Electric Retracts - Modifying existing Air/Servo-operated Retracts
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Electric Retracts - Modifying existing Air/Servo-operated Retracts
Well, after having given up on Lado... ([link]http://www.rcuniverse.com/forum/m_8425919/anchors_8425919/mpage_1/key_/anchor/tm.htm#8425919[/link]) ,the DIY guy that I am... I designed my own DIY version last night...
Here's a vid of the first prototype.... used a miniature 50:1 gear motor attached to a pc. of 4-40 threaded rod that pushes/pulls the existing mechanism of an older (Hobbico?) servo-operated retract mechanism. My next project will be retrofit actuators for my Robart 630 retracts (easier actually)... but still awaiting a few custom couplers my Dad is machining for me... Next task is to design the controlling electronics (will use a 8-pin PIC interfaced to an H-bridge with current sensing circuitry to sense end positions... no limit switches needed). Might soon be looking for a CNC manufacturer! [8D]
[youtube]http://www.youtube.com/watch?v=y1-hInYnsw0[/youtube]
Here's a vid of the first prototype.... used a miniature 50:1 gear motor attached to a pc. of 4-40 threaded rod that pushes/pulls the existing mechanism of an older (Hobbico?) servo-operated retract mechanism. My next project will be retrofit actuators for my Robart 630 retracts (easier actually)... but still awaiting a few custom couplers my Dad is machining for me... Next task is to design the controlling electronics (will use a 8-pin PIC interfaced to an H-bridge with current sensing circuitry to sense end positions... no limit switches needed). Might soon be looking for a CNC manufacturer! [8D]
[youtube]http://www.youtube.com/watch?v=y1-hInYnsw0[/youtube]
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Hey... I'm curious.... how many of you would rather retrofit existing air/servo-controller retracts (i.e. Robart, Century, etc...) with an actuator replacement (remove air cylinder & replace with electric actuator).... rather than buying a complete set that is electrified? Just trying to see if there is a market/need for just the actuators.
If any one also has any comments/suggestions... please reply.
If any one also has any comments/suggestions... please reply.
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
I’m very interested in several sets of them, you better get to work and sort them out, just add customer service and you will have LADO beat hands down & customers will beat a path to your door
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Looks good so far...just don't forget to add a torque limiter or such so that if the gear do hang up somehow, they shut down rather than burn out...or is that what you mean when you mention a current sensing circuit?
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Breaking news from Doug at Lado's himself...
http://www.rcuniverse.com/forum/m_84...tm.htm#9269674
Not sure how this will ensure a reliable supply in the future....
http://www.rcuniverse.com/forum/m_84...tm.htm#9269674
Not sure how this will ensure a reliable supply in the future....
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
ORIGINAL: jim pettis
Looks good so far...just don't forget to add a torque limiter or such so that if the gear do hang up somehow, they shut down rather than burn out...or is that what you mean when you mention a current sensing circuit?
Looks good so far...just don't forget to add a torque limiter or such so that if the gear do hang up somehow, they shut down rather than burn out...or is that what you mean when you mention a current sensing circuit?
Yes.... my idea of a current sensor (built into H-bridge chip I plan to use) will hopefully allow me to sense increase current at both ends of throw... motor would hence stop automatically. It would also stop any time it senses an increase in current due to unexpected binding (i.e. obstacle). I ordered a sample chip ([link=http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MC33887&fsrch=1]Freescale MC33887[/link]) and will experiment more when it comes in. Some PIC code will also have to be written but should not be all too difficult... so I hope!
Right now, I'm thinking of seperating the controller from the mechanism... not only to save space in/on the retract, but to also protect the controller from the elements, sheilding it inside the aircraft. Plus it probably wouldn't be too hard to have one servo controller board control MANY servos for various applications (maybe even with onboard options such as speed, stagger, delay, etc... functions). I also pondered the idea of auto retracts where when the aircraft (controller) senses altitude (via sensor) and when a preset altitude is reached, the retracts automatically are triggered, bringing up the gear.
