Progress! Expo handle update.

[Larry Renger]

I have parts on order to make up 50 new kits!  It will be at least a month before the parts show up, so don't get your wallets out quite yet. 

Keep an eye out for reviews from the modelers who have built an used the last batch of kits. There are 25 of them out there. Jim Hoffman just built two, and has one of the older types in use also. They seem to be addictive. 

[john e. holliday]

Hey Larry, the old DOC finally tried the handle today.  I took my King Sweep out to dust it off.  First flight it was sluggish on out sides and barely okay on insides.  Did not try full pattern as that's how bad it was.  So I said, "Self it is time to try the new handle".   Boy I'm glad I did as the maneuvers to me  were nice and crisp with really smooth level laps.   The plane went where I wanted it to go for a change.  So keep the old DOC on the chart for another handle.

If pictures load you can see the two handles I played with.  Thanks again.

[Larry Renger]

There are two things going here. First is the exponential rate of control with handle deflection. The second factor is the fact that the effective line attachment point is half way between the line clip hole and linkage pivot point. That puts it just about at the inside of your fingers! I don't know of any other handle with so little overhang.

The result is that the torque required to deflect the handle is much reduced, making the plane feel more responsive. Kind of like power steering.

Just watch out if you switch back to a conventional handle, the model won't be going where you now expect it to!

[john e. holliday]

Well I have one plane that has used almost every handle I have and I keep going back to the old Hot Rock style with.  Need to try the new handle on it. 

[Larry Renger]

I have an Exponential Hot Rock! Want to try it?

[john e. holliday]

I'll pass.

[Target]

I'll try it!
Bring it with to WN next Friday, June 16th; I hope to be out of work jail by then.

[Jim Hoffman]

I recently had the opportunity to put three flights on my Snoopy stunter using Larry’s low overhang Expo handle.
The results were favorable. The handle gives a different feel and provides stunter with some welcome boost in some spots in the pattern. I will need more trim flights to dial things in, the set-up is promising and I plan to invest more time to refine the handle/airplane combo.

•   I notice (and like) the increase in the turning gain in the vertical eight during the outside loop when one is heading downhill towards the intersection. 

•   My Snoopy airplane flies a tight corner and can be susceptible to a missed heading when exiting the corner.  The Expo handle seems to help tame the corner; more trim flights needed to fully address this characteristic.

•   I was able to reduce the Expo handle spacing to a narrower spacing than I’d been flying w/ the original hard point.
The model is a 50 oz., 585 sq. inch wing, PA 40 light.  5.3 laps on 65’ lines (.015 braided cable).  Next experiments will include shorter lines and some nose weight.

Jim Hoffman

[Larry Renger]

Chris flew with both the Expo Hot Rock and current Low Overhang version as kitted. His plane survived both flights. He thinks the LO handle is better than the Hot Rock, but both would take some getting used to.

Perhaps he can be persuaded to pitch in with his own commentary. 

[Target]

Thanks for loaning me the handles today, Larry!
My impression is that the handles do in fact work, making level flight less sensitive.
It's pretty much like having a wide spaced handle when you get into a square corner, but a narrow spaced handle when flying level.
The best landing I've ever made on the Oriental was made today on Larry's handle. Coincidence? I think not!
R,
Chris

[Larry Renger]

Good news! I have the first installment of handle parts. Ten kits are available now. Ultimately I plan a run of 100 handles, so if you want one (or more!) they will be forthcoming.

[jfv]

As noted earlier, I'm in for one.

[John Rist]

Just ordered two.  Larry Renger responds very quickly to eMail and takes PayPal.  Looking forward to trying this new handle.

[John Rist]

Larry,  What size are the two screws that come in the kit?  The ones used to mount the two aluminum arms.  They are bigger than 4-40 screws.

[Larry Renger]

They are 5x40 by 5/8"

[Larry Renger]

First batch gone, but got in another care package of parts!  Get 'em while they are hot (laser cutters do burn the wood, after all). 

So far, the modifications I have heard of were adding mylar film or 1/64" ply spacers in the cavities for the links. The intention is to reduce side motion and friction.  The other change is to use 1/8" x 3/4" Hard Steel dowel pins instead of the 5x40 bolts. That should kill off any possible wear!

If you do these things and brass bush the line attachment hole, you should have a handle worthy of willing to your great grandkids.  Just keep termites away from it.

[Bill Ambrose]

Larry,

I would like to get one of those handle kits from you.

Bill Ambrose

[Larry Renger]

$30.75 via Paypal includes shipping. Pay to larry_renger@earthlink.net. Be sure to give me your address or I get money and you get nothing.

[Larry Renger]

OK! About 50 kits sent out! Don't let them moulder on the shelf. Build them, fly with them, and feed back how they work. 

I want to fine tune the design to suit the users, and can't do that in a vacuum. Don't be shy, negative input is usually more useful than positive! That is how it got as far as it has! 

[Ara Dedekian]

         Still glopping on the urethane, nothing to report.

         Shaping the handle to fit my hand was like fitting a denture; carving away the areas hitting the fleshy and bony parts of my hand making the grip quite comfortable.

         Ara

[John Rist]

         Still glopping on the urethane, nothing to report.

         Shaping the handle to fit my hand was like fitting a denture; carving away the areas hitting the fleshy and bony parts of my hand making the grip quite comfortable.

         Ara

Is it possible to grind in some bias in the hand grip?

[Larry Renger]

You would have to replace the wood parts with new ones, the handle is so hollowed out that you don't have enough wood to work with. Still, it isn't all that big a job to cut out a set of parts on a jig saw. That is how I made my original test models.

[Allan Perret]

So I built my two handles this week, will try them this weekend if weather cooperates.  I set one up at max spacing and other at min.  At the min spacing there not enough room for a comfortable grip at the top link.  When I hold the handle with my normal grip the upper link hits the first joint of my index finger.  I have to hold the handle in either a stronger or weaker position to have clearance for full travel of upper link, neither of those is comfortable for me.  I would be scared to fly my full size stunters with the weak position grip.  Will only feel safe with the stronger position, but don't like the idea of having to adjust my grip to accommodate the handle.  I feel like the U-links should have more spacing between the pivot point and the line connection point, maybe 3/8 ~ 1/2".

[Larry Renger]

So I built my two handles this week, will try them this weekend if weather cooperates.  I set one up at max spacing and other at min.  At the min spacing there not enough room for a comfortable grip at the top link.  When I hold the handle with my normal grip the upper link hits the first joint of my index finger.  I have to hold the handle in either a stronger or weaker position to have clearance for full travel of upper link, neither of those is comfortable for me.  I would be scared to fly my full size stunters with the weak position grip.  Will only feel safe with the stronger position, but don't like the idea of having to adjust my grip to accommodate the handle.  I feel like the U-links should have more spacing between the pivot point and the line connection point, maybe 3/8 ~ 1/2".

You could sand away more clearance for your fingers in the wood parts. There is some leeway there. (or put your fingers on a diet  )

[Allan Perret]

You could sand away more clearance for your fingers in the wood parts. There is some leeway there. (or put your fingers on a diet  )

Already did that, used up all the leeway .