Hello guys,

I’m totally puzzled. I know acetal rods are a lightweight replacement for steel rods etc and I was wondering if I could use them for the X axis of my 3d printer project. I see a lot of infos about 3d printing with acetal filament, butr, apparently, nobody ever tried to switch their rods to these to gain weight?

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Having morn looked into this issue at all I would say the problem is bending. Or perhaps wear as the acetal will erode faster. Really, if you have the money you should give it a go! See what happens. All pioneers do and sometimes they make amazing breakthroughs.

I dont think it will work, the acetal is not stiff enough. Also, steel shafts are precision ground, while acetal does not have a precision finish. I have some acetal here in my workshop and the bars are not even straight. But for turning small low friction parts on the lathe it is brilliant.

Hi @Maarten_4,@AcrimoniousM, thanks for the input,

Right now, for my project,(picture attached) I have 4 600 mm long 16mm rods (hardened steel), but, according to bending formulas, I already have to expect, for, let say, 300 grams on the carriage, bending down for something between 0.2 to 0.4mm in the middle. Fortunatly, My Y axis is made of linear rods rails, clamped on a 4545 extrusion, so no bending there. But for the X axis, it does matter. Not only it is heavy, around 3kg to move around, so, probably bye bye for more than 40mm/s, but I do hope that the autoleveling will compensate properly (theorically… yes it should) and that my Z axis resolution will be good enough for it to be totally transparent :slight_smile:

I also had delivered carbon fiber rods 16mm / 600mm, I keep them there, but they definitly are not as smooth as steel. nevertheless, I’ll try them, but I wonder if I should “help them get smoother” using classic bearings, of if I should immediatly go for IGUS RJ4JP-01-16 palier linéaire drylin palier lisse imprimante 3D RepRap Makerbot LM16UU | eBay or IGUS RJMP-01-16 palier linéaire palier lisse imprimante 3D LM16UU LME16UUU | eBay plastic bearings… Anyway, I’ll order one of them brands for sure because i believe it will do better results on steel.

On a side note, I suspect that I should get rid of the rods for the X axis and probably go for a 600mm long 2060 extrusion like this one http://cdn1.bigcommerce.com/server2300/itwgldve/product\_images/attribute\_rule\_images/243170\_zoom\_1475273449.jpg here Linear Rail - V-Slot® Linear Rail - OpenBuilds Part Store, if I can source it.

Feel free to give your opinion :-))

Hi, thanks exactly are you doing to make your extruder so heavy??? And that you need such thick rails?

I’ve designed my own CoreXY in a similar setup that just uses standard 8mm diameter silver steel rods with no issues.

Hy @AcrimoniousM, well, good questions!

1) Direct drive adds weight of the stepper.

2) Optional Diamond head with(or without) direct drive is possible (although already kindo obsolete vs palette or even Y solution)

3)… Well. do you also have 600x600mm? Because if you do, and if you have 8mm rods, then I may have been banging my head to the wall too much. Do you have pics?

4) CoreXy is great to move all steppers out of the mouvements, goog call. Not for me though. I thing at a time; I just finished (barely) my 600mm delta :-)))

PS: for the Y axis and bed, I had the rods already, so I reused them. For the X axis, I based the section on the bending formula for up to 300grams without perceptible bending. Better safe than sorry, I thought. May have been wrong there :-/

Hey!

1) yeah, but not too much, I’ve got a pretty large 59Ncm NEMA17. Thing is, for 1.75mm filament you only need about 13Ncm so there’s definitely no need for a Gregs Wades extruder.

2) unfamiliar with that hot end, I’ve always stuck with E3D-V6.

3) my printer is 500*500, print space about 400*400 but yeah, you’ll want to increase your bar duameter, but not by much. 10mm would be good, 12 better. 16 seems a bit too much!

4) this was my first ever printer build, you can check out my progress here: www.youtube.com/user/acrimoniousmirth

Honestly, if you’re that worried about it then the 2020 Vslot extrusion will be perfectly fine. Check out the D-bot design on Thingiverse too, it’s a good one. If you’re in the Uk you may find it easier to buy from Ooznest instead.

Oh yes, there was also a printer design that used acetal rod runners instead of V-slot wheels on the V-slot. ,I had cheaper and no regrets. Worth a thought too.

@AcrimoniousM Mmmm. I think I’ll follow your advice. I hate these heavy rods anyway, so I’ll do 10mm and rely on light extruder on top of autoleveling, and… well… Keep you posted! I’ll check your link later when back home :slight_smile:

One, it’s not stiff enough, two, it’d be terrible for the bearings to run on, carbon fibre would be even worse, especially at elevated temperatures! You’d be talking lifespan of hours if you’re lucky.