microdon2

My Feedback: (47)

Bill -

Thanks for the detailed explanation - that really cleared it up. I'm probably going to use your design for my 100" 260. Though I'm not sure if my charger does LiFe...

btw - If I get a Rev 90 under the Christmas tree then I'll KNOW Santa is real!

Mike

Spridal

My Feedback: (17)

Guys,
I just placed my second Revolver up for sale in the classifieds if interested. Perfect condition never crashed or abused with about five flights on the airframe.

wjcalhoun

Guys:
Have now completed the punch list items and am ready to maiden in the next few days. Tedious but important things like checking and setting throws, establishing fore:aft and lateral balance, double checking connections, blue loctite, etc.


I do have a few disappointments

1. The linkages of servos to elevators really is not precise. I have used 1 1/4" servo arms with AW control horns; with the geometry of the linkage different side to side, I had worried that the throws of the elevator halves would not be equal. Guess what? they are not. I am getting about 10% more throw on the L half than the right. I will see how it flies, but i'm almost certain that there will be some roll coupling with the elevator. I may have to build some structure in her aft and mount the elevator servos properly.

2. She was an ounce out of balance laterally; had to add an ounce of weight to the L wingtip. That is not related to distribution of weight in the fuse, but must relate to balsa density, or glue or something else. It is not that big a deal to fix, as the wingtip has ample solid balsa. See pics.

On the positive side, i am really impressed with the DLE55RA. It drew fuel and fired choked with 3 flips, and started and ran with three more. The fuel tank holds, I am estimating, 40oz, so one has the possibility of long run times.

After 15-20 min of idle -> midrange -> idle and a small mount of LS and HS needle adjustment, the engine ran WOT at 6500rpm. By the end of the tank (about an hour run time altogether), she turned 6750-6800 with a Xoar 22x10 beech prop. With that setup, i measured 27#8oz of thrust, so i have a T/W now of almost 1.5:1, which may get better with time. The engine runs smoothly, and even brand new would idle reliably at 1700rpm. Broken in, it will probably idle down to 1550 or 1600 like the DLE55 will.

My well-broken in DLE55 engines only turn 6800-6830 on the ground with the same prop, so I think the 55RA may well be good for the advertised 100 extra rpm.

We are all interested in flight reports from anyone else who has gotten their R90 into the air.

IMAC781

My Feedback: (2)

Please do not fly your plane with unequal elevator throws. This is easily resolved on one channel using Futaba or JR devices.

http://www3.towerhobbies.com/cgi-bin...?&I=LXCTS1&P=0

http://www.horizonhobby.com/products...system-JRPA900

Jomar, Smart-Fly and others also make them.

I don't think you need 1 1/4" arms but they are OK.

-cmh

wjcalhoun

Another option, that i will probably try first, is to program the servos differently; they are HS-7954SH fully programmable with the HPP-21 programmer, which i have.
Geometry always wins; i think the right thing to do ultimately will be to move the servos forward a bit so they can be properly mounted.

IMAC781

My Feedback: (2)

I am glad to hear your solution is at hand. Please do not fly your plane with unequal elevator throws.

wjcalhoun

IMAC
Thanks for your suggestions.
Do you have an R90? If so, do you have any thoughts on setup?
Thanks
WJC

IMAC781

My Feedback: (2)

My shop has no room at present but if it did there would be a R90. The setup is as straitforward as it gets with this size plane. First thing I would do is call [link=http://www.tntlandinggear.com/]TNT[/link] about one piece aluminum LG availability and wait for it. First classs stuff. Do the mods on LG plate, epoxy and tri stock, most guys know the drill; if you don't we will help you. If this is your first gasser please have an experienced pilot that you have seen fly his plane like you want yours to fly check it out. There is lots of useful info in this thread especially about fuel tank and pushrods. Always ask us if you're not sure. We all had help and are willing to pay back.

