Lexicon -- Backlash/Lash

Strictly speaking, the accepted term for clearance between mechanical components, especially with respect to the mating teeth of a geartrain, is 'backlash'. At Dictionary.com, I found this etymology:

'backlash  1815, of machinery, from back (adj.) + lash. In metaphoric sense, it is attested from 1921.'

It seems to me that the 'back' portion of 'backlash' introduces a needless specificity to the term for many purposes. Hence, I'm inclined to simply use the word 'lash' as a catch-all term for any sort of clearance/play/slop in a mechanical relationship, even though I can find no authoritative support for that usage. Though I tend to be a stickler about correct, authoritative word usage, in this particular case I'm entirely at ease with taking the attitude, "Authority? We don't need no stinking authority!"

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Immobilizing a Lathe Spindle

My lathe has no provision for locking the spindle, and I needed to lock it so I could tap a thread in something chucked in the scroll chuck. I came up with this arrangement.

There was already an unused hole in the side of the switchbox that was the perfect size for tapping a 10-32 thread. A length of 8mm diameter rod and a 5/16" cable clamp now provide an adequate spindle lock for what I need to do.

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An Improvement -- SATURDAY, AUGUST 25, 2012

I've added a second cable clamp near the spindle to minimize lash. Here's a view of that with the chuck dismounted.

Much better.

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Addendum -- SATURDAY, NOVEMBER 24, 2012

I just discovered a little glitch. When I went to mount the lathe's four-jaw chuck, the parked spindle lock rod interfered with the jaw nuts on the back of the chuck. I had to remove the cable clamp nearest the spindle, and back the rod well away.

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Whirlpool Dishwasher Won't Drain

Odds are that the reason a dishwasher won't drain is that its drain check valve^[1] is clogged with debris. The check valve is fairly easy to get at and deal with. You'll need a No. 2 Phillips screwdriver, a set of Channellocks, and something to use for a drain pan.

Remove four screws to get the two access covers off the lower front. Set your drain pan in place, and back off the big spring-type hose clamp from the rubber elbow you'll see at the end of the check valve. Slip the rubber elbow off the end of the check valve and you'll likely have this.

A slow dribble of murky water. If the water gushes out of there freely, the check valve is not the problem, and a 'Plan B' is in order.

Patience is needed here. It took four half-fillings of that big frying pan to completely drain the dishwasher.

With the draining over with and everything cleared away, it's fairly easy to unscrew the check valve to examine it. Here's a view of the check valve out of the appliance.

That thing's inside diameter is only 10mm, so it doesn't take much to clog it. Here's what I yanked out of it with a spring hook.

I have no idea what that grotesque little object is -- it's quite hard, and it's certainly not something that we eat around here. Whatever it is, it had no business getting into the dishwasher. This is why the very first thing the user's manual tells you is, "Scrape large food soil and hard items (toothpicks or bones) from dishes."

Anyway, with the check valve and its gasket-seating surfaces cleaned, everything went back together easily. Before replacing the access panels, I ran a 'fill' and 'drain' cycle to check for leakage. All was well, so the dishwasher is good to go again.

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Note:

[1] As I understand it, the drain check valve is there so that in the event of some freakish mishap with a sewage system (as might occur in a flood, say) sewage water can't back up into the appliance. That's an excellent reason for the check valve to exist, but it does make for a somewhat constricted drainage opening.

The actual 'valve' inside the part pictured above is just a resilient flapper-valve located at the point where the diameter increases. I tried blowing through the valve in the 'check' direction, and it leaked, so how much good the valve would do if it were ever actually needed is questionable.

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A Wire Wheel Machine

I often refer to 'wire-brushing' when I write about restoring old gear. By 'wire-brushing', I seldom mean the use of these.

What I'm usually referring to is the use of this machine.

I'd be lost without the thing. It gets a lot of use here.

I built it many years ago from a 1/3 hp motor, and a ball bearing mandrel that I think I found at Canadian Tire. No one seems to make these ready-to-go; you pretty much have to construct your own to have one.

