Weight Saving for Electric 2m  
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Weight Saving for Electric 2m - 7/7/2006 12:44:14 AM   
papadontscreech


 

Posts: 37
Joined: 3/26/2005
From: , UNITED KINGDOM
Status: offline 		Hi

Just finished ZN Oxalys (hacker-TP5300s) and am a bit on the heavy side(about 100g overweight without spinner/spats)
Can anyone tell me any weight saving tricks to help me out, already put airframe on diet so gonna concentrate on the electronic/metal bits. Any suggestions?( 9650s tail-9451s ail/rudder )
Also would anybody know where I can get aluminium or titanium m4 bolts( wing attachment ) as these weigh 20g alone.


Thanks
       Post #: 1

RE: Weight Saving for Electric 2m - 7/7/2006 4:28:17 AM   
PatternPilot



Posts: 525
Joined: 11/17/2002
From: Knoxville, TN, USA
Status: online 		Here is a web site for hardware, http://www.fastener-express.com/index.asp
also think about a 2 cell lipo for RX and servos, leave the spats off and look at the some of the small servos .9 oz with 65-80 oz of power on 6 volts. Tail wheel and main gear you can save alot there if you get the right wheels..

Scott Anderson
Team Tanicpacks.com
Team Castle Creations

(in reply to papadontscreech)
       Post #: 2

RE: Weight Saving for Electric 2m - 7/7/2006 6:29:35 AM   
can773



Posts: 1652
Joined: 1/25/2002
From: Calgary, AB, CANADA
Status: offline 		Use these for wheels...

http://www.maxxprod.com/mpi/mpi-29_files/epw.jpg

http://www.maxxprod.com/mpi/mpi-29.html

Maxx products wheels, they dont last too long (200 flights) but a pair of them weighs nothing

Rx pack is another good place as mentioned....typical e setups use 40-60 mAh/flight so you can easily get away with a 2s 480 size pack.

Remove any excess power system wiring, get rid of as many connectors as possible. Easy way to do that is wire the packs as a single 10s unit....provided you have a charger that can deal with that. Saves a lot of wire weight and connector weight vs. running a series join connection at the esc.

ZN kits are already pretty light, I know its tough. Get a carbon stab tube from them if you have not already.

Cut out as many spokes of the light back plate spinners as possible...you really only need 3, they have 6 usually (tru-turn anyways).

Aluminum fasteners as you already know

Smaller Rx

Do a carbon copy of the canopy....I think guys were saving 40-60 grams over the clear canopy that normally comes with the kit. At that point you can likely cut out the canopy floor which will eliminate a bunch of weight.

Thats all I can think of for now.




_____________________________

Chad Northeast

(in reply to PatternPilot)
       Post #: 3

RE: Weight Saving for Electric 2m - 7/7/2006 6:55:18 AM   
KeithB



Posts: 533
Joined: 1/6/2002
From: Garland, TX, USA
Status: offline 		1. ES fiberglass spinner - WAY lighter than TT.

2. 2-cell LiPo battery for RX. I have a 900 mah, but that's even overkill. I only pull out about 40 mah for each 9 minute flight. This can be a BIG weight savings.

3. Don't use a regulator with a switch. Just plug it in directly each time.

4. Use the super light foam wheels.

5. Shorten wiring as much as possible between the ESC, motor and batteries.

6. I used aluminum bolts even to mount my landing gear (6-32) and it's PLENTY strong (www.fastener-express.com/index.asp)

7. For air dams use the lightest foam you can find. The depron is good and light and can even be lightened more by routing out lighting holes that go only half way through.

8. I don't know the Futaba servos, but the JR 3421SA for the tail is a really light servo that works great (less than 1 oz. each).

9. If you get really desperate you can use the standard (not heavy) gage to the aileron servos.

Best of luck,
Keith B

(in reply to papadontscreech)
       Post #: 4

RE: Weight Saving for Electric 2m - 7/7/2006 9:05:55 PM   
wk9000


 

Posts: 8
Joined: 3/14/2004
From: New York, NY, USA
Status: offline 		I'd do the above but note also Deans connectors are heavy as is any un-needed length of wire.

A y harness made of deans connectors is quite heavy. I use a pair of jeti 3.5 mm connectors in
parallel for each lead. Astro flight's (gold plated copper) connectors, lighter than Deans but nice as
they are- are heavy too.

Great flying..

(in reply to KeithB)
       Post #: 5

RE: Weight Saving for Electric 2m - 7/8/2006 7:04:37 AM   
patternjockey



Posts: 89
Joined: 11/23/2002
From: Brentwood Bay, BC, CANADA
Status: offline 		All good stuff...

1) As Chad said, remove 3 of the TT backplate spokes (yet to do this myself)

2) Replace the TT spinner bolt with a nylon one (10/32)

3) Lathe down as much of the TT prop nut as possible (don't go crazy... it holds the prop on!)

