dwbebens

Archie;

I'm impressed with the performance of your Q-500 electric conversion per your video.

If the off-the-shelf 1,000 Watt-min limiter will be enough energy for a heat using the relatively inexpensive power package that you used, then we may very well have a new event. I know for a fact that electric racing can quickly get-away-from-you as far as expense and speed creep goes. The limiter, as you say, will take equipment out of the equation leaving some good "mano-a-mano" competition. I am strongly in favor of the limiter idea.

I'd be interested in promoting and having electric Q-500 racing in our area once you guys have settled on the parameters. Also, I'm interested in Don's idea of using the Wingman airframe, though two new electric classes in that size range might not be supported as much as one event would be. I'd like to see only one new (larger) class of electric pylon racing for a start. Then, see how it goes. You guys hash-out the rules and do the R&D. Keep us informed. I'm in!

Doug Bebensee

Iceman67

Doug,

The goal of this conversion was to make an EP Q-500 go as fast as a TT40 pro powered Q-500 on the long course as we fly it here in the Midwest as a plug and play system for the same cost and same weight. That goal is close to being accomplished. The longer motor, higher Kv, and 9 x 7.5 APC "E" will seal the deal and accomplish the goal. Now, I think the monster needs to be controlled with a set of guidelines. If there is interest in this type of event, then we need to see where the interest lies. Do we keep it with the power system as flown to keep the speeds down as a beginner class, or use the Wingman with the same larger power-system and control it with props?

My suggestion would be the following:

Wingman II event be limitied to the 35-48-1100 Turnigy SK Aerodrive XP Out-runner motor, 10 x 5 APC "E" prop, and 4S1P 20C 2500 MaH Lipoly cells. Fly this event on either AMA 540-B (2) pylon course or AMA short course. (Min weight 3.5lbs)

EP Q-500 to use exsisting legal Q-500 airframes with wood wings like 424. Use a 1000 watt-min limiter, exposed motor, 9" min prop dia, and fly on AMA long course. Same commercially available non modified prop rule as 424 and 428. Weight to be the same as 424 & 428 (3.75lbs) Might also specify only out-runners as to keep the cost down.

Now, if clubs are interested in flying the EP Q-500 and can't support the course requirements to AMA safety standards, then a provision for AMA540-B (2) pylon course be used and limit to hand out props which I would suggest the 9 x 6 APC "E". A motor requirement might also be needed to keep speeds down in the 100 mph or less range for that.

Any thoughts? Could we have something here?

racerxwest

Could you post the approx. cost to convert from the TT40 to elect and a list of items needed> Thanks

Iceman67

Here is the list you requested.

Total powersystem cost:
Electrifly Motor Medium Mount $16
Motor $28 (Turnigy SK Aerodrive XP 35-42-1000)
ESC $43.89 (Turnigy Plush 60Amp)
Battery $32.83 ea (Rhino 4S1P 20C 2350)
Balancing Li-Poly Charger $27.68 (Hextronik 8080) note:this is a nice cheap unit with built in balancer for the batteries.

Note, I will be testing a new more powerful system using a 35-48-1100 KV motor. With the current system listed, the airplane is around 80-90 mph. I hope to have more data soon. I am trying to get an police officer friend of mine to come out and radar gun the EP Predator to see how fast it's going.

Thanks for your interest. Let me know how it goes.

Take care,

DonStegall

My Feedback: (1)

Here are the links as provided to me by Archie

Motor Turnigy SK Aerodrive XP 35-42-1000
http://www.hobbycity.com/hobbycity/s..._1000Kv_/_605w

Motor mount
http://www3.towerhobbies.com/cgi-bin...?&I=LXLCL4&P=0

Controller Turnigy Plush 60
http://www.hobbycity.com/hobbycity/s...eed_Controller

Battery Rhino 20C 4S 2350
http://www.hobbycity.com/hobbycity/s...0C_Lipoly_Pack

Charger Hextronik 8080 (cheapest)
http://www.hobbycity.com/hobbycity/s...Charge_Capable

Note that HobbyCity has a Zippy 2200 mAh battery for about the same price and same weight ... http://www.hobbycity.com/hobbycity/s...00mAh_4S1P_20C

Iceman67

The 35-48-1100 came this weekend. I will be going to the field tonight after work. I also bought some 9 x 7.5 props to try. We'll see how it goes. I went to the Dualsky site and see that they rate their motors the same as Turnigy does. Going to higher cell count makes the rpm and power come up quick, but the weight comes with it. I want to try to stick with 4S for now. With the Viper starting out heavy out of the box, I would stay with the 4S 2500's and go with the 35-42 or 48 length motor as close to 1000-1100 Kv and use a 9 x 6 or 9 x 7 prop. You will outrun most things on the field without tuned pipes or turbines. LOL

I'll post the results tonight when I get back. I got the Eagle Tree in it this time to get some inflight data as well.

