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Old Aug 14, 2010, 05:49 AM
Why the dirt on the wings?
moparmyway's Avatar
New York
Joined Jan 2009
5,000 Posts
Quote:
Originally Posted by rimripper View Post
I am wondering about running some batts in series for my bird,if the c rateing is different will it be a big issue?1 is a 40c and the other is a 20c.
Thanks,Greg.
It might be a HUGE issue.
For example, if you set your LVCO to a value of (just an example for the sake of the discussion) 3.7 volts per cell, and you run your 2 different batts in series, then you probably wont have any problem.

If you set your LVCO to a value of 3.0 volts per cell, then you will probably definately have some problems.

Here is why;
As your larger 3 cell battery (mAh/"C" rating) has its stored energy used up, it will hold a higher voltage per cell than your smaller (mAh/"C" rating) 3 cell battery. When the smaller battery has its volts per cell dwindle down to near the 3.0 volts per cell value (9 volts total), the larger battery would be closer to (say for example) 3.4 volts per cell (10.2 volts total). This difference can NOT be recognized by any ESC, and since the ESC reads total volts, it will think you can still fly because the LVCO for 6 cells would be 18 volts and you will still be supplying 19.2 volts to the ESC. The harder working battery (smaller one) will produce much more heat (could be a disaster right there), and will really run into HUGE problems as it crosses under the minimum volts per cell (usually 3 volts per cell). This destroys any battery and usually makes for a spectacular in air disaster and sometimes fire....................which MUST come back down to the ground.
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Old Aug 14, 2010, 09:35 AM
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rimripper's Avatar
Alberta,Canada
Joined Nov 2009
2,484 Posts
Thanks Mopar,I don't think I will try this,I think I will be purchasing a new batt.I had a little bit of arc between two zippy 2s and one is no longer with us....but atleast it didnt explode in my face.Now I have a 2s that I really do not have any need for unless I run it in series with a 3s to make a 5s the only problem is my 3s is alot newer and is not the same brand batt,would this be an issue?They are 40 c rateing though.So now I will be running my stryker on 3s for the time being.Thanks for the answers.
Greg.
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Old Aug 14, 2010, 09:44 AM
Why the dirt on the wings?
moparmyway's Avatar
New York
Joined Jan 2009
5,000 Posts
Quote:
Originally Posted by rimripper View Post
Thanks Mopar,I don't think I will try this,I think I will be purchasing a new batt.I had a little bit of arc between two zippy 2s and one is no longer with us....but atleast it didnt explode in my face.Now I have a 2s that I really do not have any need for unless I run it in series with a 3s to make a 5s the only problem is my 3s is alot newer and is not the same brand batt,would this be an issue?They are 40 c rateing though.So now I will be running my stryker on 3s for the time being.Thanks for the answers.
Greg.
Please remember the example in post 9811 above. If your older battery is not as strong as your newer one, the same difference in volts per cell between batteries COULD happen.

Battery manufacturers reccomend that series batteries be so similar, that they even suggest you dedicate the series batteries just for that purpose, without mixing and matching. They suggest that you basically marry the batts together and dont use them in any other application, except in series with each other.

I have been guilty of not following this, and have gotten away with it, but I monitor my batteries like a miser, and if I dont see equal voltage drops, equal discharges, and equal power deliveries and charges, then I dont run them in series anymore.

LiPo's can be extremely dangerous, so please err on the side of caution and keep series batteries married and monitored.
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Old Aug 14, 2010, 09:54 AM
Fly it like you stole it!
chevypower1930's Avatar
USA, NC, Raleigh
Joined Jun 2009
832 Posts
Well I finally powered up the Stryker this morning and all I can say is WOW.... this thing has power with just the upgraded motor. had to solder on my deans plug so hadn't been able to run her up yet and I think I'll be pretty happy with the power for now....

I can't imagine what yalls 150+ mph strykers are like
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Old Aug 14, 2010, 10:08 AM
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rimripper's Avatar
Alberta,Canada
Joined Nov 2009
2,484 Posts
Quote:
Originally Posted by moparmyway View Post
Please remember the example in post 9811 above. If your older battery is not as strong as your newer one, the same difference in volts per cell between batteries COULD happen.

