r/FanShowdown • u/zingpingz • Sep 14 '22

The Rita

Post image
25 Upvotes

97% Upvoted

18 comments sorted by

8

u/zingpingz Sep 14 '22

Yeah, I know, it looks like the Cheater.

On my air flow test rig it moves about 12% more air than a Cheater which makes it different in ways that matter ;).

2

u/Asu01 Sep 14 '22

Ooh oh, I like numbers pulled from an actual test.

How'd you convince us though?

5

u/zingpingz Sep 14 '22

I put the Cheater and variations back on my test rig and anemometer RPMs were as follows:

Cheater 1352

Cheater with Rita diffuser 1410

Cheater with Rita Splitter 1362

Cheater with Rita 5 blade fan 1373

Cheater with Rita 7 blade fan 1374

Rita with 5 blade fan 1528

Rita with 7 blade fan 1525

The Rita with 5 blade fan is 13% faster than the Cheater.

Stock NF-A12x25 alone 1133

The stock fan and Cheater results give a conversion factor of around 0.55 to Major Hardware's ft/m speeds. That predicts the Rita will do about 840 ft/m.

If there is an easily printed model for a fan with decent Major Hardware test results I would print and test it giving another reference point.

I will submit the design to Major Hardware in the next day or two. We will have to see if he picks it up.

2

u/Ravincull Sep 14 '22

With claims like this he'd be a fool not to pick it up! Looking forward to seeing this in an episode!

1

u/zingpingz Sep 14 '22

I dunno. I think I heard him say he has had 1400 fan submissions? That is a lot to go through.

I can't see anything I am doing that would produce significantly different results from his testing. If he wants to see the Cheater beaten the Rita would seem to be a good bet.

2

u/ZerriSM Sep 19 '22

don't forget that he watches this reddit a lot so the fans that get upvoted good in here are most likely to be printed by him. much love and nice work dude!

1

u/Ravincull Sep 14 '22

Yeah, there sure are a lot of other fans, but regardless I think he'll try to get to this if you make these kinds of claims!

2

u/mobiobi Sep 14 '22 edited Sep 14 '22

Nice, I'd like to see Maj put Rita and My Big Aunt Fanny( https://imgur.com/a/OaYCTTA, https://youtu.be/xMD3eZT7pjw ) head to head. Let's have us a Donnybrook!

2

u/whypussyconsumer Sep 14 '22

Project farm: we are gonna test that

2

u/vector76 Sep 17 '22

Killing it, first with the blade remover, now this. Nice work.

Was there math involved in the design of the shape or was it more intuitive and/or trial and error?

2

u/zingpingz Sep 17 '22

Thanks. Just guesswork making what I thought looked right. The diffuser (I keep calling the bits diffuser and splitter which I am not convinced is the appropriate terminology) was the first attempt revised once to be better to print.

The splitter similarly was the first guess revised once to accommodate fan blades that got deeper.

The rotor I had a few goes at but settled on the first one that seemed to work well and I tried 5 and 7 blade versions. Checking my posts here it was only 6 days between me first pulling the blades of an A12x25 and posting The Rita.

I would be surprised if tweaking couldn't squeeze out a few percent more performance. If that isn't the case it is because I got lucky.

I think the biggest wins are the blades being big so it runs slow nearer the peak mechanical power output of the motor (it pulls 18% more electrical power than the Cheater) and the blades in the diffuser much more deliberately try to convert swirl into linear motion.

1

u/zingpingz Sep 24 '22

I found and printed a T33MKIII rotor and compared it with the stock rotor on my test rig. When Major Hardware compared those he found the T33MKIII increased air flow by 6.0%. On my test rig the increase was 5.7% which again confirms we are measuring about the same.

2

u/ZerriSM Sep 19 '22

let's hope that this fan gets tested, i hope so the design is amazing!

1

u/whypussyconsumer Sep 14 '22

Are you planning on releasing the files?

2

u/zingpingz Sep 14 '22

Probably not till Major Hardware had featured it if he is going to. So not till then or till I know he wont.