The drive ratio is approximately 2:1, so the no-load wheel speed is about 3,600 rpm.

The wheel is a fairly stiff 6" diameter one. 6" is an adequate wheel diameter, and that wheel has served me well. 8" would be better, though, and I mean to get an 8" wheel for it eventually. (When I was constructing the machine's base, I made sure to provide clearance for an 8" wheel.)

The safety police would likely taser me for that exposed v-belt drive, but there are no kids around here to worry about, and I can't be bothered making a belt enclosure for it. Different circumstances might dictate that a belt enclosure should be provided.

The one safety feature I did install was a guard for the on/off toggle switch, like so.

I fabricated that from sheet aluminum. It precludes inadvertently hitting the switch at an inopportune time.

Further to safety, don't even think about turning on a wire wheel machine without wearing eye protection. No necktie, dangling draw-cords or loose shirt sleeve cuffs, either.

Anyway, it's an indispensable item for repair and restoration work, and not difficult to construct. Google "ball bearing bench mandrel" and you'll find mandrel suppliers.

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Update -- FRIDAY, APRIL 18, 2014

I finally got an 8" wheel for the machine. Here it is installed.

The wheel is from Busy Bee; Cat. No. B355.

The wheel's bore is 32mm. It comes with a set of molded plastic bushings for adaptation to fractional inch shaft diameters, like so.

Sizes are 1/2", 5/8", 3/4", 7/8" and 1".

The wheel runs reasonably true and balanced, in spite of the hub's somewhat wobbly appearance on the mandrel. The wheel's balance is not perfect -- it generates some vibration, but it's tolerable. The wheel is rated for 4,500 rpm, so my 3,600 rpm machine is well within that. (3,600 rpm seems to be a good speed; I wouldn't run one of these wheels any faster.)

The wire ends' finish at the wheel's periphery looks a bit haphazard -- it's not uniform -- but that doesn't seem to be a problem. If anything, it imparts a 'light aggressiveness' to the wheel that's actually a good thing in operation. The wheel also moves a lot of air -- there's quite a breeze that comes off it.

One little quirk I've encountered is that the wheel occasionally has a wire break partially free, and extend about an inch. When one of those wires strikes an ungloved finger, you really feel it. You have to stop the machine and snip off the offending wire. It doesn't happen often, and I imagine the effect may cease in time as marginal wires get culled.

My machine's 1/3 hp motor has proven quite adequate for the bigger wheel, but beware of motor horsepower ratings -- not all 1/3 hp motors are created equal. I recently built another one of these machines to give to my son, and the 1/3 hp motor I used for it is not nearly as powerful as the one on my original machine -- it's easily bogged down when running the 8" wheel. I'll likely have to get a 1/2 hp motor for that machine, to be certain of adequate power.

Anyway, the Busy Bee 8" wheel is of reasonable quality for the money, and does what it's meant to do.

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Update -- Beware of Busy Bee's B355 8" Wire Wheel -- SUNDAY, JULY 6, 2014

I bought a second B355 wheel to complete the machine for my son, and the wheel is not good. It's badly imbalanced, and imparts severe vibration to the machine. It's going back to the store.

I'll update this post with the outcome of my dealings with Busy Bee over this.

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Update -- Busy Bee Gets Their Wheel Back -- TUESDAY, JULY 8, 2014

I took the wheel back to Busy Bee, along with the machine I'm building, so I could demonstrate the defect, and test an exchange wheel before taking it home. The people at Busy Bee were good enough to let me set up the machine in back for a demonstration, and we tried out all three wheels that they had in stock. All three wheels were imbalanced and worthless.

I got a refund for the wheel I had bought, and went across the street to Markham Industrial. They had a Jet wire wheel for about three times the price of Busy Bee's wheel. I bought the Jet wheel. (Jet Prod. No. 550142: 8" medium wire.)  Here's a view of it still in its package.

The wheel's appearance is much better than that of the Busy Bee equivalent. We'll see how it runs.

I can only conclude from all this that Busy Bee's B355 8" wire wheel is a poorly made piece of trash. It's only by sheer dumb luck that you may get a useable one.

