Hi,
Anyone have any experience with using alternative methods to fix motors to chassis (rather than soldering)?.
Soldering seems great for strenght and heat conductivity, but apparently even a short period of heat reduces the effectiveness of the magnets. And expoxy glue does not seem strong enough?
Fixing motors to chassis
Re: Fixing motors to chassis
Hi Jacco
Drag racers have a lot of success with screwing the motor in......even with G20's!
It is actually mandatory for some of the magnets they are starting to use.
The method that Parma uses with their ready to runs is absoloutely useless for any longevity.
Best bet would be to secuerly solder a bracket, to screw into the motor, to the chassis, can end and endbell ends of motor for circuit work (probably get away with just the can end for drag cars).
See Paul at Western Sydney Model Car Raceway for more info on WRP, DRS, and other drag products.
Also, years ago, i remember you could buy a chassis with the motor can already securely attached to the chassis. You had to build the motor while it was already in the car.
Maybe you could experiment with that kinda thing. Solder the motor in normally, without the magnets in, then reassemble the motor.
good luck
and let us know how it goes!
Drag racers have a lot of success with screwing the motor in......even with G20's!
It is actually mandatory for some of the magnets they are starting to use.
The method that Parma uses with their ready to runs is absoloutely useless for any longevity.
Best bet would be to secuerly solder a bracket, to screw into the motor, to the chassis, can end and endbell ends of motor for circuit work (probably get away with just the can end for drag cars).
See Paul at Western Sydney Model Car Raceway for more info on WRP, DRS, and other drag products.
Also, years ago, i remember you could buy a chassis with the motor can already securely attached to the chassis. You had to build the motor while it was already in the car.
Maybe you could experiment with that kinda thing. Solder the motor in normally, without the magnets in, then reassemble the motor.
good luck
and let us know how it goes!
Petrol is for cleaning parts
Alcohol is for drinking
Nitro is for racing
Slotcars are for going VERY quick!
Alcohol is for drinking
Nitro is for racing
Slotcars are for going VERY quick!
Re: Fixing motors to chassis
Thanks Chadley. Yes indeed, it's mainly the flexi chassis that are the problem (GT1, Utes and V8 at HSC). Every other class seem to mount the motor. I reckon every time you solder the motor, you lose 5-10% of the magnet strength (and power). I pre-tin the surfaces then clamp the motor on the chassis. I turn my heat up on the soldering iron so I can get away with a shorter soldering period. Then quickly cool the motor afterwards. Other say that it's better to turn the temp down, but I found that it takes to long and it really heats up the motor for longer.
Dismantling the motor beforehand may be a good option. Doesn't work for Falcon motors though...
cheers,
jacco
Dismantling the motor beforehand may be a good option. Doesn't work for Falcon motors though...
cheers,
jacco
Re: Fixing motors to chassis
Jacco soldering motors in is best. With the Flexi's ,, S16D etc they take such a pounding screws come loose .
Temperaturs under 200* C won't have any effect on the magnets.
Why don't you ask me when at HSC and i will tell you what you need to know.???????
Sounds like you need some soldering lessons and if you use the right epoxy absolutely no way will your magnets come loose.
Temperaturs under 200* C won't have any effect on the magnets.
Why don't you ask me when at HSC and i will tell you what you need to know.???????
Sounds like you need some soldering lessons and if you use the right epoxy absolutely no way will your magnets come loose.
Re: Fixing motors to chassis
Yes Jacco !!
As you are I am sure aware,..Many of us are only Too Happy to help.
Always worth learning to Solder Extremely Well !!
Good Prep', Good Flux and a Good Damn Hot Iron, (so the work can be completed Quickly Without a lot of Heat 'Soak'), is the Go.
Although I Do tend to agree with you re the Magnets, it IS often simply the easiest most efficient method and Has been done for Years, even way back with Only Ceramic Magnets.
Trying to keep a Good stable gear mesh on an anglewinder, with a pretty decent 'pokey' motor IS difficult. It Can work in classes like the Plafit's, partly because of the mounting method AND the fact the Motors have Bugger All Torque!!
Cheers,
Stewie
As you are I am sure aware,..Many of us are only Too Happy to help.
Always worth learning to Solder Extremely Well !!
Good Prep', Good Flux and a Good Damn Hot Iron, (so the work can be completed Quickly Without a lot of Heat 'Soak'), is the Go.
Although I Do tend to agree with you re the Magnets, it IS often simply the easiest most efficient method and Has been done for Years, even way back with Only Ceramic Magnets.
Trying to keep a Good stable gear mesh on an anglewinder, with a pretty decent 'pokey' motor IS difficult. It Can work in classes like the Plafit's, partly because of the mounting method AND the fact the Motors have Bugger All Torque!!
