With the grease wicks removed (and the motor brushes if they were willing to come upwards out), it is instantly fourth dimension for us to crevice the motor open. In this entry nosotros volition acquire to take away the motor encompass together with perform the crucial line of safely removing the armature. We volition also acquire the divergence betwixt a worm together with a worm gear.
First nosotros bespeak to take away the motor cover. It is held on past times 2 screws on either side. Here you lot run into i of them. (Although the i on this machine, from the 1930s, is silver, if you lot receive got a 15-91 or 201-2 from the 1940s or ‘50s, this screw may live black.)
Begin unscrewing it--but non all the way.
Get it to most this point, hence there’s plenty infinite for the encompass to come upwards off together with and hence some. But brand certain the screw is non hence liberate that it’s going to autumn out.
Do the same amongst the screw on the other side.
Then, pick upwards the motor amongst both hands, oriented equally shown inwards the photo. (My left paw is absent because it’s belongings the camera.) Be certain non to catch the bobbin winding assembly amongst your left hand. Using your right, gently wiggle the motor encompass off. It volition probable live on at that topographic point quite tight, hence it may accept some doing. Continue wiggling it gently together with patiently together with it volition come upwards off.
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| You should live grasping the left side (but non the bobbin winder) amongst your left paw equally you lot wiggle amongst the right. |
Once it’s off, nosotros run into this. You tin give the axe laid the motor encompass aside equally nosotros won’t bespeak it for a while.
Next, plow the assembly around hence it’s similar this.
Look within the circular usage of the housing together with you lot run into this:
This is technically called a “worm.” The usage that it fits into, the fiber gear that nosotros left on the handwheel, is called the “worm gear.” People volition frequently mistakenly refer to the usage we’re looking at hither equally the “worm gear.” Be aware--if you lot utter to a technician, for example--that they’re 2 dissimilar things. The worm is shaped similar a cylinder, the worm gear is shaped like, well, a gear.
Look within the left destination of the motor. We run into the butt destination of the armature nestled inside. Don’t impact those copper wire strands; the alone house you lot ought to impact are the metallic plates indicated past times the ruddy dots inwards the photo. Those metallic plates encircle the entire armature.
You should live able to only acquire your fingertips onto those metallic plates. As you lot do, spin the armature inwards place.
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| As you lot rotate the armature... |
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| ...the worm rotates along amongst it |
As you lot spin it amongst your left hand, await within the housing. Observe that equally you lot rotate the armature, the worm also rotates. That is because it is attached to the armature shaft via what are called laid screws or grub screws. Those are screws that don’t receive got whatsoever mushroom heads, they are all shaft.
We bespeak to locate those screws. There are 2 together with they are both located on the right side of the worm. They may live obscured amongst sometime grease. I usage a Q-tip together with a pocket-size total of rubbing alcohol to dab at the right side, rotating the worm, until I tin give the axe run into a screw slot.
Don’t waste materials your fourth dimension cleaning the worm, because a) inwards a mo we’re going to receive got it out of the machine, where it’s much easier to build clean together with b) if you lot wipe a Q-tip on it also vigorously, you’ll abide by the cotton fiber all starts to unravel on the abrupt teeth of the worm, leaving you lot amongst a lot of strands you lot instantly receive got to build clean off.
Once you’ve exposed a screw slot, rotate the armature until you lot tin give the axe abide by together with let on the mo screw slot, hence that you lot know where both of them are. Now nosotros bespeak to take away both of these screws inwards a rattling specific way.
Warning: The Point of No Return
Folks, everything we’ve done upwards until instantly is reversible together with fifty-fifty if you’ve broken something, replaceable. But instantly we're most to acquire past times the Point of No Return. If you lot strip a screw spell trying to take away the worm, it’s Game Over together with your attempted repair of this motor is finished. So delight follow these instructions carefully!
First off it’s absolutely imperative that you lot usage the correctly-sized flake to stand upwards for this screw, together with that flake is a Brownells #150-4. (If you lot know of some other manufacturer's flake publish that also fits perfectly, delight allow us all know inwards the comments.)
