Chad Veich

My Feedback: (60)

No doubt a properly engineered set with quality components is just as reliable, and probably more so. The problem seems to be that the quality and engineering is still lacking. Honestly, I've seen and read about more failures with electric gear than I have pneumatic in recent times. I have not doubt that electric retracts are the wave of the future, I'm just not ready to throw all my pneumatic stuff in the trash just yet. My .02 cents of course.

SrTelemaster150

Here is a picture of the Robart lineal "actuator" @ .875" extension. That's leaving about .225" of threads in the barrel.



Note that there is nothing to hold the threaded rod from rotating so a bellcrank must be used when the actuator is mounted remotely. I would not trust this connected directly to the pushrod as it would probably eventually lead to the pushrod un-screwwing from the clevices on the control horn.

When the actuator is mounted directly to the TW retract, the linkage keeps the threaded rod from rotating.

invertmast

My Feedback: (23)

Or you could just put a jam nut on the actuator threads to keep it from rotating...

SrTelemaster150

The clevis on the actuator threads isnn't the problem. There is a set screw locking the clevis on the actuator threaded rod. The problem would be the possibility of the torque from the actuator spinning the pushrod @ the retract linkage.

You might feel comfortable W/a locknut on the pushrod to keep things together, but for me, spending a little time fabricating a bellcrank would make me feel a lot better.

A bellcrank transition will make it impossible for torque to be tranmitted to the pushrod.

Flyfast1

My Feedback: (1)

So, have people been using electric retracts in large warbirds, say 30 lbs or heavier, on paved runways, and have they been holding up?

-Ed B.

Chris Nicastro

My Feedback: (3)

You guys want to blow a gasket go price BVM electric sport gear... That will add some perspective to the costs of gear lately... Insane imo.

SrTelemaster150

The Robart electrics work basically the same as the pneumatics. The linear actuator is substituted for an air cylinder. The have the same down-lock design as pnematics. There should be no difference in durability as far as the struts/linkages.

raptureboy

Just being in the hobby at this level is insanewhy couldn't I just be happy with my hobby store foamy electric or air they all have problems and cost lots of $$$$

toolmaker7341

Hal deBolt sold electric retracts in the early 60's @ $24.95 ea.

Flyfast1

My Feedback: (1)

I see. I didn't realize that structurally they were identical except for the actuator.

Thanks,

-Ed B.

Ramstein44

My Feedback: (157)

My major concern with electric retracts is the "wear and tear" aspect of them. How durable are the components in the long run and what about part replacement and cost.. I know with air systems, I can buy parts fairly easily and they’re proven to last many hard landings.

mikes68charger

My Feedback: (34)

Wow, I did not realize the prices were that close once you include the air kit etc. Now servos I don't ever count them in the cost as I have a ton laying around.

But I guess for my next gaint scale war bird will be electric.

I guess Im getting older and I like to use what works.

So as I have only been flying for around 2 years, what maintenance do air retracts require that electrics dont?

I don't want to have a issue down the road.

Thanks

wphilb

My Feedback: (10)

Can you just buy the linear actuators and the controller and then swap out the cylinders/actuators yourself? Robarts quote for upgrading them was more than I wanted to spend.

Whit

jblloyd

My Feedback: (17)

I recently install the Robart electric conversion kit for their #150 retracts on my TF giant scale P-40. Took about 15 minutes to change out the air cylinders for the electric motors. Althought the upgrade kit may seem to be a little pricy at $230, is was well worth it to me to be able to get away from all the worry about air pressure failures. Now I am confident that I am not going to lose a $1500 airplane because of an air leak.

http://www.youtube.com/watch?v=y1qTFmBXXLU

SrTelemaster150

Whats cool about the FW 190A W/E-retracts is that it is true to the full scale version.

