Luchnia

My Feedback: (21)

I had some kludge on my shoe once...wait, was that kludge? Maybe it was something else. We got jokes (NOT) [X(] [8D]

wjcalhoun

Don:
On the CG question, I think it is fair to say that the book location is very conservative - that is to say, FORWARD of safe. I'm sure that they recommend that CG because it is safe, if a builder doesnt measure properly and is off by 1/2" aft, it will still fly, the plane is smooth there, etc.

Having said that, i have moved my CG back more than 1/2" aft of book, and i like its flying characteristics much better. Snaps better, flat spins better, and slows down for landing better. Nose heavy planes land fast.

If I were you, I would fly it with the CG at recommended, or not more than 1/4" aft of that for a few flights, and then move to your comfort zone. Keep in mind with the forward CG that good elevator control on your flare is important; touching down with too much forward airspeed (actually groundspeed) may cause the main LG to depart the airframe.

ahicks

My Feedback: (2)

-touching down with too much forward airspeed (actually groundspeed) may cause the main LG to depart the airframe. -

Almost a certainty.....

It's hard to suggest where to place the CG much beyond what the book sugggests. If I said how far back I was, and you weren't prepared for how slow that plane REALLY can fly without falling out of the air, you're likley going to be repairing more than the LG? You would need to be prepared to maintain your airspeed manually, which might involve dropping the nose or increasing the throttle if/when the plane slows too much?
-Al

VictoryRoll

My Feedback: (2)

@wjc & @hicks   Bill & Al,

capt1597

VR- because it is tight to work on th inside i decided to remove the covering on the bottom half of the fus. and do my reenforcing on the exterior. i used this cloth http://www3.towerhobbies.com/cgi-bin...&I=LXL491&P=ML and built up five layers. the area involved is about seven in long and goes up each side and the front about one in. after sanding and recovering you cannot tell that anything was done. i then used an epoxy brush and painted the inside with epoxy without fillers. very strong, clean look, light, three years flying off grass strips, no damage. very easy mod. cheap! just my two cents happy flying, capt

VictoryRoll

My Feedback: (2)

Nice Capt ! I already stripped back the covering in preparation for doing some exterior fiberglassing. I am using same type of cloth from TH but 2oz, not the (5) 3/4oz you have. I am thinking one layer is all that is needed, maybe two, but w/ 2oz., that seems like overkill... you agree?

So, let me get this straight, you went up the curved sides about 1" and back from the edge of the firewall about 7 inches? and did you go up the exterior of the firewall until it met the engine mounting box? Did you do this with one piece (I understand 5 layers, but 1 piece)?

Any details would be great and/or pics.

Thank you so much for your help and knowledge.

Don

capt1597

yes one piece per layer. that said the thinner cloth was very easy to mold around the bends. i don't know cloth weights well enough to know how well your's will bend. and yes i went up just shy of the mount in front

capt1597

you are probab;y right that one layer of 2oz will be enough.

wjcalhoun

Al - roger that comment It is why i did not specify exactly where mine is!

ahicks

My Feedback: (2)

You have in the past I believe, and mine's there as well.

Don, 1/4" is a great plan for testing!

PDF

Hello all,
What are you pilots using for replacement main landing wheels if you replace them? I'm just starting my build and picked up today some supplies to get started and one was a set of 3 1/4" Dubro low bounce wheels, they weighed in at 6 ounces and the stock wheels are 1.6 ounces. That's a considerable amount difference but I didn't like the stock wheels, are there any different brands that you pilots use that I could look into.
Thanks for you help,
Pat

ahicks

My Feedback: (2)

Stock here. Flying off grass without issue. Mine are covered by wheel pants, so weight is my biggest concern.

afjetmech

I'm using the Dubro low bounce and those plus the DLE20 up front have me mounting about 2 oz of weight on the tail, but you know what? This combo is still a rocket ship, will land slow with a slight headwind, and really doesn't seem to mind a few extra ounces here and there. Some people are anal about their weight (on their aircraft) but unless you're building it for 3D I wouldn't worry about a few extra ounces.

