A Beautiful Old Chair

During the pandemic, I fixed a chair! Well, part of a chair. 

The problem: 

It was broken. (All good repair stories start here...) The wooden legs dovetail into a cast iron center piece. The corners of the wooden dovetails had split along the grain, causing the legs to fall out, and the area where the casters attach to the wooden legs was worn badly. 

I didn't take a good picture before I started, because I wasn't planning to write this. But, by popular demand, I'm blogging again. You will just have to pay attention to the in-progress pictures to see what is being fixed and why. (Or, skip to the end and take a peek if you are OK with spoilers.)

The solution: 

Steel. I like steel (and metalworking/machining in general.) It seems like the right amount of overkill for this. 

First, some context. Then we will go back to the beginning. Here you can see the four wooden legs, and the center piece that they dovetail into. My repair was making the metal banding that follows the curves of the legs and dovetails into the center piece. 

Step one. Buy materials. In this case, my local hardware store had 3/16" thick steel flat bar in exactly the width I needed to match the wooden legs. Two 3 ft. pieces set me back $13. 

Step two. Play with fire. I'd recently gotten an oxy-propane torch to play with brazing. Turns out it can also be used for bending. I heated the end and used my bench vise and a hammer to create a decent 90 degree bend. The short portion at the end will lock into the widest part of the metal dovetail socket. The long end will be bent to match the curve of the chair legs. 

Step three. Bend the steel. It took a while fiddling with things to match the curves closely enough to make me happy. All bending was done by hand, with the help of some parallel-jaw pliers and a sturdy bench vise. 

Step four. File to fit the dovetail socket. I found a place to buy a decent large file for a reasonable price. The downside is that they are sold in a package of six. That's not all bad news, in that the extras will be given to friends. I could have used an angle grinder, but that is noisy, and it is way too easy to take off too much material. Using a good file, this went surprisingly quickly, was rather cathartic, and I got a very good fit. 

Step five. Drill and countersink holes. My plan is for these to be screwed to the bottom of the legs. For that to happen, they need screw holes. This would have been easier to do before bending. Thinking ahead is not one of my strongest skills. And, I only screwed up the alternating pattern on one of the legs. Oops. I couldn't have done this without a drill press and a decent vice. 

Step six. Weld the caster posts in place. The posts for the casters were mounted on plates that were a bit too wide for the legs. My answer was remove the posts and weld them to the steel. I was really happy with how this turned out. Well, at least until I turned it over. I wasn't thrilled with the tiny gap between the wide part of the post and the steel. 

Step seven. Silver brazing to the rescue! Fill the insignificant gap by brazing. (I mean, I have the torch. I'd be a crime not to use it... This step was totally necessary. I don't know what you are talking about.)

Bonus:  these pictures of the brazing process are beautiful! 

Step eight. Prime and paint. The color is Rust-oleum Universal Oil Rubbed Bronze. It's a good color. Goes with everything, or so I've heard. This used up the last dregs of a can I had sitting around.

Step nine. Fill in the worn hole left by the old-style casters. The wood was cracking here on all the legs, so I figured it could do with some reinforcement. I drilled it to fit a standard sized wooden dowel and glued in pieces. Cost of dowel was about $3.

Step ten. Drive some long screws into the end of the dovetail on the legs. The heads of these fit into the gap between the wood and metal pieces at the dovetail. Later pictures will make this clearer. This gap will be filled with epoxy, and the screw heads will anchor it into the epoxy.

Step eleven. Seal the perimeter of the dovetail connection between the wood and metal. This will prevent the epoxy from leaking out wherever there is a gap. I had this old sealant sitting around. It still worked, and the dark gray matched the color scheme. 

Step twelve. With the sealant cured, fill the gap with epoxy. The top view here shows the gap I'm referring to. I used some steel BBs as filler to make the epoxy last longer. I had these left over from when Dad and I replaced a handle on a sledgehammer in high school. I also got to use up all the leftover epoxies I had sitting around getting old. You will notice that I didn't fill it all the way to the top. I had to leave room for the end of the metal pieces to fit down in there. 