Cheers,
Stewie
Re: Fixing motors to chassis
Even ceramic magnets are not to effected by the heat from a soldering iron, the magnets in falcon motors are neo's and are more likely to be effected by soldering you just have to keep the time you have the iron on the motor to a minimum. Nice hot iron and good flux will help keep the process to a minimum
Always the Hydrant, Never the Dog
Re: Fixing motors to chassis
OK then,..just to Help on the Magnet and Heat thing a bit,..lol
All magnetic materials are at all times as fully magnetized as their thermal state permits.
Prior to "magnetization" their magnetic domains arrange randomly to minimize their internal (and external) energy state.
Magnetization rotates magnetic domains into common alignment. Permanent magnets retain this alignment to a degree, depending on their geometry, chemistry and anisotropy mechanisms. (Consider anisotropy here as all those things that resist a magnetizing force, and thus a demagnetizing force as well).
Magnetic domains in the center of a magnet support each other, but those domains closer to the sides, ends and edges of the geometry have less support, and some are reversed by the magnet's own external field, which has a polarity opposite to the internal field.
When heat is applied, longer electron orbits cause all domains to weaken to a degree, and those with more exposure to the external field (or are weaker for some other reason) will also reverse.
Invariably, magnet manufacturers further Heat Treat the Various materials during manufacture, to Better suit it's designed operating environment, through a process known as 'Thermal Knockdown'.
Thermal knockdown is the process of raising a magnet’s temperature to the temperature expected in the application so any impending change will have occurred prior to installation of the magnet. At elevated temperatures, the demagnetizing force for isolated magnets will be its own self demagnetizing force, so thermal stabilization is invariably done in a fixture that reproduces the operating 'permeance coefficient',..(gotta Love that term eh!!??), to avoid loss of useful and stable flux levels.
A magnet is heat stabilized by exposing it to elevated temperatures for a specified amount of time.
This is done to prepare for the irreversible losses of magnetism that most magnets experience when exposed to elevated temperatures.
You can think of heat stabilization as insurance against elevated temperatures.
There are two types of magnetic losses when a magnet is heated to elevated temperatures: reversible & irreversible.
Reversible magnetic loss is the weakening of a magnet when heated to elevated temperatures. It is called reversible, because the magnet recovers this portion fully upon returning to room temperature.
Irreversible magnetic loss also occurs at elevated temperatures but is not recovered upon return to room temperature. It is a permanent loss, unless the magnet is sent back for remagnetization. This is a one-time-only effect.
An example: A given magnet produces 1000 Gauss at room temperature. It is baked at 200 °C (400 °F). While at that temperature, it only produces 850 Gauss. Upon return to room temperature you measure it and find it now only produces 950 Gauss. The missing 50 Gauss is the irreversible loss. If the magnet was returned to 200 °C, it will still produce 850 Gauss. If it was taken to a higher temperature then it would lose more output.
The amount of irreversible loss depends on a lot of factors, including the type of magnetic material, the shape of the magnet, the temperature it experiences and the amount of time it sees that temperature!!
Ceramic Magnets are definitely the most 'delicate' in that regard, as depending on the material used, their 'absolute', or Curie point, can be as low as 200 deg' C, but usually around 300 to 350 deg' C and often do Not exhibit the same kinds of Natural 'Anisotropy' as Rare Earth materials.
All magnetic materials follow a fairly Linear curve of megnetic coercivity as the temperature rises and falls, in Fact Most Magnets get noticeably Stronger when cold! (Ceramic magnets being the exception here!),..in Fact it is THIS fact, that has made Neo-Dymium, style 'Martixes', such as that developed by AC Delco for use as Starter Motors, such a Great thing for the Auto Industry. Want some Cranking Power in The Snow !!???,..lol
Neo type materials exhibit even Greater Coercivity at Low tepmeratures than Cobalt, but unfortunately, do Not exhibit similar stability as Cobalt at Higher temperatures,..Mind you the Thing with Neo's, is that their Inherent Heat stability can be Extremely High, so even though they Lose coercivity at elevated temperatures, they invariably Return, (without Loss), unless taken Past their Curie point.
Hey!,..I kinda figured You'd Know all this Jacco !!!,..
I guess, when you consider that Open Motors have often become hot enough to Melt Lead Wires Off, allow Pinions to spin, magnet holding epoxy to soften, let alone complete de-stabilisation and Frying of Cummutators and armarures!!!,..lol,..the Heat applied when Soldering in a Motor, when well Prepared with Good Flux and a Damn Hot Iron, is in Fact Rather 'Breif' !! and if Done Quickly and 'Deftly', is Less of a Problem than one would Imagine.
