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post #181 of 836 Old 12-16-2008, 06:45 PM - Thread Starter
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TeeCue,

This unit has so much going for it, I figured I would order one and see if I can't figure out a solution for the gearing. I would guess that the internal motor actually runs faster than one revolution per minute and there is internal gearing that slows the unit down. Maybe the internal gearing can be bypassed. ??????

Anyway, I just now ordered one from this site:

http://www.solidsignal.tv/prod_displ...p?PROD=ROTR100

For only $64.99 plus $9.95 shipping, I figured I'll at least get a bit of an education on Hall Sensors, plus I might even be able to make it work. (I also have another application that I might be able to use it for if I can't make it work for the masking.)
- Scott
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post #182 of 836 Old 12-16-2008, 08:12 PM
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Scott & TeeCue,

I think gearing is the way to go, from reading on a lot of small motors, a hobby 12Vdc motor that runs 100 RPM at 12V, if you cut the power to 6 Vdc, the RPM drops 1/2 to ~60 RPM.

Looking at Tamiya hobby motors, they achieve different RPM ranges via assembly of the gears within the gearbox. The motor shown below (from the Pololu web site) has six different gear ratios depending on how you assemble & arrange the gears. Food for thought....

http://www.pololu.com/picture/view/0J232

Picture of the Tamiya gear box # 72005
http://www.pololu.com/picture/view/0J234

Source for gears: http://www.servocity.com/html/gears___sprockets.html

Have learned that one must match the "Pressure Angle" & "Pitch" values when choosing gears to mesh properly with one another.


John
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post #183 of 836 Old 12-16-2008, 09:16 PM - Thread Starter
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John,

Thanks for the source for gears!

It seems to me that this whole topic of motorization should be a very simple issue. Just look at how many things in our everyday surroundings are motorized with gears and sensors... everything from car seats and windows to elevator doors to garage door openers. If a mechanical engineer with some basic knowledge of motors and gears read our posts, he would probably laugh at our fumbling around this topic.

At any rate, I think we are getting closer to a possible simple solution. If we can combine the antenna rotator motor unit with the proper gearing, maybe we can come up with a simple off-the-shelf programmable IR motorization system for less than $100. That would be cool!

Once I get the rotator unit, I will try to take it apart and post some pictures. You will have to be patient though; I am headed into my busy time of year at work (60 - 80 hour work-weeks)... so I won't have much time to work on my theater ...
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post #184 of 836 Old 12-16-2008, 10:04 PM
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Quote:
Originally Posted by ScottJ0007 View Post

John,

Thanks for the source for gears!

It seems to me that this whole topic of motorization should be a very simple issue. Just look at how many things in our everyday surroundings are motorized with gears and sensors... everything from car seats and windows to elevator doors to garage door openers. If a mechanical engineer with some basic knowledge of motors and gears read our posts, he would probably laugh at our fumbling around this topic.

At any rate, I think we are getting closer to a possible simple solution. If we can combine the antenna rotator motor unit with the proper gearing, maybe we can come up with a simple off-the-shelf programmable IR motorization system for less than $100. That would be cool!

Once I get the rotator unit, I will try to take it apart and post some pictures. You will have to be patient though; I am headed into my busy time of year at work (60 - 80 hour work-weeks)... so I won't have much time to work on my theater ...

I'm an engineering student and am not laughing at this discussion. Given the tools and "machinery" people have to make these, they are excellent.

Everything could be made easier by using stepper motors hooked directly to the rollers or maybe through a worm gear drive. Stepper motors can be had cheaply if you look around and there are many flavors of motor controllers which could use an IR input with the right inputs.

XBL Krimzen Rage
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post #185 of 836 Old 12-17-2008, 06:33 AM
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Scott, I think this is a very doable thing. John's links were very helpful, thanks John. Most of these high torque, low speed motors have a "worm gear"http://sadoun.com/Sat/Products/Power...G240%20005.jpg (the long screw like gear on the right side)
The rotation speed of this gear can be very close to what we need. If we can tap into the worm gear, it might just work. The picture is actually of a motor used to move a small sattelite dish. These are called HH motors (horizon to horizon).Their speed is 2.5 degrees per second ..even slower.
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post #186 of 836 Old 12-17-2008, 10:05 PM
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Quote:
Originally Posted by malovich View Post

I'm an engineering student and am not laughing at this discussion. Given the tools and "machinery" people have to make these, they are excellent.