prr6100

I am in the middle of an engine change on my R70, going from a Magnum .91 to a DLE 20, I have subscribed to this thread for several years and have upgraded the landing gear and the hinges already. I know these issues have been discussed here, but it would help if I knew which post number to look for advice. I am concerned about strengthening the firewall and moving the battery to balance better. Would going to a single battery work? At this time I am using a NiMh 6v, 2500 mah, with the DLE 20 I feel I need an additional battery if I stay with this set up, I would consider LiFe, but would prefer not to use LiPo's. my radio is Futaba 2.4, servos are Futaba 3010's all around except on throttle, I am hoping to not have to move the servo's to the tail to balance it, may as well work on it now, this spring wether is awful, thanks for any help.

afjetmech

I'm using a 3200mah Life mounted in front of the servo tray on the vertical former. Also using the Syssa IBE http://www.syssaaircraft.net/cart/pc...5&idcategory=2. Love this setup and can fly at least 6, 15 minute flights. Truthfully, I've neverquite calculated how many Mah I'm using per flight but I'm sure someone here has posted an average using the DLE20 and digital servos.

ahicks

My Feedback: (2)

prr6100 -
I don't think there much of any downside regardind A123/LiFe. More and more converting to this system as more experience is gained.

I'm running a single 2300mah A123. 6 to 8 flghts with some notoriously power hungry servos, and still plenty left to fly on if desired. I'll fly 2 evenings in the summertime between charges?

prr6100

thanks, are you running the electronic ignition off this battery too, if so, did you install a electronic engine cutoff?

ahicks

My Feedback: (2)

I use an Rcexl opti switch with a single 1N4007 diode in the output leg. Some guys are running their ign. modules on the 6.6v straight from the battery, but I'm old school I guess. For the price of that diode (Radio Shack 1.00 tops) I solder it in and drop the voltage about .7v - which lets me sleep better. -Al

prr6100

thanks

VictoryRoll

My Feedback: (2)

Question:  Your preference???

PDF

Just curious has anyone had and issues with control horns coming out? I think I only came over one post that had a person say he is going to thru screw the control horn. Is the stock 2 screw good enough or do you add additional screws?
Thanks again,
Pat

wjcalhoun

Don:
I would go with the Sullivans. I have actually used nylon dubros, but they do wear and bend with the kind of flying i do.
The sullivans are light strong, and if well mounted are very secure.

Pat
For stressed surfaces, when possible i bolt through the surface with #2 bolts, and capture the end of the bolt with a nylon lock nut. Sometimes that is not possible, and then RTL #2 socket head servo screws are great.

VictoryRoll

My Feedback: (2)

Thanks Bill, much appreciated... and I agree... I have them on my Big Stik 40, which has gone thru many of fun flys and aggresive manueavers, but I also have the Dubros on on a couple of my other planes which don't get the rigorous workout, but none-the-less, get plenty of stress and strain.

I thought about this overnight and remembered that I will have to compensate for the (servo bay)-to-(aileron reinforcement) alignment issue, which has been discussed to death earlier in this thread, as you know. The Dubros will make that compensation easier.
The Sullivans would have to be angled to compensate for the mfr. defect.

I am going with the Sullivans on rudder & elevator and use the Dubros on the ailerons. When the new wing set comes in (early May ?)I will be switching to the Sullivans on ailerons then. Sound like a plan?

Thanks for helping me make up my mind.

Don

PDF

Hello all,
I just purchased 4/40 control rods for the 70 revolver and pushed them in the stock plastic guides and there is a lot of friction in the guides. If I put in the 2/56 rods it's definatly better, I was going to make my own rods out of 1/8" mig wire but can see that'll be even more friction/resistance. Have any of you had this issue with upgrading the rods to 4/40? In fact is this a justifiable mod?
Thanks for all your help,
Pat

microdon2

My Feedback: (47)

PDF - Once I cut out the last inch of grey pushrod guide tube, to free up the rod. At least I take a blade and expand the open end.