Author Topic: Hardpoint Exponential Handle (Read 4416 times)

Larry Renger · « **on:** July 26, 2012, 12:11:41 PM »

RSM has been making my exponential handle for some years. It has proven popular, especially the 1/2A size. The drawback to the design has been that it is a cable type handle.

I have wanted to make it hardpoint, and tried a few designs. I finally came up with this idea. Simple and effective!

Don't know why I took so long and went down much more complex paths.

Anyway, a standard handle loses line spacing as you deflect it from neutral. This handle increases the line spacing as you deflect it, as you can see in the 2nd photo. So, you can use narrower spacing while still getting the kick you need for hard corners. Much smoother around neutral moderate in round maneuvers and lots of throw for corners.

Tim Wescott · « **Reply #1 on:** July 26, 2012, 12:48:40 PM »

Crazy people fly CL.

If you put the pivot points back in the hand piece, and kind of wrap them around the finger-hole, you can reduce overhang and get the same action.

In fact, you could make (effectively) variable overhang, but having a number of different arms of different lengths, and different pivot points in which to put them.

proparc · « **Reply #2 on:** July 26, 2012, 12:50:57 PM »

I have flown Larry's Expo handle, and it was marvelous. If this is an improvement, then it's got to be killer.

RogerGreene · « **Reply #3 on:** July 26, 2012, 01:49:41 PM »

I don't quite see how it works. Please explaine how it works.

Thanks.

Steve Helmick · « **Reply #4 on:** July 26, 2012, 01:58:37 PM »

Yes, please 'splain! It looks to me like the line spacing is narrow, then gets wider and biased relative to the CL of the grip. It's the bias that bothers me...

Steve

Tim Wescott · « **Reply #5 on:** July 26, 2012, 02:43:24 PM »

Quote from: RogerGreene on July 26, 2012, 01:49:41 PM

I don't quite see how it works. Please explaine how it works.

When you pull up the bottom line mount pivots while the top line mount hits a stop. So the spacing between the top & bottom lines increases.

Howard Rush · « **Reply #6 on:** July 26, 2012, 03:39:09 PM »

Quote from: Larry Renger on July 26, 2012, 12:11:41 PM

RSM has been making my exponential handle for some years. It has proven popular, especially the 1/2A size. The drawback to the design has been that it is a cable type handle.

I have wanted to make it hardpoint, and tried a few designs. I finally came up with this idea. Simple and effective!

Don't know why I took so long and went down much more complex paths.

Anyway, a standard handle loses line spacing as you deflect it from neutral. This handle increases the line spacing as you deflect it, as you can see in the 2nd photo. So, you can use narrower spacing while still getting the kick you need for hard corners. Much smoother around neutral moderate in round maneuvers and lots of throw for corners.

This looks like a dandy way of doing the "exponential" control. It's on the right side of the spring. Maybe you could make a sort of Dolby system with an Igor bellcrank and this handle.

De Hill · « **Reply #7 on:** July 26, 2012, 04:01:43 PM »

Hi Larry,

Where can I get one?

De Hill

L0U CRANE · « **Reply #8 on:** July 26, 2012, 05:59:28 PM »

Larry, EXCELLENT!

The function might have been easier to see if your first pic had the handle aligned with the cutting board grid at neutral. Then an image with the handle rotated to show how the stop acts on the 'down' line while the 'up' line remains free to aim at the model.

Thanks!

Larry Renger · « **Reply #9 on:** July 26, 2012, 11:38:28 PM »

I haven't heard from Eric whether he is interested in making these. I need to do some changes to the cut files to get the design finalized. I want to have more spacings available and also wider spacing for larger models. Plus laser accuracy in the hole positions. I will keep everyone posted.

The one shown is a modification of the .15 size "Renger" handle. You should easily be able to duplicate it if you buy the kit. It is made from good hard ply, not light-ply, so should easily handle (sorry about the pun) models up to .40

You do need varying length clips for line adjustments. Jim Lee makes a tool to turn them out.

Lou: you are correct and I realized it after posting the photos.

BTW the length of the arms controls the amount of expo action.

Dennis Adamisin · « **Reply #10 on:** July 27, 2012, 06:43:32 AM »

Nice idea. I have two more unfinished "15" handles that I could mod like this. BTW they are made of lite ply.

Do you have a guideline for how much expo action you get? If I was replacing a 3" normal handle with an expo, would I use say a 2.5" spacing with "X" length arms?

Larry Renger · « **Reply #11 on:** July 27, 2012, 07:58:56 AM »

Eric says that the stuff may be only 3-ply, but it is NOT lite-ply.

It isn't visible in the pictures, but there is a small chunk of ply glued in at the center to keep the outer panel spacing constant. The bolts are just snugged up. There is undesirable to squeeze the panels in. The arms are 1/4" deep 1/16" aluminum. I think I would go with 3/16" steel. That would allow the end hole to be closer to the outside. Another detail is to cut the center spacer down to 1/16" from the current 1/8". On the inner end, making a row of holes will allow you to adjust the expo intensity by shortening the arms.