I am more of a small DIY parts guy (supply small elec gadgets, kit parts, etc...) so if any one else is interested is a possible partnership of some type... please PM.
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
ORIGINAL: jim pettis
Breaking news from Doug at Lado's himself...
http://www.rcuniverse.com/forum/m_84...tm.htm#9269674
Not sure how this will ensure a reliable supply in the future....
Breaking news from Doug at Lado's himself...
http://www.rcuniverse.com/forum/m_84...tm.htm#9269674
Not sure how this will ensure a reliable supply in the future....
This is sooooo funny.....
....
One other thing…. Who ever is calling and filling up my voicemail is really out of line. I have contacted my phone company and they will be tracing these callers.
Thanks,
Doug - LADO Tech
One other thing…. Who ever is calling and filling up my voicemail is really out of line. I have contacted my phone company and they will be tracing these callers.
Thanks,
Doug - LADO Tech
Now this is just a guess... It might in fact be his "customers" looking for the gear they paid for months ago...
Just a hunch....
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
....
One other thing…. Who ever is calling and filling up my voicemail is really out of line. I have contacted my phone company and they will be tracing these callers.
Thanks,
Doug - LADO Tech
One other thing…. Who ever is calling and filling up my voicemail is really out of line. I have contacted my phone company and they will be tracing these callers.
Thanks,
Doug - LADO Tech
Now this is just a guess... It might in fact be his ''customers'' looking for the gear they paid for months ago...
Just a hunch....
[/quote]
I had the same exact thoughts...hmm, wonder if he considers my daily calls for info harassing as well. Good thing I leave a call back number every time. Will save the "phone company" some time there.
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
I love it! Now I have a use for all those old can electric motors I have about the shop!
Following this thread with a lot of interest. Lots of questions, but will hold them for now.
Love it!
Tommy D
Following this thread with a lot of interest. Lots of questions, but will hold them for now.
Love it!
Tommy D
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
ORIGINAL: kodi7
A replacement for the air cylinder sounds like the way to go.
A replacement for the air cylinder sounds like the way to go.
I hope to find some time this week to tinker a bit with my 630 Robart air-retracts... have some ideas to prove out... and once I get these 630s mod'd, I'll try to post some details/pics.
Any one else looking to get involved in working out the CNC/manufacturing details?? [8D]
As a minimum, a clam-sheel style aluminum case for the motor would need to be designed... got some ideas to share but I'm not a big-time CAD guy...
p.s. I also need a little help with some other gear that is out there, which I don't have in hand to observe....
I'm curious in regards to the type of mechanics that is used which pulls/pushes the mechanism. My Robarts use a steel cylinder that rides along to CNC slots milled into the two sides of the mechanism, which in turn rotates/locks the gear up and down. The air cylinder's rod, that extends or retracts, is then attached to this steel cylinder (the rod threads into the steel cylinder... usually with red loctite to lock it in good). I'm curious is any one knows the thread/size of this controlling rod, as the electric retract mechanism will need to use the similar threaded rod (avoiding having to re-tap the steel control cylinder). If I have time,... I'll psot some oics of what I am talking about... The other option is to provide various cylinder of various sizes and various threaded holes for the threaded control rod... I'm certain these are probably model-specific...
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
ORIGINAL: _Tommy D
I love it! Now I have a use for all those old can electric motors I have about the shop!
Following this thread with a lot of interest. Lots of questions, but will hold them for now.
Love it!
Tommy D
I love it! Now I have a use for all those old can electric motors I have about the shop!
Following this thread with a lot of interest. Lots of questions, but will hold them for now.
Love it!
Tommy D
These gear motors I'm using are built will all-metal gears... and tiny as heck (but alot of torque)
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
They look a lot like the old, what we used to call J250s motors. <orig app electric shavers I think> Had a bucket full of them at one time =)
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
So whats a motor gear box unit like that cost and where do you get one?
The key element here is going to be the electronics I think.
Lots of guys could do their own motor gear box mods - if they had a source for the parts.
