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Posted by Old_Pilot | Jan 14, 2022 @ 05:56 PM | 15,328 Views
Down to push rods and control horns......and I may have a way to disguise those ugly #64 rubber bands.....more tomorrow

Well, that didn't work..I tried to "dye" the rubber bands with a dark red, alcohol based permanent ink......unfortunately the ink attacks the rubber and when stretched you can start to see a bit of surface fraying, plus the color loses it's intensity as you stretch the rubber band...but hey, for $2 worth of ink, it was worth a shot.....so I bought some red #64's from Amazon
Posted by Old_Pilot | Jan 13, 2022 @ 01:59 PM | 24,957 Views
6 hours later, I got the bottom of the wing covered.....the transparent covering is even easier to deal with than the opaque....guess I'll do the top tomorrow
Posted by Old_Pilot | Jan 12, 2022 @ 02:43 PM | 30,736 Views
I'm very pleased with the new covering material. Good adhesion, shrinks tight, and you can work the corners without having to cut facets. But I noticed that some of the seams were showing a bit of the adhesive (it's white)......until I wiped it down with acetone.....The best part about this stuff is it's price....MonoKote is basically $4/ft......this stuff is $1/ft, and you get a 16 ft roll for less than a 6 ft roll of MonoKote.

I'll cover the wing tomorrow
Posted by Old_Pilot | Jan 11, 2022 @ 09:14 AM | 29,307 Views
Gonna start covering today.....transparent red for the wings and stab...bright yellow for the fuse and fin....yellow orientation stripes....black trim and decals.......trying a new covering material...Neucover....1/4 the cost of MonoKote..

https://www.valuehobby.com/accessories/covering.html

Agree with keeping the rudder....DUG Mk-1 proved that
Posted by Old_Pilot | Jan 09, 2022 @ 04:27 PM | 32,117 Views
I got the wings joined and the aileron servos mounted, as you can see......had to put her on the scale,,.all the balsa, (4) servos, and the ESC weigh in at 24.5 oz. The motor prop, and battery weigh in at 10.30 oz..the covering and push rods will add another 3 oz, so projected AUW will be 37.8 oz....that yields a wing loading of 37.8oz/4.07 sq ft = 9.28 oz/sq ft........not as light as I wanted, but better than DUG MK-I
Posted by Old_Pilot | Jan 09, 2022 @ 02:18 PM | 30,659 Views
I hope I'm not being too sentimental (or just mental), but while I was waiting for some epoxy to set, I was reminiscing about my career and then retirement. I went from designing and building large industrial process facilities all over the world to....balsa and foam aircraft in my shop in the back yard. Some might consider that culture shock too much to handle....But I've found that I enjoy the design challenges and get just as much joy from scratch building an air frame.....especially when she noses up on her own for the first time and takes flight...The experience is even more special when I can share my madness with you guys !

I especially want to thank Bmatthews and lincoln for their input, guidance, and answering my silly questions....

Keep your nose up in the turns
Posted by Old_Pilot | Jan 08, 2022 @ 03:29 PM | 28,767 Views
Got the outboard panels of the wing built an rough sanded...still have a bit of banjo work to do before I join them, but we're getting there. Aileron hinges are a thin nylon fabric sandwiched between the top and bottom slats of the TE and aileron plates......invisible.
Posted by Old_Pilot | Jan 07, 2022 @ 02:07 PM | 25,701 Views
So, the center section of the wing is finished....except for finish sanding....I like the thicker trailing edge.....I also like the main spar..two pieces of 1/8" lite ply sandwiched together and continuous across the span........That's a 20lb chunk of lead at mid span....no deflection...I'll start the outboard sections of the wing this weekend..supposed to be wet and cold.......
Posted by Old_Pilot | Jan 07, 2022 @ 09:56 AM | 24,931 Views
Well POOP ! I made a mistake......I cut the end of the ribs at 1/4" vertical...for an eighth inch trailing edge....not sure what I was thinking. Apparently I wasn't....easy fix though...I'll just cut a second set of trailing edges and ailerons (they are all on one sheet together) and laminate them on top of the originals.....the upside to this (there's always an upside for me) is that those 1/8" TE's and ailerons were awfully flimsy......I doubt it will make any difference to the wing loading....And as an afterthought, I have the opportunity to laminate fabric hinges......HMMM !
Posted by Old_Pilot | Jan 06, 2022 @ 09:54 AM | 36,761 Views
Got the fuselage all but assembled, elevator and rudder servos mounted, battery tray and strap, and the push rod guides...dry fit the feathers.........Tab A into Slot B makes it go quickly
Posted by Old_Pilot | Jan 05, 2022 @ 09:16 AM | 49,038 Views
Got the feathers assembled, but when I put the small flat ribs in place, they just didn't look right..so I compromised and put some wider ribs in, some 1/8" diagonals, and smaller corner gussets......... even with all that, it will weigh less than the 3/16" original stab and fin
Posted by Old_Pilot | Jan 04, 2022 @ 06:06 PM | 53,104 Views
Wow, got all the pieces separated, de-tabbed, de-furred, and collected into the groups......in the meantime, my supervisors showed up after a long vacation......
Posted by Old_Pilot | Jan 03, 2022 @ 07:05 AM | 53,364 Views
Got all the parts cut yesterday plus some extras...I even cut all the 1/8" sq secondary spars and 1/8x1/2 outboard spar caps.....I'll separate and sand today. Total cut time was a little less than 6 hours....I was cutting slow (40 in/min) and shallow (0.032" per pass) with a 1/16" single flute up-cut bit

