Author Topic: RSM OTS Ringmaster (Read 6433 times)

Andrew Saunders · « **on:** February 05, 2014, 04:01:19 PM »

I am getting ready to build a RSM OTS Ringmaster. I am gonna run a reworked O.S. Max FP 25 on it. Is there anything i need to know aboout this kit? Any building tips? I do plan on building the wing in a jig. Any other help or advice will be greatly appreciated.

Rick Bollinger · « **Reply #1 on:** February 05, 2014, 04:16:07 PM »

Andrew
Looking forward to seeing it this summer maybe at the Nats.

Andrew Saunders · « **Reply #2 on:** February 05, 2014, 04:38:03 PM »

I may bring it. Dont know if ill fly it. Ill be flying my Carribean cruiser in the beginner NATS.

Scott Hartford · « **Reply #3 on:** February 05, 2014, 05:15:13 PM »

Reinforce the leading edge where it exits the sheeted bays. Many have broken there.

Andrew Saunders · « **Reply #4 on:** February 05, 2014, 05:21:15 PM »

What would you suggest reinforcing it with?

Mike Keville · « **Reply #5 on:** February 05, 2014, 06:09:17 PM »

Excellent kit. Well worth the cost. Built one of the prototype kits back in '05, powered with an OS .25FP. Worked very well 'til I let it get too low on the 4th corner of the Square Loop. - Ouch!

Randy Cuberly · « **Reply #6 on:** February 05, 2014, 06:14:30 PM »

Quote from: Andrew Saunders on February 05, 2014, 04:01:19 PM

I am getting ready to build a RSM OTS Ringmaster. I am gonna run a reworked O.S. Max FP 25 on it. Is there anything i need to know aboout this kit? Any building tips? I do plan on building the wing in a jig. Any other help or advice will be greatly appreciated.

Hi Andrew,
The Ringmaster makes a great OT Stunt airplane with either the OS FP25 of OS LA25.
I am a little curious to know what kind of "rework" one would think is needed for an FP25...they run very well with the correct muffler pretty much "out of the Box".

Randy Cuberly

Steve Riebe · « **Reply #7 on:** February 05, 2014, 06:30:28 PM »

I would highly recommend you slow down the controls as much as possible. Use the bellcrank hole closest to the pin, and you might still need a taller control horn. They stall very easily with the large elevator surface. I'm up to 5 Ringmasters now, powered from a .15 through .35 Fox. The .25 FP makes as much power as the Fox, I think my best one has an Enya 19.

Mike Keville · « **Reply #8 on:** February 05, 2014, 06:39:07 PM »

Agreed = slow down the controls by using a longer control horn. Learned that tip from Bart K., who won OTS at the VSC more than once. Works very well.

John Cralley · « **Reply #9 on:** February 05, 2014, 08:20:16 PM »

All of the above are good suggestions.

As to the reenforcement of the leading edge, plywood, fiberglass, carbon fiber whatever you have will work. It is also a good idea to reenforce the spar too.

I suggest that you suspend the bellcrank between two plywood plates and for that matter, you might want to place the bellcrank in the inboard wing root so that the pushrod is on the inboard side of the fuselage ( then you can easily convert to electric power at some later date

).

ericrule · « **Reply #10 on:** February 05, 2014, 08:41:34 PM »

The RSM OTS Ringmaster already comes with a reinforced leading edge. The ribs notch into a Long Spar which runs at the back of the leading edge. Behind that spar there are vertical grain sheer webs. The effect of this is to produce a cross grain spar which is laminated and provide more than enough strength to resist any normal flight loads. In all of our flight testing over the many years that we have produced this model we have never broken a wing. The only report I have ever received from a customer who broke a wing stated very clearly that he (the customer) forgot to glue the sheer webs behind the notched spar. As far as the bell crank goes the kit comes with the necessary plywood bell crank mounts to install a suspended bell crank. In addition the rear spar also has a plywood doubler to provide extra strength for that structure.

When built properly as per the printed plan the structure is designed to withstand all normal flight loads.

Regards
Eric Rule

john e. holliday · « **Reply #11 on:** February 06, 2014, 08:58:47 AM »

I have one of Eric's kits and it looks great. Build it like he says and you should have no trouble. It is as close to the original S-1 kit as a person can get it.

ray copeland · « **Reply #12 on:** February 07, 2014, 04:26:57 PM »

With a 3 inch bellcrank with 3 holes for the pushrod, would you suggest the innermost hole or the middle hole? Thanks, Ray

Andrew Saunders · « **Reply #13 on:** February 07, 2014, 06:03:50 PM »

Whaen building the wing, would you build it flat on the plans or on a wing jig? I got the kti today and has allot more parts then the sterling kit i have built before. Im kinda dumb founded right now. Need all the advice i can get

Steve Riebe · « **Reply #14 on:** February 07, 2014, 07:49:22 PM »

Quote from: ray copeland on February 07, 2014, 04:26:57 PM

With a 3 inch bellcrank with 3 holes for the pushrod, would you suggest the innermost hole or the middle hole? Thanks, Ray

My own preference is the innermost hole. You can always "speed up" the controls with a short throw at the elevator horn, but it's really hard to slow down the controls once the plane is all done.

john e. holliday · « **Reply #15 on:** February 08, 2014, 07:49:15 AM »

Quote from: ray copeland on February 07, 2014, 04:26:57 PM

With a 3 inch bellcrank with 3 holes for the pushrod, would you suggest the innermost hole or the middle hole? Thanks, Ray

Yes. The inner most hole. Use a 4-40 ball link also. I still get too much movement on my version even at that. Also you might notice the elevator is larger than the stab.