As far as spacing, I would look at my usual handle deflection and make the line spacing somewhat less than what you would normally use.

Larry Renger · « **Reply #12 on:** July 29, 2012, 08:28:05 PM »

Well, I found out that I lost the files with the drawings of the handle!

Fortunately, Eric was able to provide me with his copies.

I have modified the drawing of the larger handle to my new concept. There will be 10 possible line spacings. However, NO line length adjustability or angle bias capability. For line length get the clip bender from Jim Lee, it works great! For bias, you can tweak the line lengths to be unequal as needed or adjust your pushrod lengths.

You will be able to bias the center of the lines up or down from the middle of the handle if you are using less than the maximum line spacing.

I expect that Eric will get me a set of parts in a few days and I can assemble it and do photo instructions within the week.

De Hill · « **Reply #13 on:** July 29, 2012, 08:33:24 PM »

Great!

De Hill

proparc · « **Reply #14 on:** July 29, 2012, 09:17:41 PM »

Larry probably assumes I forgot all about that flight with his expo handle and the 1/2A Magician down at Fountain Valley, CA flying field-I didn’t, (I never forget a flight). Because there has been so much arguing and fighting over recent tech developments, I feel I need to put a disclaimer here.

There could be elements in my reflexes and psysiology such that, Larry’s handle is particularly beneficial to me. I play blues guitar and in particular, I play a lot of up-tempo shuffles. For people here that are familiar with guitar, you’ll know that, that requires pretty well developed reflexes.

It is possible that there is just something in Larry handle that benefits me more because of this over-development. What I am trying to say is that for me, the thing was friggin amazing. But you may feel something different.

Larry Renger · « **Reply #15 on:** July 29, 2012, 09:30:50 PM »

Well I developed it because I have "Essential Familiar Tremor" which means my hands shake. Alot!! So having smooth flight at neutral, but killer control for squares is VERY important to me.

I will never forget when a judge said "your maneuver was very round except for all those corners". Hey ain't you seen a 32 point loop before? They be hard to do!

Heman Lee · « **Reply #16 on:** July 31, 2012, 09:59:31 AM »

Larry,
I need one of those instead of putting an circular bellcrank in my 1/2a Stunter.

Bill Little · « **Reply #17 on:** July 31, 2012, 10:09:04 AM »

HI Larry,

Is there any ideas about making your 1/2A handle into a hard point? How much difference would you expect in "feel" between your 1/2A cable expo handle and the hard point version?

Thanks
Bill

tom hampshire · « **Reply #18 on:** July 31, 2012, 12:50:46 PM »

Might it be good to change the stop blocks to allow a little, 10 degrees or so, of hand input before the stop causes the arm to give more gain to the line? So if you are flying level, or doing a round maneuver, there is no gain. Only for a square or triangle corner would the gain function kick in. Good, simple design in any case. Well done!

Larry Renger · « **Reply #19 on:** July 31, 2012, 06:34:32 PM »

I think that the .15 size handle will do for all applications. It has a very wide range of spacings available. As far as feel, I am not THAT good a flyer. You guys tell me.

As far as changing the function by moving the stop blocks, be my guest, try it and let us know how it works out.

I have been flying the full expo for years and like it just fine, as, it seems does everyone else flying my expo handles. But the more experimenters, the more we will learn.

John Stiles · « **Reply #20 on:** August 01, 2012, 07:27:17 AM »

Quote from: De Hill on July 26, 2012, 04:01:43 PM

Hi Larry,

Where can I get one?

De Hill

x2 that's a nice rig right there.....you gonna mass produce?

Marvin Denny · « **Reply #21 on:** August 01, 2012, 10:40:12 AM »

I would like a couple

Bigiron

Larry Renger · « **Reply #22 on:** August 01, 2012, 12:51:18 PM »

Me too!

John Stiles · « **Reply #23 on:** August 01, 2012, 02:15:21 PM »

Quote from: Larry Renger on August 01, 2012, 12:51:18 PM

Me too!

now get busy before I hafta.......send my mean ole'lady out there to whup ya!

Larry Renger · « **Reply #24 on:** August 01, 2012, 02:32:25 PM »

Waiting on Eric. His mission, should he choose to accept it, is to get me a set of the new parts so I can finalize the design and write the instructions.

proparc · « **Reply #25 on:** August 01, 2012, 03:41:37 PM »

Quote from: Larry Renger on August 01, 2012, 02:32:25 PM

Waiting on Eric. His mission, should he choose to accept it, is to get me a set of the new parts so I can finalize the design and write the instructions.

Soo!! Your plan is to farm out production, so in the event of a disaster, you can invoke "plausible deniability".

Larry Renger · « **Reply #26 on:** August 01, 2012, 04:01:24 PM »

I never produce anything, just designs. Eric kits my handle and model designs under his own RSMDistribution label. I think he plans to kit my Sky Streak flying wing too.

proparc · « **Reply #27 on:** August 01, 2012, 04:06:58 PM »

Quote from: Larry Renger on August 01, 2012, 04:01:24 PM

I know your a design Engineer. Do you also do Manufacturing Engineering?