SlotForum banner
1 - 19 of 19 Posts

·
Registered
Joined
·
2,885 Posts
Hi all,

I've been wondering for a while if you can open up the motors without breaking them. So now I've got a problem it's time to find out.

This SCX -RX42 started to smoke & I saw at least one of the armature wires was loose so I pulled it out with tweezers and it's still attached but I can also see another bit of wire loose inside. I can't see how to get the motor out of the plastic pod - is it possible or do I need to break it and does the motor come apart anyway?



I'm fairly ignorant about electrical things so please keep it simple.

Cheers
Chris
 

·
Registered
Joined
·
3,748 Posts
You need to lift the plastic end of the motor out of the pod, it's tight, but it will come out.
Cheapest way to get a replacement motor is to buy a complete SCX car for £10 from Pendles
 

·
Registered
Joined
·
3,748 Posts
No, you can take the motor apart by bending the little tabs that hold the can to the end bell outwards, you'll need to remove the pinion and brushes before you do this, but there seems little point as I don't think you can get a replacement armature.
 

·
Registered
Joined
·
2,885 Posts
OK, so I got it apart fairly easily and without breaking anything & here's the pics for future reference.



It hasn't burnt out and if I can get to the stray wires maybe I can stop the shorting. However, I don't have a pinion puller. The metal pinion (hidden in the pic) seems rock solid and I've tried with pliers behind it to push it off. Are there any tricks to getting it off without a puller?
 

·
Registered
Joined
·
203 Posts
To remove a brass pinion without the correct tool is fairly hard, the main issue is that you may bend or damage the motor shaft whilst trying, your best bet is to buy a Hudy pinion remover tool, you can get similar tools but if you do make sure it has a flat surface that pulls on the pinion as on few they have rounded ends!! and they can bend the pinions teeth when pulling the pinion off. This is why I suggest the Hudy as it is well made and can be purchased for about £12, but often as dear as £20.
Then you will have to replace the pinion, so another tool is required, the guy above suggested the NInco tool, this tool does both - pull and push, although not the best made, it is cheapish and does the job.

A good pinion pusher is again a Hudy pusher, but expensive, or the Slot.it or Slotting plus tools, they both pull and push, again expensive.

The pinion puller made by "Luck Bob's" is well made and can be bought for about £11.32 + £6.32 P+P, from the USA, you may get one cheaper in the UK if you can find a seller, as this will save on postage. They also make a pusher too for the same price £11.32 + £5.33 P+P, you can get combined postage if you buy both items together and save money.

Also if you fancy have a read of this, it shows how to replace a pinion without a pinion pusher tool, although it doesn't show how to remove it!:

http://slotcarillustrated.com/portal/forum...ead.php?t=29468
 

·
One petunia in a field of onions
Joined
·
6,455 Posts
The Scalex pinion/puller press isn't worth the money even at a quarter price. Believe me. I made the mistake of buying one early on in my slotting addiction.
 

·
Registered
Joined
·
3,588 Posts
QUOTE (chris99 @ 10 Apr 2012, 09:02) <{POST_SNAPBACK}>It hasn't burnt out and if I can get to the stray wires maybe I can stop the shorting. However, I don't have a pinion puller. The metal pinion (hidden in the pic) seems rock solid and I've tried with pliers behind it to push it off. Are there any tricks to getting it off without a puller?
To run properly it'll need the wire reconnected.
With a wire off it'll run slow, hot and will have difficulty starting in one position
If there is enough wire to resolder it back on where it came off go for that.
If there's not enough wire to do that, see if you can unwind one turn of the broken wire, this will give plenty of wire to reconnect.
It might be possible to do that without removing the arm from the can, although it's going to be easier to take it out.

If it's not possible to reconnect the wires you probably need a new motor (or at least a new arm).
 

·
Registered
Joined
·
2,885 Posts
QUOTE (300SLR @ 10 Apr 2012, 13:19) <{POST_SNAPBACK}>To run properly it'll need the wire reconnected.
With a wire off it'll run slow, hot and will have difficulty starting in one position
If there is enough wire to resolder it back on where it came off go for that.
If there's not enough wire to do that, see if you can unwind one turn of the broken wire, this will give plenty of wire to reconnect.
It might be possible to do that without removing the arm from the can, although it's going to be easier to take it out.

If it's not possible to reconnect the wires you probably need a new motor (or at least a new arm).
Thanks all.
Yes 300SLR, that's exactly what happened - running hot & slower & finally sent the PB into safemode. I'd superglued the stray wire onto the armature before I realised it actually should be connected somewhere. It's the first time I've had a motor problem since getting back in to slots but probably not the last.

Anyway, I can't quite get in to reconnect the broken wire, so it's a toss up between buying a puller or maybe trying a different motor - most of my cars have nylon pinions which I assume can be pulled by hand with a little heat, but the puller is on the shopping list now. For the moment, I've borrowed the motor from a £10 Nascar.

This is a new area for me but I'm moving up the learning curve. I've just got the Scalextric Audi R8 Pro Performance kit to play around and to try to understand the gearing. For the SCX should I stay with SCX motors for fit & compatibility? I see there's a 25000RPM SCX Pro motor (about £10 incl p&p) which might be fun as the car in question is a Ferrari 360, one of my most stable cars magless. Or am I wasting my money?

