accuracy aka resolution?

I'm sorry if this has been answered somewhere, couldn't find anything.

Printers like Solidoodle and makerbot print at around 0.1 mm accuracy. While the official Solidoodle site says it is hard for an untrained eye to tell if the model was 3d printed or not, *all* the images I've seen from all the printers have very noticeable lines caused by the 3d printing process:
http://www.flickr.com/photos/easthaw...pool-makerbot/

Some people say you can improve it by 'finishing' with things like acetone, but from what I've seen that melts the plastic,which while smoothens it, also makes it change its shape. While that's not so bad for organic models, things like custom phone/tablet cases, replacement plastic parts will become asymmetric and weird with finishing and look like done with cheap plastic and not smooth at all without finishing, in my opinion.

So I'm wondering how accurate Peachy is.

Accuracy and resolution aren't the same thing.

Resolution is how big the basic unit is. Accuracy is how close it is to where you want it.

You can have very high accuracy while having low resolution.

I don't think they've got any kind of figures for accuracy or resolution, mostly as it's still a work in progress.

For examples of what the prints are like, you might look at the videos for updates 13 and 15.

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Originally Posted by Compro01

Accuracy is how close it is to where you want it.

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I don't think i understand

https://ci5.googleusercontent.com/pr...png?1384906359

The peachy has had some really impressive looking prints so far, like the crystal clear column above. Look into objects printed with the Form1 printer for an example of the quality that is achievable with lithographic printing. You likely won't find the lines you are referring to.

Truth is, we won't know what the final kit can do until it gets to us.

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Originally Posted by cipher0

I don't think i understand

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From an engineering point of view:

Resolution - is pretty much how small the smallest feature can be. 0.1mm is pretty normal for FDM printers like the Makerbot, since nozzles to print smaller parts tend to be expensive, fragile, and very slow. Resolution for each axis may be different; often Z resolution can be easily adjusted.

Precision - is how reliably the printer can do the same thing that it did before. If you print a 10x10x10mm cube and then another 10x10x10mm cube, are they both the same size? Note that precision is not concerned with how close the printer comes to what you wanted. If the first cube was 12.000002x15.000001x5.999999mm and the second cube was 12.000000x14.999998x6.000001mm then the precision of the printer is very high - even though neither is anywhere near to the 10x10x10mm cube that you wanted.

Accuracy - is how close the printer comes to what you wanted, on average over multiple jobs. The example above is a printer that is very precise but not very accurate. On the other hand, you might have a printer where the first cube is 12x9x12mm and the second is 8x11x8mm. This printer has very high accuracy (if you average the two cubes, you get 10x10x10mm) but very poor precision.


Now, with the Peachy:
- Resolution when close to the job is excellent. Resolution when further away will be worse, as a small movement of the mirrors translates into a larger movement of the beam on the resin. On the other hand, when it's very close to the job then focus changes at different points could cause problems. Realistically, it looks like the Peachy's resolution will be more than good enough for very nice-looking parts the size of phone cases.

- Precision is good in the most recent prototypes. They had issues in early prototypes where the mirrors were sticking a bit, so movements were not repeatable. That appears to be solved now by using a different material to support the mirrors.

- Accuracy is going to be down to calibration. If you hang the Peachy above a bath a container, fill it with resin, and hit print, then the result is not going to be accurate. There'll be a fair bit of calibration so that the Peachy knows its own position and orientation with respect to the print bath. Once that's done it should be very accurate.

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Originally Posted by Slatye

Realistically, it looks like the Peachy's resolution will be more than good enough for very nice-looking parts the size of phone cases.

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Thanks for the info and thats great to know.
What do you think about things like tablet cases? (can be up to 20x20cm)

you would need a large area but shallow tub and the peachy mounted a fair(and correct) distance above the tub so that the peachy can scan all the wanted area inside the tub