RE: DERIVATIVE, New 2X2
 

I've come up with a simple way to do that and assure alignment. Nothng will be opened in the fuse until the fuse comes out of the mold and nothing will come out of the mold until the fuse is completed. I will not elaborate further on this since it has not been done yet and is unproven. Next Winter, stay tooned

With most of my honey do's out of the way, I can now start building on the fuse in earnest next week. I've been pushing the firewall buid out since I wanted to get some running time on the ZDZ40 before making the commitment.

I am going to try something different on the wing, stab and rudder finishing. I will outline that approach in these pages soon.

RE: DERIVATIVE, New 2X2
 

Bladder

RE: DERIVATIVE, New 2X2
 

Not much running time on the ZDZ40F3A....been palying with my SAP180 and have been having a ball.

I put a DLE55 on a diet, removing about 100 grams. Down to 43 ozs which is very close to the ZDZ. The DLE is the engine of choice moving forward.

The firewall is being built and will support the new soft mount I built for the DLE. The weight of the complete powerplant, header and pipe included, is 1.8 kg which leaves little room for error for the rest of the airframe. But wing panels are light at 8.5 ozs each ready to cover. It is large at 1100 squares. Progress is slow because it's summer and flying comes first

RE: DERIVATIVE, New 2X2
 

Time to get going on this build in earnest.

The DLE55 experiment has gone exceedingly well. Terrific power, great brakes using a 20x12 3 blade Mezjlik, and oustanding noise suppression.
The set up is straight forward: DLE55cc, Hatori header with extension, ESComposites 55G pipe, own soft rubber isolation mount with two rubber layers, 20x12 3 blader as mentioned above, gasoline is Avgas 100LL/BelRay MC1 motorcycle racing synthetic at 50:1.

Decided to build a foam cutting jig and cut my own foam. This is a gravity fed system similar to others on the market that use gravity to cut foam. It turned out to be simple to actually do once I had figured out how to get root and tip chord ratios worked out. The foam cutter is hands-off. It isn't a CNC cutter; requires root and tip templates.

My foam panels are 36" in span, with a 22" root and 7" tip. The 3:1 ratio works exceptionally well in pattern. There are several key benefits which I won't go into...I've discussed that in other threads before, so readers of my scribble would remember what I mean. Panel areas are approximately 522 square inches each with fuse entrained area 160 square inches. Total area will be around 1180 square inches. It goes contrary to current pattern practice but what else is new

Stab area is 260 square inches. The tail volume coefficient I am working with is 0.6, very spritely

Laminated the firewall last night. Basic cross grained balsa, carbon cloth sandwich.

BTW- the cross grained balsa I bought came from Aircraft Spruce. It is ready sealed, a nice touch

RE: DERIVATIVE, New 2X2
 

Have decided to change it's name to a simple DELTA. Anyone with any math understands that significance

RE: DERIVATIVE, New 2X2
 

This is a rather large firewall, some 40 square inches, and weighs around 46 grams. The hard points are simple carbon tubing with the blind nut on a piece of 1/8" aircraft ply installed to the back. I remove a 2" x 3" section behind the carb intake for better breathing.

RE: DERIVATIVE, New 2X2
 

I am really looking forward to seeing this model in person. A truly incredible work in progress.

I hope you're taking some photos for us.

The new name sounds great. Delta is less nerdy, although there's still something in there for nerds as well.:D It won't elicit as many questions about the meaning of the name, which will save you some time.

RE: DERIVATIVE, New 2X2
 

Bob,

I fitted the engine last night. It's a surprisingly nice fit. I'll take a few snaps tonight and post. There is enough room for the CDI in the pipe tunnel

The fuse is particularly well suited to the landing gear I make. That installation and access will be a cinch. It will be a modified Wist Models configuration that I first put into my Aesthesis.

I have myself almost convinced to build in an adjustable stab along with adjustable wing.

RE: DERIVATIVE, New 2X2
 

Here are some photos
The small lengths of carbon tubing were cut from standard 1/4" X 5/32" tube. The 5/32" hole is a near perfect fit for the 6-32 mounting bolts.

RE: DERIVATIVE, New 2X2
 

Matt,

Simply, WOW. The craftsmanship is obvious. Wow again.

This is one helluva project. Can't wait to see the finished result.

The way it's canted, nobody will believe there's a 55cc under the hood.

Hope you can keep it at 5kg. Those 3-blade gasser props are comparatively heavy.

RE: DERIVATIVE, New 2X2
 

The engine is slightly canted to get more of the header in the fuse. I will need to fit the header in the chin cowl at some point

The mount has been well wrung out in my extra. It works fine. Weighs 4 ozs flat except the stand offs add another 1 3/4 ozs. The hole in the firewall has not presented any problems so far in other planes and it makes sense for these rear intake engines

The 1/16" ply spacer is tack glued to the spinner backplate and the ply is tack glued to the fuse...standard stuff for veterans, but not so for newbies. Hope this helps you figure it out

RE: DERIVATIVE, New 2X2
 

Doing much of the fitting off the plane really works better. Only final assembly is needed and then gluing the back first to lock things in place. Must make sure that every bolts is tight. The engine will be mounted in the finished plane just as tight so you don't want any surprises

RE: DERIVATIVE, New 2X2
 

Niiiiice work!

