01-04-2003, 12:23 PM
|
TinyRC Pro
|
|
Join Date: Jan 2003
Location: Tulsa, OK
Posts: 33
|
|
Rare Earth Magnets . . . hype?
I heard about the mod to replace the steering magnet with rare earth magnets from Radio Shack, so I thought I'd give it a try on one of my bits.
Once I got the old magnet out, it didn't seem much weaker than the rare earth one. Well . . . I've got a gauss meter at work, so I thought I'd check them out.
Stock magnet: 3,550 gauss
Rare Earth magnet: 3,700 gauss
The stock one is pretty strong already and I don't think the rare earth makes that big of a difference. I won't be wasting anymore time replacing magnets in the future.
Just my .02
|
01-04-2003, 02:25 PM
|
TinyRC Pro
|
|
Join Date: Nov 2002
Location: Winnipeg
Posts: 31
|
|
Magnets
Wow thats really interesting!
Is it possible, however, that some magnets may not be as strong as others? Maybe you got lucky and got a strong steering magnet...
Would be interesting to see other people doing the same experiment you did, and see if the stock magnets are all the same.
As for the numbers, it's been a while since I studied magnets in high school, so is that a big difference between the two numbers? What would say, a cheap fridge magnet be?
Last edited by Dys70pia; 01-04-2003 at 02:27 PM.
|
01-04-2003, 05:42 PM
|
TinyRC Pro
|
|
Join Date: Jan 2003
Location: Tulsa, OK
Posts: 33
|
|
Okay, based on your questions, I went around the house with my tester and here's what I found.
Flimsy fridge magnets: about 250-300 gauss
Solid fridge magnets: about 350-400 gauss
Tool retriever magnet from my toolbox: about 1,000 gauss
Rare earth magnet that my company makes: 3,800 gauss
Rare earth from Radio shack: 3,700
Stock bit steering magnet: 3,550 (I have now tested more than one and they are all pretty close)
Going by these numbers, I'd have to say that the stock bit magnets are in fact rare earth magnets already. Probably not as good quality as Radio Shacks, but good enough to turn the little cars anyway.
|
01-04-2003, 06:36 PM
|
TinyRC Pro
|
|
Join Date: Dec 2002
Location: Knoxville
Posts: 60
|
|
no there aer real differences. with rem the wheels can turn at standstill on most surfaces, before it had to be moving pretty well to turn.
__________________
My Fairlady Z:
-------------------------
*rare earth*
---------------------------
|
01-04-2003, 08:07 PM
|
TinyRC Pro
|
|
Join Date: Nov 2002
Location: Winnipeg
Posts: 31
|
|
cool
So the stock magnet is pretty stong then... I guess people are finding that the extra 150 gauss really does make a difference... I suppose the tiny changes are sorta trivial; but so are many of the antenna mods for increasing reception.
Perhaps the extra 150 gauss are somehow important when youve got the two electromagnets on either side of it... especially when the power through the magnets are boosted with a dual cell mod....
I guess everyones individual experience is more important than numbers... I'm too lazy to go through all the math anyway... =P
|
01-04-2003, 09:44 PM
|
|
I are smart....
|
|
Join Date: Dec 2002
Location: Boston, MA
Posts: 393
|
|
I bought a set of magnets at RS and haven't even put them on any of the cars I have. I figured that if the car is turning fine, why bother. I just put it in my box of crap just in case I would need it.
|
01-05-2003, 08:13 AM
|
Bit Surgeon
|
|
Join Date: Sep 2002
Posts: 216
|
|
I had noticed similar results too, though I didn't have a gauss meter. I tried to see how many sheets of paper each magnet would hold to a refrigerator and found they held the same number (I forget the number of sheets).
I wonder if the improved steering that I and others have reported is in fact due to the original magnet not being properly centered? It seems like such a tiny change in actual magnetic strength wouldn't be noticeable.
I traced one improvement in steering to the fact that while changing a steering magnet I happened to swap the two micro springs installed on my steering knuckles; apparently they were slightly different lengths and after I swapped them they worked better on the other side.