The electronics will stump most of us though.
Probably the majority will want a plug-n-play setup though.
The key element here is going to be the electronics I think.
Lots of guys could do their own motor gear box mods - if they had a source for the parts.
The electronics will stump most of us though.
Probably the majority will want a plug-n-play setup though.
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
$18.99 Robot Marketplace
http://www.robotmarketplace.com/products/IL-SAN50.html
There are cheaper suppliers if you want to buy in bulk. Its a fairly common antweight (combat robot class) drive motor. Different gear reductions are available.
For the electronics, just dismantle a standard size servo. Remove the motor and wire in the new gearhead motor. Remove the potentiometer and wire in a new 5k linear potentiometer that is attached to the nut of the retract mechanism. Seal the servo board with heatshrink and some hot glue. Instant proportional retract mechanism that can plug right into your receiver. You can program the endpoints with your transmitter.
http://www.robotmarketplace.com/products/IL-SAN50.html
There are cheaper suppliers if you want to buy in bulk. Its a fairly common antweight (combat robot class) drive motor. Different gear reductions are available.
For the electronics, just dismantle a standard size servo. Remove the motor and wire in the new gearhead motor. Remove the potentiometer and wire in a new 5k linear potentiometer that is attached to the nut of the retract mechanism. Seal the servo board with heatshrink and some hot glue. Instant proportional retract mechanism that can plug right into your receiver. You can program the endpoints with your transmitter.
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
The gear motor is manufactured by Sanyo. Part number 12GN-0348. You may search for "12mm gear reduction motor" to find similar products.
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
i would sure be interested if you make them for giant scale, got a couple sets of robarts that would be great electric
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
ORIGINAL: hands without shadows
$18.99 Robot Marketplace
http://www.robotmarketplace.com/products/IL-SAN50.html
There are cheaper suppliers if you want to buy in bulk. Its a fairly common antweight (combat robot class) drive motor. Different gear reductions are available.
For the electronics, just dismantle a standard size servo. Remove the motor and wire in the new gearhead motor. Remove the potentiometer and wire in a new 5k linear potentiometer that is attached to the nut of the retract mechanism. Seal the servo board with heatshrink and some hot glue. Instant proportional retract mechanism that can plug right into your receiver. You can program the endpoints with your transmitter.
$18.99 Robot Marketplace
http://www.robotmarketplace.com/products/IL-SAN50.html
There are cheaper suppliers if you want to buy in bulk. Its a fairly common antweight (combat robot class) drive motor. Different gear reductions are available.
For the electronics, just dismantle a standard size servo. Remove the motor and wire in the new gearhead motor. Remove the potentiometer and wire in a new 5k linear potentiometer that is attached to the nut of the retract mechanism. Seal the servo board with heatshrink and some hot glue. Instant proportional retract mechanism that can plug right into your receiver. You can program the endpoints with your transmitter.
Im not sure Im following you on the servo parts use. These are going to need to turn several full 360 degree revolutions to go from UP to DOWN.
Oh wait - thats what the linear pot is for?
If Im understanding you thats a cool suggestion!
That would work well for everything except the gear getting jammed. A current sensor would still be needed I think. Or at least a nice addition.
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Yup... you guys are right... Sanyo gear motors they are, with a 50:1 ratio. This allows me to spin my 4-40 rod (that drives the retract actuator) at such a speed that it takes roughly 4-5 seconds to retract or deploy... Many Robotics outfits sell them.... and the ones I have were purchased from Pololu.com
As for the electronics, you certainly could use scrap servo parts but there is really no reason to make these "proportional", using a feedback pot. To sense limits, I plan to use the increase in current when it reaches both ends, rather that limit switches and/or a feedback pot. Attaching a potentiometer to this mechanism is not all that easy either... look at my setup and you'll see what I mean... no easy way to connect to the nut being driven my the threaded rod.
