DR-1 (Sands): Builders Group - Page 152

Jim Bruton · 28 August 2006, 04:43 PM

Dogtail2,

After the inner most rib positions (yes, leaning, though almost twisting), I did keep the Sands other rib positions. If I haven't already, I can pass along those inboard rib positions to anyone who wants them- center and lower wings: lower for the landing gear clearance and the center for the cabanes- the sheet metal will fit better as a result, and I will have details on that when the time rolls around.

You are right, the elev/stab are big indeed! Yours look great!

Jim

Charles Neely · 29 August 2006, 10:27 AM

Mr. Burton and all Forumites (love the thread!!!)

I don't know what problems you had covering your test rudder with Poly-Fibre, however it reminded me of a tip that I learned a few years back that produces amazingly smooth results at wing tips and surface outlines.

If one uses the factory procedures booklet, you will want to forget the iron (at this stage) taking up the pucker (excess) cloth at a rounded tip. There is a better/easier way!

Basically, lay the cloth on the surface and trim roughly 6" outside the curved tip (not actually needed, but I found it better). Instead of using iron to take up that excess, attach large plastic hand operated spring clamps about every 6"-10" around the cloth edge and let them hang (slight weight of the clamps is important). Now start gently tugging on individual clamps in a side to side (angular) downward movement. The pucker will dissappear, resulting in a completely smooth fabric surface and tip application ready for edge gluing. You will also find the fabric has formed itself more than 1/2 way around the tubing edge. I preglue the tubing and wick thru with MEK to adeare the fabric. Then trim and seal the edge with iron before proceding. There should be no wrinkles at this stage. It is my understanding that this basic procedure will also work with cotton fabric, too. AFAIK, his method was developed by Ty Sundstrom of Dawn Patrol Aviation.
Keep up the amazing effort!
Charles Neely

Jim Bruton · 29 August 2006, 12:10 PM

Thanks Charles!

I'll have to try your method- does sound easier than trying to move that iron around curved and thin tubing.

Contribute more tips and thoughts anytime!

All the Best,

Jim Bruton

gipsymoth236k · 29 August 2006, 01:29 PM

I know that you can get outside reinforcing tape fabric to curve around outside perimeter tubing nicely with resulting compound curves by first tightly rolling the taped fabric over the ball end of a ball-peen hammer.

I hope this helps somewhere in your fabric work!

Regards, Gary Sewall

Makhpiyaluta · 29 August 2006, 01:57 PM

Quote:

Originally Posted by gipsymoth236k

I know that you can get outside reinforcing tape fabric to curve around outside perimeter tubing nicely with resulting compound curves by first tightly rolling the taped fabric over the ball end of a ball-peen hammer.

I hope this helps somewhere in your fabric work!

Regards, Gary Sewall

Correct this tape has the threads diagonal instead of horizontal and vertical. It works perfect.

Willem

greatwarpilot · 29 August 2006, 04:43 PM

If you're looking for it they usually refer to such tapes as "Biased" and they work like a charm. Thats what we used on the wing tips, rudder and basically all outside curves on the Triplane in the "Flying DR-1 Rebuild" thread.

Jim - No I haven't been up in it lately. Most of our airshows were earlier in the summer. Plus I've been away on a glider towing contract for the last 6 weeks. The only old airplane I've had a chance to fly recently is the T-6 (wrong war... I know. You take what you can get right?).

However this seems like a good opportunity to mention that the Great War Flying Museum will be hosting its annual Open House in a few weeks (Sunday September 10th to be exact). For anyone in the area this is a good chance to see our whole fleet fly. In addition its attended by WWI re-enactors and is generally a good time all round.

Cheers

Edward

Jim Bruton · 6 September 2006, 06:33 AM

This is from Ron Sands Jr., not me! (Thanks Rex for forwarding this to us!)

Sands Fokker DR-1 Triplane Replica Drawing Updates

Please make the following changes to your Fokker DR-1 Trip1ane Replica Drawings

(Note – Some of these changes may already be in your drawings)
Sheet #1-Plywood sheet "D" -change lower portion of sheet(7-5/8" x 50") to show 45 degree diagonal cuts for spar web scarf reinforcements-cut strips @ 2-1/2" wide as required.