Everything could be made easier by using stepper motors hooked directly to the rollers or maybe through a worm gear drive. Stepper motors can be had cheaply if you look around and there are many flavors of motor controllers which could use an IR input with the right inputs.

Malovich,
Using stepper motors is a great idea but the problem is finding an IR controlled device that has a digital display and presets for the position of the motor and having it interface with the motor controller.
If a computer was being used for the theater then it would be easy to control the motor(s) through RS232 protocol.You could control blinds, shades, a drop down projector even a automatic setup for the anamorphic lense....the possibilities are endless.
We are trying to keep it a simple DIY project using "off the shelf" components within a reasonable price range.
Again, your idea is a great one for those who can venture into the "stepper motor control arena"
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post #187 of 836 Old 12-23-2008, 02:33 PM
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What motor do they use in their masking system?
I can hardly understand him.
Video

Edgar
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post #188 of 836 Old 12-23-2008, 06:27 PM
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Originally Posted by Samaritano View Post

What motor do they use in their masking system?
I can hardly understand him.
Video

They are using the "Sonesse" motor made by Somfy.
http://www.usautomatedshade.com/cata...s&prod_type=36
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post #189 of 836 Old 12-24-2008, 11:10 AM - Thread Starter
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I received my Eagle Aspen Antenna rotor earlier this week. I think this thing just might work! It has 99 programmable stopping points, the IR is learnable by a universal remote, it will go directly from any given programmed position to any other programmed position without having to return to "zero", it is simple to use, and it costs less than $75 delivered!

The only problem remains the speed of the rotor; however, I think this can be fixed. I took the unit apart and found that it uses a rather small motor that runs at 6500 RPM. Through a series of four reducing gears, the rotation speed is slowed to about 1 RPM at the mast. I'm pretty sure I can come up with a fairly simple modification which will bring the rotation speed up to about 26 RPM. Combining this with about a 3 or 4 inch pulley, I think I can get the masking to move at a very acceptable speed.

I have taken some pictures of the disassembled unit and will post them when I get a bit more time.

(The Somfy motors discussed above are great motors. I actually have one of them in some automated blinds in my two-story family room. The issue with the Somfy motors is that they are quite expensive. If you have the money, they would be a great solution. But then, if you have the money, you might as well buy a commercial masking system.)

- Scott
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post #190 of 836 Old 12-24-2008, 11:23 AM
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Thanks Scott,

Looking forward to your photos.

Hope you have a wonderful & blessed Christmas,
A Merry Christmas to all !

John
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post #191 of 836 Old 12-24-2008, 12:06 PM
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Scott: They are expensive but sometimes good for one off mechanical designs or prototypes - www.sdp-si.com. They have some gearing and such, you may be able to make your own gearbox if you have some way to do some precision drilling. For less precise prototyping, you may be able to use one of many types of synchronous belts or synchronous "ropes". HTH. Scott
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post #192 of 836 Old 12-24-2008, 12:08 PM
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P.S. I'm a Somfy component dealer. I had planned on desigining a masking system myself but the CineSlide got too big and took all my time. Plus I didn't want to pay for another FCC and CE certification anytime soon . But if someone comes up with a plan using those tube motors, I can probably get you a deal on them. Merry Christmas, Scott
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post #193 of 836 Old 12-24-2008, 02:00 PM - Thread Starter
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----------------------------------------------------------------------------------------------------------------------------------------
UPDATE January 1, 2013 -- It is now MOTORIZED too!
 

 

PLEASE NOTE: In the next several hundred posts there is a lot of talk about a ton of motorization options. It is a good read and you can learn a lot from a bunch of knowledgeable people who contributed. However, the initial motorization option I adopted used the Eagle Aspen rotator discussed below. In December 2012 I abandoned this solution because the Eagle Aspen developed a history of malfunctioning for several people that tried it and it finally malfunctioned for me as well.

 

For me I also found that the whole idea of having a bunch of memorized presets was not nearly as useful as I had originally thought (This is only my personal opinion. Some people really like presets). My current motorization solution is greatly simplified. It is IR controllable from my Harmony Universal remote, there are limit stops for the fully closed and open points, but there are no presets. I simply hold down a button on the remote until the mask opens or closes to the point I want and then I let go of the button - easy, simple, fast.

 


- Jump to THIS POST to see more information on the motorization.


- Or see a video of the motorization HERE.