Now,... the bad/good news, I recently got contacted by a few manufacturers/reps who are very interested in this idea (certainly can't say names) but I can tell you, there is definitely the possibility that these retrofit actuators could be on the market faster than some think. Some probably don't know this but some of the big-name retract Co. are also looking into selling their gear but with electric actuators... in fact some one mentioned that a few of them might had already contacted Lado re: supplying them the actuators for their use (possibly his new bussiness plan). The bad publicity Lado took the last 3-4 months might had ruined this coop... and it now appears they might be looking for other solutions... possibly purchasing the design and bringing the manufacturing in-house.
So... bottom line... If I decide to work with these fellas... you won't see any more posts here re: my DIY retracts effort unfort.
...time will tell...
As for the electronics, you certainly could use scrap servo parts but there is really no reason to make these "proportional", using a feedback pot. To sense limits, I plan to use the increase in current when it reaches both ends, rather that limit switches and/or a feedback pot. Attaching a potentiometer to this mechanism is not all that easy either... look at my setup and you'll see what I mean... no easy way to connect to the nut being driven my the threaded rod.
Now,... the bad/good news, I recently got contacted by a few manufacturers/reps who are very interested in this idea (certainly can't say names) but I can tell you, there is definitely the possibility that these retrofit actuators could be on the market faster than some think. Some probably don't know this but some of the big-name retract Co. are also looking into selling their gear but with electric actuators... in fact some one mentioned that a few of them might had already contacted Lado re: supplying them the actuators for their use (possibly his new bussiness plan). The bad publicity Lado took the last 3-4 months might had ruined this coop... and it now appears they might be looking for other solutions... possibly purchasing the design and bringing the manufacturing in-house.
So... bottom line... If I decide to work with these fellas... you won't see any more posts here re: my DIY retracts effort unfort.
...time will tell...
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Good luck with it Tom!!
I would still like to see an offering of DIY components. I dont think that would cost much in the way of sales. There are not that many guys who would do the work on their own.
In particular, I would like to see a current sensing cut off device. I still think thats the key stumbling block to DIY'ers.
I would still like to see an offering of DIY components. I dont think that would cost much in the way of sales. There are not that many guys who would do the work on their own.
In particular, I would like to see a current sensing cut off device. I still think thats the key stumbling block to DIY'ers.
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Sure Larry... I'll certainly keep that in mind for the DIY'ers.
After I get some electronics working... I'll try to post some vids and some specs, etc...
Like you said, the electronics are quite an important part of these... it could make or break the idea actually...
After I get some electronics working... I'll try to post some vids and some specs, etc...
Like you said, the electronics are quite an important part of these... it could make or break the idea actually...
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
Well... I was able to easily modify one of my large-scale Robart retracts to operate electrically rather than via air....
Here's the first vid..... works amazingly well for a large/heavy gear mechanism... that's a 4" wheel there... (this was pulled from my 1/4 scale A6M5 Zero).... can't wait to start working the electronics....
[youtube]http://www.youtube.com/watch?v=pILrwAKbSIY[/youtube]
Cool or what? [8D][8D]
Here's the first vid..... works amazingly well for a large/heavy gear mechanism... that's a 4" wheel there... (this was pulled from my 1/4 scale A6M5 Zero).... can't wait to start working the electronics....
[youtube]http://www.youtube.com/watch?v=pILrwAKbSIY[/youtube]
Cool or what? [8D][8D]
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RE: Electric Retracts - Modifying existing Air/Servo-operated Retracts
I'll take 2 thank you. Looks like a ton of power, and I actually like the speed compared to the Lado. Nothing like a dead stick and your gear taking 10 seconds to drop.....
It would be great if these or something like it were READILY available. I'm getting ready to put together the Hangar 9 Spitfire, and will have to deal with undersized gear wire, servo set up, etc. Would be much happier tossing a pair of Robostruts and electric retracts in.
Good luck.
It would be great if these or something like it were READILY available. I'm getting ready to put together the Hangar 9 Spitfire, and will have to deal with undersized gear wire, servo set up, etc. Would be much happier tossing a pair of Robostruts and electric retracts in.
Good luck.