Take care,

Iceman67

Okay, flight session #2 provided my first onboard flight data. I used a TGS 9 x 7.5 prop on the 35-48-1100 on 4S 2350's. What I found out is what I expected. It wasn't enough prop. The speed was about the same as the shorter motor, but the current was down. This points to more available torque from the longer motor. I then changed the timing to high on the Pheonix ESC and it ran smoother and used even less battery. So, it is off to buy more props. The 35-48 certainly runs more efficient than the 35-42. Next set of tests will use the 9 x 7, 9 x 7.5, ad 9 x 9 APC. I may even try an 8.8 x 8.75 APC. The TGS prop was not very impressive. This weeks weather is looking promicing for more flight testing. I'll keep you posted.

I have attached the Eagle Tree Flight Data report. Estimated in flight speed is 94mph.

Take Care,

Iceman67

Today I got some flights in between the rain storms. I flew using an 8.8 x 8.75 & the 9 x 7 APC "E". The flight with the 9 x 7 is after the second bar on the Data logger file. It is very close, but not there yet. It was about the same speed with both props. The 8.8 x 8.75 is my 428 prop of choice, but it works much better @ 20,000 than @ 13,000. The 9 x 7 "E" pulled much harder and accelerated much better. Hopefully the 9 x 7.5 & 9 x 9 APC "E" props will be here this week. The onboard data collector is a great tool. There is no substitute for live information.

Take care,

Iceman67

Took advantage of some great spring weather this weekend and flew the EP Q-500 (6) times. I removed the system from the Predator and installed it on my Composite V-Raptor. The plug and play idea worked out great. The V-Raptor flew great and it was faster than the Predator. My camera man/boy is in Florida for spring break, so I hope to get video of it next week.

The system now has (12) flights on it and it has proven to be very viable. Who is interested in racing EP Q-500?

racerxwest

So what would be the final total set-up that you would recomend?

Iceman67

Total powersystem cost:
Motor $33 (Turnigy SK Aerodrive XP 35-48-1100)
ESC $44 (Turnigy Plush 60Amp)
Battery $33 (Rhino 4S 20C 2350)
GP med Electrify mount $16
Total cost $126

You will need to get a balancing Li-poly charger capable of charging 4S packs if you don't have one. There are many on the market. HC has several with built in balancers. I use a Triton 2 with equinox balancer and a Hextronic 8080 from HC. Both work great. The 8080 was $27 from Hobby city.

Take care,

Iceman67

My new APC's came in finally and I was able to go and fly last Thursday night. Finally had a few guys at the field so it was nice to have some company out there. I have attached the Eagle Tree data collected from the flight with the 9 x 7.5 & the 9 x 9 APC "E" props. Both flights were virtually identical in speed thus pointing that the battery has nothing more to give. This could be a great way to limit the power instead of using a watt limiter. I think out of all the props tested, the 9 x 7.5 showed the best bang for the buck. The power-system is running very efficient at these power levels and not overloaded at all.

So for my suggestions for EP Q-500, I would suggest the following:

-Any legal 424 airframe
-3.75lb minimum weight
-35-48-1100 Turnigy SK motor (must be exposed)
-AMA safety nut or spinner to be used.
-2500 maH 4S pack (20C) max pack size
-APC 9 x 7.5 "E" prop hand out @ race

Safety Requirements
An external arming plug to disarm the system while aircraft is still assembled. This is a must for safe operation. All other AMA safety rules that apply to Q-500 racing to apply.

I feel this event would be a great fit for AMA short course, AMA long course, or for AMA540-B (2) pylon course. I am bringing my Composite Raptor up to Michigan this weekend to see if I can stage a race with my brother and his 424 with a TT40 pro. I hope we get the weather to stage and video a race. I still think this EP Q-500 falls a bit short of a 424 with a TT40 pro, but not by much. It would be a great entry level event.