 


----------------------------------------------------------------------------------------------------------------------------------------

 

 

 

 

 

 

 

Thanks for the post to sdp-si.com. That is a great site.
If I were starting all over on my masking system and had a good source for Somfy motors, I think I would try to design the system around the use of tube motors. They have a LOT of advantages!


Here are the pictures of the Eagle Aspen rotor...

It is a little smaller than I expected, but that might be an advantage when trying to fit it in a small space:





Here's the unit with the bottom removed. On the inside of the casing, the gears and switches on the left are for stopping the motor once the mast rotates a full turn. This makes sense for an antenna rotor because you wouldn't want to twist the cables around the mast if it spun continuously. For our purposes, I think I will disconnect these switches.



Close-up of same thing as above:



Here, I have removed the gears that activate the switches. Getting the gears off was a bit of a pain. You need to have some retaining clip pliers. I used some small allen wrenches to gently pry the gears off of the shafts.
These gears need to be removed before you can take the mounting plate out of the housing.



This picture is looking up into the rotor housing. I found out the hard way that you need to keep the rotor upright when removing the internal mounting plate, otherwise all of the gears fall off the internal spindles.



This is the plate with motor and the gearing. You can see that the motor itself is quite small. The picture shows the gearing ratio of each gear and how the reduction to 1 RPM occurs.



- Scott

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post #194 of 836 Old 12-24-2008, 02:55 PM - Thread Starter
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Below are two diagrams of the last picture in my previous post. The first one shows the existing gear configuration and reduction:



My current thought is to change the gearing as shown in the following picture. I have not tried this yet, but in theory it should work -- and I'm hoping that it is relatively simple to accomplish...



I would welcome any thoughts or suggestions! I probably won't have time to actually work on doing this modification until later this coming weekend.

- Scott
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post #195 of 836 Old 12-24-2008, 07:53 PM
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Scott,

Great photos & drawings ! Cool looking piece of engineering. Looks like that might be an encoder board on the backside of the motor, so it can tell how much the shaft has turned & which direction maybe and the larger bd is the controller. Where does the IR sensor plug in ? Those limit swt inputs may come in handy sensing the limits of mask travel. Wonder how the controller bd will react when it sees light years more travel than it was expecting to see from the former one RPM gearing. Excuse me, I'm wondering all over the place.

I not even there & I am excited to see what you turn up !

Thanks for letting us look over your shoulder!

John
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post #196 of 836 Old 12-24-2008, 09:00 PM
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Great work Scott !

This motor does not have a worm gear. Your idea of connecting the first and the third gears would be the answer to we are looking for.
There are many ways to do that. The simplest would probably be to get a plastic or nylon disc or square piece (same thickness as the gears) and drill a hole in the center to accomodate the smaller gear of the first gear(B). Then, after thoroughly cleaning the surfaces, bond with JB Weld http://www.jbweld.net/products/industro.php

You will have to take the gears out and clamp everything till it cures. I dont think it is necessary but you can drill two small holes going through the three and put a cut off common pins there. The head of the pin will have to be flush. I have used the Dremel for such delicate projects. You can also use miniature machine screws and nuts but they will have to be flush on both sides.

Using the second gear(C), instead of a nylon disc, is also feasIble but grinding down the smaller gear may not be easy. Also it may be simpler not to disconnect the limit switches on the motor as they are part of the wiring and the motor may not function properly without them.

This configuration will give about 25 RPM on the rotator shaft.

I have used one of your diagrams, hope you don't mind.

This may turn out to be a great Christmas gift for the folks on the forum !!!

MERRY CHRISTMAS EVERYONE
LL
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post #197 of 836 Old 12-24-2008, 09:04 PM
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Quote:
Originally Posted by HDGTX View Post

Scott,

Great photos & drawings ! Cool looking piece of engineering. Looks like that might be an encoder board on the backside of the motor, so it can tell how much the shaft has turned & which direction maybe and the larger bd is the controller. Where does the IR sensor plug in ? Those limit swt inputs may come in handy sensing the limits of mask travel. Wonder how the controller bd will react when it sees light years more travel than it was expecting to see from the former one RPM gearing. Excuse me, I'm wondering all over the place.

I not even there & I am excited to see what you turn up !

Thanks for letting us look over your shoulder!

