The 24 year itch
 

Some how, some way I became the owner of a ACE Mach None "short kit". I think it was a prize for finishing 15th at a 15 contestant event.
The kit has a nice canopy and all the materials that ACE RC figured you would ever need to build the basic wing. I do not know if drawings were furnished...I do not see any here.
This kit has just sat on a shelf, unloved.... for possibly 20-24 years.
I've always liked the looks of the Mach None and the Pacer...but the styrofoam wing has always looked too "chunky" for my taste buds.
The time finally has come to build this thing the way I'd like to see it done. I've got a real light .15 engine for it, so I do not think deviating from the basic design [too much] will be necessary. The biggest problem will be figuring out how to install the engine so that the cylinder doesn't stick out so far to look obnoxious.
This will require mounting the engine sideways and avoiding taking any photos or video of the starboard view of the plane.
The revised formica templates were pinned to the ACE wing cores and it took about 1/2 hour of grueling sanding while wearing a respirator to sand off the foam that didn't look right to me.
The next phase will be sanding in some dihedral and preparing the 3 wing sections for the main spar.http://www.rcuniverse.com/forum/atta...mentid=1988062http://www.rcuniverse.com/forum/atta...mentid=1988063

Good move on the root mod the old rc gear may have needed the extra beef but them days are er 1/4 + century gone. What engine do you have in mind?

Well of course none other than everyone's favorite, the ZALP .15...

If this idea proves to be too stupid, then there is the ASP .12 which is truly a .10 sized engine and slightly lighter than the ZALP.

Zalp 2.5cc F1C Power F/F Competition Engine
So youre planning on building the plane into overpowered blistering blurr ball of methanol and prop wash. I see Hobby Club carries them for $400 ouchie are you going to use an RC carb to help tame the beast or just hang on to dear life while your heart races to 160 bpm matching the top speed?
:cool:

I agree --- the original airfoil thickness was about 15.5% I believe. Dropping the thickness to around 12.5% to 13% would be beneficial. It should add some speed and relieve the wing of a little weight.

Are you going to do a complete build thread. If you don't have the plans, here's a tiled set that may be of some use.

Yep. Make it fast but easy to see, easy to have fun with. With a APC 6.5 x 5 it will put out over 3 pounds of thrust. With only a little more than 200 sq inches of wing area, I'm tempted to add some chord to the wing...maybe an inch. What I'm wrestling with is to go with an unsheeted foam wing, or just use this foam wing to generate patterns for one made out of wood. A symetrical wood wing this thin is some work to do but I'm more sure about the results.
24 ozs RTF is doable and with over 50 ozs of thrust there should be room in the budget for an engine kill servo.
Andrew, thanks for those plans, they will help keep this project somewhat recognizable as an ACE RC variant..

Get a real strong spar for the Zalp. I folded up a few wings over the years even with .10's. The plane is expendable sometimes, but the receivers always seem to die when I do the wing fluttering to the ground, and the fuselage doing the full bore lawn dart dive.

Yes, the unsheeted foam wing idea allows a full depth hard balsa spar to be unlaid pretty easily.
A sheeted wood wing the same thickness doesn't allow the spar to be as deep unless you disrupt the sheeting.
Unsheeted foam with low temp covering is kind of unsightly after a few dents set in.
Sheeting these foam cores without having the "shucks" to keep things straight is risky.
Building all wood 'rib and spar' wings this thin means careful jigging. If I had light enough slabs of 1/2 inch thick balsa, I'd just go that route with a inbedded spruce spar.

My first high speed 1/2A ship was the Pacer. Two channels(aileron and elevator). A TD .049 was used. Wow! It was a hot rod! Second 1/2A was a four channel MachNone with 4 KPS 12 servos for full pattern ship ability. It sported a TD .051 with what I believe was a Kirn exhaust throttle. It didn't have great vertical due to the weight but flew fine. A .15 will launch it into space!

The FF and C/L Speed versions of these Russian .15s are $400 to $800. This combat version was $190 including delivery. It is so small that it was delivered to my mail box in the small US Postal cardboard envelope.
I plan on using a fuel line pinch to kill the engine. A HS 81 MG plus linkage will add about 3/4 ounce.
The engine I have here had a birth defect that effected how a cooling fin looks, so it was most likely sold at a discount. They are not more powefull than much less expensive .15s if you plan on using a 7 x 5 or 8 x 4 prop....but they are pretty compact and light for a ball bearing .15.
That said, a $30 ASP .12 is still hard to beat as the "perfect" engine to use if you want to hot rod these commercial 1/2 A designs. I'd say the .12 is 80% as powerful as the ZALP or the OS CVA, but
it's a .12 in a .10 sized case.
This project could kick off a "building spree" of Mach None / Pacer type hot rods if I can come up with easy enough ways to build them. I did a couple of DIY knock offs of ACE GLHs a few year's back that turned out worthwhile. One was built for a Cyclon .061, the other for a ASP .12
The GLHs really track well and are naturally fast...it was my 1st fast RC plane back in 1988 or so. It weighed quite a lot and used to push the poor TD .049s beyond their rev limits in steep dives. Most of the time obliterating glow plugs. It was such a unique model to build with techniques I'd never heard of. Imagine taping an elevator servo to the fuselage. It had really tiny control surfaces, too.
The Mach None shows 2 runs of strapping tape on the underside of the wing and even with just a TD .049 that gives me The Willies. Even if the wing doesn't break, I'll bet you get to watch it bow during pulls outs from steep dives.
ACE RC kits in the larger sizes were popular around here. The LHS always had a few in stock. I'd like to know what the sales figures were over the years for each kit they marketed.

