Waxed Paper 'Washers' For Finish Protection

If you attach anything securely to a painted or varnished surface, the attached thing is likely to 'weld' itself to the surface tenaciously, no matter how well hardened the finished surface appears to be. Future removal of the attached thing will result in damage to the surface underneath. That may or may not matter to you, but if you'd rather preclude such damage, install waxed paper 'washers' at the interface of the attached thing, and the painted or varnished surface.

I recently removed the mechanic's vise from my workbench, so I could refinish the workbench's hardboard surface with polyurethane. Where the vise base's mounting washers had been in contact with the bench, the washers had bonded themselves to the bench with a vengeance. The washers came away with great shards of hardboard stuck to them, like so.

I filled in the damaged spots on the benchtop, refinished the bench's surface and cut three waxed paper washers for the reinstallation of the vise.

And here we are with the vise's base bolted back in place.

The reason for placing washers underneath the vise's swivel-base mounting ears is to preclude breakage of  the swivel-base casting. Tightening down a cast swivel base directly onto a benchtop's surface is unwise -- irregularities in the surface, and/or the casting, can result in stresses that may break the casting. I've seen it happen. The washers serve to concentrate all the attachment force directly at the ears, isolating the rest of the casting from untoward forces.

# # #

FEEDBACK

# # #

On Salvaging Old Gear

On the face of it, salvaging old gear of any kind seems like a paying proposition. Retail prices of anything new these days are sky high, and are unlikely to ever come down. But are there really savings to be had in salvage?

Much as I'd like there to be, and much as this blog has often featured salvage projects as subject matter, I'm not so sure that salvage effort is always, or even often, worthwhile.

Over my years of servicing laser and impact printers, and working closely with printer subassembly remanufacturing operations, it dawned on me that there seems to be nothing quite like factory 'newness'. No matter how meticulously an old mechanism is refurbished, its service life and reliability are unlikely to equal those of new replacements.

Anyway, for want of anything better to do, I thought I'd refurbish an old water supply shut-off valve, and test it out to see if it could still be trusted to give leak-free service. Here's a view of the valve.

It's a common 1/2" copper pipe to 3/8" compression fitting shut-off valve, as is typically installed for a faucet's water supply. This one appears to have been installed by a DIYer -- there's evidence of some sort of sealant having been applied to places where there ought to be no need for sealant. DIYers are notorious for gratuitous application of sealant.

I'll clean it up nicely, and devise a test fixture. If it doesn't leak at its valve stem when fully opened, I'll consider my refurbishment to have been a success.

Following are a few noteworthy points:

Washer

The washer in this type of valve is not replaceable. Water supply shut-off valves are so seldom closed that washer wear is not an issue. An embrittled, cracked washer would spell the end of a valve's usefulness, unless one wanted to undertake the machining necessary to make the washer replaceable.

The Valve Seat

Like the washer, the valve seat is not replaceable. A corroded valve seat (unlikely) might be salvageable by reaming and/or burnishing with valve-grinding compound. See this post.


Valve Stem

The valve stem ought to be cleaned with fine steel wool prior to removal of the gland nut and seal. One wants nothing to abrade the lip of the valve stem's seal as the seal is removed.

The 1/2" Copper Pipe Socket

I've been meaning to acquire a 5/8" reamer to help me salvage 1/2" copper pipe fittings, but the price has been scaring me off. Meanwhile, I've been making do with an X-Acto knife and steel wool.

The socket must be clean, and must easily accept a pipe end to the full depth of the socket.

The Valve Stem Seal

There are two parts to the seal -- a thrust washer, and the ring-seal itself.

The thrust washer is concave; the concave side goes outboard. The ring-seal is asymmetrical face-to-face; note its orientation as you remove it.

The ring-seal must be resilient and undamaged, else the valve is a write-off. The seal pictured here looks a bit distorted on one side; it remains to be seen whether that will be detrimental.

Note the discolouration of the valve stem near the stem's thread. That's evidence of slight corrosion that may cause stem sealing to be iffy.

The Test

I assembled the cleaned up valve, using silicone grease on the valve's threads, and all its stem-sealing surfaces. I rigged a test fixture that allows me to install the valve onto a faucet that has a 3/4" hose-fitting thread on it. Here's a view of the valve in 'operation'.

The photo shows the valve pressurized and fully opened. The valve's output end is closed, as it would be if it were supplying a closed faucet.

It looks good. There's not a hint of weeping at the valve stem.

So, that turned out well. It would be safe to put that valve in operation in an actual faucet installation.

# # #

FEEDBACK

# # #

Lexicon -- Rule/Ruler

In my junior high school years (grades seven and eight), we had excellent metalworking and woodworking shops. I can't recall the man's name, but one of the woodworking teacher's pet peeves was the use of the word 'ruler' for 'rule'. Whenever a student would call a 'rule' a 'ruler', the teacher would point out to him that, "The Queen of England is a ruler; the measuring tool is a rule."