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Update -- Jet Wheel And Second Machine -- SATURDAY, JULY 12, 2014

The Jet wire wheel is a decent piece of gear -- it runs fine. Here's a view of it mounted on my nearly-completed second wire wheel machine.

That machine has turned out so well, I may give it all a proper paint job.

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Drivetrain Notes -- FRIDAY, DECEMBER 21, 2018

Just to have them recorded, I thought I'd list the drivetrain specs here.

• Motor Pulley: 3" diameter.
• Mandrel Pulley: 1 1/2" diameter.
• Belt: 4L280.

Following are no load speeds with the wheel mounted, as measured with a digital photo-tachometer:

• Motor: 1,750 rpm.
• Mandrel: 3,285 rpm.

Note that mandrel speed is well short of twice motor speed. Given the 2:1 pulley diameter ratio, one would expect mandrel speed to be 3,500 rpm for a 1,750 rpm motor speed, but it's not.

There's a great deal more to V-belt drives than meets the eye. If you're interested, this article delves into some of the intricacies of calculating effective belt length, which bears on the subject of effective pulley diameter. Seemingly simple things have a way of getting a mite complicated in short order.

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A Magnifier Lamp Lens Replacement

And, "Why would a magnifier lamp's lens need to be replaced?", you may be wondering. Well, there's an easy way to ruin one, as I discovered some time ago.

I was modifying an 11/16" socket wrench to make a special spanner for removing the freewheel from a Raleigh bicycle's rear wheel, like so.

Getting the final touches done to those two lugs with a hand grinder was a delicate bit of business. I got the bright idea to employ my magnifier lamp as both a magnifier and as eye protection while I finished up the spanner. That worked out well enough that I got my spanner made, but the particles that flew from the grinding work had a rather ill effect on the under surface of the lamp's lens, like so.^[1]

I lived with that spoiled lens for quite a long time before I finally got fed up with it and decided to pursue getting a replacement. I emailed Busy Bee Tools and asked if they had replacement lenses for their model B886 lamp. They replied that they didn't, but they could ask the manufacturer if lenses could be had and for what price. It was early in February of this year that I got that ball rolling. It took quite awhile for the exercise to bear fruit, but Busy Bee did come through for me.

They now carry replacement 5" magnifier lamp lenses for $9.99 each. The P/N is P886L. They graciously absorbed the shipping charges since I'd had to wait so long for it; I just received it earlier this week.

Anyway, replacing the lens is a breeze, really. Take out the fluorescent tube and there are three screws securing both the tube clips and the lens retainers, like so.

A few minutes' work, and I finally have a nice clear view through my magnifier again.

Those who know me know that I'm no fan of the business world, but I must give credit where it's due here. Busy Bee followed through on my request for a lens in exemplary fashion. It's much appreciated.

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Note:

[1] The term 'coated optics' springs to mind here. The lens is glass and seems to be glass-hard, but the grinding fallout wrought irreparable damage to the lens' surface; I never expected that to happen. Anyway, the lesson is, "Don't use your magnifier as eye protection for grinding work."

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Extreme Salvage

My wife asked me for a bigger replacement for the screw-eye pictured below.

That new hanging flowerpot hook doesn't fit the existing eye very well at all.

I went for a scrounge where I  keep such things, and found this bit of ancient wreckage.


The top end of that was once a threaded stud -- 1/4"-20, probably. I may be pushing my luck here, but I'll see if I can restore that to a reasonable facsimile of a screw-eye.

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Here it is paint-ready.


I wire brushed it and closed up that peculiar split shank^[1] with a loop of steel wire, then filled what gap remained with five-minute epoxy to seal it. There was enough left of the shank-end that I was able to cut a vestigial M6 thread on it. If I install it with two nuts and blue threadlocker, it'll hold. I'll give it a flat black paint job, leave that to harden for a week and it'll be good to go. (I'll add a photo of it on the job when I get it installed.)

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SATURDAY, JUNE 30, 2012

All Done

Here's a photo of the finished installation.

