Sonic Mini 8k

[timwatson]

It actually is true.

You get more antialiasing when the voxel size isn’t a good round number in all X,Y,Z axis. All axis need to be in agreement.

The z axis size is a part of the voxel dimension that’s the limiting factor here.  In essence we are limited to whole numbers with .01mm. So .022 can’t be maintained on the SM8k the same way the SM4k can’t maintain a .035mm height because the motor will be doing what called microstepping. Ideally the z-axis height would match the optical resolution but in this case we can’t do that. Z axis microstepping doesn’t reliably happen (read can’t reliably happen) some mechanical rounding will occur either up or down and your print will actually look worse when microstepping happens.

I’ve been 3d printing awhile (2014) and have designed 2 of my own delta kinematic based machines. .01mm for these cheaper nema 17 1.8 degree stepper motors is mostly an immutable fact. You can use a 9 degree stepper but you will lose torque. And these things with the peel forces need the torque. If you did use a 9 degree stepper you could work in .005 increments so the SM4k would benefit but not the SM8k.

I hope that helps. Doing a search on microstepping and 3d printing will yield a wealth of knowledge.

[Chris333]

I just assumed 0.05mm layers. Carry on.

[timwatson]

I just assumed 0.05mm layers. Carry on.

I’ll do that test next.

[Chris333]

Naa no need. I just have printed everything at .05 layers. I guess the thinner the layer the less time you need, but as a whole the print takes longer.

[timwatson]

Naa no need. I just have printed everything at .05 layers. I guess the thinner the layer the less time you need, but as a whole the print takes longer.

It’s prob the best way to test two optically different machines. Same playing field basically. You should try .03 sometime. On the SM4k it’s a great sweet spot. I can help you print more quickly. If you want to try my config file.

[Chris333]

On things like a large window opening .05 is better. If not the opening tends to sag a little.

[Lemosteam]

0.5 wire supports on angles from the side will easily trim away, especially prior to cure.. Just make sure you have less than 3mm unsupported.

[JeffB]

It actually is true.

You get more antialiasing when the voxel size isn’t a good round number in all X,Y,Z axis. All axis need to be in agreement.

The z axis size is a part of the voxel dimension that’s the limiting factor here.  In essence we are limited to whole numbers with .01mm. So .022 can’t be maintained on the SM8k the same way the SM4k can’t maintain a .035mm height because the motor will be doing what called microstepping. Ideally the z-axis height would match the optical resolution but in this case we can’t do that. Z axis microstepping doesn’t reliably happen (read can’t reliably happen) some mechanical rounding will occur either up or down and your print will actually look worse when microstepping happens.

I’ve been 3d printing awhile (2014) and have designed 2 of my own delta kinematic based machines. .01mm for these cheaper nema 17 1.8 degree stepper motors is mostly an immutable fact. You can use a 9 degree stepper but you will lose torque. And these things with the peel forces need the torque. If you did use a 9 degree stepper you could work in .005 increments so the SM4k would benefit but not the SM8k.

I hope that helps. Doing a search on microstepping and 3d printing will yield a wealth of knowledge.

Interesting info Tim...  When you say "1.8° stepper motor" you're saying each step is 1.8°, or 200 step increments per revolution, right?

Also...  You later say "9° stepper"...  Don't you mean 0.9°"  That would halve the angle per step (doubling the steps per rev), which would give you 0.005mm or 5 micron layer thickness.

Better precision/more torque could be gained by having the stepper motor in series with (or integral) a gearhead, but I'm not sure you could do something like that on these small inexpensive steppers.  We do it on some of the servo motors for the big laser machines the company I work for builds.

Jeff

[timwatson]

Yup those clarifications are correct @JeffB 200 revolutions for a 1.8 degree stepper - yes. Also you were correct that should have been .9 degree. I used those on my delta machine and they are really nice. I’ve never tried a .9 degree stepper on one of these resin machines it would be an interesting test. You also have to change the steps/mm in firmware which is maybe more hard than it should be on the chitu machines.

[Chris333]

So did you break this thing yet? 

[timwatson]

No, not yet. I am getting ready to add the magnetic build plate. I am trying to tweak the print times to be faster as well. It’s a really great machine but times projected don’t match the actual print times. I am thinking thats a Chitu 1.9.1 issue. I will update when I get more time with it.

[John]

No, not yet. I am getting ready to add the magnetic build plate. I am trying to tweak the print times to be faster as well. It’s a really great machine but times projected don’t match the actual print times. I am thinking thats a Chitu 1.9.1 issue. I will update when I get more time with it.

Chitu has been flakey lately .. I can't get it properly slice my Mono files .. but works fine on MonoSE .. weird

[CNR5529]

Just got notification that my SM8k is finally shipping now, cant wait to see what this thing can do!

Sorry if this was mentioned before but have you tried the 8k resin yet? Im curious how it stacks up compared to other current resins like those by Siraya tech or others.

[JeffB]

OK...

So I'm going to go on a bit of a rant.

I went to buy a Sonic Mini-8K direct from Phrozen a few minutes ago.  I'd been contemplating it for a few weeks and today I got a nice surprise from my employer.  I hit the 25yr mark and found a very unexpected and generous deposit in our checking account! 

Anyway, long story short.  Went to order it, start going through checkout and get to the shipping calculation page.  There's only one option for shipping, Fedex International.  The shocker is that it is nearly $242.00 US!!! 

WTF??!!  One shipping option and it's almost $250??  Are they kidding with this BS?  Is this why Phrozen is selling them for $599 instead of nearly $800 like the few online retailers you can find?

I guess I'll have to wait until an online retailer offers them at a small discount, they're bound to have cheaper shipping.

Unbelievable...

JB

[Chris333]

I went to FB to find the mini 8K group and look around. I guess if you use the Fedex estimator online they quote you about $175 (oct 2021) to ship something that far. (from TAIWAN / Hsinchu)

"TAIWAN / Hsinchu" as the shipping destination, and enter the weight and size of the package as 15kg / 40cmX40cmX50cm to check the actual shipping cost.

Some quotes

The 8k resin costs 50 dollars plus 59 shipping and tax for a total of $121.31 for 1 kg of resin.

Early bird:(oct 2021)
 

Here is the updated version of the estimated shipping fee for the Super Early-Bird bundle:
USA: $149,99 USD

Nov 2021

Thinking about getting the mini 8K in the last few hours of the pre-sale but shipping has gone from $200 USD to over $300 USD since I last checked at the beginning of the week. Sorry Phrozen, really excited about the printer but I’m not paying an additional 65% of the device’s cost just to get it early. Frankly ridiculous.

March 2022

Does Phrozen have a USA store so that we will be able to save some money on shipping costs on the Mini 8K? Two Hundred Fifty Hurt Me Dollars Stings A Lot. Thank you and have a most awesome evening!

https://www.businessinsider.com/russia-war-ukraine-could-triple-ocean-shipping-rates-experts-2022-3?fbclid=IwAR1SiaJc-Op531IP2mvgYR8kC2Lq4SEIFYreD4F9_XgK0ccvfqyoNVvnXik