Steps thirteen (epoxy) and fourteen (screws). (I clearly didn't take enough pictures.) Fill the remainder of the gap with just epoxy and push the metal pieces down into it. I also coated the entire area between the wood and metal with epoxy, for it to bed into and fill any small gaps. Next screw the metal pieces into the wood. I spent about $10 on different length wood screws to account for the tapering thickness of the legs. You can also see in this picture that I had to shim the space between the center support and the legs since there were some gaps. 

Step fifteen. Install the center support piece. Use the threaded holes I forgot to mention making back in step five. Curse when two of the holes don't quite line up. Modify the center piece to make it work. No one will ever know. 

Step sixteen. (Not pictured.) Reinstall and shim the casters to sit flat. Did I mention that I didn't take enough pictures? 

Complete! And, beautiful. Hopefully it is strong enough. Now it goes back to my friend to be reunited with the rest of the chair. This was a joy to work on. 

Total cost: about $26. Not bad. 

Line Cutter Blade

When scuba diving, it is important to be able to cut your way out of tangles. This is especially true if you are diving in places where people go fishing. It is difficult to see monofilament fishing line underwater. Entanglement is a real hazard.

For this reason, most scuba divers carry a dive knife with them. It is also a good idea to have an easily accessible backup, just in case your normal knife is lost or cannot be reached.

I own a Dive Rite Z-Knife line cutter as a backup.

It is based on the design of a parachute line cutter for cutting away a tangled chute before opening the spare. It has a razor sharp blade, and its shape minimizes the risk of accidentally cutting yourself when using it.

I like it, but there is one disappointing drawback. If you happen to try to cut steel fishing cable, you will only succeed in destroying that sharp little blade. It also has the tendency to rust over time. (Mine lasted a few months before rusting, but only one trip before I tried cutting something it couldn't.)

They don't sell replacement blades.

Or at least not ones that I could find.
These people couldn't find them either.
These people had some ideas, but nothing readily available.

So. Since it appeared that the only option was replacing the whole thing, I had nothing to lose by trying to modify mine.

First, I removed the old blade. It measured 26 mm by 8 mm.

Next, I scoured the internet trying to find an identical replacement. No luck.

Finally I went to the local hardware store and found this. It has a stainless blade (not sure what grade, but we'll see how it lasts), and the blade width of 9 mm is very close to the 8 mm blade I removed.

I broke off a section that consisted of four segments of the blade, and ended up with this piece. It is remarkably close in size to the blade I removed.

Next, I partially pushed in the new blade. It was a little difficult. I could tell that the blade was larger. To fix this, I used the pencil torch from my arsenal. I heated the point of the blade for a few seconds and then used needle-nosed pliers to pull the hot blade into place. This melted away some of the plastic, making room for the different-shaped blade end. It still interfered with the screw hole after the first time, so I pulled it back, reheated, and pushed it a little further. Below you can see the before and after.

Using the needle-nose pliers, it was pretty easy to remove and install the blade at this point. (I took the comparison pictures of the two blades after doing this. That's why the tip of the new blade is discolored in the pictures at the beginning.)

Here you can see the final result. The blade is firmly held in place by the screw.

There was enough left of the box cutter blade to make 3 more of these replacements. We'll see how long they last, but this appears to be much more economical than replacing it each time the blade is damaged or rusts.

Adventures in Plumbing

My parents' house has a well that supplies their water. About a year ago, they had a less-than-competent contractor install a storage cistern and a booster pump. 

The contractor didn't anchor down the pump base, depending entirely on the weak PVC pipe and gravity to hold it in place against constant vibration. The electrical work he did had to be completely redone by someone else. The concrete cistern has leaked since day one, even after several repair attempts by the original contractor 

The pump started leaking much more recently, and much worse. What looks like a blurry water drop at the rightmost corner is a constant stream. This is what the leak looked like with the booster pump turned off and the piping downstream depressured. 