Any thoughts?

Take Care,

BarryReade

My Feedback: (1)

In trying to level the playing field and make just the thumbs that are the variables I think saying all 4s 2500 mah 20C batt are the same is like saying all pigs are the same. I think there is a very large variable in batteries and just because a battery says all those things and cost more than any others doesn't make it the most efficient, highest capacity, or highest amperage draw battery of the group. Even within the same manufacturer you will find wide variances and a knowledgeable person will find the best battery and will run it appropriately. [X(] As usual the folks that do their homework will be running at the front of the pack and those that don't will be also ran's. I am not opposed to EP Q 500 racing as I like my elec planes. I like the turnigy equipment and the Zippy family of batteries. I just ordered 4 GS Q 500's and plan on making one of them electric. I was thinking of the SK 42-50 motor which weighs about 2 oz more than the 35-48. I think if you try and be to restrictive the people you want to come out and fly won't because they have to be to specialized. You might have different classes with a breakout time to move up to the next faster class like the RCPRO Warbirds use and keep the equipment restrictions to a minimum.[8D]

Iceman67

Barry,

You bring up many good points about how to govern this. My original idea of using the 1000 watt limiter is the best way because it takes all the variables out. My thought of trying to limit using the small batteries is a stretch, but I have proven that the Rhino 20C 4S 2350's are only capable of sustaining around 600 watts. The change from the 9 x 7.5 to the 9 x 9 used more power, but gave no more speed which points to limiting returns from the battery.

Using the limiter would allow the use of any power-system and then would bring it back to the thumbs. I do believe that the 1000 watt limiter is enough especially if we keep it at an entry level event as it should be. But these do cost $50 ea.

Going to the 42-50 means you will have to use at least 5S but probably 6S to get any rpm. I have been having that problem with the 35-48-1100. The 42-50 doesn't have much Kv so that is where you will run into trouble if your intention is to run 9" props.

Bottom line is that there are many motor/ESC/Battery combos that will work in this event. Settling on one system would need to be a local deal and would greatly depend on availability of product. I look forward to hearing about your testing with the 42-50.

Take Care,

BarryReade

My Feedback: (1)

Archie, I am using the SK 42-40 600W motor and on the Rhino 20C 4S 2350 I am pulling 611 watts on a 14X7. Maybe you should consider using a different airframe and not try to match the 424 planes and their performance. The RCPRO Warbird series is really interesting as it doesn't limit the airframe other than wing in. to displacement of the engine and has three time brackets that one can run in. If you run faster that the fastest time allowed for that class you break out and get a "0" for points. I am not saying to do that but, like the Club 40 racing maybe you should consider an airframe like the [link=http://www.rcuniverse.com/magazine/article_display.cfm?article_id=1086]Wingman II[/link]. That would be a great Sport flyer and could be used for an E Pylon class. I think Don Stegall recommended that to me when I was thinking of getting an E pylon class going. I have that plan on my list of planes to get eventually. You might even consider going with a trike landing gear as newbies tend to have problems with tail draggers. Just some thoughts that came to mind. 75 mph racing can be exciting and you don't have to go 120 mph to have fun racing.

Iceman67

Well, the EP-500 experiment is complete. I believe it is a viable solution to an EP entry level racing event using airframes that are readily available and many racers have on hand. Cost involved is no more than the glow power to make the conversion affordable.

I guess the next place to go would be to go to an electric sport racer. I have an LA racer and am going to assemble it to be capable of using the TT40 or the same conversion I used in the EP Q-500. I would change to an 11 x 5.5 prop and go with it. I hope to get the LA Racer together in the next couple of weeks.

As far as an electric racing event goes, I guess the interest level needs to be weighed to see where an event like this could be successful. Electric racing brings a lot to the table. If governed correctly, it could be a bunch of fun and very competitive. What I don't want to see is that for each class of racing, we have a brand new airplane with another set of requirements. We already have capable airframes out there that can be converted. For example, the QM-15 class that was replaced by Q-40. There are several designs out there that could be easily converted to electric power very cheap. Those airframe are small, but they fly great and they would be fast enough to keep people interested. We have Q-500's and we have Q-40's, and we even have Form-1's. A Q-40 conversion could be done with the same expense level as the EP Q-500 and be a bit faster. The Form-1's as well would be good conversions because there is a bunch of room in there for batteries. Another example would be the Club 2000 flown in Europe specifically E2K which is very successful. It is a smaller version Quickie airframe already with requirements that could be flown here without having to write rules.