Not too shabby at all, considering what I started with.

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Note:

[1] This may have been some sort of antenna mast standoff, originally. When we first moved into this place years ago, there was a dismantled TV antenna in the attic.

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Whirlpool Dryer -- Drum Belt Access

Applicability Note:

The following deals with a Model YLER7645JQ0 dryer. It's probably fairly typical of many dryer models.

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Access to the drum belt is pretty easy to obtain. Four screws are removed to allow the lid (w/console attached) to tip upward. (The lid is hinged at the rear.) Two screws hold the machine's front cover in place. You'll need a No. 2 Posidriv screwdriver, a No. 2 Phillips screwdriver and a 5/16" nutdriver. Unplug the dryer and proceed as follows:

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1) At either lower rear corner of the console, there's a No. 8 x 1 1/4" oval-head threading screw facing upward. (Posidriv recess.) Remove those.^[1]

2) Remove the lint filter, and at the front of the lint filter opening, remove two No. 8 x 5/8" washerhead threading screws. (Phillips recess.)

3) Pry up the front lip of the lid. The lid will pop free of two plastic catch-blocks, and will be free to tip upward and rearward on its hinges.

4) From inside near the top, remove two No. 10 x 1/2" hex washerhead screws.^[2] The front panel will be free to tip forward. Here's a view of the dryer opened up



5) Disconnect the door switch. (The connector can be quite tenacious. A small screwdriver is helpful for coaxing it apart.)

6) The front panel perches on two small steel hooks near the bottom. Support the drum with one hand while you lift away the panel with the other. (I have a 4 3/4" length of 2" x 4" that I use to prop up the drum while the front panel is off.)

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Here's a view of the drive arrangement.



Note that the tension 'idler' is not a pulley -- it's just a smooth glide that the back of the belt runs over. Force the tensioner rightward to slacken the belt so you can slip it off the motor's pulley.

Belt tension is what holds the tensioner in place. With the belt off, the tensioner comes out easily. Here's a view of the thing's glide surface.


That's quite a clever bit of engineering; one less rotating component to want lubricant or wear out.


This dryer's original belt broke almost exactly one year ago when someone overloaded the drum. The reason I'm into it again is that a peculiar symptom has cropped up -- I'll press the start button, I hear what sounds like the motor turning and its pulley squealing, but the drum doesn't turn.

The belt looks ok. I'll clean the motor's pulley and the belt with lacquer thinner and put the dryer back together. If the problem recurs, I guess I'll have to get a new belt; I really can't imagine the trouble being anything other than belt slippage at the motor's pulley.

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I should briefly mention a few things about the drum's supporting idler wheels. Here's a view of the one toward the right side of the machine above the motor.


There's another one of those lower down toward the left. There's a plastic spacer missing from the spindle of the pictured wheel. Here's what became of the spacer.


It melted when the belt broke and the dryer was on without the drum turning. By the time the high temperature limit thermostat opened up, it must have gotten ferociously hot inside the dryer.

Fortunately, the spacer isn't really needed. That wheel finds its own correct axial position on its spindle without any help from the spacer.

Note that the wheel's spindle is open-ended. (The other wheel's spindle has a support bracket at its front end.) There's a reason for that.

When you're re-installing the drum, you'll want to have only the lower support wheel to contend with while getting the drum back into place. The pictured wheel is easily removed to facilitate drum re-installation. When the drum is back in place, slip the wheel back onto its spindle and force the retainer back into its groove.

Once the drum is back on both of its support wheels, rotate the drum through one full turn, and make sure that the drum's rear seal hasn't folded under. Make corrections A/R.

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Anyway, as major appliance repair jobs go, dealing with the drum belt in these dryers is a breeze. They're a well-thought-out machine.

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Notes:

[1] Removing the two screws also makes it possible to unhook and lift the console off the machine, but for this job the console can just remain right where it is.

[2] There are two Tinnerman nuts on the lips of the front panel that the screws fasten into. The nuts are easily dislodged when you're getting the panel off its hooks. Check that the nuts are in place before reinstalling the panel.

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