spitflyer-RCU

I'm about to start my first scratch building project-the 76" Lazy Ace by Chuck Cunningham. I've built several kits todate, Four Star 60, GP TCraft, old Sig Kadet Mark II, but this is my first venture from plans. I've ordered a load of balsa and cut a batch of spruce sticks on the table saw, so I'm ready for action.

Any suggestions from you experts out there on things to be aware of, to watch out for or to do with regard to this particular model or scratch building in general. Thanks for the opportunity to dialogue.

Rodney

I did not build it from plans, a friend did and crashed it so bad he was sure it could not be rebuilt. anyway, I took the pieces, put them back together and powered it with a Magnum .91 4 stroke. It is now one of my favorite planes and is a superb flyer. The only change I would make is to put a 1.20 on it as, since it gained weight in the rebuild, will not hover with the .91. It will land at a walk, flys hands off inverted with no down elevator required and will do most of the manuevers I attempt except for the tumble. I think you will love it. Just be sure to keep the wing incidence as per plan, a slight variation in the upper wing incidence can transform a plane from a dog to a pleasure to fly.

scale buff

My Feedback: (24)

You've picked a good model to start scratch building. It builds great and flies great. Just be sure to build it straight, which isn't too hard to do and to keep it light. Don't know what you intend to use for power, but I fly mine with an OS 1.08, mainly because I let it get too heavy at fifteen pounds. If you keep the weight at around 12 pounds and use a .90 two stroke or 1.20 four stroke, you'll have a delightful airplane. If you've never cut wing ribs, this airplane, with a flat bottom air foil is perfect. I would cut two templates from 1/8 ply, lite or regular, and drill two 1/4 inch holes, one toward the front and the other to the rear. Cut your blank balsa ribs, match the flat bottom and cut a hole, using a sharpened piece of brass tubing with an outside diameter of 1/4 inch. This gives a better hole than a drill does. After all the blanks are cut, place them between the two templates, held together with 1/4 dowels. Now you can start carving the top, since the bottom is already done. When you get close to the templates, start sanding. Be careful not to sand into the templates. I always use a black magic marker on my templates, and when I see some of the black sanding away, I know I'm done.
Use a disc sander or a razor saw to cut the leading and trailing edges.

Good luck!

Rodney

Offline, I think you have the wrong Lazy Ace, the one mentioned is the small one 76" span. You are talking about the large one which I also have. I have a Quadra 41 on it and it weighs 18 pounds, my 76 inch version with the Magnam 91 only weighs about 8 pounds, maybe 9, I have not checked the weight for sure. Either one flys great. Rod

Navigator-RCU

Hey Spitflyer,

I just purchased the plans for the 62" Lazy Ace Biplane. All my research led me to this plane from Chuck. Everyone I talk to said it is an excellent Biplane. I think we made a good choice. This is my first plan building project too. For Christmas, my wife bought me the Harry Higley's BIPE book. It's all about building and setting up biplanes. An excellent book. Very professional and precise. A lot of attention to details. I am just starting to collect all the wood needed for building. I am planning on using a 90 4-stroke on mine. The instructions said this size engine was a good match. Probably a Saito. I think the Chrome valve covers will look good sticking out the side of the cowl. Fiberglass Specialties has cowls for these planes. I'm getting one for mine from there. Pretty good engine too.
How are you planning on transfering the plans to the balsa wood?
Carbon paper and tracing? I like the suggestion for cutting wing ribs.

spitflyer-RCU

Hi Navigator,
I just received my order of balsa to start on the Lazy Ace. I'm also in the middle of a Dynaflite Chipmunk so I'll have to juggle the two. I had the plans copied so that I could cut out the components (ribs etc.) from the plans and glue them to some material to make the templates or to cut out the actual component. One of the more experienced members of the NG mentioned using a color marker to outline the component on your balsa. Then, after you cut a little oversize, you sand until the color is gone. I'm going to try that process. I have a G23 gasser that I hope to use on either the Ace or the Chipmunk.

scale buff

My Feedback: (24)

Rodney, I wish I had made a mistake, but I didn't. I was talking about my 76" Lazy Ace. I made some mods to the plane, fairing the nose to a 4" spinner, adding a dorsal fin and wheel pants. I covered it with fabric, and painted it with Sig dope. One of the mistakes I made was in spraying white dope over white fabric. It never looks like the paint is covering, so I kept on spraying and spraying. It looks good, but I added a pound, just in the paint. I also was careless in monitoring the weight of the tail while building, consequently, after it was covered, I needed to add a pound of lead to the nose to balance. Hence the almost fifteen pounds it ended up being. If you have access to back issues of RC Report, Bill Skipper printed two pictures of it in his column in the May 1997 issue.

kevin mcgrath

My Feedback: (1)

I have built three aces,in two sizes,including one the same as yours.As pointed out by others this is a very good first "build from plans" project(no way Im getting into the definition of scratch building!),since the fuse is a simple box,and the wings flat bottomed and constant chord.I use the two template method of making constant chord ribs,and it works well.I used a ST .90 on mine,which was a perfect match.If I built another in this size I,d use a 1.20 4 stroke.
A few suggestions: Dont fool with the soldered wire LG.Suggest you find a formed aluminum one of approx the same dimensions .Check the SIG catalog.
Cut the fuse off at the firewall and mount the engine sideways.Make yourself a fibreglass cowl using a foam plug.This way you sidestep fuel soaking into the wood cowl,and the whole model looks much better IMO.
Consider scrapping the wire cabane structure.I did on my last "BIG" Ace ,repalcing it with an ultimate single beam setup supported by four aluminum uprights.Much stronger,cleaner,and no solder joints to look after.
As long as you get the CG in the right place,and the incidence of the wings correct ,this will be one of the most delightful models you will ever fly.
Incidentally try to keep the weight under control.Mine balanced without ballast,with the servos in the standard place.Id use your favorite iron on plastic for the wings,and fabric and paint on the fuse........
All above IMO,and my $C.01 worth........