John

John,

The encoder is on the shaft (armature) of the motor. It will detect how many revolutions the shaft makes and has nothing to do what the final (geared) rotator RPM.
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post #198 of 836 Old 12-25-2008, 07:15 AM - Thread Starter
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Originally Posted by HDGTX View Post

Scott,

.... Where does the IR sensor plug in ? Those limit swt inputs may come in handy sensing the limits of mask travel.
John

John, The IR sensor is actually in a separate box. This antenna rotor is designed to have the receiver in the house by the television so there is a set-top box that has the IR sensor and positioning hardware built in. The only cable going to the motor housing is a single coax. Here is a copy of the picture from the SolidSignal.TV web site:

I probably will place the set-top receiver behind my false wall. I actually am thinking of buying three of these motors if I can get the gearing to work -- One for each side mask (although I could probably make a single one work), and one for my horizontal masking. I will put all three set-top boxes behind the false wall and hook them up to my Xantech IR control system and universal remote. I will program 5 locations on each receiver box:
Position "01" = the masking position for needed for 4:3
Position "02" = the masking position for needed for 16:9
Position "03" = the masking position for needed for 1.85:1
Position "04" = the masking position for needed for 2.35:1
Position "05" = the masking position for needed for 2.40:1
Then I can select a location and each receiver will send the information to its motor to move the masking to the proper location.

One drawback that I see when using multiple motors is that since all receivers respond to the same signal, if I press the IR remote button to manually move a motor, all three will respond. The only way to get a single motor to respond would be to turn off the receiver boxes for the other two motors. I think this is a rather minor issue though because once I program the locations for the pre-set masking ratios, I don't think I will need to make manual adjustments.

As for the limit switches, I have thought that it would be fairly easy to extend the wires and place the switches at the end points on my masking system. That way if something went wrong and the motors ran for too long, they would stop when the masking reached the end of its physical limit. (If I get the gearing all figured out, then I will look into the limit switch options when I actually install the motors.)

- Scott
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post #199 of 836 Old 12-25-2008, 07:33 AM - Thread Starter
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Quote:
Originally Posted by GetGray View Post

P.S. I'm a Somfy component dealer. I had planned on desigining a masking system myself but the CineSlide got too big and took all my time. Plus I didn't want to pay for another FCC and CE certification anytime soon . But if someone comes up with a plan using those tube motors, I can probably get you a deal on them. Merry Christmas, Scott

Scott,
Can the IR signal on the Somfy motors be "learned" by a Universal Remote?

For a future project, I want to set up my projector to drop down out of the ceiling. While I might be able to make one of these Rotor motors work, I think a tube motor might be my best option if I can find a good deal on one.

... .....humm.....After I finish this masking project, maybe I'll start a new thread on a DIY projector drop-down system........

- Scott
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post #200 of 836 Old 12-25-2008, 07:52 AM - Thread Starter
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Quote:
Originally Posted by TeeCue View Post

.... Most of these high torque, low speed motors have a "worm gear"http://sadoun.com/Sat/Products/Power...G240%20005.jpg (the long screw like gear on the right side)
The rotation speed of this gear can be very close to what we need. If we can tap into the worm gear, it might just work. The picture is actually of a motor used to move a small sattelite dish. These are called HH motors (horizon to horizon).Their speed is 2.5 degrees per second ..even slower.

I was looking at the Sadoun.com web site and I think the motor they use in their system is very similar to the one used in the Rotor I have. The Sadoun motors are similarly priced to the Eagle Aspen, but do not include the IR remote and the receiver. However the Sadoun's might be an option for someone who needed a worm drive for their particular setup rather than a rotating shaft like I will have on the Eagle Aspen setup.

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post #201 of 836 Old 12-25-2008, 08:12 AM - Thread Starter
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Quote:
Originally Posted by TeeCue View Post

.... Your idea of connecting the first and the third gears would be the answer to we are looking for.
There are many ways to do that. The simplest would probably be to get a plastic or nylon disc or square piece (same thickness as the gears) and drill a hole in the center to accomodate the smaller gear of the first gear(B). Then, after thoroughly cleaning the surfaces, bond with JB Weld http://www.jbweld.net/products/industro.php ......
This may turn out to be a great Christmas gift for the folks on the forum !!!

Merry Christmas!

I like the idea of using a plastic or nylon disc. This might be a lot easier than grinding off the small gear. The trick will be finding a disc with the right thickness. I've never used JB Weld before, but I know a lot of people swear by it. Thanks for the suggestion.

I wonder if there will be an issue with the balance of the gear after welding it together. Since it will be spinning at 1300 RPM will there be any issues if it isn't balanced perfectly? Any thoughts?
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Merry Christmas!

