Sofa repair

As we moved the sofa this morning for the annual cleaning underneath we noticed the right arm seemed loose. We turned this huge, heavy sofa over and observed the arm's wood framing was broken!

Notice the top piece is suppose to be 2 inches to the left with the top piece set into the notch. Staples are all loose.




I was able to fully disconnect this piece except for the fabric, which will allow me to get more glue into the joint. I cut off all the staples.









I found some two and a half inch wood screws and was able to grind off one quarter inch which with the half inch wood spacer made all fit perfectly.












Looks like the repair may work!









Probably stronger than new. (It is a Lane sofa.)

Laptop Computer Repair

I was given a broken laptop computer as there was no video on the screen at all. When power was turned on a couple blue led indicators lit but all else was dead. This is an HP Pavilion tx1000 with Vista installed.



This video chip is know to get too hot on this and similar computers. As it gets hot apparently the solder melts and the chip separates from the mother board causing the failure.

Twice, using a hair dryer, I tried to heat up the video chip on the motherboard enough to reflow the solder without help. Apparently the hair dryer was not getting the solder hot enough. Then once I tried using a heat lamp 2 inches from the board but ended up blowing up the bulb, literally. Then I purchased a better tool which is sort of a heat gun with higher temperature output like 400 degrees Fahrenheit on the low setting and 800 degrees on the high setting. Using the new tool I fried that chip until the little chips board was getting heat blisters. Then assembled the little computer leaving out 5 screws as they are not fitting or no place observable to insert them. And by now I doubted the computer would ever function again.

I powered it up and “Walla“, video on the screen! Windows Vista kept wanting to upgrade which I did several times. I connected the computer up to the internet using an Ethernet cable and it worked fine. The antenna to the Wifi was and still is broken so that is not working.



It is hard to determine how long the computer will continue to run. Possibly it is fixed for the long haul. Who knows? I would keep the computer off laps and such to ensure it can get enough cooling air.

The original owners are welcome to have this computer back as it probably has some personnel files on it. One owners files are password protected. If they don’t want it back I will need to delete all the personnel stuff and go from there.

The video chip is cooled with the same fan and duct work as the main processor. There was a little dust in the duct blocking maybe 10% of the air flow. The dust was easily removed when I had everything apart. Kind of interesting to work on a little unit like this. It is amazing how easy the hard drive comes out. Not so amazing how the DVD unit comes out. The keyboard and motherboard came out rather slowly. Of course I have not disassembled one before this so maybe next time will be faster.

DSL Century Link

Good old Century Link. On the Seahawks game they advertised high speed DSL for $19.95/mo for a 5 year commitment. When I called the following Monday they didn’t seem to recognize that deal but offered to cut my bill by $10/mo to $46 for year then $56.45/mo for both phone and DSL. And DSL would increase from 526 kb/s to 768 kb/s. They would also throw in call waiting and caller ID. Still not fast enough for good quality netflix which needs 3 mb/s. I checked my download speed and am getting right at 700 kb/s with the upgrade. Seems a lot faster than before. Youtube items don’t have to buffer anymore.

Tektonix Oscilloscope Repair

Alain found a couple oscilloscopes at a yard sale and called to see if I was interested. The Tektronix Digital Storage 100 Mhz scope sounded real interesting. (Model 2232 produced about 1990.) He bought the scope for $40. At home the trace triggered and displayed but all was out of focus and the focus knob did not go far enough in the improving direction.



I was able to download the 366 page PDF Service Manual off the internet. This manual has the description of operation and also the schematics! What a pleasant find!

On page 285 I found the focus circuit schematic.


I then took the cover off the scope and eventually found the series resistors chain on the bottom board and they were well marked. Using an ohm meter I found R890 open instead of reading 510 k ohms. Since the failure was so clear I did not even remove the circuit board to observe the failed resistor. I simply scabbed a new resistor on the bottom of the board. Remember the training (KISS = Keep It Simple Sam)?



I cut an opening in a plastic high voltage protection plate to make room for the new resistor. Now all works as designed. At least the focus is good, the traces display and the triggering works. Now to read the manual to figure out the many other features of this rather powerful scope.



Also I should replace a missing screw that holds the back cover on.

Viking Husqvarna Model 6440 Sewing Machine

Failure and Repair.

Linda’s 33 year old, ‘vintage’ sewing machine started smoking the other night. The machine was just sitting there when the motor started by itself and smoke emerged from the machine! They unplugged the machine but there remained a ‘nice’ odor in the room. This has been an excellent sewing machine over the years.

We plugged it in the next day and the motor started at a slow speed without depressing the foot pedal. After concluding the machine is not worth much anymore I started the disassembly. I was able to eventually get to the motor and the little terminal box that held some electronics. There was capacitor that had blown up leaving a moist oil like substance on the terminal board. The cap had a label indicating it was 0.1 uf, 250V ~ MP, fo = 3.6 Mhz, PME 271M. This turned out to be a interference suppressor used, I think, to reduce electrical noise caused by the motor.. I looked for a replacement capacitor but found only one half the size that sold in lots of 200 for about $2 each. ($400).

