Author Topic: Ringmaster 576 Electric. (Read 4406 times)

John Rist · « **on:** January 16, 2013, 01:26:33 PM »

I have started building a Dee Rice Pat Johnston's 576 sq" Ringmaster. I will be building it as an electric. First step was the molded leading edges. See photos. I will post as it goes.

John Rist · « **Reply #1 on:** January 16, 2013, 06:54:27 PM »

PS when wrapping the 1/16' balsa to the ribs with the ace bandage don't wrap it too tight. It will deform the balsa between the riblets. Ask me how I know. I gets to redo one of the leading edges.

Dennis Adamisin · « **Reply #2 on:** January 16, 2013, 07:09:17 PM »

Aw shucks (yeah, thats the word)

Been looking forward to someone building an Electric 576.

THANKS in advance for the thread, and keep those picutres coming!

John Cralley · « **Reply #3 on:** January 16, 2013, 10:14:39 PM »

Dang John,

The instructions should warn you about not over doing the wrap!! Frustrating to learn this the hard way!

john e. holliday · « **Reply #4 on:** January 17, 2013, 09:37:48 AM »

I have seen where instead of the Ace bandage, use strips of old linen sheet or towels.

John Rist · « **Reply #5 on:** January 19, 2013, 08:59:59 AM »

Leadind edge and main spar are finished. The main effort was to keep them straight. The spar was the hardest to get straight. Most balsa sticks are not very straight. I cut this one from 3" sheet stock. I spliced the spar between ribs R5 and R6 on both sides rather then in the middle. The splices are 45 deg angle cuts under the carbon fiber cap strips.

Looks like I will have to reshape ribs R1 and R2 a little to accommodate the 1/16" sheeting of the center section.

All in all it is going really well so far.

John Rist · « **Reply #6 on:** January 20, 2013, 11:13:31 PM »

Wing is coming along nicely. So far it is straight. The flaps will be a bear to shape. They are tapered in two directions. They are carved out of a 1/2" thk balsa board.

john e. holliday · « **Reply #7 on:** January 21, 2013, 08:57:01 AM »

Sounds like some custom made jigs for sanding are in order. Looking great with that construction. May have to think about getting one for myself.

Dennis Adamisin · « **Reply #8 on:** January 21, 2013, 04:08:56 PM »

Looking good John!

I would be tempted to tack-glue the flaps in place and carve them on the wing...

Crist Rigotti · « **Reply #9 on:** January 21, 2013, 05:57:48 PM »

Yeah, it does look good!

John Rist · « **Reply #10 on:** January 22, 2013, 12:30:06 PM »

Quote from: john e. holliday on January 21, 2013, 08:57:01 AM

Sounds like some custom made jigs for sanding are in order. Looking great with that construction. May have to think about getting one for myself.

Wow! Now that I think about it a sanding jig is the answer! Thanks John.

John Rist · « **Reply #11 on:** January 22, 2013, 09:04:30 PM »

My new scale came in today. Wing as pictured above weighs in at 185 g or about 6.54 oz.

John Rist · « **Reply #12 on:** January 26, 2013, 11:07:07 AM »

Follows is a brief description of how I built the sanding fixture for the ailerons. First of all, per the plans, I cut out aileron blanks from ½” balsa. I then built the sanding fixture. The base of the fixture is ½” sheet rock lying on a flat building table. This provided a flat surface for the fixture.

Photo DSC_0033: determine the thickness of the ailerons at the 4 corners. Create gage blocks per these thickness and using the aileron blank as guide glue the block to base.

Photo DCN_0034: Cut two filler block the same size as the aileron from ¼” plywood. Place the filler block between the gage blocks. This filler block will raise the aileron up the ¼ inch needed to match the gage block rails.

Photo DCN_0035: Cut 4 each 1” wide by ¼” thick plywood rails. Glue one of the rails to the gage blocks.

Photo DCN_0036: Glue the second rail to the other gage blocks.

Photo DCN_0037: Place the balsa aileron blank in the fixture.

Photo DCN_0038: Build a mirror image fixture with remaining parts. Sand the aileron to shape using a sanding block. Sand a little at a time flipping the aileron between the two fixtures to keep the aileron symmetrical. Mark a centerline around all 4 edges of the aileron to act as a guide.

john e. holliday · « **Reply #13 on:** January 27, 2013, 06:47:29 PM »

Nothing like a little ingenuity and thought to do it right. Looks great.

