ModellbauUK

Although these are still relatively still in their infancy I wonder what's the key difference between these 2 manufacturers.

Do their systems work on a different system of control? Stall current or turn wind on the retracts.

Electron main wheels brakes only go up to 80mm wheels. Correct?

Which is the better option & are there better options on the market?

Thanks

Ian

number27

I can't compare both systems and I don't have both. I have two sets of electrons with their brakes ER40 retract unit and ER50 retract unit. Both are fantastic. Went with the Electron as more readily available to me. The cost was also better with the Electrons. Looked at the Behotec's went with a supplier (RCMOLD) who then cancelled my order as Behotec had changed their shipping policy monies refunded.

Would go with them again. Now that Dreamworks have a drop in replacement for their Taurus retract units I will try them as I have two sets of retract air untis doing nothing but jack now. perfect to go in my 2nd hand Yellow F15 that's on its way.

tp777fo

My Feedback: (28)

I have Electrons on my Ultraflash....outstanding gear. Impressive solid aluminum blocks. Smooth operation. I ran off the runway and bent the drive gear on nosegear New parts were sent the next day and I received them in less than a week. That's great service. I wont hesitate to buy electons again

John Tancock

Ian
I prefer encoder technology, it doesn't make the wheel and leg weight so critical!

Behotech have legs on everyone else at the moment, excuse the pun!



JT

See U @ the AGM!

siclick33

How so?

As long as the unit has the power to lift the leg then surely the stall current system works fine. If the unit isn't powerful enough to lift the leg then encoder systems won't help. Do the encoder systems not have stall current safety backups anyway?

John Tancock

Yes they do!
But using stall current for end points makes leg and wheel weight more critical!

It's just my preference, it's not a bad thing, it just means with encoders the stall current can be adjusted to suit the weight of the legs without issues of the trunnions becoming jammed at their end points. With just stall current, it can become a little bit of a balancing act!
Or would you disagree?
I use both systems in industry and using stall current is a lot cheaper than using encoders (at the moment anyway)!

(Good thread for discussion)


JT

Dave Wilshere

I'm with JT...[X(]

Heard of too many issues with the other lot...but no one using Behotec yet, so will see in another year.

Dw

siclick33

I don't have enough experience with either systems to be able to present an opinion based on practical use. The only electric gear I have used for any appreciable duration is the little E-Flite gear.

Just from my idle thought processes thinking about how leg weight would affect the gear I have considered, what might be considered the worst case, with a heavy leg. Assuming a 90 degree gear then with the heavy leg down then the 'force' on the retract will be relatively small as the leg is hanging in it's natural state. When nearly retracted, the leg will be providing the greatest resistance as it wants to flop down. This would mean a higher current drain during retraction and therefore the stall current would be reached earlier with less 'force' on the trunion than if a lighter leg was used. I accept that not all retract setups are the 'traditional' installation that I have considered. I can't see that the trunion would be likely to get jammed but, as I say, I have no real-life practical experience.

The main problems that can be associated with electric gear such as dirt/grit fouling the screws and mechanisms etc would be just as bad with an encoding system as the stall current safety system might kick in before the end points are reached anyway. This might be more likely to happen when retracting a heavier leg but is this less likely to happen with an encoding system?

I'm more than happy for my ramblings to be shown to be rubbish, either by fact or by someone simply passing on their practical experiences. I am seriously considering electric gear for my next model and anything that can lean me to or from a particular system is good for me. I'm not necessarily denying that encoding systems are better, just that the stall current method appears to me to be perfectly acceptable for our use.

Out of interest, do the commercially available retracts with encoding systems allow for user adjustment of the end points?

John Tancock

I think it is possible with the Behotech system, although you do have a fare point, and if you are operating any of these systems off of grass, then regular cleaning will be necessary! It may sound stupid but lubrication in these cases is not suitable as it tends to atract a build up of foriegn bodies!
Internal screw jacks would be more suitable using a revolving internal thread, then a wiper could be used on the exposed part of the push/pull rod as in a pneumatic ram! Internal thread systems are being utilised on gear door actuators by Lado!

Still a way to go with electric systems, in the end I think it will be the preferred way due to ease of installation as in pneumatics, and with the safe guard that there will be no air leaks!

By the way I do not sell any of these systems, and so therefore I am not promoting any barand, these are just engineering observations based on the products that are already in the market!

I must say that I am impressed with the ingenuity of all the companies involved in developing these units, especially with the level of quality against the price!

paulhat

I have 2 sets of electron Er40's that have functioned perfectly since new. I would say I have had about 120 flights total on the 2 sets.
All flights have been off a dirt runway that gets very dusty. Especially this time of the year.
I have had no problems with them being fouled up with dirt at all.
To be honest I dont think dirt affects these systems as much as people think. My strip would have to be about as dusty as you could get.
I would never go back to pneumatic after using the electrons.
Hopefully going to be trying out a set of Behotecs soon.


Regards,

Paul.

John Tancock

Hi Paul
Would it possible to show the units installed your aircraft, just for reference?
What sort of weight are the legs/wheels? It will give a better idea on how obtain a successful set up!
Do you bother to clean the units at all?

All the best



John.

paulhat

Hi John,
I have one set installed in a PST reaction. The other set in an Ultra Flash.
Both have prolink legs.
The PST is using Intairco wheels and the Ultra Flash uses the electron electric brake wheels.
I have never cleaned them (probably should though )
Have to put the planes together to get pictures.
I am lazy so that probably won't happen until I fly next weekend.

Paul.

John Tancock

Cool! LOL


John

paulhat

Yeah it is bad hey
But seriously there is not much to know when it comes to these electric retracts.
I wouldn't worry about set up at all. Just chuck them in as you would any other pneumatic retract and you will be fine.
They lift the legs and wheels I use no problem at all.
You have to push on them with quite some force to activate the current limiter. If you have to push that hard in the air there is something really wrong anyway.
For me the greatest benefit is not having to worry about air leaks. I know you can get low pressure gear downs and all that but what a hassle.
Electric retracts, gear doors and brakes will be the standard soon.

Paul.

number27

I have a set of ER40's in a PST Reaction with Prolinks and the Electron Brakes great system drop in and run some servo wire and that's it. The PROLINKS are the weak part in the system. Posted elsewhere about these OLEO's. Have over 150 flights and only cleaned the Prolinks OLEO's and a wipe of the outer parkt of the retract.

ALso have a set of ER50's in the Eurosport again with Prolinks. They are a great drop in unit to replace air. Never go back to air. Highly recommended.