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General control line discussion => Open Forum => Topic started by: Paul Raley on June 08, 2025, 06:48:43 PM

Title: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 08, 2025, 06:48:43 PM
What would be an ultimate engine choice for a Brodak kit Ringmaster?  Is it true that Joe Gilbert uses a B25?  Does he run it in a wet 2?  I have the normal stash of Fox 35's, Veco 19-29-35, Merco 29, McCoy RH 40's etc., but I am not sure any these would prove to be a killer combo with the Ringmaster.  Maybe a 15FP?  Recommendations?  TIA!
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: john e. holliday on June 08, 2025, 07:13:50 PM
If you do a search on Ringmaster you will see all kinds of answers to your questions. D>K
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Steve Helmick on June 08, 2025, 08:02:09 PM
How heavy is it going to be? We had an OTS guy that built a series of Ringmasters from fresh scratch, from 16 oz with a .15FP to 20 oz with a .25FP. The .15FP one was the best until the wind got over about 5 mph. A Veco .19bb is a pretty good choice, if yours is one of those. A .20FP or .25LA would be great. IMO, the weight in oz. should be pretty close to the displacement in 100th of a cubic inch, so 19 oz for a .19, 15 oz. for a .15, etc. No, it won't fly well at 35 oz.!  D>K Steve
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 08, 2025, 08:18:29 PM
How heavy is it going to be? We had an OTS guy that built a series of Ringmasters from fresh scratch, from 16 oz with a .15FP to 20 oz with a .25FP. The .15FP one was the best until the wind got over about 5 mph. A Veco .19bb is a pretty good choice, if yours is one of those. A .20FP or .25LA would be great. IMO, the weight in oz. should be pretty close to the displacement in 100th of a cubic inch, so 19 oz for a .19, 15 oz. for a .15, etc. No, it won't fly well at 35 oz.!  D>K Steve
Thanks Steve!
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Mike Hazel on June 08, 2025, 09:15:25 PM
What Steve said!  My S-1 Ringmaster with LA 25 weighs 25 oz. 
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Gary Dowler on June 09, 2025, 02:49:41 AM
What would be an ultimate engine choice for a Brodak kit Ringmaster?  Is it true that Joe Gilbert uses a B25?  Does he run it in a wet 2?  I have the normal stash of Fox 35's, Veco 19-29-35, Merco 29, McCoy RH 40's etc., but I am not sure any these would prove to be a killer combo with the Ringmaster.  Maybe a 15FP?  Recommendations?  TIA!
If built reasonably light , no rudder offset creating unnecesary drag, etc, then a 15FP will work perfectly.
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Dan Berry on June 09, 2025, 11:36:36 AM
Joe runs a Brodak 25
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 09, 2025, 03:27:32 PM
Joe runs a Brodak 25

Thanks Dan.  Have you seen him fly it? I was wondering if he does a 4-2 or a wet 2 with the B25?
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Dan Berry on June 09, 2025, 05:09:09 PM
Thanks Dan.  Have you seen him fly it? I was wondering if he does a 4-2 or a wet 2 with the B25?

Be assured he lets it sing. 9/4 Apc prop.  57 ft lines.
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: C.T. Schaefer on June 09, 2025, 06:57:39 PM
Here is my input.  Brodak S-1 kit. Poyspan/dope. B25 9.5x4.5 apc. 10%. 58x.012. 25oz. A very nice flying plane. My pal uses the FP20 also very nice.
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Motorman on June 09, 2025, 08:05:27 PM
I had an RSM Ringmaster with a Veco 19 BB and it was my favorite plane for some time. The 4-2-4 on that engine was magical. It finally wore out and now has an LA25.

MM :)
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Colin McRae on June 09, 2025, 08:34:43 PM
I have a McCoy 35 on mine. I like the nostalgia of an old-style engine on an old design model. But that is just me. And I prefer the McCoy over a Fox, again just me.

Won't win trophies, but fun to fly, nonetheless.