The first step I took was to disconnect the piping from the downstream union and I began to unscrew it from the pump. The pipe was loose! It wasn't even screwed in tightly. The piping configuration makes it impossible for the pipe to unscrew itself from the pump without disconnecting it downstream. Here is an overview of the pump and piping configuration. The piece that I removed comes out of the top of the pump and connects to the half of the union seen above and to the right of the opening.

Once I had the piping removed, I took a closer look at the opening on the pump. This is what I saw. 

There was metal sticking out into the bottom portion of the threaded opening. It looked like it might be flash left over from when the pump housing was cast. It deserved a closer look. 

That's strange... It looks like the threads abruptly stop.

Yup. The threads definitely stop. My only thought is that this might have been done to prevent threading the pipe in too far. If the pipe went past the inside surface of the pump case, it could hit the impeller (the part that spins.) 

Let's take a close look at the pipe I removed. 

The first thread at the end of the pipe is rather screwed up. It's as if it were tightened past that point where the threads in the pump stopped. It's almost exactly like that. 

At this point it is important to understand how tapered pipe threads are supposed to seal. The seal occurs at the threads as they fit tightly together. This site provides excellent diagrams of what should be happening. I have modified them below to illustrate what was happening in this specific case. When the pipe bottomed out, the threads were still loosely engaged. This allowed the water to leak out past the threads. I used a saw to shorten the pipe, removing the two smallest threads at the end. It was then able to seal tightly. A small amount of Teflon tape or joint compound seals any small gaps left in the imperfect threads. 

Below you can see the before and after pictures of the pipe. 

Based on what I showed above, this is what I think happened. The contractor screwed the pipe in place, tightened it to the point it became difficult, and then discovered that it leaked. When it leaked, he tightened the crap out of it until it stopped leaking, damaging the plastic pipe thread as it bottomed out in the hole. However, the threads were still not properly tight. The only reason it stopped leaking was due to the rather excessive amount of joint compound that was used. 

This is pipe joint compound. More is not better... 

The contractor saw the opening of the pump when he assembled the system. He failed to notice the rather obvious metal bits extending into where the pipe should be threaded. This is one more example of the shoddy job that was done all-around. 

Here is the final result after my repairs. If you compare this to the original picture of the leak, you can see that the pipe threaded in further. This created a good tight seal that should last. 

The leak started shortly after we had replaced the filter downstream of the pump. What we did must have been just enough to disturb the loose joint and start the leak. Both the inlet and outlet connections on the pump had the same problem, and were fixed the same way.

I dislike incompetence. Consistency doesn't make it better.

Tool Box Repair

This is a tale of overcoming poor customer service.

I have to be fair. It was not terrible customer service. I don't even think I would call it bad customer service. It just wasn't good customer service.

Let's start at the beginning.

For the past couple years, I have been making do with my tools stored in various cardboard boxes and tool bags. This is less than optimal, especially when I am digging through a box unable to find what I was looking for.

On Black Friday, with the encouragement and support of my girlfriend, I purchased a tool box.

A large tool box.

A beautiful tool box with shallow drawers that can hold a single layer of well-organized tools.


I purchased it at a Lowes that was three hours away from where I live. I was spending Thanksgiving with family in the area.

Once I got it home, I unpacked it, and discovered a sad surprise. The front of one of the drawers was damaged.




It looks like it was hit with something. The aluminum handle was scraped and bent. The stainless drawer front was also bent. It was bad enough to have broken the rivet that attached that end of the handle to the drawer.

This made me sad.

I had noticed a hole in the cardboard box when we were loading it into my car, but I hadn't thought anything of it at the time. If I had caught it then, I could have exchanged it on the spot. That would have been much easier. I think the lesson to be learned is to unpack things before leaving the parking lot. Especially if there is any damage to the packaging. Oh well.

Luckily, there was a customer service number printed on the front cover of the instruction manual. It said to call them before returning it to the store. It stated their hours to be 8 a.m. to 8 p.m. Monday through Friday.

