Notices
Ask the Expert Sal - Electric Airplane Advice Here is your chance to ASK SAL, the expert for all your electric flight related questions. If you are not Sal, please do not answer questions in this forum.

Battery/ESC question

Old 03-24-2024, 04:39 PM
  #1  
Real2You
Thread Starter
 
Join Date: Jul 2009
Location: Valley Springs, CA
Posts: 539
Likes: 0
Received 5 Likes on 4 Posts
Default Battery/ESC question

Hello, I picked up a Tunnel Vision profile airplane and it says a 1.60 2 stroke is a good engine. My question is if I want to go electric and I need a 10s-12s setup...if I put two 6s Lipos together to get the 12s does that mean I have to get an ESC that will go up to 12s? The reason I ask is I saw a person on another forum that had a 100 amp ESC on his motor and he had two 6s Lipos together but the ESC was only rated for 6s. How does that work or does it? Thanks.
Old 03-25-2024, 10:12 AM
  #2  
LLRCFlyer
Senior Member
 
Join Date: Feb 2023
Location: Corryton, TN. Fly at Lucky Lane RC Club
Posts: 158
Likes: 0
Received 22 Likes on 20 Posts
Default

To get a power level of 3 or 4 HP requires higher voltage to keep the amperage down to a workable level. You are going to a higher voltage-lower KV motor and will be connecting the batteries in series, thus doubling the voltage. This will definitely require an ESC rated for 12S batteries (50.4 volts). Do not apply a higher voltage than for which the ESC is rated.
Old 03-25-2024, 01:11 PM
  #3  
Real2You
Thread Starter
 
Join Date: Jul 2009
Location: Valley Springs, CA
Posts: 539
Likes: 0
Received 5 Likes on 4 Posts
Default

Thanks! That answers my question. Now it's time to get that bird in the air!!
Old 03-25-2024, 05:59 PM
  #4  
LLRCFlyer
Senior Member
 
Join Date: Feb 2023
Location: Corryton, TN. Fly at Lucky Lane RC Club
Posts: 158
Likes: 0
Received 22 Likes on 20 Posts
Default

In case you have not used high-voltage-high-amperage ESC's before, just know that they come in two forms. One is the standard configuration that includes a built-in battery eliminator circuit built in to power the radio. This is convenient, but the down side is that the BEC may not be sufficient to supply the power needs of all the servos, or if there is a problem with the battery/motor/ESC, the built-in BEC could go dead and then you have no radio control what so ever. The other style is the "OPTO" which uses a separate battery to provide power only to the motor. The radio and servos must be driven from a separate power source (a second battery or battery/voltage regulator combination). Altitude Hobbies has some Hobbywing ESC's for under $140 that might work, both standard and OPTO. Many people choose to go the OPTO route when they start flying really large electric models in order to increase the reliability of the radio. That way they can make a controlled landing if the ESC/motor/battery should fail. Buddy RC and Chief Aircraft have some Castle Creations high-voltage ESC's but they start at nearly twice the price of the Hobbywing ESC's, but they do include telemetry capability.

https://www.altitudehobbies.com/coll...a-hv-esc-6-14s

https://www.buddyrc.com/products/cas...-brushless-esc

https://www.chiefaircraft.com/cse-phxedgehv120.html

I have ordered from all three of these companies and have received excellent service from them.
Old 03-25-2024, 06:18 PM
  #5  
Real2You
Thread Starter
 
Join Date: Jul 2009
Location: Valley Springs, CA
Posts: 539
Likes: 0
Received 5 Likes on 4 Posts
Default

Thanks for the information. That's very good info I didn't know. Now I have to decide if I should electric or nitro or gas I guess. Being a profile you have to be creative where you put everything and consider the CG. I guess that's what makes this hobby fun, going through all your options and then putting it all together to see the final result.
Old 03-26-2024, 05:57 AM
  #6  
LLRCFlyer
Senior Member
 
Join Date: Feb 2023
Location: Corryton, TN. Fly at Lucky Lane RC Club
Posts: 158
Likes: 0
Received 22 Likes on 20 Posts
Default Which power type?