4) Lathe up an aluminum washer (it will gall up over repeated tightenings but use care and it should last)

Dave



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Dave
http://members.shaw.ca/patternwestnews

(in reply to wk9000)
       Post #: 6

RE: Weight Saving for Electric 2m - 7/8/2006 8:26:49 PM   
papadontscreech


 

Posts: 37
Joined: 3/26/2005
From: , UNITED KINGDOM
Status: offline 		Thanks for the tips, I have applied most of the above tips, thanks.

Two things, Chad what weight are those wheels, mine are currently 5g each.
Does anybody know where to get longer aluminium bolts,that site only has them to 20mm.

Thank You

(in reply to patternjockey)
       Post #: 7

RE: Weight Saving for Electric 2m - 7/9/2006 2:08:57 AM   
can773



Posts: 1652
Joined: 1/25/2002
From: Calgary, AB, CANADA
Status: offline 		papa, the MPI 2.5" wheels weigh 7g each.


_____________________________

Chad Northeast

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       Post #: 8

RE: Weight Saving for Electric 2m - 7/10/2006 7:23:17 PM   
j woodward



Posts: 78
Joined: 12/8/2002
From: Miramar, FL, USA
Status: offline 		GWS makes a 2.0" x 3/8" foam tire that has a medium sized white spoked hub - weigh even less that the MPI stuff. These were 0.21 oz for the pair - versus something like 2.5" Dubro foam tires which are 0.82 oz for the pair.

Never thought I'd be shopping in the park-flyer section of the LHS for 2M pattern equipment.

Jim W.

_____________________________

Team Futaba - YS Performance - Morgan Fuels
R/C Enterprises - Aerotech - Budd Eng.

(in reply to can773)
       Post #: 9

RE: Weight Saving for Electric 2m - 7/11/2006 3:37:38 AM   
J Lachowski


 

Posts: 395
Joined: 9/2/2003
From: Bridgewater, NJ, USA
Status: offline 		Hobby Lobby has some fairly light wheels too.


_____________________________

Joe Lachowski
NSRCA 330

(in reply to j woodward)
       Post #: 10

RE: Weight Saving for Electric 2m - 7/11/2006 3:45:03 AM   
can773



Posts: 1652
Joined: 1/25/2002
From: Calgary, AB, CANADA
Status: offline
quote:

ORIGINAL: can773

papa, the MPI 2.5" wheels weigh 7g each.


FYI...

I would only use these wheels if you "have" to.....I had no choice because of the narrow-ness of the newer ZN wheelpants...nothing else would fit. Problem is after 175ish flights they are nearly destroyed and need replacement.

Something with a lot more cross section and stiffer would last a lot longer.


_____________________________

Chad Northeast

(in reply to can773)
       Post #: 11

RE: Weight Saving for Electric 2m - 7/11/2006 10:22:26 PM   
papadontscreech


 

Posts: 37
Joined: 3/26/2005
From: , UNITED KINGDOM
Status: offline 		Thanks Chad, the wheels i am using are 5g each, and a lot wider, They were 9g but I lightenned them and have still retained their stiffness,forget where I got them but they are 2", as for the fastenners, anybody know where I can get 30-50mm aluminium/titanium bolts(wing bolts) ,above link only does them to maximum 25mm

Thanks

(in reply to can773)
       Post #: 12

RE: Weight Saving for Electric 2m - 7/12/2006 1:01:56 AM   
patternjockey



Posts: 89
Joined: 11/23/2002
From: Brentwood Bay, BC, CANADA
Status: offline 		Try this: http://www.microfasteners.com/

Spent 45 minutes with the drill press, file, dremel and polisher to produce this back plate. My crappy scale says I lost 5 grams... (it only measures in 5 gr increments



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< Message edited by patternjockey -- 7/12/2006 7:17:29 AM >


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Dave
http://members.shaw.ca/patternwestnews

(in reply to papadontscreech)
       Post #: 13

RE: Weight Saving for Electric 2m - 7/12/2006 1:20:57 AM   
papadontscreech


 

Posts: 37
Joined: 3/26/2005
From: , UNITED KINGDOM
Status: offline 		NIce job on spinner Dave, that link doesnt have m4 aluminium bolts either, pity I reckon I could save 15g on those alone

(in reply to patternjockey)
       Post #: 14

RE: Weight Saving for Electric 2m - 7/12/2006 7:17:01 AM   
patternjockey



Posts: 89
Joined: 11/23/2002
From: Brentwood Bay, BC, CANADA
Status: offline 		Oops sorry about that... should have looked closer. With the exception of the wing bolts, I have changed all mine to aluminum... here is another option I am exploring...

http://www.lynxmotion.com/Product.aspx?productID=143&CategoryID=80

These things weigh almost nothing... already have them in the stab and great for cowling attachments etc.. I would caution not to use them on landing gear unless you can land as smooth as Chad .


_____________________________

Dave
http://members.shaw.ca/patternwestnews

(in reply to papadontscreech)
       Post #: 15

RE: Weight Saving for Electric 2m - 7/1