It was early in the evening, so I gave them a call. I was quickly informed that the department I needed for my product closed at 5:00 or 6:00 p.m. and was given a different number to try the next business day. It annoyed me that both the number and hours printed on the manual for my product were wrong.


When I got ahold of them, I was given an email address and told to send them my information, a copy of the receipt, and a clear description of the problem.

I couldn't find my receipt, which made me annoyed with myself. Luckily Lowes has an easy way to request a duplicate receipt. It took 10 business days, which I was perfectly fine with. I was the one that had lost the receipt, after all. Once I had a copy of the receipt, I sent the email. The email included the sentence:

The face of the drawer measures approximately 23" wide by 2" tall.

I got a response the same day. They did not have the drawer front available, but they did have the handle. I was disappointed, and I considered taking it back. But, it is rather heavy and difficult to move. I asked them to send me the handle since that is what had the worst damage. I was pretty sure I could straighten the drawer front.

I had access to a 20 ton shop press. I used it and some gentle guidance with a rubber mallet to flatten out the bent drawer front.

Here is the before picture:

 And this is what it looked like after.

It is not perfect, but few things are. 

Six days later, I had a package waiting for me. It was a drawer handle. It even included replacement rivets.

The only problem with it was that it was the wrong handle. The one they sent me was 36.5" long. I considered cutting it to size, but none of the rivet holes lined up. I was hesitant to drill the holes since they had to line up perfectly with the ones on the drawer for the rivets to hold, and it was an awkward angle to drill in place.

I emailed back and explained the misunderstanding. They respond the next day that they will gladly supply the correct one after I ship back the one they sent.

I asked how they would like to arrange to pay for return shipping, and I didn't hear from them for eight days. They finally emailed me a shipping label.

The replacement replacement part was mailed after they received the one I sent back, and this is what arrived:








The top handle is the damaged one. The bottom is the replacement. This time it was the correct length, but the rivet holes still did not match.

I decided that this was probably the best I was going to get from them. They had the model number and exact location and size of the drawer from the very beginning. They couldn't supply the correct part after two tries.

I carefully drilled holes in the correct locations:








I then pop-riveted the handle back in place. The rivets that they had supplied were just a bit too long to hold it tightly. Another minor incompetence.

With some shorter rivets, this was the final result:

This is more than good enough to make me happy. In the end, it was easier than lugging the thing back to the store, but not nearly as easy as it should have been. If they had supplied the complete drawer, replacements for both damaged parts, or even the correct drawer handle, it would have been a much quicker repair.

I am very happy with my repaired tool box. It seems well-made and has been a joy to use. I would recommend it, so long as you never need to depend on their customer service.

EVO 3D Digitizer Install

Sorry for the long delay between this post and Part 1 / Part 2 of the broken EVO 3D digitizer saga. I was tempted to leave the story unfinished forever because of the comic below entitled "Wisdom of the Ancients:"

But I wouldn't do that to you.

A quick side note. If you don't read XKCD, you really should. It is one of the most consistently brilliant webcomics I have ever had the pleasure of reading. So when you are done here, go read and subscribe to the RSS. And be sure to read the mouseover text for each comic. You will not regret it.

Back to the phone. From this point forward, I have decided to be consistent on how I refer to the part I am replacing. The phrase "touch screen" is too ambiguous for my taste. There are two parts that make up the touch screen. The touch part is built onto the back of the glass face of the phone. This is the digitizer. The screen part is behind the digitizer and is just a normal LCD screen. If you crack the glass on your phone, but the picture still shows up ok, you broke the digitizer. If the picture is messed up, you broke the screen. I'm glad we had this little talk. I feel better now.

The digitizer I ordered arrived from Amazon. It has a plastic film on the face of the glass to protect it. However, the back side of the digitizer is not glass. It is plastic. Easily scratched plastic. This digitizer arrived with several scratches on the non-glass side. Not cool. It also does not come with replacement adhesive for holding it in place. The description says, "Adhesive is on the back of flex, just peel off and apply," but apparently this only refers to a small rectangle of adhesive on the cable, not the adhesive that holds the digitizer in place. 


