Archive for August, 2010

A 15 Year Old Car is like a Woman

Posted in Auto Maintenance, Troubleshooting on August 30, 2010 by themidnightengineer

Two words: high maintenance.

There’s been a vexing problem with my 95 Lexus ES300 ever since I purchased it for $700 in cold hard cash from my friend Taek back in February. The car constantly needed a jump-start. Taek had the battery and alternator replaced but the issue didn’t go away. When the most obvious solution fails, the problem becomes bigger and more mystifying. The battery was replaced two more times, poor quality being the suspect. No dice. The rear trunk latch was faulty and so I fixed that. I also unplugged the lights for the glove compartment and trunk for good measure. I also discovered and repaired a damaged electrical cable harness under the hood. Each of these issues could have had a bearing on the starting problem and each time I thought I had hit upon the root cause. Yet the problem stubbornly remained. Something was draining the charge on the battery. Leaving the car parked for more than 24 hours resulted in a dead battery and ignition failure, requiring a call to AAA to request a jump-start. However, disconnecting the cable from the positive terminal on the battery prevented the drain and served as a temporary fix.

I took the car to the Lexus dealer and explained the situation. They did some tests and told me that I needed to replace the battery. That was singularly unhelpful since I had gone down this route already. I suppose it is possible that three different batteries in a row could all be bad but its highly doubtful.

This weekend I measured the current drain on the battery using my multimeter.

This current draw is equivalent to leaving the car door open (which results in several lights being turned on).

My car has three fuse boxes (two under the hood and one below the steering wheel). To pinpoint which electrical sub-system was causing the drain, I pulled each fuse one by one until I saw the current draw drop to a nominal level.

This is one of the fuse boxes located under the hood. I pulled out the RADIO fuse.

The reading on the multimeter dropped from ~ 0.59 A to ~0.03 A.

So now I know exactly what’s been causing the drain. For now, I will leave that fuse unconnected.

Troubleshooting this car is like playing Whack-A-Mole. You take care of one problem and two or three other problems emerge. Next, I need to figure out why the windshield wiper fluid refuses to spray.

New Candle Supply Order

Posted in Candle Making on August 25, 2010 by themidnightengineer

Decided to try out Ecosoya CB Advanced Soy Wax. Golden Brands 464 melts too easily in the summer heat.

Max Fragrance: 1.5 oz per lb

Melt Point: 111°F     Pour Temp: 124°F (+/- 5°)     Heat to 185°F

New fragrances:

Chardonnay, Love Spell, Dragon’s Blood

Needed: A Workbench

Posted in Miscellaneous, Other People's Work on August 25, 2010 by themidnightengineer

A couple of photos I found online for ideas on how to build a workbench.

New Toner Transfer Mask: Hello Kitty

Posted in Artwork on August 12, 2010 by themidnightengineer

By special request, I’ve been asked to make tins with Hello Kitty etched on it.

The following are the masks.  I like it because, unlike the previous Rhinoceros, there is minimal fine detail.

Saltwater Electrolysis Etching of Stainless Steel Tins

Posted in Saltwater Etching on August 8, 2010 by themidnightengineer

Using Scotchbrite abrasive pads, I sanded the surface of the tin where the image would be etched. The tins have a thin, plastic coating which must be removed.

The image I wanted to etch is a woodcut print by Albrecht Dürer, Rhinoceros. Using GIMP, I scaled the image to fit on the tin cover, did a inverse transform, and saved the final image as a negative.

I printed the negative onto a sheet of Press & Peel Blue film using a laser printer. Press & Peel Blue is also used to transfer pre-etch trace outlines onto printed circuit boards. After cutting out the printed image from the sheet, I then ironed it on to the tin cover for at least  10 minutes.

After the ironing, I quenched it under cold running water and peeled off the Press & Peel Blue from the tin.

I have an electrolysis setup which includes a plastic Brita water filter tank that I found discarded in the sidewalk one day and a modified DC power supply that I salvaged from an old Cisco router. I filled the tank with a gallon of lukewarm water and dissolved about a cup of salt in it.

I used the +12V terminal on my power supply which is rated at a max current of 5A. I hooked up my multimeter to measure the current and it read OL. The multimeter is rated to measure up to 2A, the OL indicated that I was pushing more than 2A through the solution. BTW, anything over 100mA is sufficient to cause death by electrocution. The specimen was connected to the positive lead cable (red) while a dummy tin was connected to ground (black).

After the electrolysis, I cleaned off the toner mask using a cloth and “Goof Off” spray.

The result:

I’m still in trial and error phase.

Notes:

1. I need to get a decent Fluke multimeter so that I can measure both the current and resistance of my setup.

2. The toner mask transfer is still a work in progress. The Press & Peel Blue film has a tendency to leave spots and there are places where the image didn’t stick as well as I would have like. I will try using glossy magazine paper.