Secondly, if you’re novel to screwdrivers together with bits you lot should read the entry most using proper hollow-ground bits.
Thirdly, you lot must receive got practiced plenty amongst screwdrivers together with slots that you lot tin give the axe consistently hold the driver completely perpendicular to the screw’s face, without letting it wander off on an angle. Trying to unscrew something at a bad angle is how you lot strip a screw.
Fourthly, you lot must receive got a screwdriver grip that lets you lot render skillful downward force, to drive into the screw.
Lastly I should dot out that if you’re a lefty, you lot may abide by this difficult.
If you’re all set, let’s proceed.
Loosening the Worm
Using your left hand, rotate the armature to a seat where you lot tin give the axe access i of the screws inwards the worm.
Place your screwdriver into the slot, together with press it into the screw firmly. Keep your left paw on the armature to foreclose it from rotating around, which would mess upwards your connectedness amongst the screw. Keep the screwdriver grip dead perpendicular amongst the screw face.
Here’s a tip: You don’t bespeak to unscrew it all the way, only loosen it 3 half-turns from its master position. (That’s technically 1.5 total turns, but I abide by it easier to count out 3 half-turns spell doing it.) That volition live plenty to take away the armature. Loosen both screws inwards this manner.
Removing the Armature
Once each of the 2 screws inwards the worm receive got been loosened 3 half-turns, amongst your left paw you lot should instantly live able to slide the armature out of the housing.
However: On a pocket-size percent of machines, you lot may abide by the armature’s metallic plates--those same plates you’re grabbing amongst your fingers--are beingness "blocked in" past times the dark enamal wrapping on the plain windings. If that’s the case, create NOT examine to strength it out; move out me a comment together with I’ll gear upwards a divide entry for what to do.
If you’ve gotten the armature out, congratulations. Remember to concur it alone past times the metallic plates equally you lot grip it. (You tin give the axe safely concur it from the shaft too, though it’s probable quite greasy.)
Once you’ve got the armature out, inspect the base of operations of the shaft closely; you lot should run into a sparse fiber washer on it, equally seen below.
If you lot don’t run into the washer, banking concern check i time again to brand certain it’s non only stuck to the base of operations of the shaft, perchance nether a sparse layer of grease. If it’s definitely non there, await into the motor, equally inwards the photograph below; the washer may live stuck to the bearing.
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| I tin give the axe run into the shininess of the brass bearing, hence there's no washer stuck here. |
If you lot abide by the washer stuck to the bearing, pluck it off carefully amongst some tweezers, together with stick it onto the armature shaft, where it belongs, for safekeeping.
The armature tin give the axe render some of import clues equally to the wellness of the motor, but we’ll acquire to that later. Although I would unremarkably build clean it at this stage, I’m going to shuffle the lodge a flake equally I’m certain you’re eager to run into if the wiring on your motor is salvageable, which is an entry or 2 away. So laid the armature aside for now, preferably wrapped inwards plastic to hold dust off of it together with to hold whatsoever grease on it from migrating around your move area. Be certain non to lose that fiber washer!
Now that you’ve removed the armature, the worm may receive got fallen from betwixt the 2 bearings it spins betwixt (or it may live held inwards house past times all of the sometime grease).
Either way, you lot tin give the axe line it out amongst a twosome of tweezers or angled forceps, my tool of choice. The tolerance--the infinite betwixt the worm together with the bearings--is frequently quite tight, hence you lot volition alone live able to take away it past times pulling it direct out, equally opposed to at an angle. That’s why I similar the precision the angled forceps afford.
Once you’ve gotten the worm out, you lot tin give the axe build clean it off using rubbing alcohol. Don’t forget to destination removing the laid screws together with build clean those equally well. Then laid them aside inwards a security place.
Lastly, you lot tin give the axe instantly build clean all of the old, nasty grease out from nether where the worm was mounted.
To build clean it, I usage a Q-tip dabbed amongst rubbing alcohol, because amongst the armature removed, at that topographic point is no run a peril whatsoever alcohol volition run downward the shaft together with into the motor.
Go on to Part 12: Detaching the Field Core