John Rist · « **Reply #14 on:** February 07, 2013, 09:53:12 AM »

Well I finally made some progress on my Ringmaster. The wing is ready for the top sheeting to be installed.

John Rist · « **Reply #15 on:** February 07, 2013, 02:33:22 PM »

Wing is now finished ready to cover. Top and bottom sheeting, control system, wing tips, weight box and leadouts are all installed. This wing assembly weighs 10.3 oz.

John Rist · « **Reply #16 on:** February 09, 2013, 05:16:39 PM »

Well I am well into completing the fuselage. This is where it starts to look like an E-powered Ringmaster. A big thanks to Walter Umland for designing and laser cutting the E version of a front end (BuiltRight-FlyRight). He did a ton of design work and laser cutting for very little money. Also picture is Bob Hunt's G-10 fiberglass motor mount. Another great product at very low cost. I plan to use a combintion of the G-10 mount and the wood mounts. When done I will post pictures.

The tail wheel as pictured on the Ringmaster drawing is neat. It is a floppy tail wheel that rotates. It is built and ready to plug in. After the airplane is covered I will epoxy it is place. I will check balance before I install it. If I need tail weight I will pour lead shot in the hole before I plug in the tail wheel

John Rist · « **Reply #17 on:** February 10, 2013, 06:43:57 PM »

Fixen to mount the motor mounting ring. The drawing calls for 3 deg out thrust and zero deg down thrust on the glow motor version. I plan to use a pusher prop. Do I use the same offset for an electric motor?

John Rist · « **Reply #18 on:** February 11, 2013, 01:01:35 PM »

Thanks Ty, Makes sense. One point - this is not you grandmother's Ringmaster - This one ain't small, it will have 576 sq in of wing.

John Rist · « **Reply #19 on:** February 11, 2013, 09:58:22 PM »

Motor mount is installed. It is made from Bob Hunt's G-10 fiberglass motor mount and two of the laser cut rings from Walter Umland's E conversion kit. The inner wood ring was cut back to clear the motor. The G-10 glass ring was cut to shape using a wood ring as a pattern. The outer ring was cut back to clear the prop adaptor. The 3 were laminated with epoxy by bolting and clamping together.

This assembly was then glued into the noise of the ringmaster. I used 1 deg out thrust and zero deg down thrust. Two support blocks were glued to the outside of the ring and two were glued to the inside of the motor rings. The noise was then sanded to shape. The pictures tell the story.

Crist Rigotti · « **Reply #20 on:** February 11, 2013, 10:01:10 PM »

Looks good John.

John Cralley · « **Reply #21 on:** February 11, 2013, 10:27:09 PM »

Looking good John,

Skimming this thread I did not see that you have mentioned what electric setup you are planning to use with this 576. I think that most of us are using 4S or 5S batteries on larger planes and I see you have a 3S in one of your photos. With a 3S you will need a higher KV motor than the 700 to 1000 or so KV motors that work well with 4S and 5S batteries. I assume that you have this in mind.

I am also a bit worried that you will come out really nose heavy with this plane. With my S-1 Ringmasters I found that the battery needed to be mostly behind the leading edge of the wing to get a proper CG. Ringmasters have a rather short tail moment. You might want to temporarily install the electronic components, tape on the tail feathers and do a test CG estimate. Yes the wing and covering will change it somewhat but you can get an idea. For mine I cut out a portion of the outboard wing and made a battery mount that allowed moving the battery to adjust CG. I will attach a photo of my S-1 setup.

With all of that said, you may turn out just fine with your current setup given that the 576 is a flapped model and the S-1 is not.

John Rist · « **Reply #22 on:** February 12, 2013, 07:54:08 AM »

Quote from: John Cralley on February 11, 2013, 10:27:09 PM

Looking good John,

Skimming this thread I did not see that you have mentioned what electric setup you are planning to use with this 576. I think that most of us are using 4S or 5S batteries on larger planes and I see you have a 3S in one of your photos. With a 3S you will need a higher KV motor than the 700 to 1000 or so KV motors that work well with 4S and 5S batteries. I assume that you have this in mind.

I am also a bit worried that you will come out really nose heavy with this plane. With my S-1 Ringmasters I found that the battery needed to be mostly behind the leading edge of the wing to get a proper CG. Ringmasters have a rather short tail moment. You might want to temporarily install the electronic components, tape on the tail feathers and do a test CG estimate. Yes the wing and covering will change it somewhat but you can get an idea. For mine I cut out a portion of the outboard wing and made a battery mount that allowed moving the battery to adjust CG. I will attach a photo of my S-1 setup.