LittleMachineShop.com has a good article on steel rules and their use. Note that they consistently abstain from use of the word 'ruler' -- the tool is called a 'rule'.

# # #

FEEDBACK

# # #

Miele S2 Momentum Vacuum Cleaner Service Note

The Miele S2 Momentum is a fine piece of high-tech machinery; that is to say that it's largely unrepairable by conventional means in a home workshop. If the machine's electronics or motor develop a problem, you'll be out of luck -- you'll have to take it to a shop that's equipped to deal with the machine's architecture. However, it's still worthwhile to check out a dead machine's fundamentals -- even sophisticated machines are prone to simple failures.

Our unit died on us recently, and the trouble turned out to be an open circuit condition due to a line cord plug defect. Here's a view of what I discovered within the line cord plug.

The plug's neutral tine had fractured within the plug's encapsulation. When I cut and filed away the plug's encapsulation, the neutral tine came away with just a nudge. A conventional, screw-terminal Leviton plug from Canadian Tire made for a neat repair, like so.

The machine is back in business at very little cost. A factory-authorized repair outlet would no doubt have insisted on replacing the entire cord reel assembly to effect a repair -- easily a $100.00 repair job, more than likely.

I had to open up the machine in order to do a continuity test on the line cord. The casing has some concealed claws that make access a bit of a challenge, but once you know about them, it's not too difficult to get the machine opened up. Proceed as follows to open up the machine.

Filter Bag and Filters

Remove the filter bag.

Remove the exhaust filter. (The rectangular filter up on top.)

The remaining rectangular filter in the rear wall of the filter bag compartment can stay in place. (It's the motor pre-filter.)

Lid Removal

Spread the lid at its hinged pivot-points to free the lid from its hinge pins.

Upper Shell Fasteners

There are seven obvious screws to be removed. You'll need a T20 Torx driver. The screws are all the same length.

Foot Switch Cap

This is the tricky part. It's pretty much impossible to show by way of a photograph how this item is fastened. There are four concealed claws at the rear that must be unlatched -- two that keep the foot pedals from flipping up, and two that retain the entire cap.

Start by forcefully raising the front of the foot switch cap with your thumbs. It will snap free upward, getting you to here.

Note that the cap is now tipped up at the front by about one inch from its normal, seated position.

Near the centre-rear of the two 'pedals', there are two claws that keep the pedals down in place. Trip those two claws with a small screwdriver, and you'll get to here.

Now, looking down into the rear of the machine, you'll be able to see the two claws that are holding the rear edge of the cap in place. Trip those claws with a screwdriver, and you'll be able to free the cap completely. Here's what you'll see.

Unlatch the white cover, and you can tip it up to your right, like so.

Free the cable, circuit board and switch from the white cover.

Free the white cover from its hinge pins.

Upper Shell

Down inside a deep well, you'll see one last screw to be removed. With that screw out, pry up the upper shell at the front of the handle to free the front edge of the upper shell. There's also one claw-tower near the rear of the filter bag compartment. Trip that claw, tug the shell forcefully upward and it'll come away. You'll now have full access to the machine's innards, like so.

For the trouble I was having, opening up the machine like this allowed me to do a continuity test on the line cord and its reel. That led me to an unambiguous diagnosis of the problem.

Note the following:

a) The on/off switch is not the power switch for the motor -- it's merely a signalling switch that triggers a solid-state switch.

b) The solid-state motor current switch is embedded in the motor -- it's not a discrete component that's accessible for test or replacement.

c) The circuit board is for motor speed control and, presumably, over-heat detection/shut-off.

Re-assembly Note:

There's a peculiar-looking white flexible shaft associated with the motor speed control knob in the foot switch cap. When reinstalling the foot switch cap, you'll have to take care to guide that shaft so it mates with a potentiometer on the circuit board. Aside from that little detail, re-assembly is reasonably straightforward.

# # #

FEEDBACK

# # #

Ryobi RY09466 Leaf Blower -- Engine Teardown

See this post for the externalities tear down to get the engine out of the machine.

Here's a view of the engine.

I'm only tearing down this engine for amusement. No internal parts are available for it -- an overhaul is not on. I'm just curious about how it looks inside; it has almost no compression, and won't sustain operation at wide open throttle.

So, here goes a step-by-step tear down, for what it's worth.

1) Drain The Oil

2) Air Cleaner Body

- Crankcase ventilation tube off of nipple at top of air cleaner body.

- Primer suction tube off of nipple at right side of carburetor.

- Two M5 prevailing torque hex nuts (8mm A/F).

3) Carburetor & Gasket

They're free to just come off.

4) Breather Check Valves & Tubing

Note the directionality of the two check valves. Each valve's conical end points in the direction of flow.

5) Carburetor Heat Dam, Baffle & Gasket

Two M5x22mm washerhead screws (T25 Torx recess).

The screws were installed with threadlocker, and will take some effort to remove.

The gasket will likely be firmly stuck to the cylinder head.