The motor and terminal board assembly.

The blown capacitor. Its belly is missing.

I didn’t want to leave the machine disassembled too long for fear I may not get it back together correctly so I completely removed the capacitor. Now the sewing machine works just fine. Maybe when the motor is running we will hear interference on our radio or tv. I may look further for a replacement part as time permits?

Here the beauty is.

I wonder how many more years of service this machine will provide? There are some new machines out there even in the $150 neighborhood that may outperform this vintage sewing machine. Who knows?

The well water

We started thinking our well water was tasting poorly a month or so ago. I inspected our 30 inch round shallow well and all seemed ok. I cleaned the well using bleach. The water never did taste of bleach as it must have all dissipated or been diluted too much by our reservoir. The taste improved but was not as it should be.

So this time, two weeks later, I dug down a foot to the 1000 gallon reservoir lid and inspected the reservoir. All seemed clean and the water was nice and clear. It has been 11 years since I have looked inside the reservoir.

I dumped 4 cups of bleach in the full reservoir and 2 cups of bleach in the full well. Then I closed the valve between the well and reservoir and started draining both using both pumps dumping the water through 5/8 hoses without any nozzle. The well was drained to the upper shutoff float after 20 minutes. I added another 1.5 cups of bleach and hosed down the walls of the well real good with the bleached well water.

The well is quite slow in recovery but always has water. At one time it had a recovery of 1.3 gallons a minute. This equals more than 60 gallons an hour and with the reservoir the well provides plenty of water for our home.

After 2 hours and 20 minutes the reservoir was down to maybe a foot of water remaining. I don’t want to drain it below the water pickup pipe or the system would loose the pump prime. The way the plumbing is configured if it looses a prime you almost need to wait until the reservoir is half full before you can start the priming process. In the last 20 years I don’t think we have ever lost a prime. We did loose it a couple times early on when the float switches were being adjusted.

I added two cups of bleach to both the well and reservoir and washed down the reservoir with the hose using the bleached reservoir water. This water turned almost muddy brown much to my surprise!

I opened the valve between the well and reservoir and now am just waiting for the particulates to settle out. I could have emptied the reservoir one more time but we have been gone some. If I would have emptied the well it would have cleaned the particulates out earlier.

Now 3 days later barely can smell the bleach in the house water and there is a slight turbidity in the water. Hopefully the taste will be back to its usual quality which I believe to be superior to the bottled water that is purchased at the store.

The water is purified by an Ultra Violet lamp so as long as the turbidity is gone the water is good as far as bacteria is concerned.

1975 Dryer repair

Looks like our 1975 dryer is working as designed (almost). It took 15 minutes to get to the problem which was a bad control switch (timer). I priced new switches and the price ranged from $208 to $150. If I sent our switch in and they could rebuild they would likely charge $74 or for $20 more I could get an immediate rebuild but would still need to send mine in. (The original part is no longer made so they have substitutes that fit, they say.

The dryer has been an excellent machine. It is a Maytag model kde407 series 01. As I understand it moves a lot of air and does not get the clothes too warm while drying which makes it good on the clothes and efficient also, as moving air is cheap compared to heating air. The unit is rated at 4800 watts which means it could draws 20 amps at 240 volts. The spinning motor runs on just 120 volts. There is a heat temperature switch which I suspect cycles the heating element on and off keeping the air at a controlled temperature. Then there is another overheat switch in case of a malfunction. I am pessimistic a new machine would be more efficient.

After taking the control switch apart I found that the two inch plastic disc had separated from the splinned metal shaft causing the failure. The disc controls all the length of times for the different drying cycles and also turns on the heat if needed for any cycle.





After a little research I decided to glue the plastic disc to the metal shaft using JB Weld. I let cure overnight. I was aware before gluing that I had no idea how to align the plastic disc to the shaft and if out of aligned it would skew all the settings shown on the control panel. Oh well it would have taken too long to research that out.

While putting switch back together I noticed the spring had sprung off somewhere! (Kids - oh phooey - probably can’t blame it on kids or grand kids.) I remember just where I had left that spring but likely when I vacuumed everything I must have tipped the spring out of place. So then comes out the 2 million candlepower flashlight to search the floor and shine in the small opening to see inside the dryer. No luck. So now another 10 minutes to get the back off. I found the spring easily and went ahead and vacuumed all out which included 39 cents, 3 allen wrenches and two buttons.

So, now all is back together and the dial is 10 degrees off and after testing I suspect everything is working. I did place a new mark on the base of the control dial indicating the setting point of the switch. A good thing is the little black mark I added does not seem to clash with the avocado green dryer.