HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Mar 25, 2005, 08:43 AM
Registered User
Santiago, Chile
Joined Mar 2003
168 Posts
formosa problem almost solved

well, i found a website were it says how to modify the LVC of your ESC, i did it and it works, not perfectly but i think itīll do. Now the ESCīs LVC activates at 6.2V. not to bad... Now the thing is to lower amp draw....if i go full throttle, the motor shuts in a few seconds...when I havent even reached the top of the throttle stick, it comes to 6.2V and shuts....so i thought....I have a eps.350D and that might draw less amps....now im asking for your help again...lol. I think a eps-350D with a 9070 draws less amps than the 350B that comes with the formosa....

http://homepages.paradise.net.nz/bha...cs480_lvc.html

Not hard to do....just be patient...iīm 16 years old and i dont have much experience and i did it so you can do it. It is a little small though lol
chileno is offline Find More Posts by chileno
Reply With Quote
Sign up now
to remove ads between posts
Old Mar 25, 2005, 10:42 AM
Registered User
Santiago, Chile
Joined Mar 2003
168 Posts
well since nobody cares...iīll just keep writing....I installed the EPS-350D with a 8060, and the performance was very poor, it barely flew.....and then I changed the prop to a 9070....and flew well, but not good...I think maybe thwe 350C would work great
chileno is offline Find More Posts by chileno
Reply With Quote
Old Mar 25, 2005, 11:21 AM
Registered User
txfly's Avatar
frisco,tx
Joined Oct 2003
1,911 Posts
go brushless.
txfly is offline Find More Posts by txfly
Reply With Quote
Old Mar 26, 2005, 11:28 AM
Registered User
Highland, IL
Joined Sep 2004
14 Posts
Yes, Brushless
sk8nhl is offline Find More Posts by sk8nhl
Reply With Quote
Old Mar 26, 2005, 11:53 AM
ElectriGlo Pilot
Trogdor's Avatar
Ashburn, Virginia, United States
Joined Dec 2003
878 Posts
Quote:
Originally Posted by chileno
well, i found a website were it says how to modify the LVC of your ESC, i did it and it works, not perfectly but i think itīll do. Now the ESCīs LVC activates at 6.2V. not to bad...

http://homepages.paradise.net.nz/bha...cs480_lvc.html
That's pretty neat. When I started in electrics 1.5 years ago, I was really into the electronics of chargers, escs etc. I built a couple nimh chargers from kits and bought a book on intro electronics that went over what all the different doodads do. I don't think I'll try this but it works as I'd expect based on my knowledge.

Did you use the resistors with the tight tolerances?
Trogdor is offline Find More Posts by Trogdor
Reply With Quote
Old Mar 26, 2005, 12:04 PM
Crash Master
Gene Bond's Avatar
Indianapolis, IN
Joined Sep 2001
16,632 Posts
chil: It sounds like you are trying to use too much motor for the battery. I don't know what battery you have, but drawing it down to 6.2v at full throttle sounds weak to me. Seems to me it should be more like 7+ volts.

The 'D' ratio gearbox is meant for huge props. I swear my Formosa came with an EPS350C-C... yup, just checked. It works perfectly on a 9070RS prop with 2s 830-1200, or 7-8xKAN650... If you have a 'B' ratio, you got the wrong one with the kit. It will work with an 8x6 or so prop, but not with the performance you want.

Double check the marking on the spur gear, and let us know what pack you are running. We can help you from there.

DO NOT go brushless. At least not until you are sure you like the plane. It flies perfectly right out of the box. If you want more performance or get tired of buying cheap can motors for more than they are worth, then it will be worth the investment. For now, spend the extra $100 on your girlfriend... It'll be worth it
Gene Bond is offline Find More Posts by Gene Bond
Reply With Quote
Old Mar 26, 2005, 12:20 PM
Registered User
Santiago, Chile
Joined Mar 2003
168 Posts
Yes, it came with a eps 350c "B" gear and I also Have one with "D" gear laying around, well the thing Is i am using the GWS 2s 1300 mah (7.4V) and even when in the little box it says it has 10C discharging rate, after flying it and doing some reading in the website, it is 6C, so im asking for some help because I have tried several things:

"B" gear with 9070 SF prop: good performance but battery cant handle it (at 75% throttle batt voltage drops to 6v.

"B" gear with 8060 SF prop: not big differences in performance, longer flightīs but battery still cant handle it (at 80% throttle batt voltage drops to 6v.

"D" gear with 8060 SF prop: Very poor performance, battery handles fine. (at full throttle, battery voltage drops to 6.7V)

"D" gear with 9070 SF prop: Better perfomance, at least the plane can cruise and roll, but definetly not what I want.....the plane cant loop....even with a dive.

The thing is I need to find the correct combination B, C, D according to what you have said....must be C. and prop, wich gives me similar thrust that gives the B with the 9070 and 8060, but with an amp draw of less than 7.8 amps, cause the battery is 1300mah and it is 6C so thats the limit.

Well, I hope you can help me because I have been trying and trying.....and at the moment things havenīt worked out perfectly.....
chileno is offline Find More Posts by chileno
Reply With Quote
Old Mar 26, 2005, 12:25 PM
Registered User
Santiago, Chile
Joined Mar 2003
168 Posts
nice....now it shuts off at 6.0V the ESC works great I used 5% resistors....those were the better I could find...and the capacitor I used a ceramic one, not an (SMD) a lot bigger than the one in the PIC....mine is like 0.5cm*0.5cm.