The FW 190A used all electrics for retracts & control sufaces. No hydraulics.

larry@coyotenet

My Feedback: (21)

Durability is definitely the problem. I have extensively researched electric retracts for giant scale use, I have had a set of the Robart conversions in my hands, a set of Likes with years of use, and have looked at all sorts of miniature linear actuators which are adaptable for use in Robart or Sierra type retracts. Here are my conclusions.
1. The Likes work well and are durable, but they are big and heavy. They use simple micro switches and are pretty bullet proof.
2. The others all use some form of a miniature robot derived motor and gearbox. It is amazingly small and powerful, fits inside a Robart sized air cylinder and when teamed with a worm screw drive output shaft produces several hundred inch ozs. of torque. Cycle times are around 7 seconds. If you want to see one go to your search engine and type in "robot gear motors" and look at the Poloiu (pardon my spelling!) gearmotors. You can watch a linear actuator working by going to youtube and searching for Firgelli linear actuator.
The real cost of the electrics is in the control box and the programming.
The problems I have experienced,and which have lead me to go back to pneumatics at this time for heavy models, are related to the gearbox shearing teeth off the last output gear.
I am sure the electric retracts would be fine for planes under 80". The weight of scale wheels , wheel covers and struts put quite a strain on the gearbox and the trade off of slowing down the retract by increasing the gear ratio of the gearbox makes for unacceptably long retract and extension times. I am still looking at a way to convert my pneumatic gears to electric but at this time haven't seen a really good alternative.
I am a retired office equipment and computer guy and have lots of experience working with small mechanical devices with lots of gears and gearboxes!
Larry

Whistling Death

Well, I just ordered a set of Robart electric retracts for my Hanger 9 P-51, 150. Lets see how it goes.

electric eddie

How did they work out whistling death??

irocbsa

My Feedback: (12)

I think that most of us are having mixed results. You can get reliable electric gear but you will pay an arm and a leg for them. If you want some very detailed information about all of the choices, there's a thread a few pages back that will tell you more than you probably want to know.

A lot of us were hoping for an affordable (read less than $300) and reliable set of electric gear to come out but that has yet to happen. ESM's V3 electrics looked incredibly promising but their failure rate has been at an unsustainable point and they have decided to revert back to air units. It seems like every manufacturer out there almost gets it right, but we inevitably find out that one of the components come up short. Of course, that ends up making the gear a complete waste of money. The search continues...

Noticed you're from Dublin. I love your city. We just returned from our third visit and we always have a blast.

kinverflyer

If you stall an air retract nothing happens until the load is taken off, if you stall an electric retract hopefully the overload cuts in, if it does not then severe damage will be done - burnt out motor, stripped gearbox or extreme cases an electrical fire.

electric eddie

Great to hear you enjoyed your trip to Dublin,Execllent city..im on the verge of buying a set of robart electric retracts for my H9 150 P51
and if the work out well ill get a set for my H9 150 P47 .. fingers crossed.. Anybody have any dealing with robarts website.Any problems with stock levels or postage??

chandley43231

My Feedback: (2)

how did they work out????

spaceworm

I have Wing electric retracts in a partially completed Complete A Pack P-47 from a recent swap meet. Can the electric motor/linear actuator be retrofitted with more modern stuff with servo-less electronics? Thanks

Sincerely, Richard

c550

My Feedback: (16)

I have one set of the Eflite retracts and they have worked well. I still prefer pneumatic for the sole reason that the biggest failure point outside of busting the metal frame is an o ring failure. It is hard to find but easy and cheap to fix. If the electronics go out it is going to be expensive.

My 2 cents

Shaun Evans

Hi,

Seems like I've read a bunch about teething issues with Robart electrics. I've seen plenty of issues with cheap Chinese ones and I had to send my controller back to HH on a brand new set of their P-51 gear. Pneumatics have been ultra-reliable over the years and when there were problems, there was no mystery to it. I'm in the 'don't fix what ain't broke' camp on most things. Having an electric air pump isn't such a burden to me.