Q-500 Sheeted wings and foam cores for sale
 

While this has been posted in bits and pieces in other threads, I'm going to use my one thread per week allowance as an advertiser to create a thread specifically about my Q-500 foam cores and sheeted wings.

I'm cutting foam cores for the 66-012 and the S8064 Viper 500 airfoil now. I will be cutting the 65-012, and some others very soon.

My white foam cores are $10 each and are 47.75" long.

I'm also cutting pink foam cores that weigh about 2.2 ounces more per core. But they are very stiff and will build into a stiff wing. They are $15. I think that using 3/4 ounce glass under the skins on white cores may be a better option, but these are available for those who want to try them.

Go to [link=http://www.stegallhobbies.com/Q500/Cores/Cores.aspx]Quickie 500 Wing Cores[/link] for more information and shipping cost.

I'm also sheeting wings in a variety of configurations. The prices range from $70 to $125. Custom configurations are available. Like if you you want a Super wing with a balsa leading edge, that is no problem. See [link=http://www.stegallhobbies.com/Q500/SheetedWings/SheetedWings.aspx]Quickie 500 Sheeted Wings[/link].

Shipping sheeted wings internationally has been a problem as shipping anything over 38" long is a big problem. The Extreme Two Piece Wing is a design I came up with to deal with international shipping. Guys from around the world are wanting sheeted (or RTF) wings. I've never seen a foam 2 piece wing. But I figured out how to use the spar in the Extreme Wing along with carbon fiber tubes and rods to make a wing that can be glued back together and have the center section glassed. It will still be plenty strong for even 428. It will be priced at $125.

RE: Q-500 Sheeted wings and foam cores for sale
 

I know you're not supposed to share company secrets, but I learned how to slot cores from Jim Katz and I refined the concept for production purposes. So I'm going to show how I slot spars for the Super wing and prepare it for sheeting.

Here is the bed I made to lay the core into.

RE: Q-500 Sheeted wings and foam cores for sale
 

The core is laid in the bed and the jig is placed on top.

The jig is lightly clamped down. Just enough to hold it in place.

Then the router is run down the slot.

RE: Q-500 Sheeted wings and foam cores for sale
 

The slot is vacuumed clean and the other side is done.

Then the trailing edge feather is trimmed off. When I first started shipping cores I did not trim this off. I do now because I realized while talking to someone on the phone that most people don't have 48" or 60" straight edges. If you don't have them and you are going to be sheeting wings or building wings, go to Home Depot and buy you some. They are only $10 to $12 and will save you a lot of frustration dealing with too short of straight edges.

RE: Q-500 Sheeted wings and foam cores for sale
 

To get the core ready for sheeting, I prepare the bassword spars. I pick which side I want to be the bottom and mark the bottom with a magic marker. Then I hit the edges of the bottom with 100 grit to take the sharp edges off. This makes it much easier to slide the spar into the foam.

I slide the spar into the foam using finger pressure. I only try to get it within 1/16" or so. I don't want to cause any depressions on the foam core.

Then I use a wide blade screwdriver at an angle and start in the middle pressing the spar even with the core. If you start on the ends, they will wind up too far in.

Then I tack the spar in using foam safe CA on each side every 1". This is a lot easier than trying to use wood glue or epoxy and the main thing is holding the spar in place to join up with the carbon fiber laminate going over the top of it.

RE: Q-500 Sheeted wings and foam cores for sale
 

I had capacity issues as I could only produce one sheeted wing per day. Plus it tied up my foam cutting table. I got my 30" x 60" x 1/2" piece of glass on Thursday 3/12. Got it set up on Friday and got my T rig reconfigured for easy bagging with two bags.

I sheeted two wings on Saturday and will be taking them out later today.

RE: Q-500 Sheeted wings and foam cores for sale
 

The two wings came out great. Straight and no problems whatsoever. The leading edge is pinched tightly around the carbon fiber.

Wings will be flying out of here now. :D

Here is a Super photo for me. Three Super wings ready for shipment to another vendor. All three came out at 11.2 ounces after trimming the ends, leading and trailing edges.

RE: Q-500 Sheeted wings and foam cores for sale
 

Thanks for sharing Don. Very interesting!

RE: Q-500 Sheeted wings and foam cores for sale
 

Here's the easy way to cut carbon fiber laminate to size.