CP the old ACE foam wings are stronger than they look. I built a whizzard one time with the wing flat and added ailerons. For some reason I covered it with iron on fabric. Probably because econocoat looks so bumpy on the glh wings I did back then. Anyway as expected with a medallion 049 it had a climb out of about 20 feet per minute. So next went in any Enya 09. That was ok for a while then I slapped on a FP 20. This was better but they didn't rev much. I ended up running an OS 25 on it which pulled it along quite smartly until I finally put it in hard a few years later. The point is I never snapped the wing in flight and God knows I tried. Might have been the fabric, who knows.

I use to order sets of triple taperd wings from ACE might be that that particular foam wing for a design I sold back in the 90's called the Stiletto some nic named it the Texas Twister I would use the full thickness with 25 size engines. Balsa sheeted wing with sorghums glue fully symetrical solid balsa tail feathers for max control. Egg shell fuselage designed for speed, sport, acro type fantasy scale open cockpit would hold a knife edge at 1/3 throttle.

I'll bet the fabric was the difference maker. In fact Tyvek might be a good one to try [since I've got some laying around].
I drew the wing plan tonight and drew the rib templates. It will be 7 inches at the root, 5 at the tip and 42 inches overall for 252 sq inches.
I'll need to order some wood for the spars and other bits. This wing will be all wood and I'll set the original foam chunks aside for a possible TD .049 powered version.
I used to fly with a guy who took some foam wing cores and cut a million hex shaped cells into every nook and cranny he could. He then placed hardwood reenforcements for retracts and wing mounting, sheeted the foam and did very minimal fiberglassing before Monokote. It was an amazing job he did on those foam cores with a hex shaped cookie cutter and some heat.

Rare New In Box 1962 Cox Special .15 C/L-F/F up for grabs 32mins left 117.00 at the moment

http://www.ebay.com/itm/151278514667...ht_1942wt_1174

I've always been happier with the wood wings on the mach none/pacers I've had. The last few I built with just under a 10% airfoil. RG 14 maybe? I was real happpy with those. Cut the wind great and still land nice. Last one was a leekie and tried a few motors in it. The leekie was faster than the td. While they are not as fast as a glh, the faster they go the better they track.

$171 for the .15...! It's still semi "usable" at that price. Not so if it went for $1710, but that's just me. Actually, if it was worth $200 I would think twice before using it.

Hllywdb beat me to the skinny woodie wing version..! Also the .25 version..!
Back when I first got into C/L Combat I got detailed info from a local flyer about how to build the foamies light enough and strong enough to compete. I didn't want to take the time to inlay the 1/4 x 1/4 spruce spars into the foam..plus it looked like too much weight. These airfoils were almost the entire thickness of the 2 inch thick foam, so I figured that they didn't need much reenforcing.
I decided to go with a full depth spar of 1/16" ply and a wrap of strapping tape around the full length of the wing [over the spar]. The covering was self adhesive clear plastic overlay material called Fascal..pretty good stuff and easy to apply. The planes flew great with the Fox .36 Combat Specials..until I would try the first hard manuever then "POP"...the wings just exploded. Every single plane in that batch was prone to the same deal. I was pretty dejected until one of the "veterans" came up and told me..."Hey man...If you don't fold one every now and then, you're probably building too heavy".

Yea thought your .15 size efforts may spurn on someone here to jump on it; or you might of wanted it. Moca sells the adapter head for glow plugs which can be re-threaded for a nelson plug. The guy on ebay sells an aluminum carb body for the .15 I have a few. The TD special has thicker cylinder walls and no ball socket so can be pushed quite hard. = }

I never knew they had a conventional rod version.
I don't have many engines, but I have too many that don't get enough exercise so I'm all set for now.

CP I may have done the thin airfoil and the 25, but you get to be the first to the the thin wood AND the hot 15 :) As to spars for the foam wings, we did some 1/2a size RC combat planes a while back. Ended up switching to leekie motors as so many of the guys had problems getting 4 surestarts all running at the same time. If you grew up learning bad words by trying to get cox reedies running, it was fine, but teaching old dogs new tricks is tough. Anyway, built the wings by glueing 2 pieces of 6mm foam together and running a hardwood spar embedded 1/2 way through each piece. Also did them with CF spars. Never had one snap even with some hot motors strapped on. The Fox 36 is a different animal. Mine would occasionaly fold a voodoo wing. Never was good at reading the section on "recomended control throws."