I like the idea of using a plastic or nylon disc. This might be a lot easier than grinding off the small gear. The trick will be finding a disc with the right thickness. I've never used JB Weld before, but I know a lot of people swear by it. Thanks for the suggestion.

I wonder if there will be an issue with the balance of the gear after welding it together. Since it will be spinning at 1300 RPM will there be any issues if it isn't balanced perfectly? Any thoughts?

There should be no problems with balance as both the gears will be on the same shaft. The bonding compound should be used in a way that it is equally spread and there is no accumulation on any side.

If the shaft of the motor was a little longer things would be much easier. One could get rid of the B and C gears and put a spacer (washer, bearing) of a smaller diameter but same thickness in their place. This would bring gear A directly in contact with gear D. I am also looking around to see if there is a longer version of the gear A available anywhere.

Can you tell me how the shaft of the gear E is embeded? Can this be taken out ? What I am thinking is that if the base of the housing of this shaft is shaved off a little then gear E will drop down to the level of gear D (C removed and B replaced by a washer HALF the the total thickness of B). Then the position of F can be adjusted with spacers or bearings, these are readily available at hobby shops.....Crazy but doable...this is a DIY forum after all... I will show this on one of your drawings later today.
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Quote:
Originally Posted by ScottJ0007 View Post

I was looking at the Sadoun.com web site and I think the motor they use in their system is very similar to the one used in the Rotor I have. The Sadoun motors are similarly priced to the Eagle Aspen, but do not include the IR remote and the receiver. However the Sadoun's might be an option for someone who needed a worm drive for their particular setup rather than a rotating shaft like I will have on the Eagle Aspen setup.


I have read somewhere that a worm gear setup has an added advantage of preventing creep, acting sorta like a mechanical brake. That would be helpful to prevent spring tension in a roller from gradually pulling the mask back towards the roller. Does that make sense ?

John
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post #204 of 836 Old 12-25-2008, 01:04 PM - Thread Starter
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Originally Posted by TeeCue View Post

Can you tell me how the shaft of the gear E is embeded? Can this be taken out ? What I am thinking is that if the base of the housing of this shaft is shaved off a little then gear E will drop down to the level of gear D (C removed and B replaced by a washer HALF the the total thickness of B). Then the position of F can be adjusted with spacers or bearings, these are readily available at hobby shops.....Crazy but doable...this is a DIY forum after all... I will show this on one of your drawings later today.

The shaft of gear E is embeded into the metal base. I can't budge it with my fingers. I'm a little reluctant to use pliers on it yet because I don't want to damage it.
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post #205 of 836 Old 12-25-2008, 01:09 PM - Thread Starter
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Originally Posted by HDGTX View Post

I have read somewhere that a worm gear setup has an added advantage of preventing creep, acting sorta like a mechanical brake. That would be helpful to prevent spring tension in a roller from gradually pulling the mask back towards the roller. Does that make sense ?
John

John,
Yes that makes a lot of sense -- Very good point. That would definitely be a factor for anyone with masking that is tensioned with spring rollers. In my case, there is no spring tension so it is not a concern. Any system with tension would need some type of breaking mechanism on the motor to prevent creepage.
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post #206 of 836 Old 12-25-2008, 01:24 PM
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Originally Posted by HDGTX View Post

I have read somewhere that a worm gear setup has an added advantage of preventing creep, acting sorta like a mechanical brake. That would be helpful to prevent spring tension in a roller from gradually pulling the mask back towards the roller. Does that make sense ?

John

You are absolutely correct. That is the biggest advantage of worm drives. The most common use that we see is in car jacks (a variant of the worm concept), even the weight of the vehicle does not make the worm gear turn backwards.

In Scott's set up, if the springs are not pulling the masking back currently, then it would not be a problem. The gears definitely have a braking / holding effect and should do just fine. On the other hand, I would not recommend using a tubular gear drive motor to move a projector up and down !!!
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post #207 of 836 Old 12-25-2008, 01:43 PM
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Originally Posted by ScottJ0007 View Post

The shaft of gear E is embeded into the metal base. I can't budge it with my fingers. I'm a little reluctant to use pliers on it yet because I don't want to damage it.

OK, lets not mess around with that. I think the bonding would be just fine. Have to be careful that no compound gets on to the gear teeth and the inner bore.

If you have a universal remote that can be programmed with a pause or delay between commands, then it would be very easy to control two or more motors with one remote control, all the motors responding independantly of each other.

The limit switch idea to control a run away motor is a good one.

