Coping with poor ceramic tile installation and maintenance

Before I get started, let’s make one thing clear: I rent my current home, and hence don’t have an interest in dumping my own money into long-term fixes.

For background… my father was a ceramic tile contractor. An old-school one trained by Italians who knew how to install ceramic tile that would last many generations with no cracks in the tile or the grout. Yes, floating mortar bed on the floors. Mortar on the walls with metal lath. Etc.

My current home wasn’t done that way. In fact, it was done in the worst way, which guarantees problems in a fairly short period of time. All of the main living space was done in quarry tile (which I like; natural color all the way through the tile, inherent non-slip surface, not expensive). However, it was installed using mastic directly over plywood. No real tile man, young or old, would consider this intelligent. Mastic is not waterproof, and tile floors will be mopped or sponged clean. Plywood is flexible, tile and grout are not. The end result is tiles breaking free from the plywood, cracks in the grout, which then permits water to reach the mastic and accelerates the floor’s demise.

If this were my home, the solution would be to tear out the whole floor and replace it correctly. Modern method would be cement board, though I’d prefer a floating mortar bed. But this isn’t my home.

I have identified several loose tiles. A week ago I replaced 4 of them at the entrance to one of the bedrooms. Removed the tiles, removed the mastic, replaced the tiles and re-grouted. This week I replaced 6 in the center of the floor in a heavily trafficked spot. All had broken free of the plywood. Disconcerting to find that someone had attempted to repair this area before by just replacing the cracked grout with caulk. Ugh; doesn’t fix the problem, doesn’t hold up well to traffic, and the caulk on the edges of the tiles would prevent grout from ever sticking to it again. Equally disconcerting was what I found underneath: the trowel used for the mastic clearly was not a thinset trowel, the grooves were too thin. To aggravate things even more, the grooves in the tiles were laid in parallel to the grooves in the mastic. Umm, they’re supposed to be perpendicular.

If I ever meet the hack that installed this floor, I’ll be sure to chastise him. I can’t hold much against the homeowners, I don’t expect them to know the right way to install or repair ceramic tile. If I ever put tile in my own home in the future, I’m going to do it right.

Repairing sprinkler system pressure vacuum breaker

It appears that the main valve and the outdoor cutoff valve to my sprinkler system don’t fully shut off the flow of water. I had noticed this in the winter, when water was dripping out of the PVB test ports. I ignored it at the time because there wasn’t much I could do about it in sub-freezing temperatures. However, I knew the potential consequences… broken PVB innards.

Sure enough, today I opened up the PVB to find the bonnet assembly broken. And water continues to flow into the PVB with the main valve and the outdoor cutoff valve turned off. This mean those valves will need replacing. The main valve is indoors, and I’m not sure why it doesn’t function. Might just be a cheapo, I haven’t looked at it closely since it’s on the ceiling in the basement between joists. What I do know is that it’s not just a slow drip; it’s fast enough to fill the PVB in a couple of hours.

For now I’ve ordered a new Febco 905-212 repair kit for the PVB. It’ll suffice for the summer, but at some point I should replace the main valve in the basement. With water flowing into the PVB all of the time, there’s no way to prevent damage in the winter. I had left the drain spigot open outdoors, but it’s buried in a bucket and apparently it filled and froze which allowed the PVB to fill up with water and freeze too. I don’t understand why the installer decided to bury the bucket in the ground and put the drain valve in it; it’s inconvenient and asking for trouble in bad winters.

Bosch CLPK27-120 (PS21, PS41 and charger)

Today I purchased a Bosch CLPK27-120 from Lowe’s. It’s a bundle consisting of the PS21 12V Pocket Driver, PS41 Impact Driver, two BAT412 batteries, a BC430 charger and a carry bag for all of it.

These are nice tools for my intended purpose. For starters, my old Bosch Ni-Cad drill is getting long in the tooth; it’s seen a lot of use over the many years I’ve owned it, and it’s been dropped many times. The batteries are no longer available, and they don’t hold a charge like they did way back when. Yes, I could have the batteries repacked. However, the reality is that the new lithium-ion tools are much more powerful and I needed a backup anyway, since I don’t know when my old Bosch cordless drill might die completely.

These 2 tools are intended for my automotive tool cart. They’ll be used to run nuts and bolts quickly. They’re small, fairly light, well-balanced and comfortable. For small 12V tools, they’re capable of quite a bit of torque, and the PS21 drill on its lowest clutch setting is unlikely to strip anything, including trim screws that are threaded into thin speed nuts. The batteries charge in about 30 minutes.

The bag is thin and not very protective, but it’s mostly immaterial to me. I will likely buy a Tanos Systainer to hold everything.

Bosch PS41

Bosch PS41

Bosch PS21

Grey Pneumatic Duo-Socket set 81635MRD

This week I received a Grey Pneumatic 81635MRD Duo-Socket set. It’s a 3/8″ drive metric set with shallow and deep sockets from 7mm to 22mm.

Grey Pneumatic 81635MRD Duo-Socket set

Some observations…

The blow-molded case is nicer than I expected. I usually put blow-molded cases in the recycling bin. They’re often very wasteful of space, poorly engineered and poorly built (Wera cases being one of a few exceptions). While the case for the 81635MRD isn’t nearly as nice as a Wera case, it isn’t wasteful of space and I like the fact that there’s a spot for the handle inside the case.

Grey-Pneumatic 81635MRD Duo-Socket set case

The ratchet isn’t terribly well-balanced with a shallow socket, but it’s fine with a deep socket. The handle is comfortable though, and the drive has NO play at all; I’m guessing this ratchet is sealed up better than any other quick-release ratchet I own, and the head is slim with the quick-release button and the direction change lever recessed. I think it’ll work fine in the tight confines of a modern engine bay.

