PylonWorld

Cost has always been given as the reason for not allowing all molded composites in 424. When a Chinese made composite is released in the $150-200 range, what's the argument against them then?

BTW, the molded composite Swee' Pea tail I'm doing is suitable as a stab for any Q-500 "woodie" and will be available separately. I may wind up offering wings in a couple of different airfoils for very reasonable prices.

Doing ones own all molded composite is not a Herculean task. It just takes some time, learning, and effort. It can easily be done for the cost of a couple of Vortex airframes, or a trio of NEME-Q's.

I've even considered offering molds for sale, so that people who favor molded composite construction can make their own.

stand-RCU

Are we suggesting here that one chop up someone else's product and copy their hard work and knowledge?

I know Sam San is working on his own design and has tried several different wing configurations of his own design and would not appreciate someone taking a short cut when he comes up with a final configuration.

Myself, I can't imagine copying someone else's work; If I can't ramp up knowledge of engineering required, I'd be ashamed to steal someone elses hard work and effort.

I do make a Q-500 that Jim Allen and Gary Schmidt designed, but I have their templates and permission to do so for our Speedworld R/C club members.

Stan D.
N75E

PylonWorld

Stan,

I did a LOT of prototyping, testing, and spent a lot of time studying existing techniques and even came up with my own new way of building composite wings and tails.

In terms of the NACA 66-012 (or any 66 series airfoil) or the MH-18B, anyone who uses these airfoils is "stealing" the work of others. That is the nature of aerodynamics and aircraft in general. Think about the anniversary we are celebrating this year.

The Swee' Pea tail that I'm doing simply mimics the outline of the original Swee' Pea tail with 6.5 more square inches of surface, and has internal versus external torque rods. It is a simple slab stab and like I said, it could be used on just about any Q-500 woodie.

The fuselage for The Smasher was designed in 2000 before I even saw a NEME-Q. It is based on the design principles of the Lancair (Lance Air, for those who don't know how to say it) 320, 360, III, IV, and Columbia, the Cirrus SR-20/22, and the tail placement is based on a Beech study of the optimum placement of a V-tail in the propwash slipstream for yaw control.

The Smasher is as much my original work as any other Q-500 is someone elses. And I do expect it to be extremely successful.

One other thing Stan. Of all of the designs in Q-500 and Q40, every one of them borrows from previous designs. In fact, Mike Del Ponte sat down with me at the 2002 NATS and told me the lineage of the current most popular planes. They all have borrowed elements from each other. In fact, at one of the JR races last year, one manufacturer held up a stab from another manufacturer's plane, and said "this is what I'm using for my next XXX stab".

And another thing. At some point in the future, I will be seen flying Smashers with a ventral fin and rudderlet. I'm not going to give the secret behind the motive, but I will tell you that even though Jimmy Allen used a small rudder on the first of the Quik-V's, the full size Swee' Pea had a rudderlet added shortly before it became the Sky Baby in the late 40's to early 50's. In addition, some of the first Beech Bonanza V-35 prototypes had a rudderlet also.

PylonWorld

BTW, I did not start this thread ... it was started by someone else who subsequently deleted his posting.

Mluvara

My Feedback: (10)

Maybe I'm wrong, but I believe Don's original post meant that the cost of making a set of molds is the cost of buying a complete composite airframe or two. Just a comparison of cost.

Michael

PylonWorld

You are correct Michael. What I was saying, and thought that would be clear, is that for an investment of $1200-1400, you can make your own set of molds for an all composite plane. For each aditional plane you do, the cost is an additional $200-300. And the cost even includes the cost of the tools to make everything.

I'll even break it down:

9-10" Drill Press - $100
9-10" Band Saw - $100
16" Scroll Saw - $100
1" Belt Sander - $70
FeatherCut with 26" and 52" bows - $240
Home Built Power source for foam cutting $40
Vacuum Bagging Kit - $350
various epoxy materials - $200
various fiberglass materials - $200
Time - About 500-1000 hours

Total $1400

Other things needed that I didn't count in the cost because you should have them in your shop regardless:

Sandpaper
Incidence gauge
Calipers
Etc

And then you're ready to produce each plane for a materials cost of $30-100 each depending on materials used.

You will then have a well equiped model shop, and you can create new versions or new planes easily.

I used to spend up to a 100 hours building a single control line speed plane in my Junior and Senior days. So the time is not unreasonable. I would rather have spent the time practicing, but the benefit of having cheap planes is that I will be able to practice hard and often.