For clarification there are kits or plans,avail for four sizes of ACE I beleive,and the one you are building is the original,which was detailed in RCM,years ago.
By the way,if you try an outside loop,do it at least 3 accidents in altitude,cause that flat bottomed airfoil doesnt seem to want to tuck under.at the bottom of the loop.......

Rodney

The 76" Lazy Ace I have does not have a flat bottom airfoil, it is semisemetrical. The large one does have a flat bottom airfoil. One unusual characteristic of the 76" version I have is, when you go inverted, it flys level hands off with no elevator trim. The only other plane I had that did this was the 40 sized Phaeton from Balsa USA. Both a real pleasure to fly. Rod

spitflyer-RCU

Thanks for the information Kevin. All of this is going into my Lazy Ace file. I hope to start building soon. I'm currently working on a Dynaflite Chipmunk. My order of balsa and ply for the Ace arrived from Lone Star last week so now I have material to work with. This should be interesting. I hope to use a G23 gasser for power.

scale buff

My Feedback: (24)

Rodney, I'd have to disagree with you. I've built all three of the large Lazy Aces (which excludes the smaller 62" version). The original Lazy Ace, published in RCM, was 76" and has a flat bottom airfoil. The Super Lazy Ace, which has a span of 96", is an exact copy of the original. Chuck Cunningham added a Big Lazy Ace, with an 84" span, which does have a semi semetrical airfoil. It also has a much different shaped stab, elevators, fin and rudder. There is a vague similiarity between it and a Stearman, mainly in the tail group. I believe the plans are still available for all three from Sky Master Industries in Fort Worth, Texas

kevin mcgrath

My Feedback: (1)

Well...we might as well beat this subject to death.Everything in the last input is correct...The original Ace is the 76" version and was published in the November 77 issue of RCM...Im sitting looking at a copy of this issue.I also have a set of Sky master plans for the 84" big lazy ace,and as a matter of fact this plan has both a flat bottom airfoil,and a semisymetrical, and templates for both,builders choice.It also has two options for the tail feather shape,the original and the rounder shape,with an airfoil stab,which is the one I used.If I ever build this size again,Ill try the semi airfoil,and put ailerons on both wings.Im flying this current one with a Quadra Q400 which is 39cc and this is a perfect match IMO.I have had five different engines in this current model (31cc weeder conversion,ST 3250,Quadra 35,Zenoah G62 and this current Quadra).
One other mod spit.....dont use the monkey motion bellcrank setup for the ailerons.Just bury one servo in each panel and connect it to the aileron with a short straight 4/40 pushrod.Syncro them if you have a computer radio,or use a reversing "Y" harness in the aileron channel if you dont.....

Navigator-RCU

I have started making the wing ribs for my 62" Lazy Ace. I want to keep the plane as light as I possibly can. Just as Kevin suggested. 10 of the ribs require having holes in them for the aileron wires to the servos. Will it be OK if I put these holes in all 44 ribs to save that weight and the wing still remain strong? I read to use aircraft plywood ( stronger) for the firewall instead of balsa ply. Is this a good idea? I am planning to use the Klett main landing gear, do I need to put toe-in on this, if so how do I do this?

Thanks

kevin mcgrath

My Feedback: (1)

Holes in all the ribs isnt going to make any appreciable difference in strength or weight either.Most of the strength in the wing is dependent on the design and constuction of the spars.Make sure the holes are big enough to easily fish the servo lines through.I stack my rib blanks about 10 at a time and use a hole saw in a drill press for this job. Installing rolled tubes of newspaper works well,but make sure you install these before you join the wing panels,and put on the wing tips.The biggest weight savings (insert BIG IMO !),is using plastic iron on covering, particularly for the wings,(I prefer Ultracoat),being careful about how much epoxy glue you use,and watch the paint build up if you go this route on the fuse.
I would not worry too much about toe-in at this point.More important is no toe-out, and the placement of the gear in relation to the CG.Using an easy thumb on the throttle,and learning to use rudder during and after the takeoff is a must.However,the design is not in the least squirrly regarding ground handling,and tail high takeoffs are easy and pretty.I think your first takeoff,and full stall landing will make you an Ace fan for life!
Im not sure what you mean by balsa ply,but make your firewall out of the 5 or even 7 ply wood sold by your LHS,or places like Balsa USA.
Feel free to keep the questions coming,but lets do it in this forum,not E-mail.Im sure there will be other opinions on some of these subjects,and that is all to the good.