[MrFlippant]

Maurizio,

I recently purchased the new Lancia LC2/85 #5. It's great car with great lines, I couldn't resist getting one.
As I normally do after a few laps out of the box, I took the magnet out and put it on my stack of slot.it magnets.
The first thing I noticed was that the magnet was either of a different material, or did not have the nickel plating that other magnets have. It was not shiny, but matte in color and rough in texture.
The next thing I noticed, hence this post, was that the polarity was reverse all the other magnets of this same type that I have.
As I said, I have them all stack up in like shapes. This one would not stack in the same orientation, but wanted to flip over to stick to the others.
I only make a point of this because the last I read about setting up the magnets under a track for oXigen use is that it was best (if not vital) to have the magnets in the correct polarity, and to determine that polarity one would refer to the shaped magnets and a diagram posted here and in the instructions.

Is polarity really an issue? If so, please be aware that you have a batch of magnets that are wrong.

Also, this magnet was very brittle. It broke into 3 pieces just from being allowed to connect to the other magnets in my stack.

Thought you should know.

 

[Abarth Mike]

Mr F,

I think as you have found out that stacking magnets during storage is bad. Individually flat side down in or on a filling cabinet etc.

I have a few broken ones also.

 

[MrFlippant]

Broken magnets don't bother me, really, since they're all just unused anyway. ;-)
Mine are all stuck to my desk lamp, and the stacks are quite short, in like shapes.
I doubt I will ever need to reinstall all the magnets in my cars such that a few broken ones will matter.

 

[Slot.it]

Approximately one year ago, prices in Nd powder skyrocketed to the point that suppliers could not quote the magnets anymore. So, in order to assure a continuous supply of goods, we changed material (to SmCo) taking care not to change the magnetic properties of the magnet itself as far as traction is concerned, and placed a large order of such magnets. Over time, Nd prices returned to 'acceptable' and we reverted to Nd magnets, as well. What you have in your hands is one of those SmCo units.

 

[MrFlippant]

Interesting.

Can you clarify if magnet polarity is important to O2 lap counting and pit lane sensing? If so, people need to be aware that this type of magnet is "upside down".

 

[Chip of FDSC]

GOOD question MrFlippant, I have wondered the same since I sometimes on occasion have a car stopping for no reason... then i push the dead car over the start/finish line and the car becomes alive again. I haven't had a chance to test the polarity. (track is not permanent)

 

[Slot.it]

Yes polarity is important, please refer to the manual 'Base description' on page 8. S pole must face the bottom of the car.
It shouldn't have any effects on car stopping, because if the N pole is up, then the car just can't sense it.

Chip, I've had a thought about your problem.
If, for whatever reason, the finish line is detected twice within (off my head) 200 ms, then the system believes the car is in pit lane, and will slow down to pit lane speed. If pit lane speed is zero, the car will stop dead. Once you push the 'dead' car cross the finish line, the system interprets it as 'end of pit lane' and makes the car go again.
Please check that you don't have two magnets under the track, that the magnet you have is not broken, that the Hall sensor is clear of any wires inside the car (also consider wires from light kit if you have it).
Try setting the speed in pit lane from PCLC to half the speed that you set in 'race' mode and see if from time to time you have a 'slow' car for one lap. I don't know PCLC well enough, but is there a way to read if a car is in pit lane? If not, please check if, when the 'dead' car crosses the finish line and becomes active again, PCLC reads a lap or not. It shouldn't as a pit lane exit should not be recorded as a finish line. It may be worth trying with our own RMS in order to get such details.

 

[Chip of FDSC]

oh man, sorry, I missed this post by 2 days so replying now. I don't like to come across as rude.

As you know, we raced on Saturday (7000 laps in total more or less with 8 cars) and we had no problems. We had an excellent time.
But to let you know, none of the above was causing my problem except maybe the hall sensor not being clear of any wires.
If my problem happens again, that will be the 1st thing I shall check.

Thanks for your help and patience Maurizio.

 

[djlutz]

Could anyone show some pictures of the magnest used, and how are placed in the track?
I would appreciate these pictures.

We're facing some lap counting issues and we followed the manual correctly.
Is just to know how the rest of O2 users are mounting the S/F track and which tricks they use (double magnets, position, etc.)

 

[Chip of FDSC]

all this info from http://www.slotforum.com/forums/index.php?...ireless-Digital

And under the track you see the magnet positioned over the little hole, perpendicular to the direction of the track above. Note, the wires next to the magnet are for the Scorpius Lane Brain LED - nothing to do with the Slot.it system. Note also the power connectors for my BLST track, the Analogue/Digital selector switch and the controller connectors for the analogue controller (when in analogue mode, the track can be used with one analogue car that drives the best racing line around the track).

The magnet needs to be positions with South facing up. The Hall effect sensor in the car can only detect one pole. Most Slot.it car magnets have South up as follows. I say most as there are a few that are polarised the other way around. Any magnet will do as long as South is up. My track is about 15mm thick and this magnet worked perfectly - it never missed a car. Obviously the car doesn't have to be 100% over the magnet as the field is quite large - and advantage of using this system. over a LED beam.

Below is the suggested configuration from Slot.it. The magnets F1, F2 and F3 work as start/finish line. P1 and P2 are the start and the end point of the pit lane area. The distance between F3 and P1 must be from 5 to 10 cm.

hope this helps you a little

 

[slotcrazy]

Just adding my pennies-worth.
My routed BLST + O2 track is not yet finished, but all the construction is done - just needs wiring up.
After talking with Maurizio, I have used Ninco button magnets. I simply drilled a hole through the MDF of the size which allowed me to press them as a "sliding fit" into the track flush with the top surface, then hot glued them from underneath and painted right over the top. Very easy....

They are more-or-less invisible and inside the wheel line of any cars. I actually used a couple stacked together for the main lap count position, a single at each end of pitlane - but could double those if needed later.

I am hoping this means never having a hall sensor not pick them up.

 

[djlutz]

Thanks for your replies CHIP of FDSC and slotcrazy,

All this information helps. finally on Saturday we found a good solution, and it's part of what you said:
I checked the polarity of the magnet as the manual says, and as you commented avobe.

What I used was 2 round Ninco magnets which increase the magnetic field; placed them under the track and the next 100 laps, no one was missed.

I will do much more tests this Thursday, lbut I'm confident now with the solution.

It could be a matter of polarity but also of magnetic field power. I'm surprised with this 15mm thickness and just a little magnet.
Now I have seen that it works, I will probably test with just one magnet, just to see the results.