Sheet #3-Face grain of inner and outer spar webs has been changed to 1/16"-45 degree face grain 3-ply aircraft birch plywood. Position face grain at spar
centerline to be an inverted V. Add note to rein. plate detail: Face grain of rein. plate is same as web or plate. Add note: 45 degree scarf joints parallel to the 45 degree face grain are best for spar webs. Add note: For Aerobatic use, it is recommended to use 1/8"-45 degree face grain 5 ply birch aircraft plywood for both inner and outer webs.

Sheet #4-Relocate 1/4" dia. drain holes in vertical webs ONLY from inboard side of rib location to outboard side. This position optimizes drain hole location
in reference to the 45 degree face grain direction of the plywood vertical webs. The 1/4"dia. drain holes in the bottom web remain at the same location.
Change the flange spacer from 3/16" thick plywood to 5/8" thick sitka spruce
with the grain of the piece running vertical. Change spar spacer from 3/16" thick plywood to 1/4" plywood and gusset the side and top and bottom edges of the spacer with 3/8" triangular spruce gussets.

Sheet #6-Add note that all wingtip gussets are 1/4"-45 degree spruce gussets. At rear trailing edge 1/2' square spruce rib spacer, add note that the 4 gussets are 1" triangular x 1/2" thick spruce.

Sheet #9-Add note: Alternate method of hub construction: make weldment using 2-1/4" 0.D. x 1-1/2" I.D. x 5" long #4130 tubing (2 req.); 5" dia. x 5/16" thick #4130 plate (4 req.). Machine bores and faces after welding.

Sheet #10-Has been redrawn to include a half-size detailed isometric view of a steerable tailwheel and spring installation with all brackets, hardware and 6" X 2" wheel assembly, and steerable rudder control arm. A new sheet #10 is available for $10.00 postpaid.

Sheet #11-Add note to glue fabric attach wood blocks to metal tube spar with epoxy glue.

Sheet #12-The 4 triangular gussets as newly noted on sheet #6 have been drawn in at each inward full length rib location with note- l" triangular spruce gussets- 1/2" thick.

Sheet #13-Same as Sheet #12 and add note to cover end of most inboard rib with fabric.

Sheet #14-Same as Sheet #13.

Sheet #17-Fuselage side view has been redrawn to change position of top longeron at STA.132.68. The top longeron should be at 16" from vertical centerline from STA."0" to STA.132.68. The correct dimension at STA.132.68 to the top of the stabi1izer support longeron is 1-7/8". Add note: For Aerobatic use, it is recommended to use .049" wall tubing instead of .035" wall for the 7/8” dia. & ¾” dia. tubes.

Sheet #22-Add note at rotary engine cowl face lower cylinder opening - Opening is 12" wide x 35" long with 6" radius at corners.

Charles Neely · 7 September 2006, 01:53 PM

Jim, everyone,

Please excuse me but I just had to crow a bit. Mike Gretz just informed us that a Piper Super Cub we (Dawn Patrol Aviation) restored had won best classic Pre-1956 at Blakesburg IA, AAA fly in. Owned by David Mars, it is the covering job we learned the wrinkle free iron-less tip trick on. With a motor breathed on by Ly-Con and micro-aerodynamics VG's, she cruises at 120! And is rock solid on the controls in all ranges. 'Bout the FUNNEST Cub I've ever flown!

charlie

Jim Bruton · 8 September 2006, 02:59 AM

..You'd better be careful, or we are going to send you a plane ticket and bribe you with beers to cover our aircraft. That's great news Charlie, congrats to you and your friends!

Jim

Jim Bruton · 8 September 2006, 03:03 AM

Calling all DR-1 builders or owners!

Look at Sheet #12, upper wing. look at where the upper part of the cabane strut attaches to the front spar bracket. See that attach bolt, with its head up and threads down? OK, when the wing is covered, please tell me how you will access that bolt to remove it or insert it. I do not see an inspection plate referenced in that area, and can't see a way for my fingers to wiggle over/under the spar to get to it.

Obviously, this isn't a problem for anyone who owns and transports a disassembled DR-1 to shows like Dayton.

Thanks!

Jim