Yeah, I already used that trick a couple of times in the e-birds.;)

Sorry if I missed it earlier or didn't see it in the photos, but are you using a nose ring with the DLE?

RE: DERIVATIVE, New 2X2
 

Thank you Bob.

The DLE doesn't look all that big inside there, does it? The chin cowl is deep enough to give me 1" clearance on the plug wire. I suspect that this combination will not be out of place.

I will finish the engine, nose ring and pipe installation before doing anything else. Stay tooned

RE: DERIVATIVE, New 2X2
 

I haven't seen the chin cowl, but it looks like not a lot will be sticking out... maybe the spark plug cap and wire.

The engine doesn't look out of place at all. The current 'widebody' trend works well for it.

If you keep this up, I may go back to gas.:D

RE: DERIVATIVE, New 2X2
 

Hello Matt

Great job.
Which DLE is it ?
How engine is fixed in front of. Is there a ring as for example shown on this picture ?

Claude

RE: DERIVATIVE, New 2X2
 

Thank you!.
It's the 55cc. I've done the development work with this engine on an EF Extra. As you can see the engine case has been put on a diet taking about 130 grams out of the engine. My particular copy of the DLE55 has worked absolutely great. I hear a lot of good about this and other DLE engines and a few bad points here and there; mostly good tho.

When I was modifying the engine over the summer, I cut a new key slot for the drive key and repositioned the pick-up at 180 degrees. It required moving 45 degrees from factory setting. This facilitates the use of a nose ring. I haven't made the ring yet but that's trivial.... an hour's work. I'll show how that will go together as I finish that work, possibly over the weekend.

BTW- the piped DLE puts out more than 6HP, turning a 22x12 2 blade or a 20x12 3 blade. My favorite is the 20x12 3 blade but isn't quite enough prop for the available power. I have a modified 3 blader, 20 3/4 x 12 that should work great too. However, for anyone wishing to tackle this project, the 20x12 3 blade Mezjlik works exceptionally well. I discussed the virtues earlier in the thread. Thrust like no other in this size, exceptionally quiet and superior brakes on downlines with superb throttle response. What else is there?

It's a YS 170 on steroids for 2/3rds the cost. The big difference is you have to make most everything yourself where the YS has practically every supporting piece of equipment available for a price

RE: DERIVATIVE, New 2X2
 

The nose ring build with its mount....

Damned server just won't accept my snaps

RE: DERIVATIVE, New 2X2
 

Let's try again.....Just not working 2nite. Try again 2morrow nite

A brief description:

Ring is 2 layers of 1/32" aircraft ply, laid up with 3 layers of 2.5 oz glass cloth bias cut. Ring weight is 2 1/2 grams and soft tubing is another 2 grams. The mount is 3 layers of 1/32" aircraft ply and no glass. The whole assembly including epoxy weighs less than 10 grams excluding the bolts which are 4-40's and blind nuts.

All layers are glued together with ca....simple, effective

RE: DERIVATIVE, New 2X2
 

I keep getting a 500 - Internal server error

Anyone else have trouble downloading photos?

RE: DERIVATIVE, New 2X2
 

Finally....some of the photos have been successfully uploaded

I changed the type of rubber I use as the bumper around the ring. The black rubber, neoprene, more than doubled the weight of the ring. I changed it to polyurethane and shaved a bunch of weight off. The whole assembly, ring, rubber bumper, fuse mount and epoxy added about 1/3 ounce.

RE: DERIVATIVE, New 2X2
 

I had to make a flexible driver to enable working with certain bolts on the mount. The mount is large as can be seen in the photos, and the angle to some of the bolts less than ideal. This simple flex tool makes the problem disappear.

Made from a length of boat drive shaft I had laying around

RE: DERIVATIVE, New 2X2
 

Fitting and securing the canopy.

The grooves are milled oversize and then are filled with microballoons for a perfect match. If one wasn't as fussy as I am about fit, he would stop after this level of fit was done. It's how the factory fitted the fuse and canopy; but there is 1/4 mm of space all around the canopy perimeter that should be filled for a perfect fit.

The plastic sleeves on the front locating pins are necessary to avoid scorching from vibration. This isn't an electric so one has to be concerned with these things.... Outer nyrod stock is perfect for this as the pin dowels are turned to a perfect fit. A piece of teflon sticky back tape keeps things separate when gluing the sleeves in place

RE: DERIVATIVE, New 2X2
 

The get a perfect fit, I wax the canopy flange with Part all and run a bead of microballons all around on the fuse.

The blind nut has a piece of fiberglass over it to keep it from coming loose. How many times has the nut come loose and rattle in your fuse? Ruins your whole day

RE: DERIVATIVE, New 2X2
 

Matt,

Simply amazing things you are doing here. Looks very solid and light at the same time. Not without a lot of effort and thought on your part, for sure. Bravo!