I just built an Ace 4-60 and it is HEAVY. I don't have the instructions for it and the plans don't show CG. If I support this thing at the main spar, it is seriously tail heavy. It has an OS Max .60 FSR in it mounted all the way to the front of the engine mount beams and both the battery and receiver are mounted against the bulk head between the fuel tank bay and the radio compartmentcan't get them any further forward. And it STILL hangs tail down. Does anyone know where the CG is supposed to be? If it's supposed to be somewhere around the main spar, I'm gonna have to put an anvil in the front of it to achieve balance.

Shoot for the main spar in the wing, almost all manufactures balance on the wing spar, aprox 33% the chord.

My 4-60s balanced on the main spar. One had an OS 91 Surpass for power, the other an OS 61 two stroke. Balance was achieved without adding additional weight.

You may want to go to a larger battery, to aid in the balance. Moving the servo tray forward will help, too.

I had this same problem on my Bingo, which is the low wing version of the 4-60. You're right. It took quite a bit of weight to get it balanced, and the model flew "heavy."

In my 20 plus years of flying, the Ace 4-40 and 4-60 were my favorite models to fly, second only to the Ace Taylor Craft. I'm building one of those, at the present time.

Tom C: By "bigger battery" do you mean going 6 volt or do you mean using same voltage cells but bigger physically, like C cells instead of AA size? It's kind of an intriguing thought just to upsize battery size rather than add useless weight.

Max

What ever you feel comfortable with, sometimes going to 6v will make servos jittery, especially if you have long servo extension wires, twisting the wires helps to control the issue a little but not too much, just go for a heavier pack to ballance or relocate the servo tray more forward, but you'll end up having to build new pushrods.

Max, I was referring to going from, say, a 500 ma battery, to a 1300ma battery, at 4.8 volts. I think they a sub-C cells.

By using them in this size model, you gain useful weight, and will seldom run out of battery during a full day of flying.

I suggest trying this first. Then test the balance. You never know, it may be enough. If not, then relocate the servos.

In the end, you may still need to add nose weight, but it won't be nearly as much, after making these changes.

I have the Ace 4-60 plans - the sideview of the fuselage does show the CG at the main spar.
I took mine off with my close-up glasses on once, and of course couldn't see it past the end fo the runway. The last time others saw it, it was coming down nose first in a slow roll. Landed on an unpaved street away from the field, tore off the gear and broke the prop. That's all - sometime the R/C Gods smile upon us. Enjoy yours, Eloy

Tom C: Balancing this puppy right on the main spar required 15 oz. of weight between the engine and firewall. I did that by melting a bunch of split shot lead fishing weights and pouring it into a pepper can. The resultant bar of lead fit beautifully between the legs of the engine mount, against the firewall behind the engine. I put a pair of blind nuts inside the firewall and bolted the bar of lead to the firewall so it can be easily removed. I had just ordered a couple of sub C NiCads from Interstate Batteries for my glow starters. Meantime, I am going to weigh the old sub C from one of the glow starters and if they are significantly heavier than the AA cells, I will order four more and make a battery pack which will allow me to reduce the lead ingot somewhat. I really dislike the idea of that bar of lead between the engine and the firewall. And EloyM, I am certaninly happy that yours wasn't damaged any more than it was. Sometimes, good things do happen to us in spite of ourselves.

Wow, nearly a pound of weight !!! I hope the larger battery pack helps to alleviate your problem.

Will you be able to move your servos forward ?

He did say "interstate batteries", I'm guessing a group 42 battery will ballance it out just right, and think of the benifits, you'd never have to ask yourself if the reciever battery has enough juice to fly, I think you could get the 600 cca model and be fine for the whole season!

TomC: I considered moving the servos forward, but it would be a lot of work for very little gain. As far forward as I could move them would put the front of the group just about under the CG. Since the whole thing only weighs about 4-5 ounces, I'm not sure how much good that would do. And making all new control rods really doesn't really appeal to me. I guess everyone has one operation he hates the most in kit building and making control rods is the one I hate most.

planebuilder66: That is funny. I know you're thinking the same thing I did when I first googled "batteries" and Interstate Batteries was one of the choices. I immediately thought "automotive batteries". But I opened the site and found that they sell just about every kind of battery known to mankind. I'm not pushing themthis is my first order with thembut I thought I'd give them a try. If this doesn't work, maybe you have an old group 42 lying around that I could try. I'll bet that would bring the nose down.

Max

I don't blame you for not wanting to make new linkages. I hate the "fiddly" stuff too..