R. Ortiz

Hi, I am scratchbuilding a SuperKaos 60 from plans. I would like to assemble the wing on a home built wing jig (just like the Great Planes or RCM wing jig) that has two rods going through holes on the ribs. My problem is that the plans call for some washout and I wonder how this can be done on a jig built wing. I would greatly appreciate any suggestions.

speedracerntrixie

My Feedback: (29)

Build it without the washout!!!! There is absolutly no reason to have it except to ruin the inverted performance of an airplane that should be inverted often.

All Day Dan

My Feedback: (5)

You don't need that washout for any reason what so ever. Build the wing without it. Dan.

BMatthews

The SuperKAOS isn't the sort of wing where I'd expect any washout either. Are you sure you're not thinking of something else? Like the tip rib is thicker to build in "aerodynamic washout"?

In any event the way to do that is to stack the ribs, drill the first hole for the forward guide rod. Then with a rod through that hole you'd "fan" the rest of the ribs evenly and then drill the second rear hole. Repeat identically for the other side. YOu'll need to do this using some sort of ruler or other guage to ensure each rib is evenly graduated. But that's the simple way of doing it. Otherwise the risk of laying out and any error building up is far higher.

kdc

If the rods are held down to the base with wing nut or similar then you just pack up the rods by the correct amount ( adjusting for building inverted if needed)

Build to the plans though. Looking at the plans it seems there are 3 trailing edge blocks which vary in height to allow for the smaller ribs near the tip. It is not clear if this produces washout. Assemble the ribs on rods and measure the TE height to see if it agrees with the plans block heights. The instructions suggest using the RCM jig and the holes are positioned on each rib so it should work OK.

Note that the RCM wing jig details are still online here http://www.rcmplans.com/index.php?main_page=page&id=18 together with many other useful articles. All the Kaos and many other aerobatic plans and instructions can be downloaded from here http://www.trentonrcflyers.com/patte...structions.htm

R. Ortiz

Thank you very much for the info. I will build it without washout. I was thinking that the different sized blocks on the plans were used to create washout, but now that you mention it, I can see that they were used to keep the smaller wings level with the bigger ones. I am new at building from plans so please pardon my ignorance.

kdc

Feel free to ask any further questions and someone will be pleased to answer them I am sure.

I think this plan uses a notched trailing edge like many of the Joe Bridi designs. I found it easy to notch trailing edges using 2 or 3 hacksaw blades bolted together to cut a notch of the correct thickness. Each of my hacksaw blades cuts a 1/32 groove ( varies depending on teeth per inch and worn or not) so 3 bolted together cuts 3/32 etc. A bit of tape makes a handle. Then a simple wooden jig allows the cuts to be all the same depth.

The plan I have shows the Leading edge in 2 ways, the ribs are shown for a flat LE while the section at the fuselage shows the 3/8 sq LE in a 'diamond ' shape notsch. . If you make the ribs flat you might consider laminating the leading edge from several layers and lapping the sheeting over the first layer as shown in my diagram.

kdc

Leading Edge diagram with different colours to show different layers. Note this is not specifically for a Kaos but any model. Glue used should be sandable otherwise it 'pulls out' when sanding to shape. The inner layer is glued on first and then lapped with the sheeting with a tiny overlap. When glue is dry the sheeting is sanded back flush and the front layer is then glued on and shaped when dry.

Campgems

The build rods don't have to taper, but could be parallel. That means make your stack of ribs and while they are together drill two holes through the stack. Just make sure that they are not under a spar .

Don

Bax

My Feedback: (11)

The Bridi Kaos and Super Kaos did not have any washout in the wing panels. They did have double-tapered wings. That means when you build the wing on a flat board, you must prop up the leading and trailing edges. Because of the wing's taper, the tip airfoil is smaller than the root airfoil, so the tip must be propped up with bigger blocks than the root. A bit of examination will show you why.

You could also eliminate using different-sized blocks under the leading and trailing edges if you use oversize strips for the leading and trailing edges. Mark the centerline of each piece so that the ribs can be properly-centered on them. Then plane and sand to the correct dimension once the ribs have been glued on.

donnyman

R. Ortiz

Using the build jig you mention it is easy to put washout in a wing, just lift the rear wing tip end of the rod enough to get the washout you need.

turbo.gst

My Feedback: (8)

I think you will find that the Super Kaos flies well with no wash out. It settles down and makes slow, nose high landings routinely.

Adding washout is very easy with a jig. I drew all the wing rib templates on top of each other in reference to the center line. Mark the wing jig holes on the template. I made copies and used 3M 77 to attach template pattern to each rib pair and drilled the holes. Super easy and excellent results. I have since used that method to build tapered wings so that the top is flat and the bottom tapers ( experimenting with dihedral / yaw ). I have been extremely happy using that method with my jig.

Enjoy the Super Kaos!