Mark where you want to cut it with a bright gel pen. I use pink.

Tape it down to your cutting surface with masking tape.

Use a 48" straight edge and put tape on the ends of the straight edge to hold it in place while you cut.

Cut with a sharp utility knife.

Lift the tape off the cutting surface and reposition the straight edge to the next position.

This is much easier than trying to hold the straight edge in place by hand. Invariably you will let it shift and your piece will not be straight. You should still hold down the straight edge while you cut, but it is much easier to keep it in place this way.

RE: Q-500 Sheeted wings and foam cores for sale
 

I'm using so much 50K carbon fiber tow that I bought a 4 pound bolt of it with approximately 1600 feet. If you need a small quantity like 20 feet, just contact me. I'm getting ready to buy a 4000 foot roll of 12K tow.

RE: Q-500 Sheeted wings and foam cores for sale
 

I've been working hard all day and need a physical break, so I'm going to post a little documentation of the sheeting of a Super wing.

For all steps when I say a "pump" I mean one pump of WEST 105 resin and one pump of WEST 206 hardener which is a little under one ounce by volume.

* I mixed a pump of epoxy and drizzled it on a skin.

* Using a 3" foam roller I spread the epoxy on the skin.

* The skin with the epoxy on it plus 19" of 3/4 ounce cloth overlapped 1/2" in the middle.

* no photo - Mixed another pump and did the other skin.

* The skins with 2.5" of 1.4 ounce cloth on the trailing edge. Epoxy was lighly brushed where the laminate spars go. Then on top of the spars. Do it now so you don't forget and have no bond to the core, or hardwood spars.

* The bottom shuck with porous release film laying in it.

* The bottom skin laid in the shuck with the rear aligned with the rear of the shuck.

* No photo - Epoxy is brushed on the hardwood spar in the core on the bottom to make sure it sticks to the laminate.

* The core is laid in the shuck and release film is laid on top.

* no photo - The top shuck is placed on and the assembly is filpped over.

* no photo - The bottom shuck is aligned and T pins are inserted about 1" from the ends behind the laminate. Then every 6 to 8 inches. The assembly is flipped back over.

* The plywood insert is placed on the trailing edge. First a very light amount of epoxy is brushed where it will go. Then a light amount is brushed on it. Also brush some on the hardwood spar.

* no photo - The carbon fiber tow leading edge is wetted out with another pump and placed on the front of the bottom skin.

* no photo - The top skin is put in place, the release film, then the top shuck

* Pins are put in place to hold the top shuck and skin in place.

* A close up of the pins.

* The whole assembly is wrapped with paper towels to act as breather and it is placed in the vacuum bag.

RE: Q-500 Sheeted wings and foam cores for sale
 

I now have the MH 17 in a 10" chord.

This wing should fit Bob Harris' Buckshot as it uses a very slightly modified MH 17 with a 9.9988" chord. Only a tiny amount of sanding of the saddle near the rear should be required for a perfect fit. It probably will work with no changes.

Gary James has been analyzing Quickie airfoils and has found the MH 17 to be very good on paper for both Quickie 25 and AMA 428 speeds.

So cores and sheeted wings are available now. I will have them on the web site in the next day or so.

RE: Q-500 Sheeted wings and foam cores for sale
 

Will you post a better pic of the tow leading edge please?

RE: Q-500 Sheeted wings and foam cores for sale
 

Vic,

I just got done with a couple of wings and I took a few photos.

* I wet out the 50K carbon fiber tow on an extra piece of plastic that will be disposed of.

* I squeegee the epoxy out as best I can

* no photo - I pick up the tow and form a rope out of it

* I lay it up against the core leading edge. While holding down the core I push it up against the foam and form the top so it will contact the top skin

* A close-up of the tow in place

The top skin is put in place. When the vacuum is pulled it pulls the skins together and the tow is firmly attached to both sides.

I initially cut the cores for a 1/8" leading edge. I found that hardly any CF was left on the 66-012 this way. So I went to a 3/16" LE. It takes more tow. I have to use 3 pieces. But a lot of it gets cut off. Then more gets sanded off when the leading edge is shaped. The weight comes down with each step. And enough is left over.

RE: Q-500 Sheeted wings and foam cores for sale
 

Got it!

