Thread Tools
Sep 20, 2020, 02:05 PM
Registered User
Aeroplayin's Avatar
I know we discussed this a century ago but I never really gave it too much thought. I was thinking about ceramic bearings as an upgrade and asked Boca Bearing about them. They said that they certainly are an upgrade. Not that I'm questioning the wisdom of individual RCG thread posts, but I do remember some negative things being said. Does anyone have experience with ceramic replacements from Boca? These are ceramic hybrids with stainless races and ceramic balls.
Sign up now
to remove ads between posts
Sep 20, 2020, 02:26 PM
Registered User
p901P901's Avatar
I've used these https://www.vxb.com/Hybrid-Ceramic-B...line-s/135.htm before, but did not notice any improvements. They are not Boca.

In steel bearings at cold temperatures the grease does not lubricate the bearings very well. Ceramic bearings do not use grease so they work better at all temperatures. At very high speeds ceramics do perform better than steel bearings.

Full ceramic bearings can be very pricey. https://www.vxb.com/Full-Ceramic-Bal...e=1&f-12mm=623
Sep 20, 2020, 02:44 PM
Registered User
Aeroplayin's Avatar
Thanks. Flying in FL presents no warm-up issues for lubricants or battery chemistry, but eliminating the maintenance is what I'm interested in and they are high speed applications.
Sep 23, 2020, 01:55 PM
I am not a robot
Sideslip's Avatar
......
Last edited by Sideslip; Oct 01, 2020 at 08:40 PM.
Oct 01, 2020, 07:23 AM
Registered User
Aeroplayin's Avatar
We have been discussing battery temperatures from my consumer report on the Battery Load Test Comparisons thread, and this is something to keep in mind when considering the Temp column. From post #10345 from that thread....

The more I look at my consumer's report, as with any data I deal with, there are measurements that can actually provide relativity that can add more useful comparisons. For example, my linear formula for Usable C should also be confirmed by the area under the load curve, or Ohmic's Lipo Power Band Area (LPB-A). If you do a comparison, there is clear relativity between the two variables, and my number simply puts it in terms of Ah to a recovered 3.7 volts per cell. This is important because it is confirmation of both the used and useful capacity, then the %Cap column uses both to illustrates the difference between the confirmed real capacity versus the fiction capacity from the label.

Along the same lines of relative reasoning, the Temp column as should also be a relative value over time and versus capacity, since more capacity means more time under load, and more time under load means that more heat should be expected. If I did this, the Temp column would look something like this since all batteries start the test at the same ambient temperature. What you are looking at after the equal sign is temperature increase in degrees Fahrenheit per second of testing. I've created a space between a clear statistical divide:

SMC V2 150C 6400 = 0.258

SMC V2 20C 8000 = 0.335
Panther 70C 5000 = 0.336
Dinogy 80C 5000 = 0.340

SMC 60C 5200 = 0.350
SMC V2 60C 5600 = 0.361
Tunigy HD 60C 5000 = 0.363

HK Graphene 45C 5000 = 0.373

HRB 100C 6000 = 0.383
Roaring Top 70C 5000 = 0.391

Zippy 40C 6200 = 0.397
Hobbystar 100C 8000 = 0.397
Roaring Top 70C 5500 = 0.403

Hobbystar 75C 5200 = 0.504

This illustration tells me that although the SMC V2 20C 8000 ended up at 140*F, relative to time, capacity, and load, heat stacking was relatively lower than any of the other battery packs except for the SMC V2 150C. For example, the heat increases at 0.335 degrees F per second compared to 0.504 degrees F for the Hobbystar 75C 5200.
Last edited by Aeroplayin; Oct 01, 2020 at 07:40 AM.
Oct 01, 2020, 07:38 AM
Registered User
Aeroplayin's Avatar
I had to make some edits about since I should know not to do math in the morning before being fully caffeinated.
Oct 03, 2020, 08:31 AM
Registered User
Aeroplayin's Avatar