I measured one of my current Pacer wings and it is 37" span, 6" in the center and 4 1/2 at the tips. So your 42" and 7 to 5 should handle the 15 easily. You may end up bored and running a 25 with a pipe :) So leave room to move the battery back in the fuselage. Come to think of it I have quite a few planes with a 1000 to 1500mah NiCad rx battery all the way in the tail as I tend to opt for the Binford 9000 series motor option. I think that's what you're supposed to do with planes you win. I won an old Rimfire kit as a door prize at a club meeting. The box said use a Veco 19 to 25. I sheathed the whole wing and ran an OS 61 long stroke with a pipe. Was lots of fun for about a year until I had a control surface flutter for about 1/4 second before it self destructed. The price you pay for performance. Little problems become big problems in far less time than it takes to reduce throttle.

Electric motors and plenty of battery packs sounds like the best way to go. I had good luck with AP .061s because they started easily and the limited power was just right for some all day beer drinking sessions while sitting in lawn chairs and chasing crepe paper streamers.
For the handful who are looking in here and already know how to build a wing, you guys are dismissed. The rest of this post is to show the "low time builder" or the "ARFer" what a woodie looks like before sheeting the top surface.
This is all balsa except for the birch [or alder] dihedral brace that fills the void between the main spars in the center section. There is also a hardwood spar to help strengthen the trailing edge in the center section. The spars are "boxed" on both sides with 3/32" vertical grain balsa with the hope that this feeble bit of engineering will delay the inevitable moment when the wing suffers catastrophic failure during a high speed maneuver. I could CHEAT and bury a carbon fiber tube in this wing, or go to the time and expense to glass it...but I want to see if this minimal approach will do.
Like the man told me 24 years ago.."If you don't fold one every now and then....."http://www.rcuniverse.com/forum/atta...mentid=1988862The photo is submitted just to prove that this isn't an ARF.
ARFs make me BARF....lol....

Spar caps, shear webbing, D tube, rib caps, leading and trailing stringers, triangle braces, tip plates... what have I missed lol been awhile since I spoke the language of the wing. :rolleyes:

I have this NIB if you want to give it a try (free no charge). NovaRossi REX ref.12. I've been busy with some other non-RC projects so have not even bench run it.http://www.rcuniverse.com/forum/atta...mentid=1989563

It's rc carb just not installed in picture

Xanaphyst, I really appreciate the offer, but I've got too much unfinished business already. I've got a speed project started for the ZALP .15 on a flying wing that will easily take me into 2015 looking for "V-max".
Same goes for a .40 powered speedplane project that is ready to fly but took "back seat" to an automotive restoration.
Why don't you build a 28 inch delta for that and get some fun out of it...?

Progress report.....
The wing turned out pretty nice. It's a pretty good compromise between thin, light and strong. It looks out of proportion to the fuselage now...since it is 25% larger than the original wing.
The Hayes plastic engine mount looks like it has a whole lot of unwanted angle built into it. I'll have to check on that to see what is going on. Right now the photo shows a ton of right thrust..or I am not seeing straight..?
Now is the time to make the tail group, then take a step back to see how the whole package looks as a unit. I't's possible that I won't like it. If so, then this stuff can be set aside for a .061 engine version and I'll build a 10% larger fuselage as a more proportional companionhttp://www.rcuniverse.com/forum/atta...mentid=1990598http://www.rcuniverse.com/forum/atta...mentid=1990599http://www.rcuniverse.com/forum/atta...mentid=1990600http://www.rcuniverse.com/forum/atta...mentid=1990601 for this wing. My reasoning is that I want it to be recognizable as a Pacer and the big wing / big engine already seem to clash with that goal now that I have a chance to get a better look at this thing in the flesh.
No matter what, nothing that has been done so far will go to waste, but it might get "reallocated".

http://www.rcuniverse.com/forum/atta...mentid=1991367http://www.rcuniverse.com/forum/atta...mentid=1991368I should have sized up what the sideview would eventually look like before commiting to what size to build this fuselage. I just "eyeballed" the .15 and assumed it would look just fine on front of the standard size Pacer fuselage. After seeing how ugly the cowl outline would look [like a duck billed platypus] I then investigated what the ASP .12 would look like. As you can see, the aluminum mounted ASP .12 has the same foot print and bulk as the ZALP .15 so this fuselage will get set aside for a .074. I'm pretty sure a .074 could be worked in to the original clean lines of the ACE Pacer.
So, I ordered more wood from SIG and this time will draw up a nicely sized fuselage that looks right with either the ZALP .15 or the ASP .12
SIG is doing well with balsa sales they say...so it's always good to hear that there are builders who support them.