Mike Griffin · « **Reply #16 on:** February 08, 2014, 10:30:56 PM »

I have lost count of how many of RSM Ringmasters I have built but if you will do what Eric Rule said, using the vertical sheer webbing, your wing will not fold. I have never had it happen

Mike

Larry Renger · « **Reply #17 on:** February 10, 2014, 05:58:02 AM »

I saw that wing fold. The pilot (you know who you are!

) had just put a .40 on the model. It had been OK with a milder .35, despite lack of shear webs. (not sheer, BTW)

Andrew Saunders · « **Reply #18 on:** February 16, 2014, 05:02:02 PM »

Heres what i have done so far

Brett Buck · « **Reply #19 on:** February 16, 2014, 06:09:35 PM »

Quote from: Larry Renger on February 10, 2014, 05:58:02 AM

I saw that wing fold. The pilot (you know who you are! ) had just put a .40 on the model. It had been OK with a milder .35, despite lack of shear webs. (not sheer, BTW)

The engines that really started the carnage are the Veco 19 and 20/25FP. With a Fox you just can't corner it hard enough to have a problem.

Brett

Andrew Saunders · « **Reply #20 on:** February 16, 2014, 06:23:46 PM »

Its getting a FP .25

afml · « **Reply #21 on:** February 16, 2014, 06:43:47 PM »

Look'n good Andrew!

Keep up the great work & keep those pictures com'n!

"Tight Lines!"

Wes

dennis lipsett · « **Reply #22 on:** February 16, 2014, 07:10:43 PM »

These kits build into a nice model. This one was built in 2 years ago while recuperating from neck and arm problems. I built it almost completely with my left hand as the right arm didn't work too well then. Power is an OS20 which I think is almost too much for the model. weight isn't too shabby at about 26 ounces and never painted . The only modification was shear webs on the trailing edge as the end of the ribs were a little short for my taste. It's an easy build

Steve Riebe · « **Reply #23 on:** February 17, 2014, 04:33:30 AM »

Looking great. Should fly really well with the FP25. Looking forward to finished photos.

Paul Smith · « **Reply #24 on:** February 17, 2014, 05:56:03 AM »

Quote from: ray copeland on February 07, 2014, 04:26:57 PM

With a 3 inch bellcrank with 3 holes for the pushrod, would you suggest the innermost hole or the middle hole? Thanks, Ray

I prefer using the outer hole at the bellcrank and slowing it down with a tall control horn. This gives you something to work with if you need more throw.

Brett Buck · « **Reply #25 on:** February 17, 2014, 09:43:44 AM »

Quote from: Paul Smith on February 17, 2014, 05:56:03 AM

I prefer using the outer hole at the bellcrank and slowing it down with a tall control horn. This gives you something to work with if you need more throw.

In general, maybe, but not on a Ringmaster. You might end up needing a 2" high control horn.

Brett

john e. holliday · « **Reply #26 on:** February 17, 2014, 12:15:51 PM »

So true.

Randy Snow · « **Reply #27 on:** February 18, 2014, 07:00:59 AM »

I'm hopping to have my scratch built RM at VSC this year - scratched it from a kit someone gave me years ago -- the kit has mahogany ply -- used the kit parts as patterns - and used the mahogany ply doublers - left the bell crank parts in the port doubler so it's a solid part with no engine cut out - did some odd weird rework for that LE having no solid stock to replace that HEAVY ROCK HARD stuff in the kit - even the fuselage was hard and heavy - had to use 1 1/2 x 1/16 for a > type TL -- like I said the only thing from the kit used were the doublers -- clear doped fuselage and tail ( fin,rudder,stab & elev.) using some antique coverite fabric on the wings - hope the decal is still good it's going on the port side wing -- strap gear --I put the kit parts in one hand -LE,TL,ribs & fuselage and my complete scratched RM in the other and the kit parts were heavier. anyway I saw this RM post and thought I'ld add something

55chevr · « **Reply #28 on:** February 18, 2014, 11:01:00 AM »

I remember the mahogany doublers now that you mention them. I thought they were cut for a different kit and put in the wrong box because they fit so badly. Is a Ringmaster eligible for OTS if the parts actually fit?

john e. holliday · « **Reply #29 on:** February 19, 2014, 07:33:26 AM »

I think I have built maybe three of the original Sterling Ringmaster kits and the parts fit was as good or better than some kits I have built.