Thanks Don.;)

RE: Q-500 Sheeted wings and foam cores for sale
 

Attached are drag polars of several common racing airfoils used in Q-500 at Reynolds numbers reflecting both Q-25 and 428 speeds. Dr Selig did a good job! Next is to take a look at 3D wings and see if there is an improvement available there.

RE: Q-500 Sheeted wings and foam cores for sale
 

I have been asked by Don Stegall to provide a little interpretation of the graphs that I recently posted. I can’t make you all aeronautical engineers in a few short paragraphs, but perhaps I can help you make sense of these charts.

There are two attachments. Each attachment has two graphs on the page. The first attachment is an analysis of the various airfoils at a Reynolds number (Rn) corresponding to Q-25 speeds. The second attachment is an analysis of the airfoils at a Rn corresponding to 428 speeds. There is no “mystery” about Reynolds number. It is simply a way to express the relative importance of kinematic (inertial) forces to viscous forces in a fluid. At low Rn’s ( i.e. low speed and small chord) viscosity becomes more important that at high Rn. That is, the air acts more like maple syrup at low speeds than at high speeds. That’s why a bumble bee can’t “fly”… actually it’s “swimming”. It’s necessary to take the effect of viscosity into account.

In each attachment, the “hook-topped” graph on the left is called a lift curve and is simply a graph of how much lift the airfoil section is capable of producing plotted against the angle of attack. You can see that the symmetrical NACA 66-012 produces zero lift at zero degrees angle of attack, which is what you would expect from a symmetrical section, and that the cambered MH 17 and S8064 each produce some lift at zero degrees. As you can see, the slope of all three lines is essentially the same, this is typical. All reasonably good airfoils are pretty much the same here. When then line “bends over” at the top, that is the stall. Some airfoils stall with a sharp drop off, while others are pretty mild. All three of these are typical. The higher the line goes before it drops off, the higher the lift the airfoil is capable of producing before it stalls. In both cases, the S8064 is capable of producing more lift before it stalls.

In each attachment, the “U-shaped” graph on the right is called a drag polar and is a plot of how much drag the airfoil produces for the amount of lift being produced. The “bottom” of the “U” is the minimum drag that the airfoil has. It can’t go any lower. As you can see, all three airfoils are pretty much the same. The difference is in the “noise level”. Moving to the right (we don’t care much about flying inverted or negative “g” in racing), the “flatter” that the “U” stays, i.e. the closer it stays to the lower right corner, the better the airfoil is for any particular amount of lift being produced. They are all pretty similar. At Q-25 speeds, the MH 17 and the N66-012 are pretty much equal, and the S8064 is a little better. At 428 speeds, the MH 17 and the N66-012 are pretty much equal up to about 11 degrees angle of attack and then the N66-012 is better. But the S8064 is still lower and closer to the bottom right corner, which means that it produces even less drag for the same amount of lift. Prof Selig did a real good job!.

Caveats: This is TWO DIMENSIONAL data, it’s not a wing. There is a LOT more involved in the real world than a simple 2-dimensional analysis. Also, it doesn’t take trim drag into account. The MH 17 has lower trim requirements than the S8064 which will affect the drag of an actual 3-dimensional wing mounted on an airplane in flight. So what is the “bottom line” about what all this means? I means that I need to practice more and that I’m going to buy a Viper replacement wing from Don…:D

I hope this helped a bit.

RE: Q-500 Sheeted wings and foam cores for sale
 

By increasing my capacity to 2 wings per day and by buying materials in bulk I have been able to reduce my prices on sheeted wings some. All of the wings are now $10 less than they were. I know that's not a lot, but in these tough times every bit helps. Sheeted wings now start at just $60.

One thing I have done is that I am now using 3/4 ounce cloth entirely under the skins unless requested not to. I'm using contest balsa to keep the weight down and even though the fiberglass adds .6 to .7 ounces to a wing, it adds a tremendous amount of stiffness to the wings. It adds 20+ minutes to making a wing, but I feel better knowing the wings are much stiffer and stronger. I think even the light wings would be up to 428 with cloth on the outside.

All of my wing customers have been happy. So if you need references, I'll see what I can do about getting comments from my customers.

