What did I buy, 500 or 510?

[Cornell]

I've taken the porkchops out of both the "good" (500 upgraded to 510, which I've run and is difficult to reduce speed) and the "bad" (500 with broken speed changer, I've never run, which will be used for upgrading to Power Pro).

Both had "gunk", I'm guessing grease mixed with sawdust.

The racks look good, legs aren't splayed, there's a bit of wear on both sets of teeth.

The worm gears, on the other hand, both seem to have problems. The "good" one appears rusty. The "bad" is nice and shiny, but there's some... scrapes along the teeth at one point... I hate to use technical jargon, but they're buggered up ;-)

And the "bad" one, the plate that contacts the idler shaft, is "dented", the idler shaft ground a circle in the plate, which also shows heat discoloration.

Before cleaning...

Before cleaning. Top: "Good" one; Bottom: "Bad"

PorkchopTop_BeforeCleaning_Smaller.jpg (490.19 KiB) Viewed 2616 times

After cleaning, showing ground in circle and discoloration...

Top: Good; Bottom: Bad; Note ground in circle and heat discoloration.

PorkchopRight_AfterCleaning_Smaller.jpg (363.74 KiB) Viewed 2616 times

After cleaning, showing rusty worm gear and shiny, but buggered worm gear.

Top: Good with rusty worm gear; Bottom: Bad with shiny worm gear with buggered teeth.

PorkchopLeft_AfterCleaning_Smaller.jpg (379.79 KiB) Viewed 2616 times

So, I guess I should try to remove the rust, any suggestions?

And with what to lube the worm and rack?

And with what to lube the speed changer?

And last, the view from the end, before cleaning, the legs don't look splayed...

Before cleaning. Actually, I don't remember which is which in this photo.

PorkchopEnd_BeforeCleaning_Smaller.jpg (715.13 KiB) Viewed 2616 times

[Cornell]

Thanks JPG. So convenience is the only concern regarding lubing in fast or slow position.

[beeg]

On the ground in circle and heat discoloration, I'd say the your control sheave's bearing was frozen up. Which caused both the circle and the heat discoloration.
"Thanks JPG. So convenience is the only concern regarding lubing in fast or slow position." NO! The motor spring at slow wood be fully compressed, which wood make it near impossible to spread the coils to get to the oil hole.

[JPG]

On the ground in circle and heat discoloration, I'd say the your control sheave's bearing was frozen up. Which caused both the circle and the heat discoloration.
"Thanks JPG. So convenience is the only concern regarding lubing in fast or slow position." NO! The motor spring at slow wood be fully compressed, which wood make it near impossible to spread the coils to get to the oil hole.

That spring NOT being compressed is WHY(one of the two reasons) it is more accessible(I did NOT say 'convenient' ).

[JPG]

Those pix are helpful and appreciated, but, the 'view' needed most is the wormgear/porkchop gear teeth alignment(head on showing any tendency for the worm gear to not be in line with the 'center' of the porkchop teeth.

Did the 'blued' one have the loop attached to the button?


P.S. Does the 'bad' one have a bent worm gear?

[Cornell]

Happy Memorial Day! Let us remember those who gave their all, that we may be free.

I've attached a couple more photos.

The worm gear seems to be centered on the rack.

I note that there's a some play, side-to-side, in the racks. Just a little bit, maybe a hair, not enough for a piece of paper, in the "good" one, maybe three times as much in the bad one.

Regarding the "blued" one having the loop attached to the button. Not sure what the "button" is, but the loop from the control shaft was looped over the leaf spring on the porkchop.

As far as being bent... I put a straight edge to the sides of both, at several points. The middle four teeth all touched the straight edge. I rotated the shafts and didn't observe any wobble.

I've come upon a photo of rack, with the wear slightly off center, like both of mine. I don't know it that's a good thing ;-)

And I found a reference to using Bostik Topcoat on the porkchop, and one suggesting graphite on the speed control. Does that sound good?

I'm also thinking of taking a wire brush to the teeth in the "good" worm gear. Maybe a little 600, then 2000, grit wet-dry. Try to polish off the rust, smooth it out a bit.

[JPG]

My preference is graphite.

By bent I meant the worm gear does not have consistent spacing to the quadrant gear as the worm gear is rotated.

Both show wear that is fairly consistent with 'typical'. However 'typical' usually gets worse. The off center wear is caused by the extra force required to 'slow down'.

If the 'blued' one did have the loop over the leaf spring, the blueing was likely caused by it being missing previously and likely with a different control sheave. The 'button' is in the center race of a small bearing at the end of the control sheave hub. The loop merely prevents that button from rotating. A stuck bearing can cause that loop to pop off and the button rotate against the porkchop causing the wear and blueing.

Both show slight 'mashing' of the porkchop teeth. 'Stiffness' is caused by the wormgear and the quadrant gear teeth interfering rather than meshing properly. The 'mashing' creates an area that protrudes from the 'normal' tooth profile. Filing those down to coincide with 'normal' will relieve the stiffness. Both sides of the quadrant gear teeth may need filing.

Even though the legs do not have significant splaying, they may be bent out of alignment. Both controls show slight shifting of the quadrant to the 'left'. Again, 'typical'.

IMHO the tooth shape(straight bevel) is a weakness in the design. A full fledged worm bevel gear tooth shape would be more durable by increasing the contact area of the meshing gears. Perhaps that would also increase drag. However it would make alignment more critical, so perhaps then best compromise was used. Ramble end.

Judicious filing will relieve the stiffness. Getting it so one can turn the shaft with finger and thumb can get tedious and frustrating, but is possible. Realize the worm gear presses against the 'front' face on one quadrant gear and also presses against the 'back' side of a different tooth so one must look in from the side to determine where filing need be performed. A bent worm gear will make that near impossible.

[Cornell]

The worm gear teeth don't seem to be bent. By visual inspection, the teeth are symmetric, the same angle coming up one side as going down the other.

I lubed the porkchop and speed control with graphite, set the dial to the setting I remembered when I removed it, screwed the screws in. I noticed a small plastic strap sitting inside, laying on the motor. It must've fallen there recently. I figured out that it's supposed to be on the end of the screw that also holds the anti-rattle spring, and captures some of the wiring. So I backed out that screw and put the plastic on it and screwed it in.

Cranked it up and... still difficult from fast to slow :-(

So... live with it until the upgrade comes in ;-)

Thank you all for your kind assitance, and happy Memorial Day.

[JPG]

The worm gear teeth don't seem to be bent. By visual inspection, the teeth are symmetric, the same angle coming up one side as going down the other.

. . .

The wormgear being bent does not cause the teeth shape to change. It causes the gear to wobble.

[Cornell]

Forgive my lack of clarity... symmetric, even angles, evenly spaced. The teeth in the one are buggered up in that one area, so their angles aren't so easy to spot... It looks not like wear, but like it was dropped or scrapped on something.

As I mentioned before, rotating the worm gear provides no wobble, by eye anyway.