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Jan 13, 2018, 09:14 PM
Lee Liddle
Knife Liddle's Avatar
Quote:
Originally Posted by Par_18
Good idea...I'll keep an eye on it. Past failures have only occurred at either the front or rear portion of the blade base where it is notched to fit in the rotor hub and rotor cap. As long as the blade is not allowed to move there, I think it will be OK. I think it will be sufficient but testing will find out for sure.
I agree with that......don't ask me why!
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Jan 14, 2018, 01:53 PM
Registered User
demetrius's Avatar
Quote:
Originally Posted by Par_18
Hey guys,

I'm back after a bit of a break. I've been working slowly over the past few months to improve the high power design to ensure it will run safely for many, many flights. The main issue was the use of adhesive as the only method of ensuring structural safety at high RPM's. This simply is not enough to operate any fan that uses plastic blades. At this point, I am very familiar with the failure point and as a result, I was able to work out a process of using 3 screws that screw into the rotor hub to retain each blade. I will post all the details here in the near future but just wanted to let you all know that I have not forgotten about this project.

Additionally, I am just about complete with testing of the 18s/22lb fan and will be selling it next week with an ESC and motor RTF. Below are two test videos on 16s and 18s for all the details. This is an excellent fan for A/C in the 20lb range with a max thrust of 24lbs and settled thrust of 22lbs. If anyone is interested, please shoot me a message or just look for the ad in the classified section next week.

I also plan to make the 18s setup available as a kit with motor/ESC/new rotor blades/intake lip/tailcone/all hardware over the next few months. The projected cost is $800 shipped.

The other two variants that will be available will be a 25lb fan and the 30lb fan. Both will come fully assembled and tested with ESC as well. Details to follow!

18s/22lbs settled:
https://youtu.be/cpK22v5dFlU

16s/18.5lbs settled:
https://youtu.be/59ymsoooPqM
Excellent work Par!!!
Latest blog entry: "Is that a Turbine?" Not...
Jan 17, 2018, 06:00 PM
BFMA #13, aka Rogue 13
mongo's Avatar
anybody got any burned up/failed of the Flyer model, fightercat esc.
i need to scavenge a few heat sinks to use on some converted marine esc.
Jan 17, 2018, 06:52 PM
Lee Liddle
Knife Liddle's Avatar
I think I do. Will check
Jan 22, 2018, 11:19 PM
Registered User
Thread OP

Finally got some parts


After a whole month of waiting, I received some of my 3D printed items that I needed to finish assembling the high power setup as well as a new tailcone for the 56mm/18s system. Below are some pictures of all the goodies.

The tailcone on the 56mm TP motor (pictured) helped keep the motor 50 deg F cooler after a full power run for 4000mah worth of capacity. This is my standard test profile to preserve my batteries as much as possible. I have been running the snot of this fan over the last few weeks. As a result, I've been moving the thermocouple around inside the motor can to find the hottest part of the motor. I think I have located that part, which was reaching 250 def F after a test run as described above. With the tailcone in place, the motor only hits 200 Deg F by the end of the test. Oddly enough, it also makes the "whoosh" nice sound even better.

Anyways, just wanted to share some of the progress. The 30lb fan testing resumes tomorrow and I hope to bring back nothing but good news on that front. This fan is also pictured below in the test stand with a gold anodized spinner.
Jan 23, 2018, 12:26 AM
BFMA #13, aka Rogue 13
mongo's Avatar
looking good, sir.
Jan 23, 2018, 01:59 AM
Lee Liddle
Knife Liddle's Avatar
Looks awesome as usual Par. That's great news about the heat reduction with the new tailcone. I'll be ordering one of those for sure.

Best of luck with the Cat-8. I have high hopes that your tests will be successful.
Jan 23, 2018, 02:15 AM
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Trevor
tag's Avatar
That's some very nice work.
Jan 23, 2018, 11:54 AM
Pro Hoarder
turbonut's Avatar
Well they sure do look cool...And some pretty killer numbers coming from it. Nice work
Latest blog entry: In flight
Jan 23, 2018, 02:56 PM
Registered User
Thread OP
Thanks guys. The wait and effort was def worth it for this setup. It took some time to refine all the individual parts and none of this would have been possible without the low cost option of 3d printing for the prototyping.