RE: Q-500 Sheeted wings and foam cores for sale
 

I have a new wing available. it is called the MH17X. The X is for Experimental and for Hybrid/Cross.

The wing is a MH 17 at the root. At the tip it is an MH 17 that has been de-cambered and is symmetrical. The tips have 1/2 degree of washout and the leading edge is 1/16 of an inch higher than the root. This results in a wing that is essentially flat in thickness. It is about .020" to .030" over the minimum across the span.

This wing will fit the BuckShot and HoleShot by Bob Harris with no modifications. You could also get a wood Smasher pre-cut for the MH 17 or you can build your own. I will provide templates.

As stated this wing is experimental. It has not been flown. But computer models and work by others suggests that it might be a good wing. Some F2A Control Line Racing teams are using lifting airfoils at the root with symmetrical tips. Dave Norman has done something similar on a Quickie.

The symmetrical MH 17 was provided by a benefactor. I will leave his identity up to him. I appreciate the work he has done. :)

I will have it on the web site with pricing in a day or two.

RE: Q-500 Sheeted wings and foam cores for sale
 

I finally wore out one of my Quickie vacuum bags and had to make a new one for some wings I'm sheeting today. I know a vacuum bag is trivial, but I decided to make a quick video of how I prep the bag with the vacuum line. I'm also going to shoot video after dinner of sheeting a wing.

Here is the [link=http://www.youtube.com/watch?v=T-nC_hRhH9c]Making a Vacuum bag[/link] video.

[youtube]http://www.youtube.com/watch?v=T-nC_hRhH9c[/youtube]

RE: Q-500 Sheeted wings and foam cores for sale
 

Cool. Id be interested to hear how the wing performs.

Ive always wondered about this: The AMA 428 rules say "3) Chord: Constant for at least 47-1/2 inches of span. 4) Airfoil thickness: Minimum 1-3/16 inches for at least 47-1/2 inches of span." I was always under the impression Q500 wings had to be the same airfoil & same chord length along the span for 47.5" & any washout could only be accomplished by geometric twist of the chosen foil section. You have different root & tip sections, each airfoil individually meets the min thickness & they are blended linearly. So what does 'constant chord' mean? They may as well say constant chord LENGTH... and any section alongthe span must always be MIN 1.1875" thick? (ie anything goes in terms of shape, high point position etc as long as the min thickness is observed). Is that correct?

I tried googling 'constant chord' & its not really a clear definition, at least what I could find.

RE: Q-500 Sheeted wings and foam cores for sale
 

Yes, it is legal. Some people are already doing it. Dave Norman is one of them.

If you want to be a pioneer, get one of these. I've give you a good deal on it. Or you can get this one and a pure MH17 for $100 plus shipping. That way you can compare it to a "pure" airfoil.

I have one of Bob Harris' Holeshot Quickie kits that I will sell you if you want. I can get another. The kit uses the MH17 and the MH17X fits right on it.

RE: Q-500 Sheeted wings and foam cores for sale
 

I shot a video of the sheeting of a Quickie wing on 7/1. Processing the video takes a lot of computer time. Plus I edited the video so you don't have to watch all 2+ hours of the process.

This should be a 2 or 3 part series.

Here is the link to the [link=http://www.youtube.com/watch?v=x3W1Vi7uQjg]Sheeting a Quickie Wing - Part1[/link]

Part 1 is putting the epoxy and fiberglass cloth on the wing skins.

[youtube]http://www.youtube.com/watch?v=x3W1Vi7uQjg[/youtube]

RE: Q-500 Sheeted wings and foam cores for sale
 

The chord is the distance from the LE to the TE. By constant chord for 47 1/2", that means for that distance the chord has to remain the same.

So if your chord is 9 7/8" at the center, it has to be 9 7/8" for a minimum of 47 1/2". Airfoil, camber, and wash out or wash in can all be adjusted as long as you maintain the chord distance and the minimum thickness of 1 3/16".

Hope that makes sense.

RE: Q-500 Sheeted wings and foam cores for sale
 

Here is the link to the [link=http://www.youtube.com/watch?v=F4zQsd9rm2w]Sheeting a Quickie Wing - Part 2[/link]

Part 2 is laying in the bottom skin and the foam core.

[youtube]http://www.youtube.com/watch?v=F4zQsd9rm2w[/youtube]