A side benefit for the McCoy 35. I have a lot of 29% castor oil fuel I need to use up.  ;D
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Dave_Trible on June 09, 2025, 08:50:19 PM
I've had only two Ringmasters.   The first one as a kid of about 11 years with a Fox.   I remember it flew really well.   I wouldn't be afraid of a Fox on one now.   Plenty of power and still very light weight.   The second I build I have now, really a Super Ringmaster,  same airplane with a built up fuselage.  It is powered with a Johnson .35 and is fun to fly.   Old airplanes, old engines go together fine.   Ringmasters are really for-fun airplanes and not serious competition.   Put on whatever engine interests you to mess with.


Dave
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 10, 2025, 07:26:44 AM
Thanks for all the great recommendations.  That is just the sort of first hand feedback I was looking for.
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Martin Quartim on June 13, 2025, 01:30:26 PM

Enya 15CX  True ABC,  4,76 Oz with 2BB

That is what will power my next RM S1.

https://www.ebay.com/itm/226379964953

Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Mike Griffin on June 14, 2025, 10:37:02 PM
Veco 19  BB.

Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Peter in Fairfax, VA on June 16, 2025, 10:00:01 AM
I like the .012 lines idea.  Though I lost a nice Fox 35 Nobler circa 1976 trying to fly with badly kinked .012s over asphalt.  My principal mentor had taught me about lines, by my teen self hadn't heeded that advice well.  You can fly with .012s, but they must be in excellent shape.

Peter
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 16, 2025, 02:11:21 PM
Veco 19  BB.
I do have a nice Veco 19 BB.  Probably a 9-4 prop?
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Brett Buck on June 18, 2025, 12:09:33 AM
I do have a nice Veco 19 BB.  Probably a 9-4 prop?

   9-4 or 10-4. We have tested it back-to-back with the 20FP, the FP is slightly more powerful at high RPM, the Veco can make that up because it handles larger props better. Also, it will be very fast either way. Jim Aron's 20-point Ringmaster (the RSM kit box art model) ran about 4.2 second laps with an APC 9-4 and 60 ft lines. We swapped in a 20FP, and it went 3.8. This with the usual setup for both, STOCK 20FP including all parts, Veco 19BB-CL, stock venturi, "stock" HB muffler, 10% nitro, etc.

    The speed solution for Jims case was to depitch the 9-4 to about 3.6. Still pretty quick but the speed is so steady that it is very pleasant to fly.

     Brett
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Dennis Toth on June 18, 2025, 10:38:58 AM
I like the Veco 19BB with a tongue muffler and a trimmed 10 x 4 prop. My lap time comes in around 4.65sec which is close to what Joe Gilbert was at Brodak. He uses the Brodak 25 and it seems to be running just lean 2 cycle. Maybe Joe could jump in and give some prop details.

Best,   DennisT
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 18, 2025, 01:59:54 PM
I like the Veco 19BB with a tongue muffler and a trimmed 10 x 4 prop. My lap time comes in around 4.65sec which is close to what Joe Gilbert was at Brodak. He uses the Brodak 25 and it seems to be running just lean 2 cycle. Maybe Joe could jump in and give some prop details.

Best,   DennisT
I like the sound of that.  Did you trim the 10-4 down to 9-4?  Was it an APC prop?
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 18, 2025, 02:08:06 PM
I like the Veco 19BB with a tongue muffler and a trimmed 10 x 4 prop. My lap time comes in around 4.65sec which is close to what Joe Gilbert was at Brodak. He uses the Brodak 25 and it seems to be running just lean 2 cycle. Maybe Joe could jump in and give some prop details.

Best,   DennisT
Do you recall where you got the tongue muffler?
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: EricV on June 18, 2025, 02:39:50 PM
What would be an ultimate engine choice for a Brodak kit Ringmaster?  Is it true that Joe Gilbert uses a B25?  Does he run it in a wet 2?  I have the normal stash of Fox 35's, Veco 19-29-35, Merco 29, McCoy RH 40's etc., but I am not sure any these would prove to be a killer combo with the Ringmaster.  Maybe a 15FP?  Recommendations?  TIA!

