Magnalyser vs Facts Machine v3 ???
 

I'm thinking about picking up a rotor meter. Do I need it? Well no, but I want one, lol. Anyway, I have a motolyser II so I can use a magnalyser, but the facts machine v3 is $100 cheaper. Has anyone compared these 2? Are either of them even accurate enough to give you reliable readings or is it more for measuring loss on your own stuff over time? Pretty much I want to make sure that if I buy one of these that the $200-$300 I spend will actually give me peace of mind when I check a rotor.

And for a few dollar you have an analogue HALL sensor you can connect to a voltmeter.

Yes, but my understanding of what you made in another thread was that it was just for comparison. I want to see how far off a rotor has fallen from it's reputed 1700+ manufacturer claim. I guess to say it frankly, I want to see the actual reading and not a relative reading. But if you can build that and want to share, sure, I'll give it a go.

I think most RC rotor meters as mine are just to show you a number to compare with others or the degeneration of one. I made it because with stock racing people were mounting other rotors with more strength and measuring some real stock rotors you know in what window they have to be. And even then the best of the real stock rotors did show a slight better performance so you can select rotors as well.

If you want a real number then you have to get a professional magnetic gauge meter, but they are expensive.

The "problem" is if you've already ran the motor a few times, the initial heat will knock down the strength a measurable amount. I've talked with Troy from fantom a bunch, and you'll lose something like 20-50 points from brand new to 2-3 runs of normal heat.

Also just because it would read 1702 at fantom it wont necessarily read the same on a facts machine you buy. The important part is measuring it before you run it and after say 5 runs. Then you'll have some numbers to compare to later. The advantage to a premade tool is it should be much more accurate and precise than hooking up a sensor to a multi meter and most hobbyist tuners I know use the fantom tools because they're cheaper and have been around longer. At least for the rotor tool since its been the only one until recently.

So are you saying that the magnalyser or the facts machine v3 do not give the actual numbers? This is what I want to find out, whether either of those products is accurate and if the magnalyser is worth the extra $100. But if neither are accurate, then I don't want to waste my money.

They're accurate at comparing different rotors to one another. I've had both and kept the Facts machine. Five of us tried on three different Motolyser II's to get the magnalyser to work and never could. I finally gave up on it and use it as a $200 paperweight.

So the consensus is that it will be no good for rotors I already have, or at least I can't tell if my old rotors are bad unless I have a new rotor to compare them to. I do have a brand new rotor that has only been spun up to measure the timing, but I was planning on running that on the track tonight. If I decide to buy the Fantom or build one of Roelof design from another thread, I need to buy a new rotor as well. Can I assume that the rotor manufacturer doesn't matter? I can compare strength at least from different manufactures?

Interesting thing to note... I finally got to run my new rotor for an R1 motor. I put it on my motolyser before running to initially set the timing and noted the amp draw and the timing. After running the motor 4-5 times and putting it back on my motolyser I noticed that the amp draw had gone down for that timing. It wasn't much, went down from 3.1 amps to 2.85 amps. My presumption because of the posts above is it did this due to loss of strength of the rotor.

Keep in mind that after running also bearings and the endbell will be seated well.

I was able to pick up a used facts machine v3. I measured all my rotors with it. Some interesting results. I have 2 trinity copper rotors, one that came in my slot machine and one that came in my certified X factor. The X factor is a couple of years old. Both of those rotors measured extremely close, within a few points. I also have a certified red rotor that measures about 20 pts higher than the copper rotors.

Now for the interesting one. I have both a short rotor r1 and a long rotor. The short rotor is considerably stronger than the long rotor. The short rotor is comparable to my trinity copper rotors while the long rotor is about 50 pts less. The long rotor is only a few weeks old and only has a handful of runs on it.

My take on this is get the Fantom V3 and call it a day. I use mine to see what my rotors are when new and periodically check them during rebuilds to see how much strength they may lose over time. I also use my findings to compare rotors of other manufacturers to gauge how it may perform in their motors. High rpm motors normally have weaker rotors compared to Torque motors. You can have faith in your purchase to know that the readings are accurate. I have been using the Fantom rotor checker since their V1 edition. It hasn’t disappointed me ever.

I have both the Motolyser and fact’s machine. There seems to be a 30 pint difference between the two. I defer to the maglayser since I can check motors and rotors

Does the Facts Machine read higher? I just measured a brand new rotor today that came from Trinity and was supposed to be 1703. I think it read around 1725, which is right about where all my other copper rotors measure, even after a couple of seasons worth of use.

I adjusted my meter to about 1000 on a scale of 2000 max with the use of a stock rotor. Testing some rotors on the club they fell in a window of about 990 and 1010, one guy with the fastest motor on the track did measure almost 1020 on the rotor.