With all of that said, you may turn out just fine with your current setup given that the 576 is a flapped model and the S-1 is not.

You are correct. At this time I need to do a CG check. The 576 Ringmaster isn’t really a Ringmaster, it just looks like one. I am not sure how the tail moments compare to the S1.

The battery in the picture is a 4S. The picture has the notation 35 – 70 C. At a glance it looks like 3S – 70C. I will be using a Cobra 2820/12 @ Kv 970.

John Rist · « **Reply #23 on:** February 12, 2013, 08:15:39 AM »

I just did a CG check. It did come out noise heavy. However most of the covering and a bunch of hardware (push rod tail wheel etc) are yet to be added. Almost all of the covering is aft of the CG. I think it will be close.

John Cralley · « **Reply #24 on:** February 12, 2013, 08:33:06 AM »

Quote from: John Rist on February 12, 2013, 08:15:39 AM

I just did a CG check. It did come out noise heavy. However most of the covering and a bunch of hardware (push rod tail wheel etc) are yet to be added. Almost all of the covering is aft of the CG. I think it will be close.

Sounds good. The 576 should be a great flying profile as an electric!!

John Rist · « **Reply #25 on:** February 15, 2013, 12:45:58 PM »

Body covered in carbon veil. My first time to try this. Actually it goes on quite easy. Also sands nicely. Right now I am leaning toward a rattle can finish on the solid wood surface and Ultra coat on the wing. What's best in a rattle can paint? Wood has Brodak butyrate dope on it.

PS Ty gave me carbon veil - Thanks.

John Rist · « **Reply #26 on:** February 20, 2013, 10:22:24 PM »

Body ready for paint. Plan to paint less wing.

Dennis Adamisin · « **Reply #27 on:** February 21, 2013, 05:12:06 AM »

Looking mighty fine John!

John Rist · « **Reply #28 on:** February 22, 2013, 11:54:59 PM »

Wing Decal

John Cralley · « **Reply #29 on:** February 23, 2013, 11:10:01 AM »

The decal looks nice John!!!

John Rist · « **Reply #30 on:** March 09, 2013, 05:32:16 PM »

Well the body is ready to mount the wing. Looks OK at 20' - but then I was never good at putting on a finish. But then this airplane is intended to learn electric and how to fly stunt. Good looks is the least of my worries!!

Bill Little · « **Reply #31 on:** March 11, 2013, 04:30:16 PM »

Hi John,

The 576 is a great flying stunter! I will be interested in how it turns out with your power system. Just take the time to trim her out right.

BIG Bear
RNMM/AMM

John Rist · « **Reply #32 on:** March 11, 2013, 08:42:08 PM »

Quote from: Bill Little on March 11, 2013, 04:30:16 PM

Hi John,

The 576 is a great flying stunter! I will be interested in how it turns out with your power system. Just take the time to trim her out right.

BIG Bear
RNMM/AMM

Good advice! One problem - I don't have a clue what I am doing. The good news is I do have lots of help in my flying club. When I get her going I will list my setup and all of the happings.

John Rist · « **Reply #33 on:** March 28, 2013, 02:47:29 PM »

Well the Ringmaster 576 is ready for it's first flight. I am a much better photographer than I am builder. Hopefully the stuff that matters is good. I believe it is built straight. Up close the finish is a little rough. But no matter the intent is to learn stunt so this one may be short lived.
Specifications are as follows:
Airplane: 576 Ringmaster by Dee Rice and Pat Johnston.
Wing area 576
Weight ready to launch 47 oz
Electric conversion kit by Walter Umland
Motor mount by Bob Hunt (G-10 hard noise)
Motor Cobra 2820/12 KV= 970
Speed Controller eBay special 60 amp compatible with Turnigy Programming card.
Timer KR with RPMs set at 9200.
Prop APC 12 x 6 EP
Static amp draw = 32 amps.
Battery Turnigy Nano-Tec 4 cell 2650 mah
Plan to start out with 62" lines.
Photos attached

Dennis Adamisin · « **Reply #34 on:** March 28, 2013, 06:37:22 PM »

John
That is a TERRIFIC Ring 576! Pat & Dee should be proud of ya. Your power system is spot on, its gonna fly great. CONGRATS on a great project.

john e. holliday · « **Reply #35 on:** March 29, 2013, 09:35:34 AM »

Hey it looks great and I hope it flies as well as it looks in the pictures.