Here's a picture of one of those 100 hour planes that set a Senior 1/2A Proto Speed record

PylonWorld

I left off one set of tools you need if you are going to do all molded composites. But you need this set of tools if you are going to fly Q-40, unless you want to pay someone to paint your planes.

You need a compressor and a spray gun.

Even though it is possible to spray a racer with an airbrush, don't buy an airbrush compressor, unless you have a good reason. Home Depot and Wal-Mart sell a Campbell Hausfield oil-free 13 gallon compressor that delivers 6.9 SCFM @40 PSI and 5.5 SCFM @90 PSI for a little over $200. If you don't have a compressor, there are lots of non-plane related uses that make it easy to justify to the better half.

I now have 4 spray guns ranging from an $8 external mix airbrush I bought at Northern Tool (Harbor Freight and Tool, etc), a $60 Paasche Internal Mix Airbrush, a $30 DeVilbiss Detail gun (Lowes Home Improvement), and a $200+ HVLP Sata MiniJet III.

Guess which one I use the most? The $8 airbrush. Using the primer and paints I'm using, cleanup is a 2 minute affair. I would like to thank Scorpion Jack Hamilton for turning me on to the NELSON Hobby Specialties line of primer and paint. These products are actually manufactured by System Three Resins and both the epoxy primer and the paint are water reduceable and water cleanup. And the epoxy primer sands at least as good as the old K&B epoxy primer did.

When you start molding planes, one thing you have to deal with is getting the molds separated from the plugs, and the parts separated from the molds. An airgun with 90+ PSI behind it is a wonderful tool for the job. In fact, with a non-migrating release agent like FreeKote 700, one blast of air can often pop a part right out of a mold.

Pylonwheels

I've Been watching here for a while now, isn t this the plane that you copied from another guy??? Prety bold to build it into a composite when there's no flight data available and according to the AMA rule book you can t compete with this plane in 424 and doubt it ever will because APRA and AMA have the same rules.

Pylonwheels

js3

My Feedback: (3)

Pylonwheels,

As it reads now, there is NOTHING in the AMA rulebook that says composite airframes are disallowed or illegal. You've been misinformed.

js3

My Feedback: (3)

Pylonwheels,

In addition to my last post, the current AMA rules will be valid until 2005. Dan Kane has submitted a proposal that would modify the existing rule to disallow composite/molded-winged airframes in AMA 424 but again the current rules are valid until 2005.

That is unless his proposal is made an "emergency" rule change and implemented prior to the standard rules cycle.

PylonWorld

Pylonwheels,

Postings like your message to me will no longer be allowed in the PylonWorld forums. Personal attacks are going to be deleted. The only reason I'm not deleting your message is that it is going to be left as an example of what WILL NOT BE TOLERATED anymore.

My plane is my own work as much as anybody elses Q-500 is their own work.

In terms of "no flight data", re-read my sentence "I did a LOT of prototyping, testing, and spent a lot of time studying existing techniques and even came up with my own new way of building composite wings and tails."

js3

My Feedback: (3)

I find it funny when people claim that so-and-so copied a particular Q500 design. If Don's plane is a copy of John Doe's design, whose design did John Doe copy his from? Joe Schmo perhaps? And then where did Joe Schmo get his design? And on and on and on...

I don't know what the first shoulder-winged, V-tailed Q500 racer was. The first one that I knew about was the Kwik-V by Jim Allen back in the early 1990s.

All Q500 planes that utilize a V-tail and have the wing mounted on top of the fuse are variations of the same airplane!

By the same token, anyone who builds their own shoulder-winged, V-tailed quickie and claims that it is completely original is simply deluded!

PylonWorld

John,

From what I've been told, Mike Del Ponte was the first to use a shoulder wing, at least competitively. And if I have the lineage correct, he added a V-tail shortly after JA, and renamed the plane the ReVlution.

PylonWorld

Another very useful tool for making all molded composites is a profile gauge. This one is from Woodcraft and is a somewhat expensive German made plastic one. However, Micro-Mark sells one that is 6" long, but two can be joined together to make a 12" gauge. They call theirs a Contour Gauge and it serves the same purpose. You can also find profile/contour gauges at the home improvement stores, but I haven't seen any at retail that are long enough, or can be joined to be long enough, for wing roots.

These gauges are invaluable for determining the true inside dimensions of hollow core molded wings for making the spar and structure that support the skins. They are also very useful for regular model building. It makes it much easier to precisely shape matching wingtips, etc.