RV-8 Bent Stick geometry

So I've searched the archives, and read all the threads on stick bending. I currently have two setups that I have tried.

First I have a shortened straight stick with a Tosten grip. Now this grip angles forward a bit so the grip is even farther away with the straight stick. Interesting this bend forward is very comfortable with your wrist angle. This is how I initially setup and flew my first 40 hours. While a bit of a reach in cruise to keep your arm and shoulder forward to hold the stick, it was fantastic in maneuvering flight and aerobatics.

So I got a bent stick and new grip. The Tosten won't work with the bent stick as you have to cut off too much to make the height work out with the panel. Once you've cut it there's no room for the insert that holds the Tosten grip in place. So I switched to the wood grip that Vans sells with the bent stick. The location is very comfortable and clears in all 4 corners of the range of motion. So far so good. The end of the stick is vertical just like the normal stick which I noticed is not as comfortable as the forward bend of the Tosten.

Well, after flying a few flights with the bent stick, while it's comfortable in straight and level, It is seriously compromising my ability to pull G's on the stick. I think it's the fact that my arm is now 90deg to the stick when moderate up elevator is being pulled. This geometry means that you are twisting your shoulder to move the stick back instead of pulling in a more direct angle. I felt a similar thing when landing 3 point where it was hard to pull the stick back enough to get to the stall.

So, am I crazy? is my arm weak? Will it get better over time? or is this the some people like it some people don't part about the bent stick?

Timely question Andy. I just put a bent stick, actually, cut and welded, that moves my Infinity grip back about an inch and a quarter. Went out and did some acro and noticed what you are saying. With the stick far back, my arm is rotating my shoulder instead of pulling straight back. Only flew for a short while doing acro, but did notice that's it's easier to fly inverted because the stick is closer and easier to push when inverted.




Like you say, much more comfortable flying straight and level.

I'll report back after this weekend. We have a show in Pensacola and I'll get a good workout.

Rather then ditch the grip how about bending your own? I decided to try the bend myself since the guy on the forum isn't doing it anymore. I think my bend came out well.

Blain said:

Rather then ditch the grip how about bending your own? I decided to try the bend myself since the guy on the forum isn't doing it anymore. I think my bend came out well.

Click to expand...

So what did you use to bend it? Tubing bender of some sort? Foot on the pipe? Super human strength?

Packed dry sand #60 or #80, can't remember, into tube. Capped the open end with wood plug, drilled for cotter pin, then used a hydraulic pipe bender. I didn't have a die the exact size so I built up the next larger size with titanimum epoxy. Still got wrinkles on the inside of bend but it doesn't seem to be a structural strength issue. Just an esthetic one. I'm built lower to the ground then most so I knew I needed to get that stick closer.

Impressive, You're quite handy Blain. I got mine bent with money and it has the same wrinkles you have. Like you say, not a structural issue, and if you cut and welded there would be a seam as well.

But my question still stands to others that are flying the bent stick, does the geometry work for you?

akarmy said:

Impressive, You're quite handy Blain. I got mine bent with money and it has the same wrinkles you have. Like you say, not a structural issue, and if you cut and welded there would be a seam as well.

But my question still stands to others that are flying the bent stick, does the geometry work for you?

Click to expand...

I just pulled my stick to install the Infinity grip, and I am interested about who/where you got the stick bent? I am also redoing the panel, and part of the plan is to remove an inch from the bottom to give more clearance for the stick (and my legs.). As for the cutting and welding method, I don't mind that "look" so that's an option as well.

CA

Andy---with the thin wall thickness and a fairly large OD tube, the tube is stretching on the outside, and wrinkling on the inside bends. A proper bender with a proper mandrel will solve that issue.
Problem is the benders and the mandrels are expensive machines. We are not talking about conduit benders here. Also--if you try to bend too tight a radius, it will do the same thing. A larger bend my work, but it will be a trial and error thing.

I'm going to have to do the same thing with the stick (s) in my 7, because of my short legs and arms (along with some other mods!). I'll let you know when I figure out!
Tom

The bent stick does work for me

I never flew my RV without a bent stick, so I don't know the difference. I just started doing a few aerobatics in my 8, and I like the bent stick, works fine.

TS Flightlines said:

Andy---with the thin wall thickness and a fairly large OD tube, the tube is stretching on the outside, and wrinkling on the inside bends. A proper bender with a proper mandrel will solve that issue.
Problem is the benders and the mandrels are expensive machines. We are not talking about conduit benders here. Also--if you try to bend too tight a radius, it will do the same thing. A larger bend my work, but it will be a trial and error thing.

I'm going to have to do the same thing with the stick (s) in my 7, because of my short legs and arms (along with some other mods!). I'll let you know when I figure out!
Tom

Click to expand...

Is it possible to use a mandrel with the pivot tube welded in place?

"probably" so, since you're bending above the pivot.
Gee---wish we had the dies to fit the tube---HUM-----
Tom

bent stick & Tosten grip

I made my own bent stick out of stainless steel. I first bent the 316 seamless, stainless steel tubing with two bends . I got a few wrinkles on the inside radius but not too bad . I have a homemade bender with dies for 1 in. od tube. Then tig welded in a pivot tube, clevis, and a cupped washer on the wire outlet hole for a doubler.Then welded a custom receiver that is "tilted" forward to position the Tosten grip in the correct attitude. The custom receiver has three set screws to lock the grip into position ( in case one or two come loose ) Then positioned a dowel pin in the pivot bushing and clamped the dowel in a large vice and bolted a fixed block in push rod clevis. Using a large fish scale we load tested it in all directions for deflection and bending. I don't remember the load but I used 2X the number that I found on this sight some where. I'm not sure but I think it was something like 80 lbs. that we pulled on it in all directions.
I would think one could tig weld a custom receiver end in a stock bent stick and make the Tosten grip work just fine. I have about 3/8 in clearance between cooley switch and bottom of panel and can loosen the set screws and rotate the grip to what feels good.Moved it once after initial flight. Ron

I know this is an old thread, but are there any commercial sources for the bent sticks? I notice a HUGE difference in comfort between the bent stick (good) and the straight stick (not great).

see here https://vansairforce.net/community/showthread.php?t=209397

I bought front and rear