I think the Wingman II is a very nice ARF that would make for a good racing class, but I think that if you are asking people to buy a whole new airframe and set-up to fly electric racing, that interest will not be there.

Note to self: There is a rumor that the NMPRA is evaluating a new EP racing event utilizing an all new airframe as well. I don't have specifics, but maybe someone who does could chime in.

Take Care,

BUDMAN27

Iceman67 You are the man

tIANci

My Viper's firewall started to peel off after using the Jett Q500 and so now I think its a good time to go EP on it. I was thinking, will a 4S set up not be too much for a 35-48 motor? Did it not get too hot pulling that many amps and turning such high RPMs? I thought they were only good for like 40A-45A. I tested the DualSky 3548-1080KV on their motorcalc with 4S and a 8x8 prop, gave 100 mph @ 40A, seems decent to me.

Iceman67

I'm not sure about the Dualsky, but the Turnigy SK 35-48-1100 is rated for 800 watts. I have flown it at over 650 watts on 4S with no issues. My in flight current is from 45-50 amps. The motor comes down cold. The best prop for the 4S 2350's has been the 9 x 7.5 APC. The 9 x 9 increased the current, but not the speed. I think it accelerated better with the 9 x 7.5 too. Now, for all out speed in a shallow dive, the 9 x 9 was noticeably faster, but again, we don't race that way. Please see the Eagle tree data above for specific flight performance numbers. If you went to a slightly larger 3200 pack, both the 9 x 9 would and 9 x 7.5 would go a bit faster because the voltage drop would be less thus the watts would go up. This would however increase weight and cost significantly.

Bottom line, you won't be disappointed. It is fun to fly. I have (5) packs and I used them all last week in one flight session. It has unlimited vertical with either prop. I flew some very basic pattern with it the last three flights and got almost 4 minutes of flight time with some throttle management.

Please note: I am looking for a 5S 2500 pack to test. I will try to get one @ the Toledo show this weekend if the price is right.

Take Care,

Iceman67

Well, we raced off this weekend EP Q-500 vs TT40 424. We sent the TT40 off @ 16,300 on the APC 9 x 6 & we raced. The speed was off by about 15 mph. We flew about 20 laps getting a good look at the speed difference. It is significant, but the EP held its ground. The predicted speed from my Eagle tree plots was around 110 mph and that is a good assumption of what it was doing.

Next step is to take it to 5S and see what it does to the speed. The 1000 watt-min limiter would be a great place for a sport race, but well short of what it needs to be competitive with a 424 racer. I am looking for affordable 5S 2350-2500 packs right now to see how quickly I can test this. I would still use the 9 x 7.5 prop, motor, & ESC, just add a cell.

Now on the flip side, the current set-up may be very good short course/(2) pole set-up.

Testing to be continued.......

458ronnyb

Read your item in thread, where you referred to Speed 400. I recently bought a Swallow 400, with the necessary parts. I know absolutely nothing about electric and would like to learn. Do you have any suggestions as to where to look. I have the craft assembled but cannot figure out the settings on the ESC.

Iceman67

Let me know what type of motor, controller, and battery you have. I would assume brushless?

Big tip would be to keep it light!!! 16 ounces and around 150 to 200 watts of power would be a bunch of fun.

tIANci

Iceman ... lemme see if the DS 3548 motor can handle it. I shall keep t 4S and I still have 3 FP packs of 2,500 and just ordered the FlightMax 30C 2,500s. I think 5S will be a hoot! Now time to remove the engine from my Viper.

458ronnyb

Iceman76
I have an inrunner brushless motor. The only identifications I can find are: KV/3200Rpm/V, and the letters: HXY. This means absolutely noithing to me as I am new to electrics. The speed controller is an E Flight 40A and the battery is Zippy 2500 mah 3 cell Lipo I plan to run a seperate receiver battery to help balance the plane. Any help would be appreciated.

Ronny B

458ronnyb

Iceman, Just found more motor numbers: OK-B2856 (380XL). Hope this helps, I don't know what brand it is but it came with the Swallow, from China. Buy the way, the swallow weighs in at 23 OZ.

Thanks,
Ronny B.