So, as noted from the Above, Ceramic magnet Motors should be Treated with Far Greater Care 'Heat Wise', (they also Don't like being Dropped!) and I would Venture, would 'Benefit' from Regular and reliable Re-Magnetisation, to maintain Optimal performance !!
All magnetic materials are at all times as fully magnetized as their thermal state permits.
Prior to "magnetization" their magnetic domains arrange randomly to minimize their internal (and external) energy state.
Magnetization rotates magnetic domains into common alignment. Permanent magnets retain this alignment to a degree, depending on their geometry, chemistry and anisotropy mechanisms. (Consider anisotropy here as all those things that resist a magnetizing force, and thus a demagnetizing force as well).
Magnetic domains in the center of a magnet support each other, but those domains closer to the sides, ends and edges of the geometry have less support, and some are reversed by the magnet's own external field, which has a polarity opposite to the internal field.
When heat is applied, longer electron orbits cause all domains to weaken to a degree, and those with more exposure to the external field (or are weaker for some other reason) will also reverse.
Invariably, magnet manufacturers further Heat Treat the Various materials during manufacture, to Better suit it's designed operating environment, through a process known as 'Thermal Knockdown'.
Thermal knockdown is the process of raising a magnet’s temperature to the temperature expected in the application so any impending change will have occurred prior to installation of the magnet. At elevated temperatures, the demagnetizing force for isolated magnets will be its own self demagnetizing force, so thermal stabilization is invariably done in a fixture that reproduces the operating 'permeance coefficient',..(gotta Love that term eh!!??), to avoid loss of useful and stable flux levels.
A magnet is heat stabilized by exposing it to elevated temperatures for a specified amount of time.
This is done to prepare for the irreversible losses of magnetism that most magnets experience when exposed to elevated temperatures.
You can think of heat stabilization as insurance against elevated temperatures.
There are two types of magnetic losses when a magnet is heated to elevated temperatures: reversible & irreversible.
Reversible magnetic loss is the weakening of a magnet when heated to elevated temperatures. It is called reversible, because the magnet recovers this portion fully upon returning to room temperature.
Irreversible magnetic loss also occurs at elevated temperatures but is not recovered upon return to room temperature. It is a permanent loss, unless the magnet is sent back for remagnetization. This is a one-time-only effect.
An example: A given magnet produces 1000 Gauss at room temperature. It is baked at 200 °C (400 °F). While at that temperature, it only produces 850 Gauss. Upon return to room temperature you measure it and find it now only produces 950 Gauss. The missing 50 Gauss is the irreversible loss. If the magnet was returned to 200 °C, it will still produce 850 Gauss. If it was taken to a higher temperature then it would lose more output.
The amount of irreversible loss depends on a lot of factors, including the type of magnetic material, the shape of the magnet, the temperature it experiences and the amount of time it sees that temperature!!
Ceramic Magnets are definitely the most 'delicate' in that regard, as depending on the material used, their 'absolute', or Curie point, can be as low as 200 deg' C, but usually around 300 to 350 deg' C and often do Not exhibit the same kinds of Natural 'Anisotropy' as Rare Earth materials.
All magnetic materials follow a fairly Linear curve of megnetic coercivity as the temperature rises and falls, in Fact Most Magnets get noticeably Stronger when cold! (Ceramic magnets being the exception here!),..in Fact it is THIS fact, that has made Neo-Dymium, style 'Martixes', such as that developed by AC Delco for use as Starter Motors, such a Great thing for the Auto Industry. Want some Cranking Power in The Snow !!???,..lol
Neo type materials exhibit even Greater Coercivity at Low tepmeratures than Cobalt, but unfortunately, do Not exhibit similar stability as Cobalt at Higher temperatures,..Mind you the Thing with Neo's, is that their Inherent Heat stability can be Extremely High, so even though they Lose coercivity at elevated temperatures, they invariably Return, (without Loss), unless taken Past their Curie point.
Hey!,..I kinda figured You'd Know all this Jacco !!!,..
I guess, when you consider that Open Motors have often become hot enough to Melt Lead Wires Off, allow Pinions to spin, magnet holding epoxy to soften, let alone complete de-stabilisation and Frying of Cummutators and armarures!!!,..lol,..the Heat applied when Soldering in a Motor, when well Prepared with Good Flux and a Damn Hot Iron, is in Fact Rather 'Breif' !! and if Done Quickly and 'Deftly', is Less of a Problem than one would Imagine.
So, as noted from the Above, Ceramic magnet Motors should be Treated with Far Greater Care 'Heat Wise', (they also Don't like being Dropped!) and I would Venture, would 'Benefit' from Regular and reliable Re-Magnetisation, to maintain Optimal performance !!