1/8 FE Questions

[Bill Schaare]

In the process of getting started on a MLB 1/8 hydro build. Strongly considering going FE mainly for cost and maintenance reasons. Have built/flown electric rc planes in the past, moved to gas; but still have most of my batteries and chargers. Mostly 4s, 60-70C rated. Don't plan on racing right away but would like to have everything set up to do so when time comes. Have some questions though:
1) Are there any other sources for 4092 860kv motors other than Offshore Electrics or Rattlesnake RC? RRC is out of stock. Not finding much on the net.
2) Is 70C rating a good minimum for batteries raced with? C rating questions I find here are over a decade old. Assume batts have gotten better. What is minimum mah rating to get through a typical race without taxing batteries? Realize greater mah rating would be better but means longer charging time. Means more weight, but are guys going extra big and getting 2 races out of 1 charge?
3) Any advice as far as good battery suppliers/ manufacturers to deal with or those to shy away from?
4) What kind of set-up are guys using to recharge batteries at racing sites?
Appreciate any and all help I can get. Thank you.-Bill

 

[Hydro Junkie]

Here are some cut and pastes from the R/C Unlimiteds FE rule book that might help you out a bit:
2. Electronic Speed Controls (ESC)
a. Any ESC may be used as long as it is rated to a minimum 130 Amps and rated to handle a minimum of 8s battery configuration.
b. Anti-spark resistors are advised on all speed controllers.

3. Batteries
a. A maximum capacity of 8S Lithium Polymer (LiPo) batteries are approved. Only LiPo batteries with a cell rating of 4.20 or less volts per cell are approved. Maximum charged voltage is 33.84 volts.
b. LiHV batteries with per cell capacities to 4.35 volts or higher are not approved

I can't help any further on batteries themselves but, as for charging, it's pretty much common for those racing to have a Honda 2000 series(or an equivalent) generator powering multiple chargers, usually four or more. The reason for multiple chargers is the average battery pack is only good for one heat. They run a heat and then swap out packs, putting the ones used on the chargers so they will be ready later in the day since we normally run four heats. This is especially important if the boat qualifies for a consolation or final heat. Obviously, the chargers have to be compatible with the type of battery packs being used and be capable of quick charging the packs so they will be fully charged for additional runs

 

[Samuel Hagan JR]

If it was me and I had plans on maybe racing it in the future I would atleast at minimum set it up for 8s and look at the rules for what organization your running. Amazon sometimes has the sss 4092. But OSe and rattlesnake have great customer service. You can’t get no better than those 2.

 

[Bill Schaare]

Planning on setting up for 8S, with 2 4s in series. How do you go about setting up antispark resistors on ESC's? Have never heard of this.

 

[Mike Hughes]

https://www.offshoreelectrics.com/proddetail.php?prod=ose-qs8-antiThey have the connectors with anti spark. Video shows a 60A load with no sparking. Check it out. Simple and you need a connector as well. So two birds on this one.
Mike

 

[Bill Schaare]

Hey guys. Was looking at link Mike Hughes sent (THX) above and noticed ESC accessories available on the OSE website. See they sell Capacitor Bank Packs. What are the purpose of these packs and do most guys who race utilize them? Before I went to gas engines in my large scale airplanes I used electric motors for power and never saw these before. Maybe due to lower rpm involved. Should I or would it be beneficial to be running one of these in my 4092 850KV, 8S set-up? If used how are these waterproofed? Appreciate the help. THX-Bill

 

[Don Ferrette]

Hey guys. Was looking at link Mike Hughes sent (THX) above and noticed ESC accessories available on the OSE website. See they sell Capacitor Bank Packs. What are the purpose of these packs and do most guys who race utilize them? Before I went to gas engines in my large scale airplanes I used electric motors for power and never saw these before. Maybe due to lower rpm involved. Should I or would it be beneficial to be running one of these in my 4092 850KV, 8S set-up? If used how are these waterproofed? Appreciate the help. THX-Bill

I just went back and found an old thread on ripple current and pinned it to the top. Lot of good reading there explaining the whole process of the extra cap banks-
https://www.intlwaters.com/threads/ripple-voltage.57952/