-cmh

wjcalhoun

Thanks IMAC
Sixth gasser, so i am pretty familiar with the general setup issues.
I have never had a plane DESIGNED with assymmetrical elevator servo placement - hence the question.

microdon2

My Feedback: (47)

IMAC - I'm with you in thinking my first step is to upgrade the LG with a single piece. Do you work for TNT? What gear would you recommend for the Rev 90? (or which existing one is close - trying to get an idea of cost). Also, what I've seen of aluminum gear wasn't great - they get bent out of shape. (maybe the gear I was using was on the cheap side). Does TNT aluminum keep it's shape, even after some hard landings?

WJC - thanks for pointing out this asymmetrical servo arc situation. Agree with you - why design it that way?? And when you asked the Rep specifically said it was the same. Would this be that hard for them to check in the design or testing phase?

btw - anyone with a Rev 90 considering skis?? Curious as to the make \ model \ size. I have skis from Maiden Model Products ( http://www.maidenusammp.com/products.htm) Pretty good, though I did have to enforce them after a while. But I think their largest ski goes up to an 18 lb plane, just shy of the 20 lbs for the Rev 90.

IMAC781

My Feedback: (2)

Odd setup, didn't we do this before servo reversing was common? Nothing that can't be overcome with any modern radio. Basically I can see nothing wrong with the geometry. I would do it the easy way and use the holes where mfg put 'em.

-cmh

IMAC781

My Feedback: (2)

No, just a loyal customer of TNT. All T6 6061 if TNT bends it's the least of your problems.

-cmh

Slow and Steady

TNT landing gear are nice but the gear I purchased were stout and somewhat heavy; bending would not be the issue. You may want to inquire on the weight before ordering. Graph Tech makes nice gear and may save some weight. They also provide dimensions for popular gear on their site and according to the site they will modify.

While I do not have this plane, I am surprised to hear that the elevator servos do not have the same geometry. I looked at the manual, and even though one arm swings above the servo, while one swings below, this should not effect geometry, if both control rods are equally distant from the stab and can be at 90 degrees to the servo arm at neutral position. A match box or synchronizer can provide equal end points and center but doesn't adjust servo speed or match throws except at center and end point. My Futaba 12 FG will adjust for speed so that the servos match along there entire length as will some of the Hitec programer. But I will be interested to see if that can make up for bad geometry along the entire length of the throw.

Another way to add weight to the wing tip is with 1/4 inch pieces of number 2 finishing nails that can be dipped in epoxy and dropped into a hole at the wing tip. I usually drill a hole with a forstner bit on the bottom side, lined up with the CG line. After dropping the nails in the hole, I just cover the hole with a small piece of mono coat.

Luchnia

My Feedback: (21)

The Hangar 9 Funtana X100 is built the same way. One servo faces up and the other faces down and as long as the rods and every thing is exact it works perfectly. The key is make sure it is all setup exact through the entire movement. I have to admit it looks cheesy too.

I don't know why they could not have designed it better. I don't like the setup nor would I do one that way during a build, but I can say it does work perfectly as I have flown the X100 many times with no issues whatsoever.

wjcalhoun

S&S and Luchnia
Agree on your assessment of the geometry - the 'ifs' are where the rubber meets the road.

On my build, in order to get the elevator throws i want, i needed to use 1 1/4" arms. That puts one control rod closer to the stab than the other. The arms at neutral are at 90*, but there is a small difference in geometry which appears to be the root cause of my throw asymmetry.

My guess is that if i went back to 1" arms, the issue might disappear, and i may do that. If i want more throw, I can move in one position on the AW control horns.

I'm going to try matching endpoints and centering with my hitec servo programmer first; if that does not work, I'll go back to 1" arms.

Like Luchnia, I wish the servo structure had been placed a bit farther forward, so the mounting could be symmetrical, but for me to do so is not really a big deal. If i have to go that way, I will. It could also have been more favorable with respect to fore:aft CG to move relatively heavy servos forward 4 or 5 inches.

I'll see how she flies when i get the elevator throw issue squared away. If i need to reduce weight, i think one piece carbon fiber main LG would be a pretty good first step. The stock gear are heavy.

taildragger56

Great information here! I was looking for the dimensions of the main gear and could not find them. Would some one be so kind as to post the dimensions? I have not received my revolver yet, and it won't be here for a couple weeks.Just wanted to get a jump start on ordering some new gear.


