Extruder Gear Set

Hey guys,

I recently got a Makerfarm prusa i3 8inch (3 weeks ago)

Now i am thinking to make a replacement set for my Gear set, just to be sure if it breaks,

But i do not have any ABS at the moment and normaly most people do make them from out of ABS (I bought PLA since this is in my bedroom and heard its not realy that healthy)

I probably will buy 500 grams on my next order and see how it goes, But anyhow.


I wanted to ask if PLA is OK for making a gearset with?
Since there must be a reason why most people would like ABS more for this.


Thanks for the help ^^

I think PLA is actually preferred choice of material for gear parts for some people. Well, I did say some people - I don't want to start a war on this. LOL

I actually have a Makerfarm Prusa i3 8" bed myself, and I re-printed the extruder gears, too.

Actually... I did a little bit more.. I downloaded a modified design of the extruder body/motor mount, which holds the motor above the X rails, instead of holding it in a position where it sticks far out to front, and printed it. I am using that one now and I can tell it certainly reduced the amount of vibration. I also replaced the X carriage, X motor, and X idler - they are smaller than the original wood version, and they feel a lot more sturdy and firm, so I like them a lot, too.

Anyway, I am also using the gears I have printed, too, and I used PLA for the big gear and ABS for the small gear. I have mentioned this in my other posting here, but my thinking was that it would be easier for me to re-print and replace the smaller gear, so I would use ABS so that it will take all the wearing and grinding against the harder PLA big gear.

I actually asked Colin why he used ABS in email, and he replied he used it becaus it's easier material to work with (btw, he's always very prompt answering questions). I had to ask him twice to make sure I understood him correctly - to me PLA is easier material to work with. Since ABS and PLA have their own pros and cons, I guess it's just a matter of opinion and personal preference when someone says one is "better" or "easier to work with".

Besides the small gear, I used ABS for the extruder body and X motor - basically I was following other poeple's common advice that PLA will start deforming once it reaches to 50 C, so we should use ABS for anything that touches the motor.

Another reason that people may want to use ABS for gear is because it's "supposed to be" better with smaller prints/printing small area. Since you would want high precision with gears, you may want to use ABS. But then again, the gears and other parts I've printed with PLA just as accurate...

So, long stroy short, just for gears, I won't worry about using PLA. I haven't been doing this too long, but during my short 3D print hobbyist career, the only time I use PLA is when I need to print something that needs high temperature tolerance, or when I only have ABS filament.

Any links for those parts you have done?

Well imo the kit is very sturdy and such, only makes a hell of a noise,
Probably alot of that is from like you said from the carriage that holds the motor and hotend

Here's a picture my new extruder - purple/hot pink parts are PLA and gray/silver parts are ABS.



Edited 1 time(s). Last edit at 09/13/2013 01:28PM by Yamster.

could i also do except the small gear also PLA like the other parts?

Well its due just i realy dont have anything except PLA at the moment

For the gears, I used the original (to MakerFarm Prusa i3, that is) design. You can download the STL file from MakerFarm web site - there is URL for the printed parts in the build instructions.

And for the extruder body/motor mount, I used this variation: [www.thingiverse.com] I only used the extruder body from this design. I like the design of the gears which came with my MakerFarmkit (round edges). Also, I like the MakerFarm's filament idler more, too.

Please note that, however, this extruder has a deeper opening for the hot end at the bottom. When I installed the hot end (btw, I have J Head, not Magma) the same way I did with the original extruder (using that wood mount plate), I could spin the hot end with my hand. It didn't move too easily, but it wasn't held by anything firmly. I think that's because it's not pressed tightly against the bottom of the extruder, now that this new extruder has a deeper hole.

So I got rid of the mounting plate, and inserted the J Head all the way, then stuck a couple of mini screws through the small holes. The hole location is exactly at that narrow part of the hot end near the top (where mounting plate used catch the hot end), so after inserting a couple screws, it's quite a tight fit. Not sure if this is actually how the hot end is supposed to be mounted, but works for me

One other complain I have with this new extruder is that the two bolt holes at the top (for long M3 screws which will push the filament tightly against the hobbed bold) are a little too big - the M3 nuts spins around in it. I had to stick in some pieces of paper in it to stop it from spinning...

Edited 1 time(s). Last edit at 09/13/2013 01:49PM by Yamster.

luigi Wrote:
-------------------------------------------------------
> could i also do except the small gear also PLA
> like the other parts?
>
> Well its due just i realy dont have anything
> except PLA at the moment


Also is it necessary to paint the kit?

Kinda going off topic but ye ^^ had that question for a while now

luigi Wrote:
>
> Also is it necessary to paint the kit?
>

I don't think it's necessary. I did it for a good look. LOL

> Kinda going off topic but ye ^^ had that question
> for a while now

Well, I asked Colin about it, too (yes, I bugged him quite a bit a lot of questions - I must be on his black list by now).

However, my question was somewhat the opposite of yours; instead of wondering if I NEED to paint the kit, I assumed the default is not painting it and wondered if it's OKAY to paint.

He did not disapprove or advise against the idea of painting the wood parts, but he didn't give me his blessing, either. He just said, he's never done it himself, but he knows a lot of his customers have painted it.

Hah,
He must be quiet busy then since i guess everyone asks him alot including myself,
He is a great supporter and i wonder how he can answer so much xD

Anyhow do you think its possible if i would place PLA parts as base aswell after the one gear?
Since normaly those dont heat up at all.


Yamster Wrote:
-------------------------------------------------------
> luigi Wrote:
> >
> > Also is it necessary to paint the kit?
> >
>
> I don't think it's necessary. I did it for a good
> look. LOL
>
> > Kinda going off topic but ye ^^ had that
> question
> > for a while now
>
> Well, I asked Colin about it, too (yes, I bugged
> him quite a bit a lot of questions - I must be on
> his black list by now).
>
> However, my question was somewhat the opposite of
> yours; instead of wondering if I NEED to paint the
> kit, I assumed the default is not painting it and
> wondered if it's OKAY to paint.
>
> He did not disapprove or advise against the idea
> of painting the wood parts, but he didn't give me
> his blessing, either. He just said, he's never
> done it himself, but he knows a lot of his
> customers have painted it.

The smaller gear? I think you can use PLA for usre.

Like I said, the only reason I used ABS for the smaller gear was to make it softer than the bigger gear intetionally, so that it will be the one that wears out instead of the other gear (or both).

No i meant the base for example, and the other plastic part that has the bearing,

Can those be PLA aswell?

Everything can be PLA. In fact, I recommend that both gears be PLA, as long as you have a high-torque motor that doesn't get too hot in normal operation. The extruder its self can be PLA as long as you have a fan blowing under it to keep it cool (not recommended for printing ABS as it causes print warping, unless you use some sort of duct to keep airflow away from the print).

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Quote

Like I said, the only reason I used ABS for the smaller gear was to make it softer than the bigger gear intentionally, so that it will be the one that wears out instead of the other gear (or both).

The small gear will always wear faster because its teeth are used more often.

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[www.hydraraptor.blogspot.com]

Thanks for the help ^^
Well i was going to buy some ABS over a few days/weeks depends when my fillement gone,

My steppermotor easly gets 50-80c. so i guess that better stays ABS. (small gear)

for the rest i've got everything now in PLA ^^

We will see i guess, When i got my ABS and if it prints well, due i always hear such bad story's haha

Anyhow thanks for the help guys!

Actually, I don't think the heat from the motor will be transferred to the small gear that efficiently via the shaft. The only thing you would have to worry about deformation from the heat from the motor will be the things to which you mount the motor, like extruder main body or X motor, etc.