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Author Topic: Sidewinder -- double MUT Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 07-18-2007 04:27 AM                     Hello! I've got some idea to make sidewinder by mine own......but got problem's with drive motors....I try to do something like Meopta with asynchrony motors and resistor in serial with it....but I've get motors over heat too much! Another idea is to put DC motors with regulation, and get regulation from arm lik on ernemann or kinoton. Any ideas or help with choosing motors....or may bee somebody do this also?  |  IP: Logged Robert Minichino Master Film Handler Posts: 350 From: Haskell, NJ, USA Registered: Dec 2005 posted 07-18-2007 08:57 AM                        You need "torque motors." They are designed to have their shaft stationary when power is applied to them without overheating.  |  IP: Logged Michael Moore Expert Film Handler Posts: 188 From: Dover, DE / USA Registered: Jun 2006 posted 07-18-2007 11:38 AM                        I hope I read your post right, so if this is bad advice them I'm sorry. I built my own single sided MUT from speco parts (LP271). I took their motor, and electronics and built my own box, and then put legs on it and put a a pole assay from Christie. works great. I call is frankenMUT I have started to build my own rewind table with a DC motor from a tread mill. These motors work great and are torque motors, Remember if you use one you need the control board and a pot to increase and decrease the speed. Also they are revisable and you can stop them almost on a dime. You can take them out of old Tread Mills or buy them on eBay or find them in in a Surplus store. good luck.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 07-18-2007 12:21 PM                     People may make jokes, but at least the frankenMUT has a place for a splicer, unlike many "professional" MUTs. Nice work.  |  IP: Logged Michael Moore Expert Film Handler Posts: 188 From: Dover, DE / USA Registered: Jun 2006 posted 07-18-2007 12:42 PM                        thanks Brad, I was going to stain the wood and then paint the name FrankenMUT on the side in gold letters. I was going to call it the Franken-MUT 2000, but I have too many projects now on my plate.  |  IP: Logged Catalin Balaceanu Film Handler Posts: 36 From: Pascani, Iasi, Romania Registered: Mar 2006 posted 07-18-2007 02:45 PM                        Hi Marin, I hapen to be working on the same thing, following the same Meopta approach. The type of motor you need is also called (at list around these parts) "Hysteresis Motor". I know somebody that...knows somebody who imports them from Hungary. So this might be a good place to look for them. Another approach I'm considering, is using a friction assembly from an old projector (which I already have) and a low RPM motor, or even the old projector's motor. Michael, your FrankenMUT looks sweet. Nice work! Catalin www.catalinbalaceanu.com  |  IP: Logged Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 07-18-2007 04:20 PM                     I have one MEOPTA motor.....they where (or still they are) produced by MEZ MOHELNICE The major thing on this so called "Hysteresis Motor" is that they have shorted rotor and big loses in hysterese...so effieny is about 30%....with 120W electrical power, you've get 10W of drive power..and they can be stopped without overheating problems. Friction assembly from projector isn't good solution because all of this are made up to max 1800 meter....and on 1800 some have problems to drive full rell! Best solution is to use DC motor with gear or belt drive to film rell and which gonna be regulated with potentiometer which is moving by arm with roller, which is stretched by film moving to rell, and then potentiometer gonna regulate voltage to DC motor true some DC regulator....  |  IP: Logged Michael Moore Expert Film Handler Posts: 188 From: Dover, DE / USA Registered: Jun 2006 posted 07-18-2007 06:10 PM                        What you need is PWM controller for a DC torque motor. The reason why is DC motors will not be able keep up with demand as load increases. So as you increase load, the PWC controller will ramp up the voltage slowly to counter act the load. Treadmill motor controls do this well but they get very hot, so a heat sink is needed attached to the heat sink the board is mounted to. The resistance is changed at the Pot to change the RPM and that is all it does. The PWC controller will do the rest in terms of load and efficiency. These kind of DC motors are well over 90% efficient. Mike  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 07-18-2007 07:22 PM                     quote: Marin Zorica Best solution is to use DC motor with gear or belt drive to film rell and which gonna be regulated with potentiometer which is moving by arm with roller, which is stretched by film moving to rell, and then potentiometer gonna regulate voltage to DC motor true some DC regulator Well then you've got an EPRAD Double MUT which is pretty easy to duplicate. Also.... Can we please see photos of the Frankenreels that go on these??? Thanks! Mark  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 07-18-2007 08:18 PM                     I'm a bit curious...With the "FrankenMUT"™...on build up...how did you deal with the tension on the system? SPECO had their LP-271-V which was very similar to the FrankenMUT™. They had to use a variable resistor to "help" the reel turn since the static resistance of the motor was too much and would but too much tension on the film. The problem with SPECO's is that one really needed to