Battery manufacturers reccomend that series batteries be so similar, that they even suggest you dedicate the series batteries just for that purpose, without mixing and matching. They suggest that you basically marry the batts together and dont use them in any other application, except in series with each other.

I have been guilty of not following this, and have gotten away with it, but I monitor my batteries like a miser, and if I dont see equal voltage drops, equal discharges, and equal power deliveries and charges, then I dont run them in series anymore.

LiPo's can be extremely dangerous, so please err on the side of caution and keep series batteries married and monitored.
O.k thanks again Mopar,I will be getting a single batt.4s for my bird then I can stay away from the series connection.I finished setting every thing up last night so here is a pic of the competion.I was also able to install a heat sink on it.Also what are some good starting rates for this bird on high & low.
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Old Aug 14, 2010, 12:02 PM
Home of A-10 - Farmingdale NY
boiko's Avatar
United States, NH, Londonderry
Joined Dec 2006
936 Posts
Thanks moparmyway for the reply back.....

Has anyone tried the Nano-Tech (Hobbycity) batteries yet in their Stryker..and if so what has been your experience?

-mike-
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Old Aug 14, 2010, 01:58 PM
Not again!!!!!!!
Switch2403's Avatar
Dallas, Texas
Joined Apr 2010
103 Posts
Quote:
Originally Posted by Arcteryxxx View Post
Started building my first heavy-weight Stryker today. Here's a pic of the CF installation.
As you see the tip-to-tail rod is still missing. That's because I'm going to build a bungee hook on it.
Can anybody give me some hints about the best way to make such a hook?
Your CF installation looks very good and clean Arctery. I am also starting another build and will be following mopars thread (Thanks for the link). I was thinking about using gorilla glue instead of hot glue to save on wieght this time. Does anybody have any negative thoughts about this?
Also, I was going to cover my wooden elevons and 3/8 x 3/8 wooden trailing egdes with CA. Can somebody tell me what kind of CA to use and how much it will take?

What size CF rod is everybody using?
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Old Aug 14, 2010, 02:18 PM
Victim of C.D.O.
murdnunoc's Avatar
United States, TX, Lubbock
Joined Oct 2007
4,081 Posts
Switch,
Gorilla glue works GREAT for installing carbon tubes. One thing you have to be absolutely careful on, though: Make sure you clamp the tube into its slot, as the Gorilla glue will expand and try to push the tube up and out of the slot. The best way I've found to clamp it is to, in about 4 or 5 places along the spar, leave about an inch without Gorilla glue on it and tack that portion down into the slot using low temp hot glue. This way, when the Gorilla glue expands, it will not be able to push the spar out.

Gorilla glue attains its great bonding strength by the expanding action. It's ideal for very porous materials like foam. If you contain the glue to resist its expansion, it forces itself deeper into the foam's pores. So I like to lay a strip of tape along the spar to keep the glue squished in. It'll leave a little hump of glue that you can shave off with a straight razor blade (I use a block plane blade).

Gorilla glue does take longer than hot glue, but I like the finished product it produces. Both glues are well-suited to gluing spars in, though.

I don't like CA at all for gluing foam. It dries very hard in comparison to the foam around it, and this can lead to cracking right next to the joint when it tries to flex, as in a rough landing/crash.
There is a "flexible" CA put out by Bob Smith Industries (it's the stuff that usually gets rebranded with your hobby shop's brand name). They have a thin variety in a light blue bottle, and a thick variety in a pink bottle. The thick stuff would be best for any foam gluing you decide to do with CA. But it's still not as well-suited to foam as low temp hot glue or Gorilla Glue.
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Old Aug 14, 2010, 02:18 PM
Eagleye
EAGLEYE-1's Avatar
Virginia Beach, Virginia
Joined Oct 2008
587 Posts
That Mile Out Stryker

Hey jriley...great video. Well done. Thought I was the only stryker guy out there with enough nerve to straf the surf. youtube: search ahailston
You can't beat a stryker! See ya in the skies (well, maybe!)
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Old Aug 14, 2010, 04:20 PM
Not again!!!!!!!
Switch2403's Avatar
Dallas, Texas
Joined Apr 2010
103 Posts
Quote:
Originally Posted by murdnunoc View Post
Switch,

