# Specific 3D Printers, Scanners, & Hardware > RepRap Format Printer Forum >  Any tips for pringing very small parts?

## Sabbath

Hi All, if i'm not concerned about print time or filament use, how would i optimize for print quality? Is slower always better? Is lower layer height always better? At what point when lowering speed and height to you do the returns become negligible?

Temperature recommendation for ABS? (using 245 deg Celcius at the moment).

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## curious aardvark

well low layer heights arn't necessarily a good thing. I pretty much only go down to 0.2 mm anyway. 
Slower printing though is necessary for small parts as is active cooling. It also helps to print more than one piece at a time, to give more cooling time between parts. 

Smallest things I've made to date are 5mm 8 toothed gears and 3mm rubber tires. 
The gears were made from colorfabbs xt(petg) and the tires from flexismart flexible rubber. 

I didn't need a brim for them - but it an be useful if there is on;y a small area in contace with the print bed.

I don't use abs :-)

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## iDig3Dprinting

use a smaller nozzle diameter. adhesion to the print bed can be an issue so as @CuriousAardvark says, you may want to explore the use of a brim. We had to do this recently when printing out a molex seal, just couldn't get it to stick otherwise. We used ColorFabb nGen Flex for this. ( https://www.idig3dprinting.co.uk/new...abb-ngen-flex/ ).

The problems come if you need good definition. Printing lots of detail on a small model is obviously harder than just printing a small cube.

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## Todd-67

.2mm nozzle and slow your speed way down. if the part has fine details in the z direction a reduced layer height would be a benefit.

 Your 245 degrees might be ok but it really depends on the filament itself. I am usually down around 230-235 but I print out a temperature test print every time I get a new roll to test what is best.

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## curious aardvark

be aware for slower print speeds you generally need to drop the temp a little. 

How small are you talking ?

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## Sabbath

Here's the bit;
https://dl.dropboxusercontent.com/u/...clip-size5.stl

Also I had read that ABS flexes before it breaks but this part seems quite brittle.

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## Sabbath

> Your 245 degrees might be ok but it really depends on the filament itself. I am usually down around 230-235 but I print out a temperature test print every time I get a new roll to test what is best.


Can you explain this process a little further? What indicates the temperature is too high or low?

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## Todd-67

http://forums.designfutures.club/t/t...la-hips-etc/84
That is one example I don't make my tower that tall but under good light you can see the changes. Different colors can prefer different temps even from the same manufacturer.

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## curious aardvark

yeah I always had problems with abs breaking. I also found that pla was a lot more forgiving. 

For something like that I'd probably use either pet-g or esun flexible pla. Both have much better layer adhesion than abs or pla, and that's going to be your weakpoint in that model. 
Personally I'd put reinforcement on the inside of the gap between the two parts of the sticky-in-bit (must be a proper name for it lol) 

Size wise, it's not that small - currently printing a much smaller batter cover :-)

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## Sabbath

Thanks curious. The idea was that the two bits would flex as they are pushed through the hole, so there's no reinforcement because those parts are supposed to flex. But I guess there will be stress concentration at the base, so i'll think about how to spread that out a bit. The clip is for a door trim in a car, so i thought PLA would not handle the temperature of the car sitting in the sun. If you think PLA could handle that i'll give it a try tho.

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## curious aardvark

lol cars stittig in the sun not usually an issue in the uk. But bear in mind that the glass popint is only the pint the plastic starts to bend, it won't actually melt untill it hits the 180c mark. Given that this is aclip that isn't under any real tension - it would need to get hot enough in the car to melt all the plastic components before you had any problems. 

The issue is vertical layer adhesion. pla is better at that than abs (mainly because it doesn;'t shrink anywhere as much), but if you want a properly bonded part use pet-g. It's layer bonding is much better than abs or pla. 
Also one reason I'd use esun flexible pla. It's a really stiff flexible - would be ideal for this kind of clip, and layer bonding on all the flexible filaments is as good as injection moulded parts. 

Though it does depend what printer you have. If you have one with a heated enclosed print volume - then you will get better layer adhesion from abs. If you have an open enclosure - then my advice would be don't use abs, period. 

I'd still add some reinforcement at the base, which is the weak point, it will still flex, just less chance of breaking.  And if using a flexible filament I'd be inclined to leave the column solid for added stiffness.

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## Sabbath

Ok thanks aard. I will follow your great advice!

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