Brett Buck · « **Reply #30 on:** February 19, 2014, 10:19:06 AM »

Quote from: 55chevr on February 18, 2014, 11:01:00 AM

I remember the mahogany doublers now that you mention them. I thought they were cut for a different kit and put in the wrong box because they fit so badly. Is a Ringmaster eligible for OTS if the parts actually fit?

That's probably to your advantage, since then you are inclined to replace them. They are *utterly useless* as supplied, and if you actually use them, there is a very high chance that the engine comes loose on the first 3-4 flights as the wood compresses from 3/32 to about .005.

Brett

Andrew Saunders · « **Reply #31 on:** February 24, 2014, 04:43:14 PM »

Heres the latest pics. I still have to do some filling, sanding, hinge and attach the elevator , finish the adjustable tank mount, all before covering and paint. CAnt wait to get it done.

afml · « **Reply #32 on:** February 24, 2014, 09:50:15 PM »

Look'n Good!

Don't scratch the hood with that landing gear....

Can't wait to see the design on the covering.
With the increase of your 'Air Force', ya gonna need a bigger SUV or a trailer to haul them all!
Keep up the great work & "Tight Lines!"

Wes

john e. holliday · « **Reply #33 on:** February 25, 2014, 08:50:49 AM »

Your Ringmaster is looking good. Did you stay true to Eric's instructions? I have his kit plus an original S-1 Ringmaster I used for creating my Ringmaster. In finishing stages now. Monokote wings and Rustoleum color.

Forgive me for using your post. jeh

Bill Little · « **Reply #34 on:** February 25, 2014, 09:00:32 AM »

I really like the LE sanding jig Eric included in the kit. It really helps with the chore of shaping a built up LE. It can be used on other models since the shaped LE piece is pretty common on other models.

BIG Bear
RNMM/AMM

Andrew Saunders · « **Reply #35 on:** February 26, 2014, 05:16:12 PM »

Hey John. Yeah i stayed true to Erics instructions on building it.

john e. holliday · « **Reply #36 on:** February 27, 2014, 07:53:15 AM »

Should fly great then.

Sean McEntee · « **Reply #37 on:** February 27, 2014, 10:09:24 AM »

What Eric said is true. However, an additional 1/32 ply "shear web" is, in my opinion, nessesary. I built one of the kits in 2007, built per the plans and with an L&J fox 35 ('Murcia!). After around 600-700 flights, it developed a stress crack just outside of the center sheeting on both wings. When failure appeared to be imminent, I cut into the wing and added the 1/32 ply and the problem was resolved. You MAY be alright wih just a 25 on it, but I would suggest it if you want your ringmaster to live a long life

As for the controls, I used all supplied hardware in the kit. The kit comes with a 1/8 plywood horn that was stock with the sterling kit, as well as a longer plywood horn. I used the longer one and used the bottom hole.

Mine came out around 27 oz. It's up to 30 now after years of oil absorption. Have won several OT contests with it, and it even has a few classic wins and +500 point scores to its credit. Very good flying airplane.

Brett Buck · « **Reply #38 on:** February 27, 2014, 10:24:25 AM »

Quote from: Sean McEntee on February 27, 2014, 10:09:24 AM

What Eric said is true. However, an additional 1/32 ply "shear web" is, in my opinion, nessesary. I built one of the kits in 2007, built per the plans and with an L&J fox 35 ('Murcia!). After around 600-700 flights, it developed a stress crack just outside of the center sheeting on both wings. When failure appeared to be imminent, I cut into the wing and added the 1/32 ply and the problem was resolved. You MAY be alright wih just a 25 on it, but I would suggest it if you want your ringmaster to live a long life

The failures we have seen with the stock original design (usually remade with 5-lb balsa instead of the original 18-lb) have all been at exactly this point. You definitely need to put something there to keep it together.

The problem has proven to be far worse with 15FPs, Veco 19's, and the like, than it is with a Fox. I suggest that the only reason it lasted 500 flights and then just had a stress crack is because it had a Fox. Many of the failures were with high rev/low pitch engines like the Veco 19, and they failed at well under 100 flights in most cases. The cornering loads are just too high without some reinforcement. Eric is exactly right to put something to reinforce it at that point and for sure, do not leave it out!

Brett

Douglas Ames · « **Reply #39 on:** February 27, 2014, 10:42:12 AM »

Quote from: 55chevr on February 18, 2014, 11:01:00 AM

I remember the mahogany doublers now that you mention them. I thought they were cut for a different kit and put in the wrong box because they fit so badly. Is a Ringmaster eligible for OTS if the parts actually fit?

Fellow clubmember De Hill says they were cut from door panels back in the day.
Makes sense, I lived in a couple houses that had interior hollow mahogany doors.
Same stuff, really cheesy "3-ply".

Author Topic: RSM OTS Ringmaster (Read 6433 times)

Mike Griffin