I will continue with the replacement anyway for a couple reasons. First, it will prove whether this part is causing my problem or not. Second, even if there are some scratches, if it fixes the problem my phone will be usable again. Since I am suffering from a severe case of smartphone withdrawal, I will install this semi-defective part and leave an unflatteringly truthful review on Amazon.

I now have a replacement digitizer and a video on how to take apart most of the phone. I follow the video and begin the disassembly. It goes well. Soon I have a pile of tiny parts where there was once a phone. I reach the end of the video, but it leaves me with the digitizer and screen still firmly entrenched in the front part of the case. It gives some vague advice about using heat and prying everything apart like on other HTC phones, but that is not so helpful to someone who hasn't done this to other phones.

It does point me in the right direction though. Armed with their somewhat nebulous comment, I go back into research mode. The HTC EVO 4G looks similar to the 3D, and it has been on the market much longer. Maybe there is a better guide for removing the digitizer on that phone. It turns out that there is.

So. I now have a very good photo tutorial on how to remove a similar digitizer. The following photos are blatantly stolen from ifixit.com in case they decide to take down the tutorial. Links are provided giving them full credit, so hopefully they will not be too upset.

The video leaves off at the point that corresponds to Step 20 on the EVO 4G teardown guide. This step has you start applying heat (but not too much heat) to the outside edge of the digitizer. The digitizer is held in place by adhesive. It is some form of very thin double-sided tape. Once you heat up an edge, you can start prying the digitizer from the front part of the case. The following few steps go through heating and prying each edge of the digitizer. At this point on the EVO 4G, you would be done. Remove the digitizer and stick the new one in place.

The EVO 3D is slightly different. Once you have battled the adhesive and removed your old digitizer, you will discover that the cable runs between the screen and the case. To get the cable out (and insert the new one) you have to remove the screen as well. This is not good news. In removing the digitizer on my phone, I destroyed it. The plastic film on the back side of the glass that does the actual sensing work was damaged along the top edge. This is no big deal, since I am replacing this part. However, now I have to remove the screen. My screen works fine. I have no replacement for it. I do not want to hurt it by removing it roughly.

Having no other choice, I continue with Step 33 on removing the screen. The screen is held on by two strips of adhesive, one on each of the long sides of the screen. (Left and Right when holding the phone normally - i.e. portrait, not landscape.) At this point, I get to apply heat directly to the LCD. This makes me a bit nervous, but I have come this far already. Going slowly, I apply heat and pry.. heat more and pry... and continue until it comes loose. Then I repeat for the other side. The only mistake I made was probably using too little heat to start with. Things went better with a little more heat.

I must note at this point that I am using a heat gun with pretty good temperature control. The lowest setting is 200F and that is what I used throughout. If you are using a heat gun without temperature control, I would worry more about damaging something. Just saying.

At this point, the screen is removed. It even looks to be undamaged. Now I get to re-assemble. Having no other option, I reused the old adhesive to hold both the screen and the new digitizer in place. I would not recommend reusing the adhesive for the digitizer. It attracts dust and lint like a magnet. Especially if you try to clean your fingerprints off of the screen. The fingerprints which you will inevitably get over everything as you try to pry things apart. Anything caught on the inner edge of the adhesive will show up around the outer edge of the display once it is all back together. You are much better off removing the old adhesive, cleaning everything up, and then applying new adhesive. Assembly is reverse of removal, but much easier. When putting it back together, there is no prying or heating.

Everything is back together. Now comes the moment of truth. Is it better? Is the problem solved, or did you break something going through this process?

...

Success! The screen is unharmed. Yay! The digitizer is responsive again. My phone works! Now to deal with the scratches... Which means getting another digitizer and repeating the entire process. At least this time I will have a better idea of what I am doing. Yay...  :-/


I feel that I must apologize for the lack of pictures in this post. My phone serves as my digital camera. I couldn't figure out a way to use it to take a picture of itself disassembled. I tried to describe what I encountered using words alone, but if it is terribly unclear, I refer you to the XKCD comic linked at the beginning of this post.