Chris
 

·
Rich Dumas
Joined
·
3,599 Posts
For a start you should have unhooked the motor brush springs and pulled the brushes before you removed the end bell. If a wire came loose it would have to be right where it is soldered or crimped on to the commutator. Most of the time there will not be enough slack to re-attach the wire. You have a 50-50 chance of being able to unwind the wire. Another complication is that the armature appears to have a ferrite disk attached to the commutator, that would be part of a RFI supression network and it is in the way if you need to solder the wire. If it was me and I did not expect to need a gear puller and press for anything else I would simply replace the motor. You might be able to get a free replacement with a gear on it if the motor failed when it was fairly new. In the past SCX has been very good about replacing defective motors.
 

·
Registered
Joined
·
2,885 Posts
Discussion Starter · #14 ·
QUOTE (RichD @ 10 Apr 2012, 16:23) <{POST_SNAPBACK}>. You might be able to get a free replacement with a gear on it if the motor failed when it was fairly new. In the past SCX has been very good about replacing defective motors.
Too late methinks, it looks like Tecnitoys has gone up in smoke as well (or at least into liquidation). Anyway, I've optimistically sent them message about the motor.
 

·
Registered
Joined
·
219 Posts
Chris99,
There are other reasons why the RX-42 & B, in fact all SCX motors CAN go on-the-blink. It's good that with help you got the case opened. Smoke and heat can be caused by oil in the brush holders or on the brushes themselves. I strip the motor out by removing the springs and brushes first and dropping them into cyclohexane [petrol will do] to de-oil them. Then I break out the end-bell of the motor and clean out the 'commutator???' which is the copper barrel in front of the windings. There is a groove in this which needs to be clean, I also solvent-clean the pockets where the brushes fit into. I usually use a wooden cocktail stick to scrape out any "gunk" and then a q-tip with solvent to de-oil and clean all of this. Let the goods air dry for a while to avoid a solvent fire!! Lightly oil the bearing areas at both ends of the shaft and then re-assemble.

I have NEVER seen a loose winding-wire but I have had "shreds" of braid wire get pulled up into the motor. I don't have a pinion puller either so I just use a Q-tip and solvent to wash out the back-end of the motor pod while the end-bell is removed, you can move the armature around enough to see and clean that way. I have been running SCX slot's for over six years with about 50+ cars, I have only had one motor failure. I have though used this approach to rejuvenate about six or seven tired ones.... usually works.

ATB - Bob
 

·
Registered
Joined
·
2,885 Posts
Thanks Bob, useful info for future cleaning as I'm sure I put too much oil everywhere in the early days. It's interesting to see the motor principle is pretty much as it was 30 years ago - just armature & brushes.

I'm pretty sure it's one of the armature wires come adrift and was shorting before I pulled it out, cut it & superglued it ... duh, but I can't quite get in the end enough to see the right solder points & reattach it, but I might take a flyer and see what happens.

Cheers
Chris
 

·
Ray
Joined
·
1,093 Posts
QUOTE (HighlanderSCXWW @ 13 Apr 2012, 06:36) <{POST_SNAPBACK}>Chris99,
There are other reasons why the RX-42 & B, in fact all SCX motors CAN go on-the-blink. It's good that with help you got the case opened. Smoke and heat can be caused by oil in the brush holders or on the brushes themselves. I strip the motor out by removing the springs and brushes first and dropping them into cyclohexane [petrol will do] to de-oil them. Then I break out the end-bell of the motor and clean out the 'commutator???' which is the copper barrel in front of the windings. There is a groove in this which needs to be clean, I also solvent-clean the pockets where the brushes fit into. I usually use a wooden cocktail stick to scrape out any "gunk" and then a q-tip with solvent to de-oil and clean all of this. Let the goods air dry for a while to avoid a solvent fire!! Lightly oil the bearing areas at both ends of the shaft and then re-assemble.

I have NEVER seen a loose winding-wire but I have had "shreds" of braid wire get pulled up into the motor. I don't have a pinion puller either so I just use a Q-tip and solvent to wash out the back-end of the motor pod while the end-bell is removed, you can move the armature around enough to see and clean that way. I have been running SCX slot's for over six years with about 50+ cars, I have only had one motor failure. I have though used this approach to rejuvenate about six or seven tired ones.... usually works.

ATB - Bob

Hi I have not tried this myself yet but I am told that you can carefully fill the gaps between the commie poles with superglue then polish to get any residual off which stops any damage to the brushes and give smoother running.

Ray
 

·
Registered
Joined
·
2,885 Posts
QUOTE (RichD @ 10 Apr 2012, 15:23) <{POST_SNAPBACK}>If it was me and I did not expect to need a gear puller and press for anything else I would simply replace the motor. You might be able to get a free replacement with a gear on it if the motor failed when it was fairly new. In the past SCX has been very good about replacing defective motors.
Email sent to SCXWorldwide website last Sunday- reply received from Technitoys US 2 hours later (on a Sunday!!).

Just received a replacement motor and a spare. (7 days post from the US to France).

Now that's what I call service


Thanks for the tip RichD and a big thanks to Bryan at Technitoys (long may it continue with the new owners).

SCX ROCKS!


Cheers
Chris
 

·
Living the Life&#33;
Joined
·
11,082 Posts
That is just superb customer service ........ well done SCX
 
1 - 19 of 19 Posts
Top