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Old Apr 23, 2012, 03:11 PM
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I know its an old thread, but I would like to thank Gary for such nice build log!
surely better then the mpx manual that without pictures makes such a simple thing to put together a time wasting job.
thanks
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Old Apr 29, 2012, 09:41 PM
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Cheers!

I use it regularly, great bit of kit.

GB
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Old May 11, 2012, 03:20 AM
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Why don't you align the scale with 30 mm gradation over the 45 mm mark? In this way it will be much easier and practical too to read the real distance between stopper and rotation point from outside of the stopper than from inside of it that is always covered by the wing!

Good luck!
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Old May 11, 2012, 04:03 PM
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Actually, on the MPX balancer, that is the way it is(reading the distance from the back of the stops), if you follow the directions properly on assembly.

R,
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Old May 11, 2012, 04:07 PM
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Quote:
Originally Posted by JetMech2002 View Post
Does anyone have a source for these?
Mine was a gift, but a few folks got together and did a group buy and brought them all in at one time.
If I recall correctly, they were about $65 each at the time, but that was about 5 years back.
Probably more dependent on the dollar/Euro ratio than anything else, so no may be a good time to try getting one.

G/L,
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Old Aug 01, 2012, 09:50 AM
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I'm just building mine, and intend to do it exactly as per the instructions (which are not that great, I have to say). Anyway, I'm a bit curious what the reason for the accurate balancing before sticking the ruler tapes. In any case, every time you move the stops to the position for the intended CoG, you balance the beams with the counterweights. There probably is some subtle detail I'm missing here, but somehow it feels like MPX could make the instructions more understandable and easier by just making the tapes long enough to start from the end of the beam and then instructing the user to attach the supports so that the scale begins at the edge, at the 3 cm mark.

Mika
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Old Nov 11, 2012, 06:34 PM
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I've just assembled one of these and have to agree with HxA. Following the MPX instructions means that you set the CG on the inside face of the stopper which means of course that the scale is obscured once the model is on the balancer. It would be much better, as the stoppers are very prone to move on the bars, to put the 30mm scale position over the pencil mark and then you can read the CG easily on the outside of the stopper.
I wish I'd read HxA's post before I did mine as now I have to add 15mm (the width of the stopper) to the CG to be able to read the value on the outside of the stopper. Hope that makes sense.
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Old Nov 12, 2012, 05:47 PM
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I followed the instructions on my specifically, and the read IS from the outside of the stoppers....
I'm not sure if they changed the instructions between mine and yours, but I guess it could be.
I agree its much better to read from the forward end of the stoppers.

R,
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Old Feb 22, 2013, 11:16 AM
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Quote:
Originally Posted by Peper View Post
I know its an old thread, but I would like to thank Gary for such nice build log!
surely better then the mpx manual that without pictures makes such a simple thing to put together a time wasting job.
thanks
And thanks from me, I couldn't make any sense of the instructions. The pictures really help
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Old Feb 22, 2013, 11:25 AM
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No worries!

I use mine a lot. The graduated scale has lifted and needs gluing down and the balance weights often slide off on to the floor! A sliver of tape on the beam would probably fix that.

GB
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Old Sep 27, 2013, 06:47 PM
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Source for Multiplex CG machine

I ordered my Multiplex CG machine from Steve Webb models in England. http://www.stevewebb.co.uk/
Sent him funds via PayPal and it arrived in Houston two or three weeks later. USA Customs in Chicago was slow. The cost was 48 GB pounds. (about $75)
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Old Sep 27, 2013, 10:56 PM
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You will love that thing; I love mine!

R,
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Old Mar 08, 2014, 05:54 AM
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Greetings,

After having just purchased and built a MPX C of G apparatus, I realised that’s very important to follow the instructions accurately.

In particular, the equilibrium position of the scale rails must be determined with both the vertical posts and trim weights in position on the scale rails as explained in the manual as the two (vertical post and trim weight) are of different masses. The consequence of not doing this will be that your empirical C of G will be about 5 mm out.

As a general comment, it’s a good piece of kit and it minimises the error in determining the C of G. I have bought it to assist in the setting up a NAN glider and it’s made an easy job of it.

Regards & fly safe
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Old May 13, 2015, 02:16 AM
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The worst set of instructions I have ever read

It may be a useful piece of equipment, but the instructions are dire. In fact, for the UK price charged (£30), it's unacceptable.

Reading this thread shows that there are other faults: counter-weights fall off, scale lifts off.
Think hard before buying this; or be prepared to do a good deal of work for yourself.

This is a bad piece of work done by a company whose focus is not the customer.
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Old May 13, 2015, 04:46 AM
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Nice first post.
I worked hard at keeping the counter weights on mine as well. I used a single wrap of thin tape around the end of the arms the counterbalances are on. It took a lot of effort, but I managed.
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Last edited by target; May 13, 2015 at 11:17 PM.
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