I stand to correct my self regarding an earlier post regarding keeping the internal limit switches. Those switches will have to be bypassed as they will stop / reverse the motor after the first full revolution of the rotor. We need the rotor to go more than that!!

On the other hand, bypassing the switches may interfere with the calibration of the unit which can be very problematic.

Can you PM me the owners manual and the schematic if available.........Getting complicated !!!!!!!!
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Scott,

The gear (A) on the motor is also called a Pinion Gear. A lot of local hobby shops that sell RC cars, planes or helicopters sell these. If you can find one that is long enough to engage gear D, then the problem is solved.

http://www.rcdude.com/servlet/the-Pi...ars/Categories

What do you think about the concerns I raised in post # 207.
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post #209 of 836 Old 12-25-2008, 08:31 PM
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More wonderings...

Here's a link to ServoCity's shaft couplers to lengthen the motor shaft, but you might have to move the motor further away from the bottom plate (on stand offs?) so the coupler won't rub on the lower gear. The second link is for shafts, they also have pinions. Not sure if the motor's shaft is metric or inch std. I am sure other places sell them as well (like the sdp-si.com place).

http://servocity.com/html/pinion_gears.html

http://servocity.com/html/shafts__rod___tubing.html

SDP-SI has long shafted pinions that might work with the coupler, once the motor has been moved further away. See Inch products, then gears, then Spur gears, then Metal-pinion shafts, could not grab a direct link.

Those two factors when meshing gears pop up here, that Pitch & Pressure Angle values must match. A store that sells gearing should be able to measure that. But, using the pinion you already have would alieve those issues once mounted on a longer shaft.

John
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post #210 of 836 Old 12-26-2008, 07:22 AM - Thread Starter
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Quote:
Originally Posted by TeeCue View Post

If you have a universal remote that can be programmed with a pause or delay between commands, then it would be very easy to control two or more motors with one remote control, all the motors responding independantly of each other.

I have a Logitech Harmony One. If we get the motor gearing resolved and when I get to the point of programming the control, we'll talk more about this.

Quote:


The limit switch idea to control a run away motor is a good one.

I stand to correct my self regarding an earlier post regarding keeping the internal limit switches. Those switches will have to be bypassed as they will stop / reverse the motor after the first full revolution of the rotor. We need the rotor to go more than that!!

On the other hand, bypassing the switches may interfere with the calibration of the unit which can be very problematic.

I've wondered about this issue of the calibration. The unit does have a "resynchronization" process that you can run if it gets out of calibration. I've wondered if this uses the limit switches to find the "zero" point and reset itself. I'll play with this a bit more once the gearing problem is resolved. I'm sure we can come up with a solution to the calibration issue.

Quote:


Can you PM me the owners manual and the schematic if available.........Getting complicated !!!!!!!!

I'll need scan it to a PDF file. I don't have a scanner available now, but I'll get it to you in the next couple of days.

Quote:
Originally Posted by TeeCue View Post

The gear (A) on the motor is also called a Pinion Gear. A lot of local hobby shops that sell RC cars, planes or helicopters sell these. If you can find one that is long enough to engage gear D, then the problem is solved.
http://www.rcdude.com/servlet/the-Pi...ars/Categories

Quote:
Originally Posted by HDGTX View Post

Here's a link to ServoCity's shaft couplers to lengthen the motor shaft, but you might have to move the motor further away from the bottom plate (on stand offs?) so the coupler won't rub on the lower gear. The second link is for shafts, they also have pinions. Not sure if the motor's shaft is metric or inch std. I am sure other places sell them as well (like the sdp-si.com place). http://servocity.com/html/pinion_gears.html http://servocity.com/html/shafts__rod___tubing.html SDP-SI has long shafted pinions that might work with the coupler, once the motor has been moved further away. See Inch products, then gears, then Spur gears, then Metal-pinion shafts, could not grab a direct link.

Those two factors when meshing gears pop up here, that Pitch & Pressure Angle values must match. A store that sells gearing should be able to measure that. But, using the pinion you already have would alieve those issues once mounted on a longer shaft.John

I like the idea of extending the pinion gear. If I can find the right coupler and extension I think this will be a quick and easy solution to the gearing issue. I have a hobby store close to me that I will stop by today to see if they can help with this. Maybe they can help me with the pitch and pressure angles, as well as the correct shaft diameter.

I still believe we can come up with a simple to implement modification for this rotor that will make it an excellent option for anyone who wants to motorize a DIY masking system. I think we are getting closer.
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