New from the Extreme Flight 85" Class


Here is some information about the new 85" planes from Extreme Flight. The pics below say it all so....
  • The columns are ounces, grams, and pounds
  • Substitute your own component weights
  • The wing areas are all pretty close and you can use 1392 square inches as the effective wing area (MAC x wingspan) and 1342 square inches using ((tip + root) * wingspan) / 2.
  • Keep the plane under 16.9 lbs if you like a cube loading under 9.0 oz/cu ft.
  • The 24x10 Falcon I have listed will do well on the motors I listed it with as far as both power and flight time with the listed capacity
  • The 22x11 Falcon C2E should be another option instead of the 22x10 PJN with the smaller motors
Last edited by Aeroplayin; Oct 05, 2020 at 07:50 AM.
Oct 03, 2020, 08:43 AM
Registered User
Fourdan's Avatar
Hi Jim
I don't see the HKIII 6430 reference by Scorpion (!?)
Is it a special order ?
Louis
Oct 03, 2020, 09:12 AM
Registered User
Aeroplayin's Avatar
Quote:
Originally Posted by Fourdan
Hi Jim
I don't see the HKIII 6430 reference by Scorpion (!?)
Is it a special order ?
Louis
Transferred the wrong motor name, so thanks for picking that up. SII-6530. I made the changes above.
Oct 03, 2020, 09:39 AM
Registered User
Aeroplayin's Avatar
Also, the weight of the DA-50 on stock is nothing to get excited about since spinning the 23x9 gas Falcon to 7150 RPM is only the equivalent of 4681W and the DM5327 can do that with a 22x10 PJN.

I didn't bother adding the StinGR to this mainly because the price is more like a Hacker Q80-8M. But the weight can be less than the GA6 with the same main pack to more flight time. I'd go with a 19T gear config with a 24x12 Falcon to only 104A at an easy 2:1 thrust and an estimated airspeed of 90 mph.

I have a 24x14 PJN that just got here and I expect only 123A at 6590 RPM at 44.4v for a 105 mph airspeed and about 45 lbs of thrust. This could be fun, but a bit overkill for an 85" plane that will probably perform better at 16.8 lbs RTF. I would need a 12S 5000mAh main pack for 5.5 minutes so the 113g prop and added capacity is now getting up there.... 18+ lbs but still 327 W/lb. Talk about powering through a high cube loading...
Oct 04, 2020, 08:08 PM
Ronaldo Nogueira
ronaldopn's Avatar
Quote:
Originally Posted by Aeroplayin
Here is some information about the new 85" planes from Extreme Flight. The pics below say it all so....
This is extremely valuable info, I wish we could have this from every other manufacturer directly on their websites.
Thanks for taking the time to organize and post the data, Jim.
Ronaldo
Oct 04, 2020, 10:24 PM
Registered User
Aeroplayin's Avatar
My pleasure, Ronaldo, and thank you for doing the same for all the other planes you posted here. And thanks to the other contributors here who helped to confirm the 85" class planes.... Rob, Greg, and Ben.
Oct 05, 2020, 12:13 AM
Use the 4S Luke
feathermerchant's Avatar
So all I see are columns of numbers. No headings. Am I supposed to know?
Oct 05, 2020, 12:29 AM
Registered User
Aeroplayin's Avatar
Add the column units.
Last edited by Aeroplayin; Oct 06, 2020 at 03:49 PM.
Oct 05, 2020, 04:46 AM
Registered User
Quote:
Originally Posted by feathermerchant
So all I see are columns of numbers. No headings. Am I supposed to know?
Column one is ounces, two is grams, three is pounds.


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question RC kits for experimenting with flight control systems SubZer0 DIY Electronics 15 Feb 25, 2015 04:15 PM
Wanted left wing for extreme flight yellow and black 74 yak hondaboy92hatch Aircraft - Fuel - Airplanes (FS/W) 0 Sep 29, 2011 10:18 AM
Discussion Extreme power systems & Royal Evo 12 rbehrends Radios 5 Oct 11, 2007 05:55 PM
Discussion Battery for Logo 10 - Thunder Power "eXtreme" 5S 4600 or Flight Power 5S 3700? WeatherB Electric Heli Talk 6 Jan 25, 2007 11:29 PM