I know I've said this before, but there is no way I could cut this by hand with the accuracy and precision of the router.....especially since I can nest parts and reduce the waste.
Posted by Old_Pilot | Jan 02, 2022 @ 08:24 AM | 39,919 Views
One of my favorite parts of building......I should have all the parts cut this morning
Posted by Old_Pilot | Dec 27, 2021 @ 10:15 AM | 21,800 Views
I changed out that old (read "crashed) 2217-07 1250 kV Suppo motor and 8x4 folding prop on the 64" DUG to the new (read "un-crashed") GForce 2830-1100 kV motor with a 9x5 folding prop. The old motor had a grinding noise...could be dirt, or a bearing, or a magnet becoming loose.....the new folding prop folds better and the pivots are just a touch wider than the firewall.....We'll see, once the wind drops to 5-10......We're supposed to have wind and rain off and on for the next few days..but I've got plenty to do.

I'd flown the Suppo motor in several combat wedges.

I'll use the GForce 2830 - 1100 kV with a 9x5 prop on Das Ugly Glider - 76" - Mark II with a 2200 mah 40C 3S and 40 amp ESC
Posted by Old_Pilot | Dec 25, 2021 @ 10:37 AM | 9,635 Views
Had to modify both, but they both will work

The one on the right is a 2217-07 - 1250 kV

Wire Winds / Turns: 12
Li-Po Battery: 2 / 4 cells
RPM per volt: 1250
Max efficiency: 80%
Max efficiency current: 10 - 27A (>75%)
No Load Current / 10V: 1.6A
Max Watts 250W
Max Current: 30A / 60 sec
Dimension: 27.5 x 30mm
Shaft 4.00mm
Weight: 70g
Recommended ESC: Grayson Hobby 30Amp
Recommended Model Weight: 15-45oz
Recommended Prop: 8 x 4 or 9 x 5 with throttle management (3S - 11.1V)

The one on the left is a GForce 2830-1100kV

Specifications:

KV: 1100
Max Current: 26A
Load Current: 22A
Shaft Diameter: 4mm
Weight: 72g
Motor Diameter: 28mm
Length: 30mm
Designed for use with 3S LiPO with up to 12 x 6 electric prop.
Posted by Old_Pilot | Dec 22, 2021 @ 08:07 AM | 11,240 Views
To all my friends and colleagues here on RC Groups ....I hope you all have a safe, healthy, and happy holiday season. Merry Christmas and Happy New Year
Posted by Old_Pilot | Dec 19, 2021 @ 10:47 AM | 12,857 Views
I finished revising the drawings this morning, and I think they're correct. But since I'm the only one that will use them to build the model this time, I haven't annotated them. If she flies like I hope she will, I'll annotate them and publish again....but in a nutshell, all the wing ribs are 3/32" and the rest (fuse and feathers) is 1/8"...I have to make the outboard wing spars (1/8x1/2 balsa) and all the secondary stringers (1/8" sq)... Center section spar caps are 1/8x1/2 bass with a 1/4 ply continuous spar web. Wing joiners are 1/4 ply.

That pretty much covers it.....Here's what I'll cut and build from:
Posted by Old_Pilot | Dec 18, 2021 @ 05:20 PM | 10,592 Views
I couldn't make the PW-51 airfoil work with the servos I normally use (I keep at least 10 on hand), so I decided to take the advice offered by both BMatthews and Lincoln, that is, to build a high aspect ratio wing (9.94) using a 9-10% flat bottom airfoil (S7055) and reducing the wing loading to as close to 8.0 oz/sq ft as I can. To that end, I've reduced the thicknesses of everything practical, increased the wing span by 12", increased the rib spacing but added 1/2 ribs in between, and changed the airfoil, all in an attempt to build more of a floater than a warmliner.

It took me 2 days to make those changes on the drawings, but I'm reminded of an old saying from my days as an engineer...."It costs a dollar to change the drawings, 10 dollars to change it in the shop, and 100 dollars to change it in the field."

I guess we'll see