I don't like CA at all for gluing foam. It dries very hard in comparison to the foam around it, and this can lead to cracking right next to the joint when it tries to flex, as in a rough landing/crash.
There is a "flexible" CA put out by Bob Smith Industries (it's the stuff that usually gets rebranded with your hobby shop's brand name). They have a thin variety in a light blue bottle, and a thick variety in a pink bottle. The thick stuff would be best for any foam gluing you decide to do with CA. But it's still not as well-suited to foam as low temp hot glue or Gorilla Glue.

I might not have been very clear about the CA I was talking about. I have read some post where guys will actually paint CA onto there balsa wood parts so it can absorb into the wood making it stiffer. I have never used or seen CA that comes in a can that can be painted on and absorbs into the wood before it dries. I think some people do this to prevent glassing of there elevons.
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Old Aug 14, 2010, 05:34 PM
Registered User
Blythewood, SC
Joined Dec 2003
219 Posts
Hello guys, I don't mean to burst in but, could someone tell me if this is a good motor for the Stryker? I'm currently using a Warp 4 BL 15-4 on 3 cells with a 6x5.5 prop.
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Old Aug 14, 2010, 06:16 PM
Victim of C.D.O.
murdnunoc's Avatar
United States, TX, Lubbock
Joined Oct 2007
4,081 Posts
Quote:
Originally Posted by Switch2403 View Post
I might not have been very clear about the CA I was talking about. I have read some post where guys will actually paint CA onto there balsa wood parts so it can absorb into the wood making it stiffer. I have never used or seen CA that comes in a can that can be painted on and absorbs into the wood before it dries. I think some people do this to prevent glassing of there elevons.
Nope, you were clear. I was just reading too fast

I've coated parts in CA. Works well. Use as thin as you can, like the "instant" "1-3 second" or "thin" variety. The blue bottle stuff.

The way I spread it is to wrap a piece of packing tape on two or three fingers, sticky side against fingers, and spread it "by hand". A brush will become too stiff to use almost instantly, and a spreader doesn't give you enough control.

Just drip the CA liberally onto the part and smear it all around with your taped fingers. They won't stick as long as you keep them moving.

Mine may not be the classiest method, but it works. There may be better ways, too...

I like the idea of CA hardening for the elevons.

And please, for the love of everything pure, do it outside! With a fan!
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Old Aug 14, 2010, 07:14 PM
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Peter M's Avatar
Newcastle, New South Wales, Australia
Joined Sep 2007
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Quote:
Originally Posted by murdnunoc View Post
....I like the idea of CA hardening for the elevons.

And please, for the love of everything pure, do it outside! With a fan!
I've found CA harden balsa elevons to be stiffer than the commonly used epoxy coating only method.

I've also been using CA to attach 1 1/4oz fibreglass cloth to the the elevons too and this is now my preferred method. However I haven't prefected the process yet as I only can seem to get one side perfect and the other becomes a bit bubbly if I am unable to keep the cloth in tension before I apply the CA. This method is quick and a sanding block cleans up your handiwork quickly.

I like Murd's suggestion to use tape finger "protection". I've been using latex rubber gloves but you do go through a few. The secret is to keep your finger moving otherwise it will become part of the elevon!

+1 for plenty of ventilation as CA fumes up the nose is one of the most unpleasant sensations I can think of!
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Old Aug 14, 2010, 07:30 PM
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rimripper's Avatar
Alberta,Canada
Joined Nov 2009
2,484 Posts
Well I tried to put packing tape from the foam wing across the elevron and it seems that it reduces the servo throw is there a secret method that I am not aware of?Also picked up a 4s today so Im not running series batts,less room for error.Any help with the tape would be great as I would like to make the best I can.Is there much difference from the 6x4 props to the 6x4e?
Thanks guys,Greg.
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Old Aug 14, 2010, 07:33 PM
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beginner4life's Avatar
United States, MD, Ellicott City
Joined Mar 2008
1,198 Posts
I think all that is happening is the elevon is stiffer with the tape on so the servo cant pull it as far
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