ptulmer

My Feedback: (5)

It was too long in coming! I've wanted to do a reedie twin for a long time. Here's a peek at the drawing. My website is thoroughly goofed up at the moment, so it won't be posted anytime soon. If you're interested, let me know by PM. This could easily be retrofitted to an existing wing, which is what I plan on doing.

KidEpoxy

OUTSTANDING!

Any ballpark ideas on how much Outward thrust angle for when one quits?
I remember one guy (Ed?) runs some birds with a ton, like 8deg ... which looks kinds silly up close.

I cant really tell from the posted pic, will a Fuji tank fit in the nacelle?
Did you have a specific tank in mind?

And lastly, would you recomend any beefing the spars if we extend the wing 1 Bay each side for some more sqaures for the added weight & speed/Gs?

ptulmer

My Feedback: (5)

Kid, you could wait until mine is test flown and see 'fer sure, but I doubt it will need much if any as long as SS's are used. To tell the truth, I'd kiss the fella that could get me a counter pitch 5x3 Cox prop so I could run the engines in opposing directions! But just in case, I'm fitting some SS's with throttle sleeves. I was going to use an aluminum ball with a hole in it down the choke tube to simply cut throttle, but changed my mind after having some Brit go "phfffft" in my ear when I said that.

The tank I used for dimensions is the 1oz Sullivan slant tank. A fuji would fit, I'm sure.

Extending the wing wouldn't be necessary, but would add some cargo capacity. If you do extend it, use a basswood or spruce spar. (not balsa!) A spruce spar the size of the DNU's works all the way up to a .15 size airplane.

KidEpoxy

I hear ya on the Pusher Prop,
the 3blade is a 5x3 and the 3blade pusher is 5x3.5
like they are just trying to make things difficult.

maybe that would work, but the twin sound would sure warble like StevieNicks on PCP

skaliwag

My Feedback: (1)

PT... I was going to tell ya I had one but then I read the Kussing part.

ptulmer

My Feedback: (5)

Don't worry Steve, the airline tickets have gone up too much (triple!). I would have given you the kiss at Hops and Props. Which two props would match up? I've got the three blade pusher, but not a two blade. (nor a three blade tractor...)

injunnut1

The Grish 5.5 x 3 tractor and pusher props work well on Cox twin engine projects. Also you might try the Cox 6 x 2 black pusher prop along with the Cox 6 x 3 black tractor ...... the 6 x 2 prop is the one as used on the RTF Cox PT-19 Ukie models. The Cox 6 x 3 tractor prop is actually much closer to 2" in pitch if you put it on a pitch gauge, as is the case on almost ALL of the (underpitched) Cox props. Technically the black 6 x 2 prop used on the Cox PT-19 model is actually a 'left-hand tractor' prop, but most people simply call it a pusher prop ..... same goes for the Grish 'pusher' props, it all has to do with the prop's 'hub design'.

BMatthews

Somehow the thought of two Sure Starts on a 32 inch model fills me with fear and trepidation....

Ya know what would be sort of cool? A DNU twin version sort of modelled on the old Grumman Skyrocket. Longer nacelles for balance and cut the nose short and pop on a canopy.

Or a sort of DNU twin Mosquito where the nose is about as long as the nacelles?

Or who will be first to put a twin engine wing onto a regular fuselage and have a DNU trimotor?

ptulmer

My Feedback: (5)

You've been hanging around Ray, haven't you.[&:] Since there is a spare wing in my stash and a flying airframe in my hangar, this does seem like a likely thing to happen!

hogflyer

I've got some modification drawing someplace for a twin mod for the Midwest Sweet Stik (this was after the Sweet Stik and Twin Stik had been discontinued). I measured the distance from the CG to the firewall then designed the new nacelles to be 1/2 the distance to the original firewall minus 1/2" to compensate for the added weight of the nacelles themselves and the fuel tanks. Right nacelle has 8 deg. right thrust, the left has 4 deg. left thrust. Never did get around to building it - was going to be twin .40 powered. I also designed the nacelle sides to combine a full size rib so it had the strength of the full wing chord to support it, but it shouldn't be necessary with the DNU, but spruce, basswood or pins spars should be used like PTU said.

Can't wait until it's finished and flying. Lets see lots of build pictures while your at it.

Hogflyer

ptulmer

My Feedback: (5)

Shot of the wing with nacelles dry fit. All I gotta do is make the short ribs and install them, then it's time to cover!