Anyhow, I’m doing some 20s and 22s runs today to see how the fan does. I have no doubt it will hold up but the first few runs are always a nail biter. On 20s, this is a 26-27lb fan peak and settling at 24-25lbs. Screenshot attached below a few seconds after peak. I am only seeing 142amps settled at this voltage. This means we can run the same setup with a higher kv motor on 18s and still produce the same numbers but at the cost of another 15-30amps. I think quality 8000mah batteries should be able to handle this with ease. The fan ran very smooth and the motor barely broke a sweat in terms on temperature after a good 4 mins.

Next test will be on 22s and I expect to see 29lbs peak, settling around 27. My batteries are relatively weak and I am having to use 16000mah capacity to get numbers repetesenting some good 8-10ah batteries.
Last edited by Par_18; Jan 23, 2018 at 03:56 PM.
Jan 23, 2018, 07:37 PM
Registered User
erh7771's Avatar
Nice, 25 lbs of good steady get gone is nice, the efflux must be crazy

What do you think your build price for the fan is for those of us who don't want to put these together ourselves?

Thx in advance
Jan 23, 2018, 09:15 PM
Registered User
Thread OP
Quote:
Originally Posted by erh7771
Nice, 25 lbs of good steady get gone is nice, the efflux must be crazy

What do you think your build price for the fan is for those of us who don't want to put these together ourselves?

Thx in advance
Efflux is the next thing to measure. It is just difficult to do because the equipment available to measure it isn't necessarily the greatest. The best to get a read on the airspeed is to measure it quite a ways downwind, which requires some kind of exhaust ducting. However, once the duct is in place, other variable will suffer. Either way, i'm going to spend some time on trying to find a good way to determine this information.

For your second question, any setup pushing above 10kw (24ish lbs) will only be available as RTF. The assembly requires certain components needed to drill the rotor in the right spot at the right angle for all the retaining screws to line up properly. I don't want anyone taking shortcuts during the build on these because that could become very dangerous, very fast.

I don't have an exact answer for you for on the price. All my time has been going towards the development and as soon as I find a few moments to look through all the expenses, I will be able to give you the cost. If I had to guess for now, it will be somewhere between $800-$1000 for the 25-27lb fan, which will include the ESC/tailcone/intake lip as well. Build time will be around 2-3 weeks. The 30lb fan will be between 1100-1200, also with ESC/Tailcone/intake lip for that price.
Jan 23, 2018, 11:30 PM
Registered User
Thread OP
Well guys, I think we have a winner. Its late so I won't say much but the video is linked below with two screen shots. First screenshot shows peak numbers and the second shows settled numbers at 3.5v/cell.

Couple things to note. This fan showed slightly better performance than the first test I did a few months back. I believe this is due to the better intake that I am using now. The previous intake lip caused made some noises that can only be described as "cavitation" at these high power settings. I imagine the volume of air going though the fan to produce these numbers is immense. I don't think that fan was getting all the air it needed and the numbers that were produced reflected accordingly.

This test, however, showed very linear performance up to the 30lbs. The fan managed to do this at a peak RPM of just a little over 38k, which is bested by almost 1k as compared to the old test run. On top of that, the fan ran smooth and the motor handled the power well. This test run was not my usual full power for 50% of battery capacity because my batteries can't handle that. So, I did this more like a what would be expected from an average flight. Once again, with some quality batteries, 30lbs is achievable on 20s/8000mah packs. The current will be in the neighborhood of 190amps in this case but I think we are not too far from that level of battery performance.

Enjoy the video for now but I'll be doing a lot more runs on this to ensure it will hold together. I fully believe it will because the rotor has been strengthened significantly and should easily be able to handle the forces produced at 38k. This will be my test limit but i'm sure Lee will push it a little further.

Video:
"Cat 8" Dynamax EDF 30lbs (4 min 51 sec)
Jan 23, 2018, 11:43 PM
BFMA #13, aka Rogue 13
mongo's Avatar
looking real good there.
i may not have to wait on the JF 130 to go ahead with the Jet Legend F-20 project.
Jan 24, 2018, 06:17 AM
Lee Liddle
Knife Liddle's Avatar
Wow, what a beast! Those poor lipos were doing their best to keep up. Fresh lipos should easily sustain 30lb in long bursts through most of a flight. Looks and sounds awesome.


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