You say you are now considering electric, glow and gas for power options. A typical 1.60 size 2-stroke glow engine (as recommended by the kit) will produce anywhere from 3 HP for a Super Tigre S3000 to 3.7 HP for an OS or Moki engine. These big glow engines drink lots of expensive glow fuel ($25-30 per gallon) and you can plan on getting about 6 to 8 ten-minute flights per gallon (with lots of oil residue) when flown hard. I would suggest you consider electric or gas power for this size model. A 30cc gasoline engine will produce about 3.7 HP. DLE makes a nice 30cc single cylinder engine rated at 3.7 HP ($330). The RCGF Stinger 30cc twin cylinder engine ($390) is also rated at 3.7 HP and is very smooth due to the opposed piston configuration canceling out a lot of vibration. If you want something closer to the 3 HP Super Tigre S3000, consider the 3.1 HP RCGF Stinger 26cc single cylinder engine ($275) which is almost a direct drop-in replacement (mine turns an 18x8 prop at 7,560 rpm). The gas engines may seem expensive, but not when you consider the cost of big (6000+ mah capacity) 6S LiPo batteries. If you want to fly multiple flights at the rate of 2 flights per hour using 2 batteries per flight, you will need at least 2 (maybe 3) sets of batteries to do this. This means buying four (or 6) batteries at $100 each and then plan on replacing them every few years. Depending on the capacity (wattage) of your charger, it will take anywhere from 45 minutes to an hour and a half to recharge the batteries for the next flight. A high capacity charger like the Hitec RDX2 1000 AC/DC Dual Port Charger that can charge two 6S-6000 mah batteries simultaneously at a 1-C charge rate will cost about $280, but could also charge 4 batteries at once if a parallel balance board is used.

I generally don't use large 2-stroke engines or large electric motors. I usually find gasoline engines are more cost effective for my models weighing over 10-12 pounds when noise restrictions are not a prohibitive issue.

Last edited by LLRCFlyer; 03-26-2024 at 06:16 AM.
Old 03-26-2024, 08:04 PM
  #7  
Real2You
Thread Starter
 
Join Date: Jul 2009
Location: Valley Springs, CA
Posts: 539
Likes: 0
Received 5 Likes on 4 Posts
Default

I actually just purchasesd a castle creations 120 ESC and a specktrum Avian 6362 motor....I also have an Eflight Power 160 I think might work also. I have other planes that use 6S 5000's that I have 4 or 5 of those batteries so I have some options. The power 160 is only rated for 10S....so I would need to get 5S batteries to make the 10S. I would love to go gas but I need to figure out how to mount the engine being that it's a profile with the engine cut out in the front 2" x 4". I'm sure I can figure something out and mount it in a way that would be strong. Building something this big is all new to me so I am learning as I go. Thanks for the information.
Old 03-27-2024, 11:37 AM
  #8  
LLRCFlyer
Senior Member
 
Join Date: Feb 2023
Location: Corryton, TN. Fly at Lucky Lane RC Club
Posts: 158
Likes: 0
Received 22 Likes on 20 Posts
Default Gas Mounting Options

A possible gas mounting option is to use a beam-mount engine like the RCGF Stinger 26RE, See the link below. It should be easy to mount it the same way as the recommended 1.60 glow engine.

https://www.rcgfusa.com/product/stinger-26cc-re/
Old 03-27-2024, 02:21 PM
  #9  
Real2You
Thread Starter
 
Join Date: Jul 2009
Location: Valley Springs, CA
Posts: 539
Likes: 0
Received 5 Likes on 4 Posts
Default

Do gas engines work well for 3D type flying? I looked at that Stinger and I would only have to cut 1/4" off the top and bottom of the front opening for the engine.
Old 03-27-2024, 04:31 PM
  #10  
LLRCFlyer
Senior Member
 
Join Date: Feb 2023
Location: Corryton, TN. Fly at Lucky Lane RC Club
Posts: 158
Likes: 0
Received 22 Likes on 20 Posts
Default Gassers for 3D?