Interesting findings Krabill.
|
01-05-2003, 10:09 AM
|
TinyRC Pro
|
|
Join Date: Jan 2003
Location: Tulsa, OK
Posts: 33
|
|
Yeah, it's only about a 4% difference, which is actually an acceptable tolerance when making magnets. Anything over 3,000 gauss is incredibly strong. The magnets we make are all 1" x 2" x 2" and even the ones that only come out to about 3,200 gauss are nearly impossible to remove from a solid steel object (like the back of the forklift ).
I would attribute better steering to something else, like accidently bending the spring more, or getting the magnet exactly centered, or just paying more attention when you assemble it than the original factory did.
|
01-05-2003, 11:56 AM
|
|
I agree, this REM stuff was probably a good idea, assuming the use of wimpy magnets being used in the first place, but the engineers behind these marvels probably pulled every trick they know (like this one) just to make them work in the first place!
|
01-05-2003, 08:22 PM
|
|
Registered User
|
|
Join Date: Dec 2002
Location: Minnesota, USA
Posts: 137
|
|
I agree that the stock magnet in my Rally Racer/Shen clone was very strong. But the steering on the car was definately not as good as my MicroSizers was.
I changed to the RS Rare Earth Magnets and it was a total night-and-day difference! The steering and control went from OK to TERRIFIC in 10 minutes time (the time it took me to change them out). Handling and steering is extremely predictable and precise now. All of my Bits/clones will get Rare Earth magnets.
As with anything, your results may vary. If I have learned one thing in this hobby it's that the construction and manufacture of these cars is very inconsistant, even within the same brand.
Just my personal observations.
John
__________________
"It takes a Mopar to catch a Mopar!" - Vanishing Point
|
01-06-2003, 11:13 AM
|
|
I have heard the same thing from others too.
I guess for the low price of those magnets I'd be crazy not to at least try 'em.
|
01-06-2003, 12:52 PM
|
|
Hulk smash!
|
|
Join Date: Jul 2002
Posts: 2,193
|
|
Thanks for the investigative work Krabill, I've added the info to the Bit FAQ.
|
01-06-2003, 03:17 PM
|
TinyRC Pro
|
|
Join Date: Dec 2002
Posts: 39
|
|
Are you measuring the rare earth magnets stacked together? Or is there even a difference between 1 magnet and two of them together?
|
01-06-2003, 04:32 PM
|
TinyRC Pro
|
|
Join Date: Jan 2003
Location: Tulsa, OK
Posts: 33
|
|
When I took the reading, I had (2) of them stacked together, but I'll take the meter home again tonight and do just one for ya and post my findings later this evening.
|
01-06-2003, 09:53 PM
|
TinyRC Pro
|
|
Join Date: Jan 2003
Location: Tulsa, OK
Posts: 33
|
|
Okay, as promised here are my findings tonight.
I have (4) bit clones from Walgreens that I opened up all for the sake of science.
Car 1 - stock magnet: 3,350 gauss
Car 2 - stock magnet: 3,550 gauss
Car 3 - stock magnet: 3,560 gauss
Car 4 - (2) r.e. from RS: 3,450 gauss
Stock magnet taken out of Car 4: 3,550 gauss (I guess I should have left it in, huh?)
Remaining r.e. from RS #1: 2,600 gauss
Remaining r.e. from RS #2: 2,600 gauss
Remaining r.e. from RS stacked together: 3,700 gauss
All stock magnets (which are in fact rare earth to begin with) are within 6% of each other. The (2) I bought from Radio Shack are more than 7% different.
This leads me to believe that the stock rare earth magnets are of better quality and a better bet to getting good steering than any magnet bought at Radio Shack since you probably don't own a gauss meter to pick the very best ones, and even if you did, a couple hundred gauss will not make a noticable difference in steering. I really don't know what to tell those of you who insist you have noticed a difference, because as you can see, it is pretty much an impossibility. :shrug:
|
Thread Tools |
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -5. The time now is 05:34 PM.
|
|