Now to the sockets, which was the whole reason I bought this set. The Duo-Sockets are intended for both manual and impact tools. Just looking at them, I don’t think they’re any thicker than any of my chrome hand sockets, or at least not by much. I’ve no idea how strong they are, and given that I try not to abuse my tools, only time will tell. But I didn’t buy them for use with my impact tools; I bought them because they have large laser etching of the sizes AND a nicely darkened roll-stamp of the size on the base. They’re easier to read than any of my other sockets.

As shipped, all of the parts are coated with rust-prevention goop that’s tacky in feel. I removed it all with Totally Awesome cleaner and water, then coated them with EEZOX. Here’s a picture of two of the sockets.

Grey Pneumatic Duo-Sockets

web site health monitoring: part 2

Last weekend I finished implementing the CPU temperature and filesystem utilization graphs. They work fine, though I may change the filesystem utilization graphs to just be category charts with a single set; filesystem utilization doesn’t change frequently. The latest can be seen here.

I deployed the health monitoring on the new spcarsplus.com web site for Randy. That host doesn’t have CPU temperature reporting, so I made changes to the code to not display that graph if CPU temperatures are not available.

There’s a problem with the BIOS on rfdm.com: the CPU temperatures are incorrect. I have newer BIOS to load, I just haven’t gotten around to it yet.

web site health monitoring: part 1

This past weekend I finished the data collector for web site health. I keep track of CPU temperatures, CPU utilization and filesystem utilization.

The CPU utilization graph is done. The others are in the works. Like my traffic graphs, the user interface is a Wt application.

web site traffic monitoring: part 2

I’m done with the first pass of traffic monitoring. The traffic page can show graps of web site traffic on port 80 for the current day, current week, previous week, current month, previous month, current year and previous year. Good enough for now.

web site traffic monitoring: part 1

Last weekend I wrote a simple program to store traffic statistics (packets and bytes for both input and output) for port 80 of my new web server. Actually, any pcap filter expression can be used, I just happen to only be tracking port 80 at the moment. I save data every 5 minutes.

This weekend I spent a little time writing an application using Wt to graph the traffic data. The graph works, but it needs some cleanup. In the process, I wound up making some changes to the Wt::Chart classes because it didn’t let me use the desired colors for axis labels, titles and legend text. I’ll have to check these changes into my repository so I can diff them and send a patch to the Wt author.

I now just need some utility classes and functions to allow graphing various time periods of interest.

sub-par electronic design in GE appliances

Two days ago my 1994-vintage GE countertop microwave oven started misbehaving. It would not start unless I jiggled the door. I assumed the door switches needed cleaning.

Last night it went further awry. The blower would run when I _opened_ the door and stop when I closed the door. I’m assuming the interlock switches prevented it from running the magnetron, but nonetheless it’s disturbing for the microwave to seem to be running while the door is open.

The root cause: a small, low quality Korean-made microswitch with 120V across the contacts and 10A of current (more during start-up). The switch is rated for 15A and 250V, but… every time the microwave door is opened while the microwave is running, arcing will occur. What happened in my case: the contact that is supposed to be depressed by the plunger when the door is closed had deteriorated to the point where a piece of it fell off. That piece had positioned itself such than when I opened the door, the piece would straddle the remains of the contacts and the microwave would start. Closing the door moved it out of the way, opening the circuit.

I can’t really complain since this was an inexpensive microwave that lasted nearly 17 years. However… it goes to show what can happen when a designer thinks he’s doing the right thing for the target price range but uses a sub-par part. Why a mechanical switch instead of a relay or contactor? Because in theory it tends to have safer modes of failure (high mechanical leverage against the contact spring to prevent contact sticking, etc.). But if you use an el-cheapo part and don’t test it for the many thousands of cycles it’s expected to see over the long haul, you’re gambling.

Arcing wasn’t the only issue. The microswitch housing was deformed from heat. If you ask me, a switch of this size and design shouldn’t be carrying 10A of current on a regular basis. Once the contacts are dirty from arcing, there’s more heat being generated than the housing is designed to handle, which causes the contacts to melt the housing. This accelerates the demise of the switch. When I tried to remove the 2-pole connector from the switch, one of the contacts came right out of the housing instead of the connector coming off of the contact. And it was black from arcing and melted plastic (the switch housing is gray).

Since I’m an electrical engineer by training (but not by profession), I diagnosed the problem and ordered a replacement part. Hopefully I can make it a habit to turn the microwave off from the front panel before opening the door to prevent the switch arcing. There’s nothing I can do about the fact that it carries 10 amps of current when the microwave is on, unless I get motivated to replace it with a normally-open relay and energize the relay coil (low voltage, low current) from the switch instead of letting the switch carry the load current.

I wonder if there are any microwaves with the smarts to open and close the load relay at the zero-crossing of the AC input voltage…

sitemap deployed

I’ve deployed my web site map. This is the result of the work discussed in my post on Using Wt (C++ Web Toolkit) for a web site map. The original application mentioned in that post can now run as a WidgetSet application, and is now embedded in my php page wrappers.

I’m starting to think that it’d be nice to play with replacing my search page with a Wt application. Not because there’s anything wrong with the existing search, but because I’d like to free myself from maintaining the javascript. The javascript for my search page isn’t large nor terrible since I’m using jQuery, but replacing it with Wt would permit graceful degradation. And while javascript is handy, I’m still a non-expert in it.