Now the thing to solve is thething I wrote in the post above this one
chileno is offline Find More Posts by chileno
Reply With Quote
Old Mar 26, 2005, 12:39 PM
Crash Master
Gene Bond's Avatar
Indianapolis, IN
Joined Sep 2001
16,632 Posts
I feel for ya, man. It just burns my butt when there's something missing or wrong in the box of something I buy. I mean, if I make that mistake, I lose money or a customer.

I haven't measured mine, but acording to GWS's chart: http://www.gws.com.tw/english/produc...em/eps350c.htm the 9070RS on the EPS350C-C should be 8a @ 7.2v, so you should be good to go. With the B ratio, I'd shoot at 8060RS with less performance.

If you bought it locally, I'd take the EPS unit back and have them get you the right one. It's the manufacturers fault, after all. It looks like GWS has changed the specs, though: http://www.gws.com.tw/english/produc...em/eps350c.htm to use an EPS350C-D and 1147RS and is calling for a 711.1v 1050mah pack I'd guess they mean a 3 cell pack, though... But that combo doesn't show in the charts, and is probably overloaded Another half-baked GWS attempt. I would run the D on a 1047RS and 3 cells, myself.

You might try a 1080RS on the D you have, to see how it goes. It'd be closer to the 9070RS on the C than what you have tried.
Gene Bond is offline Find More Posts by Gene Bond
Reply With Quote
Old Mar 26, 2005, 11:35 PM
Registered User
lovefool's Avatar
Japan
Joined Mar 2004
176 Posts
Gene - GWS seems to change the gear unit for Formosa. I bought a Formosa last November, that came with 'B' gear. The manual has a piece of paper to correct the gear and prop. Mine came with GW/EPS-350C-BS EP8060/EP9070. Anyway I will go with brushless tho.
lovefool is offline Find More Posts by lovefool
Reply With Quote
Old Mar 27, 2005, 02:07 AM
Registered User
Santiago,Chile
Joined Oct 2004
97 Posts
Que tal compatriota ? lo has probado pa que corte a 9 volt ? esto es para un pack de lipo de 3 celdas, gracias por tu contribucion.
acrored is offline Find More Posts by acrored
Reply With Quote
Old Mar 27, 2005, 07:35 AM
Crash Master
Gene Bond's Avatar
Indianapolis, IN
Joined Sep 2001
16,632 Posts
Quote:
Originally Posted by lovefool
Gene - GWS seems to change the gear unit for Formosa. I bought a Formosa last November, that came with 'B' gear. The manual has a piece of paper to correct the gear and prop. Mine came with GW/EPS-350C-BS EP8060/EP9070. Anyway I will go with brushless tho.
Interesting. Mine was one of the 'Early Bird' Program planes. I paid a big premium for a prototype or Beta Kit... At the time, everyone felt the EPS350C-C / 9070 (also came with 1060HD) was the right combination. The problem some had was using AAA cells that wouldn't put out the 8a or so needed for the motor. I remeber using 8x800 (5/4aaa), and being happy. I then tried 2s and 3s ET1200's, and it was OK, but the 3s was too much for the motor to last long, and the 2s was too light for the plane... It just didn't have the inertia to fly as well as with a heavier pack. When I tried the 8xKAN650, I knew I had found the right combination. This is the pack I still use when I dust the plane off for an Aerobatic fly-in.

I'm not sure whare some of the ideas they get come from. Maybe they are feedback from users, but I just can't picture being happy with the B ratio, or the D ratio. The plane is too heavy for the little 8" prop, and the control surfaces and stall speed too high for the 11" prop... IMO
Gene Bond is offline Find More Posts by Gene Bond
Reply With Quote
Old Mar 27, 2005, 09:13 AM
Jinx13
Jinx13's Avatar
Manila Philippines
Joined Jan 2005
162 Posts
My Formosa came with a EPS 350 B drive and 9x4.7,8x6 prop.. performance was not that good even with 8 kan 650 cells..

Changed it with a C drive and 9x7 gws prop,now it flies really well.. I use throttle management to maximize my flight time with the kan 650 cells,i get about 6 to 8 minutes in one charge and still have enough power for the landing..

Im still flying it stock and I've tried alot of gear and prop combinations but the C gear and 9x7 prop is the best for me..

Hope this helps

Jinx
Jinx13 is offline Find More Posts by Jinx13
Reply With Quote
Old Mar 27, 2005, 09:37 AM
Registered User
Santiago, Chile
Joined Mar 2003
168 Posts
hola acrored, no lo he probado en 9V 3 celdas, pero deberia funcionar. Saludos

trans: Hi acrored, No i havenīt tested the mod for 9V, 3 cells but IT should work.
Bye
chileno is offline Find More Posts by chileno
Reply With Quote
Old Mar 28, 2005, 11:40 AM
Registered User
Joined Jul 2004
510 Posts
HOLY WORD, Batman! Are we going multi lingo?
jimkirley is offline Find More Posts by jimkirley
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
A minor Formosa PROBLEM BUT I STILL NEED HELP Zachary Parkflyers 22 Aug 29, 2004 08:33 PM
Formosa Time Almost!!! JohnC Parkflyers 0 Mar 14, 2004 04:27 PM
Weird Formosa Problem-Need Advice! mrebman Parkflyers 4 Dec 28, 2003 11:34 PM