adjust the resistor depending on 6K or 2K reels and even during make up with 6K reels. The unit was short lived. Christie got the back tension thing pretty good without the need of a "helper" circuit. As to the original question...I believe they are looking for ideas on how to make a reel based transport system in lieu of a platter (i.e. tower like). DC motors can work with "Dancer Arms" to control the voltage...at the other end of the spectrum...Kinoton's method(s) using every piece of electronics known to man plus special programming...etc to have a relatively easy to use unit on the outside and looks nearly identical to its more primative cousins. You can even go for brute force things like clutches or even more scary...weighted clutches (anyone that has serviced AAFES or Kinoton FP18s will know these)...as the reel gets heavier, a belt gets pulled tigher which increases the coupling of the clutch, thereby having more torque for a heavy reel than a lighter one. Steve  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 07-18-2007 09:22 PM                     quote: Steve Guttag As to the original question...I believe they are looking for ideas on how to make a reel based transport system in lieu of a platter (i.e. tower like). That was my cue above.... the EPRAD Double MUT is pretty easy to make. Isn't the drawing in the manuals section?  |  IP: Logged Michael Moore Expert Film Handler Posts: 188 From: Dover, DE / USA Registered: Jun 2006 posted 07-19-2007 12:08 AM                        good question Steve. When I build I take the pin out that grabs the reel. It just screws out. The reel can spin freely so there is very very  low tension on the film, I do not put prints together at break neck speeds, rather i go slow, so I can control the speed of the free moving reel. The film never touches the ground. I know what you mean by the tension, and I had adjusted the resistor, but I just did not like the results. I went with the free spinning idea because it was the best solution at the time, and I have gotten so use to putting movies on the platter with it I have seen no need to change it. Now for break down, everything runs well, however there is more tension on the film then I really like so I take it very slow as well. I did not mean for this to get on the topic of the frankenMUT, but it turned out that way for a bit. As for Frankenreels they are coming next. As soon as I get done with FrankenGoldy Mike  |  IP: Logged Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 07-19-2007 02:27 AM                     quote: Michael Moore Treadmill motor controls do this well but they get very hot, so a heat sink is needed attached to the heat sink the board is mounted to. The resistance is changed at the Pot to change the RPM and that is all it does. Heat sink is the last thing on mine mind hear...is easy to put larger heat sink in combination with some fan to get more effiction cooling! Also I saw Eprad Double MUT....it has regulation true regulating transformer and pole changer on same..... Is easy to do this...one man from German film forum give me idea...to use audio power amplifier and changing them to a dc-coupled regulator by bridging a wire bridge over the coupling elko in the input and feedback and controlling the speed by using a potentiometer which is connected with the ends of the resistor to 15v and -15v of the internal power supply for the op-amps. And now out voltage can be regulated from VSS to -VSS of supply by turning the potentiometer connected to dancer arm!  |  IP: Logged Michael Moore Expert Film Handler Posts: 188 From: Dover, DE / USA Registered: Jun 2006 posted 07-19-2007 07:20 AM                        You know I can see you doing that, but it will not be a very efficient way and you would lose most of your motor efficiency as heat at the amp side. DC controls (PWM) ramp up the voltage as the load is increased, trust me it is the only way to go. You could use a full wave Bridge rectifier and filter it with some caps, and then get a large (greater then 20 AMP) variac, and then a dancer arm to control the variac. Problem again is if any load is put on the DC motor at a fast rate you will stand a chance of destroying the motor due to over heating. If I were going to make a transport (if that is what you want to do.) I would get two DC motors, to PWM controllers, and fabricate some dancer arms that will turn some small pots. The electronics from the PWM controller will do everything for you. Plus if you are going to use it for film transport heat would not be an issue, just make sure the control boards are vented and that is all, you could even use some cheap computer fans to keep them cool if you wanted to. Then all you would need to do is design your transport assay, Trust me I have experimented with DC motors more then I would like to share. I have designed drive circuits for all of my Machine shop tools, lathe milling machine, Drill press. etc. And the DC motor PWM is the most efficient, reliable and powerful for the money. The best option for these kinds of tools are VFD drive circuits with 3 phase motors, but they cost too much. But they beat a rotary inverter any day for three phase. Mike  |  IP: Logged Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 07-19-2007 08:09 AM                     I understand You Michael, but I've saw some costum and factory made system based on regular Dc controll and works very good! Also PWM controll is pretty good solution, and more effective I agree with that! What You think about some PWM kit like this ?  |  IP: Logged

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