6) Muffler & Gasket/Heat-Shield

Three M5x38mm truss head screws w/split lockwashers (T25 Torx recess).

7) Spark Plug

It's a Champion RY4C -- 5/8" A/F; 0.025" gap.

8) Ignition Module

I don't have a gap figure for it. It measures about 0.008".

9) Flywheel

A 3", two-jaw puller gets it off nicely.

10) Valve Train Cover & Gasket

One M4x27mm washerhead screw (T20 Torx recess).

11) Crankcase Cover

Nine M4x12mm cap screws (T20 Torx recess).

- - -

And here we have an engine that's well and truly done like dinner.

It's impossible to photograph well, but the cylinder wall scoring is horrific -- you can feel the ridges.

This engine must have been run out of oil. It's a wonder it was still able to run at all.

Conclusion

These little engines demand reasonably conscientious attention. A 65ml sump capacity leaves very little margin for neglect.

This particular engine came to an unfortunate end, but that's no reflection on the engine's quality of manufacture. These machines are jewels of precision engineering and construction, and ought to be treated accordingly.

# # #

FEEDBACK

# # #

Ryobi RY09466 Leaf Blower Tear Down

I have an old Ryobi RY09466 leaf blower with an utterly worn out engine. It was a $2.00 garage sale find that didn't pan out, so it's pretty much landfill. (See this post for the back story, and some basic maintenance information.)

I've got plenty of time, and little else better to do, so I thought I'd tear the machine right down, and at least get a good look at its cylinder wall, to see what the damage looks like. Overhauling the engine is out of the question -- the parts, if I could even get them, would likely cost me at least as much as a new machine. But if I can learn more about small engine architecture, I'll be happy. So, here goes.

Here's a view of the complete machine as obtained.



Its external choke lever is broken off, and the air cleaner cover and filter element are missing. Judging by its very low compression, the machine has seen long service, and heaven only knows how long it was run without an air filter.

1) The Nozzle



Shown above is the nozzle in its latched position. The latching effect is very secure. I needed a big pair of Channellocks to twist the nozzle out of its latched position. Twist CCW (as viewed nozzle-output-end-on) to unlatch it from its studs, then pull it off.



2) The Right Side Engine Cover

Four No. 8 x 11/16" threading screws, and one M4 special shoulder screw (all T20 Torx recess).

3) Right Side Of Handle

Three No. 10 x 3/4" threading screws (T25 Torx recess). Watch out for a little steel rod part (a ground wire) at the top of the handle -- it will be free to fall out once you take away the right side of the handle.

4) Throttle Cable Disconnection

Throttle cable anchor removed from air cleaner body. (One M4x16mm pan head screw -- T20 Torx recess.) Throttle cable disconnected from throttle crank.

5) Kill Switch Disconnection

Two spade terminals.

6) Bottom Right 'Handle'

Two No. 10 x 1/2" truss head screws (T25 Torx recess).

7) Fuel Tank

[The above photo is in error -- the bottom right 'handle' shouldn't be there.]

Two fuel line connections:

- The front-most line connects to the lower carburetor nipple; that's the fuel supply tube.

- The rear-most line connects to the right side primer bulb nipple; that's the fuel return tube.

Three No. 10 x 3/4" pan head screws (T25 Torx recess).

8) Left Side Cover

Seven No. 10 x 3/4" pan head screws (T25 Torx recess); one latch.

9) Impeller

One 3/8" - 24 nylock hex nut (9/16" A/F). The nut is a right hand thread. Use an impact wrench to free it. NOTE the two oversize flat washers.

10) Impeller Housing W/Starter

Four M4x19mm cap screws in deep wells (T20 Torx recess). NOTE the sleeve and flat washer on the output shaft.

- - -

And there we have the engine free of its externalities.



I'll begin a new post for the engine tear down. This post is getting dangerously lengthy.

# # #

FEEDBACK

# # #

Homelite 3514c Chain Saw -- Top Cover Removal

The top cover of the Homelite 3514c chain saw can be a bit obstinate, and the removal procedure given in the operator's manual is hogwash. Here's how to get the top cover off.

First, remove two No. 10 x 5/8" threading screws (T25 Torx recess). They're in deep wells at the rear corners of the cover.

The remaining hindrance to removal is a difficult-to-see hook & stud at the front left of the cover. Here's the best I can do to illustrate how that's dealt with.

You have to get a screwdriver into the sweet spot between the hook, and the left side of the cover. Twist/pry and the little stud on the cover will snap free of the hook, freeing the cover.

Here's a view of the hook & stud that make top cover removal difficult on this machine.

Getting the cover back on is not so easy, either. It tends to fight you at two places.

a) At the left front corner, in the vicinity of the hook & stud, there'll be an overlap that has to be forcefully overcome.

b) At the rear, by the primer bulb, there's a lip that may need to be coaxed into place.

And there we are. Put the two screws back in, and you're away.

# # #

FEEDBACK

# # #