Gas engines can work very well for 3D. The key is to make sure the thrust to weight ratio is sufficient to briskly accelerate the airplane up from a hover. For example, my 18 pound Ultimate hovers nicely at 2/3 throttle powered by a 26 pound thrust Brison BA32 (53cc) engine. If the thrust to weight ratio is at least 1.4 or greater (up to 2.0), it will probably work well for 3D. Go to a club where large (i.e. 25% scale or larger) 3D models are flown and you will find very few 3D electric models over about 12-15 pounds, Yes, there are large electric 3D aircraft, but the vast majority will be gassers. As for your model, I cannot recommend an engine for 3D without knowing its all-up weight. If your model is listed at 10 to 11 pounds, then the RCGF Stinger 26RE should work well with its claimed thrust of 17.68 pounds. It would definitely fly it at 14 pounds, but the 3D performance would no longer be sparkling. I have collected as much data as I could find on various gas and glow engines concerning power, thrust, weight, propellers, oil mix, cost, mounting type, etc. and put them in a spread sheet. That data is included in the attached PDF file. The engines named in red type are ones that I actually own and for which I can vouch for the static rpm data. Everything else is data I collected from the internet for what ever it is worth. You might find it interesting to compare the RCGF Stinger 26RE against the Super Tigre ST3000 (30cc. 1.80 cu inch) glow engine since the ST3000 should be sufficient to fly your airplane. The performance specs are very similar but the Stinger is lighter. There is one other noteworthy item. Unlike electric motors, gas engines must be carefully broken in and properly adjusted. This can take some time. One needs to make sure the engine has enough flight time to be considered broken-in, the carburetor settings are correctly set and the throttle response is crisp before starting any serious low altitude 3D maneuvers. For the 26 cc Stinger RE, this would be about 2 or 3 gallons of gas mix or about 5 or 6 flight hours. It normally takes well over 20 hours to totally break-in a gas engine to get its peak performance. However, unless it gets poked into the dirt or run without oil, it should last for a couple hundred hours, or longer. If you are considering the Stinger, go to the RCGF USA website and see my (David Boyll) review of the Stinger 26RE.

For your model, it sounds like you would need a 26 to 30cc engine, but most engines above 26cc switch to stand-off mounts which can be problematic on a profile model. If the Stinger 26 doesn't make enough thrust, then you are probably back to an electric setup. When going for a spirited 3D electric setup, you should be looking for a power to weight ratio of 200 watts per pound. Decisions, options, decisions, dilemma...... Enjoy!
Old 03-27-2024, 04:49 PM
  #11  
LLRCFlyer
Senior Member
 
Join Date: Feb 2023
Location: Corryton, TN. Fly at Lucky Lane RC Club
Posts: 158
Likes: 0
Received 22 Likes on 20 Posts
Default

See attachment which would not post with Google Chrome
Attached Files
File Type: pdf
Gas Engine Specs.pdf (417.6 KB, 5 views)
Old 03-27-2024, 08:18 PM
  #12  
Real2You
Thread Starter
 
Join Date: Jul 2009
Location: Valley Springs, CA
Posts: 539
Likes: 0
Received 5 Likes on 4 Posts
Default

Wow...thanks for all the good information. I need to figure out the weight of the plane. I was reading a post on one of the forums that came up when I googled the Tunnel Vision and one guy had a OS 1.60 and I remember him saying the final weight was around 13 lbs. I was kind of using that as a weight to get options. I know one thing...I am learning a lot, so I will have a good understanding of everything when I do put it all together.
Old 03-28-2024, 10:46 AM
  #13  
LLRCFlyer
Senior Member
 
Join Date: Feb 2023
Location: Corryton, TN. Fly at Lucky Lane RC Club
Posts: 158
Likes: 0
Received 22 Likes on 20 Posts
Default OS 1.60FX specs

I found the specs below on the OS 1.60FX. If it really takes 3.7 HP OS 1.60FX to fly the Tunnel Vision in 3D, then the Stinger 26RE at 3.1 HP might struggle a little during serious 3D, but should be fine for sport flying. It all depends on what it weighs. Of course, the OS 1.60FX was one of the stronger running 1.60's. The Stinger 26RE and the OS 1.60FX weight very nearly the same (less than an ounce difference).

This is the OS Engines 160FX 1.60 ring glow engine, with 60F carburetor and included OS E5010 Muffler.

Specifications:
  • Displacement: 1.60 cu in (26 cc)
  • Bore: 1.32 in (33.6 mm)
  • Stroke: 1.16 in (29.6 mm)
  • Practical rpm: 1,800-10,000
  • Output: 3.7 hp @ 9,000 rpm
  • Weight: 32.6 oz (925 g)

Recommended Props:
  • Aerobatic: 15x12, 15x13, 15x14, 16x10, 16x11, 16x12, 16x13, 16x14, 16.5x10, 16.5x11, 16.5x12, 16.5x13
  • Sport: 17x10, 17x11, 17x12, 17x13, 18x10, 18x11, 18x12
Old 03-28-2024, 07:47 PM
  #14  
Real2You
Thread Starter
 
Join Date: Jul 2009
Location: Valley Springs, CA
Posts: 539
Likes: 0
Received 5 Likes on 4 Posts
Default

I'm probably going to give electric a try. I will definately weigh it out before so I know exactly what kind of weight I'm working with. If it comes in at a significantly lower weight than I expect which is around 13 lbs...I will go the Stinger 26 route.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.