Thanks again for all the info!!

bob

edwal07

When using the Aeroworks linkage from the Ultimate, I turned the servos around so the arm was forward to match the length of the control rods. I measured my elev's and they are spot on including max throw. Turning the servos gives you a little more length from the control horn. It looks wierd and that is why I checked it ( in the beginning of this thread are my measurements). Check the earlier threads as I have pictures of the elevator setup. I have about 15 flights on my R90 and it is still performing excellent. The only problem I had was a tie wrap broke that secured my ignition battery. Other than that, perfect. I would still suggest to move your throttle up front in the engine box for a shorter control rod and makes it look cleaner in the body area.
I just read the review in FlyRC magizine that they did on the R90. I thought it lacked for information, especially since we as a group have found more than one problem that needs to be addressed. Seems as he had no problems with the setup out of the box. Just once I wish they would send me one for an honest and straight forward review!
Ed

wjcalhoun

Ed:
That is an interesting idea to turn the servos around; it would also reduce geometrical problems by shifting the pivot further away from the control horn.
Are you using 1 1/4" servo arms, or 1"?

Having thought about this matter more, I am inclined to go to 1" arms, which will obviate the geometry issues, rather than program the servos to compensate for a geometry issue; if i need more throw, i can move in on the AW horns.

Bill

Slow and Steady

From what I have heard, many reviewers are flyers and not journalists and most reviews appear to be scripted; I wonder if they are highly edited. It is rare to hear anything that is negative. It also seams that the only reviews are of advertisers products. I cancelled all of my subscriptions for these reasons, but have since renewed after experiencing withdrawal symptoms. I now mostly just brows the mags to see what new products are coming out. RC Reports used to do real reviews, but they went out of business a month after I subscribed.

Slow and Steady

WJ, can't you increase the throws on the Hitec 7954 by programming a longer arch on the servo i.e. increase from 120 degrees to 160? By the way, I have these on my 50cc Extra and they work great, except some chattered when I put a deflection meter on them. Hitec said they would still function fine and they have. Like the ultra torque, high voltage and price.

Luchnia

My Feedback: (21)

There always seems to be an issue with Revolver landing gear. Is the gear swept back? It doesn't look like it on the picture and if it isn't, I would think that several different gear would work as long as the width is correct. I have one set that was on a 40cc plane that are extremely durable and not really that heavy, yet they are aluminum. I do prefer the carbon fiber gear and I have a set on my GW 330L that I really like. They are super light and amazingly strong for the size.

edwal07

Hey Bill,
Yes I have the 1 1/4" arms but you can see I moved them in so yes they are at the 1" point or very close, I haven't measured them. I just looked at them when I installed them and tried to make the angles as close as possible. Must have done it right as it lines us and works just fine. Everyone at the club has loved the plane. One of my friends (my test pilot) absolutely loves it. He said it was one of the smoothest planes he's flown and can make it do perfect 4 point rolls. I am extremely happy with mine as I hope you will be. The DLA-56 is just getting better and better, acts like a DA-50 on the starts. Choke, flip, flip, pop. Choke off flip, flip, we're ready to fly.
I did change out my fuel tank as I stated earlier in another post to a 32oz Sullivan and a 10 minute flight uses about 1/4 of a tank or less. Now that's my flying style so everyone else will be different. Anyway try turning the servo's around and move it down to the 3rd hole and me thinks it will solve your problem.
Thanks

wjcalhoun

Luchnia
The gear have a very slight sweep, but not nearly as much as the R70. I'll take a photo tonight and post, and will measure the dimensions for taildragger.

S&S - you can reprogram the servos for a longer sweep; one loses resolution, but one also loses resolution (at the control surface) by using the inner holes on the horn.
That is another good suggestions. Thanks

Ed - thanks for your suggestions.

taildragger56

Thanks Guys, look forward to the pics and measurements!!

wjcalhoun

Taildragger:

Measurements:

Gear spread: 23 1/2"
Gear height (axle->mount): 8:
Depth of main gear (fore-aft): 1 3/4"

Very slight sweep back, which you can see in the pics; my guess is a non-swept gear would work fine

Bill