauz i drilled into my finger when doing the QR holes in my kitchen … … …). +MakerGal #GSlot profiles and wheels

h4v phun.

Any reason for not using the alu vertical members as linear guides? You might be interested in #Miltykoss build by #AlohaMilton for some linear guide ideas. I believe his approach should also be tried on corexy printers. Anyway congrats for the very clean build.

Also I would be very interested in a presentation of your machine while printing, nothing fancy just some food for the mind for us the rest procastinators to have something to feed our desire to finish building our own machines :smiley: … if that would be on youtube would be great, G+ doesn’t open videos for me for some reason… the loading wheel keeps going forever.

@Florian_Ford thanks for the tip. could be done as well but i can’t see a direct benefit. my setup is more or less invariant to small changes in the cross bar length. thus, might be easier to setup. i have however another idea which coincidentally is even more similar to your link.

i hope you manage to finish your build soon. i build 2 corexy’s before but having done the QR i find it superior in almost every respect (relative to my own custom builds of course)

I know Prusas have lots of issues due to having always to manage 2 motors to drive the Z axis. I am wondering about the 2 motors per X and Y axes in #Quadrap-3d-printer aren’t they getting out of sync to make the moving rod a tad skewed and to influence the dimensional accuracy of the print? Also I see you use string exclusively, when that walks on the motor coupler/winch, isn’t the minute change in length translating to the part in a change of the printed dimensions? I am just wondering cause I’ve been an ardent supporter of spectra drives but different people around the net have made measurements and almost always the “walking” was influencing the end result. Of course the shorter the distance the moving rod travels the less walking => better part. Sorry for too much talking :).

I can only see it via the notifications in the top right of the screen :slight_smile: … nothing in the feed. But was in the feed initially.

Great Job!!!

@Florian_Ford i had the same thoughts initially motors do not seem to get out of sync (compared to other printers they stay at room temperature due to very low resistance/weight applied to them). even toothed belts have tolerances and i doubt that the cheap pulleys used do any better. anyhow, all the others here should have more experience than me. pro dyneema is less noise and price. my cheapqr outperforms my i3 mk2 original. all black/grey parts were printed on it. but i do not want to talk you into something :slight_smile:

@mb_x1 I am following #Quadrap-3d-printer for some time now and after I would have messed around with my own design for a while, to learn the hard way the whole thing I will settle perhaps on another design. With Quadrap I can’t wrap my head around accepting so many motors for XY :smiley: … I know I know …

@Florian_Ford i totally understand :slight_smile: i like the qr frame construction most. damn robust. no expensive corner brackets/cubes. if you are uncertain but have some profiles lying in the attic just build one of the xy gantries and test for yourself. this is what i did with the motedis profiles… i think the prusa’s fail not because of the dual z motors but because of several other reasons (if they fail at all of course): unstable z “sheet”, fix mounted heat bed, massive x wagon, inductive sensor for bed levelling (can’t do it manually any more…), on the wobbly z sheet sits usually a spool holder, … nevertheless you can get fine prints out of it.

@shauki I salute your design it is one of the more interesting designs out there and especially since I’ve come up with a frame built the same way as yours and came to learn about your Quadrap when googling to find a suitable name for my #SCOUTcorexy design, which is named after the scout towers that use the same beam construction… anyway after I finally build my own Scoutcorexy I intend to look closer at your quadrap.

cause others didn’t and a few names is not statistically representative :slight_smile: … so it’s not logical to depart. And also because my design is corexy and I have to start from somewhere.

I also value sharing experiences and highly regard those examples you linked me to. But I also see several successful corexy builds, while secretly becoming fond of the ultimaker cross-rods gantry. I also believe delta printers are the sweetspot for consumer grade 3d printers.

@shauki ​ I will openly admit my issues on my Corexy were my own fault in component selection. I chose PBC Frelon linear bushings on ceramic coated aluminum rods. They work great but hate any misalignment. I also shouldn’t have stacked two bushings so close together on printed parts (the tolerances of printed parts make this a bad design choice).

If I did corexy ever again I would make different component selections. I don’t think there’s anything inherently wrong with Corexy. But also feel it’s not the end-all-be-all of motion platforms. Just one of many good possibilities. I think a key factor in a high quality corexy build is a good method for balancing the tension between those two long belt paths. I did not have this, and so caused me many problems.

@shauki @Eclsnowman @Florian_Ford it is much more easy do get the corexy gantry wrong than getting a qr setting “wrong”. especially if you design from scratch. i don’t like that you have 2 different masses to accel on corexy. y the full carriage and x only the slider. what made me finally decide for @Michael_Memeteau 's printer as base were the onshape CAD files.

that’s actually a good point I haven’t considered before. Thanks for sharing.
The two masses being different were a real hindrance? How did the different masses affect you in printing? Where did you notice them as a problem? I am asking this because in corexy both masses are pulled by each motor for all moves.
@Eclsnowman Did you have the need to adjust the tension of each belt indivifually? Did you try to solve that problem?

@mb_x1 Sorry for hijacking your post for what came to be more about corexy :-s

@Florian_Ford my main “problem” was having the belt tension right. if it is not equalizing your gantry is basically not perpendicular and thus your (linear) bearings are braking => you get ugly vibrations at certain movements. regarding accel: try it for yourself and see how well it is going, just push it. of course there are corexy designs using wheels instead of bearings. i’m done with it, part to my lack of skills and because i found a better solution for /ME.

i’m sure if you could see a QR in rl action you would trash your own design same way as i did.

anyhow more questions to corexy design and optimizing it should go somewhere else.

understand. thanks.