Well, I can tell you what NOT to use... like a McCoy Series 21, in the .35 or .40 size with a heavy brass tank and solid rubber Williams Brothers wheels n~... not if you plan on doing vertical 8's anyway... heh. Mine done up in Sig Koverall in orange and black as a kid with a McCoy series 21 was a wee bit nose heavy (Ok, a LOT nose heavy... and I have no idea what it weighed on a scale, who weighed planes back then? I only weighed the fish I caught, and then heavier was better! LOL!) and no doubt had stock control ratios per plans, so V8's were not my friend.  HB~> LL~ But I sure thought it looked cool!  8)

My Yak9 with a Fox .29 flew MUCH better, heh. Funny the things we thought were hot stuff back then as teens. Both planes built on my desk in my childhood bedroom using kits, my one piece of sandpaper, single edge razor, Ambroid, Elmers, and moms iron whenever heat shrink covering was involved.  n~

Joking and memory lane aside, I concur with the others on the Veco 19... just slow that elevator ratio down a bit and keep the weight off it best you can and it should be fine.

EricV
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Dennis Toth on June 18, 2025, 04:52:20 PM
Paul,
For starters, use a good base fuel with say 10% nitro, 25% total oil (50/50 mix is OK for the Veco), use a full APC 10x4 with the engine set to a just lean 2 cycle (not on the edge of 2 cycle in it) to set your baseline (you may need to go in a couple clicks once you see how you engine/tank/prop work after launch). If it is too fast (a good target lap time for a Ringmaster is 4.7 sec on 60 ft C to C lines) de-pitch the prop to 3 3/4" if de-pitching is not your thing try switching to a Master Airscrew 10 x 4 (they are a bit lower in pitch than the stated pitch, might need to try the MAS 10 x 5 if too slow). If too slow, trim the prop diameter 1/8" at a time (adjust the needle to maintain the just 2 cycle setting) till you get to the speed you like with the engine at a happy setting (for getting close just cut and fly once you are in the ballpark try to maintain the smooth tip shape and balance). You can then fine tune the lap time with nitro %.

Best,    DennisT
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Joe Gilbert on June 18, 2025, 06:49:26 PM
B 25 ,9x5 APC prop , dyed black ,what I ran at Brodaks was  20 percent nitro 18 percent KL 198 oil , in dead air I like it beaping when when maneuvering when little wind moving  just run in hard four stroke all of flight. Aircraft weighs 22.5 oz I fly it on 57 foot .12 lines. Hope this helps.



Regards
Joe Gilbert
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 19, 2025, 11:41:21 AM
B 25 ,9x5 APC prop , dyed black ,what I ran at Brodaks was  20 percent nitro 18 percent KL 198 oil , in dead air I like it beaping when when maneuvering when little wind moving  just run in hard four stroke all of flight. Aircraft weighs 22.5 oz I fly it on 57 foot .12 lines. Hope this helps.



Regards
Joe Gilbert

Thanks Joe! 
Title: Re: Engine Recommendation for Brodak Ringmaster
Post by: Paul Raley on June 19, 2025, 11:46:35 AM
Paul,
For starters, use a good base fuel with say 10% nitro, 25% total oil (50/50 mix is OK for the Veco), use a full APC 10x4 with the engine set to a just lean 2 cycle (not on the edge of 2 cycle in it) to set your baseline (you may need to go in a couple clicks once you see how you engine/tank/prop work after launch). If it is too fast (a good target lap time for a Ringmaster is 4.7 sec on 60 ft C to C lines) de-pitch the prop to 3 3/4" if de-pitching is not your thing try switching to a Master Airscrew 10 x 4 (they are a bit lower in pitch than the stated pitch, might need to try the MAS 10 x 5 if too slow). If too slow, trim the prop diameter 1/8" at a time (adjust the needle to maintain the just 2 cycle setting) till you get to the speed you like with the engine at a happy setting (for getting close just cut and fly once you are in the ballpark try to maintain the smooth tip shape and balance). You can then fine tune the lap time with nitro %.

Best,    DennisT

Thanks Dennis.  That is a great plan for speed control.  I definately learned something here.