Makita Battery Pack Repair

January 12, 2010 by Mike Szczys 69 Comments

[Rob] grew tired of his Makita power tool battery packs dying so he figured out how to repair them himself. The video after the break walks us through the process which starts by cracking open the case. Inside there is a controller board and a battery of ten cells. [Rob] has pinpointed these battery failures to just the first cell, which is confirmed by measuring the cell voltages with a multimeter. The first cell in the demonstration battery reads zero volts and needs to be replaced. For some reason he’s got heck of a lot of these cells on hand, at the end of the video he shows off a massive block of them that provides one half of a kilowatt-hour of power.

To complete the resurrection he removed the control circuitry from the integrated PCB. It seems that the microcontroller on the battery’s PCB monitors it and bricks them when it thinks the life of the unit has ended. By hacking a charger he can now balance-charge the altered battery packs and get more use out of them before they hit the landfill.

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Don’t Put That EPROM In Your Mouth!

January 12, 2010 by Mike Szczys 60 Comments

[Jeremy] had some chips on hand that included EPROM. We’re not talking about EEPROM, we mean EPROM that need a UV light source to erase. Most people don’t want to drop a few hundred dollars on a dedicated EPROM eraser, there must be another way.

Boy, EPROM really suck. But so do pacifiers and he already had a solution for exposing those to UV. He pulled out his $30 UV pacifier cleaner and tossed the chip inside. Two times through the cleaning cycle and the data was gone. We’ve looked into using UV LEDs to do the job but some experimentation shows that it doesn’t work. These pacifier cleaners are cheap and easy to get a hold of. The real question is are you still using chips that require UV for erasing?

Version Control For Eagle

January 7, 2010 by Mike Szczys 29 Comments

[Jeff] set up version control for Eagle libraries and projects. He mentions that Eagle has become the standard for open source hardware projects and he’s absolutely right. We use it for our projects, and we’ve grown to expect that the posts we feature have Eagle files available in most cases.

But Eagle falls short in its library management. There is some amazing work from SparkFun to support a usable parts library, but who hasn’t added parts themselves? [Jeff] setup libraries using github so that changes and additions to the libraries can benefit all and cut the amount of time spent making custom footprints for new components and packages.

RepRap Acrylic Extrusion Using Hotbed

January 5, 2010 by Mike Szczys 16 Comments

[Nophead] started the year off by successfully extruding acrylic using a RepRap machine. The problem when working with this material is that when the hot ooze hits the cold air the printed material tends to warp, badly. [Nophead] raised the ambient air temperature around the part being extruded by replacing the bed of the RepRap machine with a heated aluminum plate.

We took at look at his build details for the hotbed. The plate itself is aluminum that he had milled by a machinist friend of his. It looks like the heat is produced by a network of power resistors bolted and soldered to the bottom of the plate. The original idea was to produce a controllable SMT soldering platform. Unfortunately this heating method doesn’t have the power needed to raise the temp quickly but that failure turned out to be a RepRap success.

Powder Coating At Home

January 3, 2010 by Mike Szczys 21 Comments

[j_tenkely] wanted to do his own powder coat painting at home so he built everything he needed, including a coating booth and baking oven. The oven is double walled and built around a frame of steel building studs. Electric oven elements are controlled by a digital control panel and thermostat.

A spray booth is fashioned from a large storage bin. The powder coat gun used in this setup is a commercial project. But don’t fret, this is something you can build rather than buy.

[Thanks goat]

More CNC Goodness

January 1, 2010 by Jakob Griffith 9 Comments

[Jerry] retrofitted a Supermax Mill that he purchased from a friend. The main problem consisted of the original controller failing so he used some Pixie boards and a PC to get the system back up and running.

But thats not all. [Jerry] also retrofitted his Monarch lathe (yes, not a CNC, but are you really going to complain) by replacing the original Ward-Leanard motor generator with a 2 kW brushless AC servo.

The Harford HackerSpace group claims their CNC can kick any other CNC’s butt! Currently it lifts up to 65 pounds, but is still accurate enough to make ninja throwing stars. The only problem left is naming their CNC, any suggestions?

[Ciric] has finished up the hardware side of his CNC project. However the software is still being worked on, but because it is his own stepper control board it might take a while. The good news is the controller and software are planned to be released free.

Old Equipment Repository

January 1, 2010 by Mike Szczys 6 Comments

[Swake] tipped us off about a collection of old equipment. The site is packed full of various hardware that was used for electrical and chemical testing, metering, and experimentation. You could use this to identify the dinosaurs found in backrooms of college science departments, or draw inspiration from it. The next time you’re laying out a panel, or working on a steampunk-ish project go to the source to achieve that vintage look. Some of these remind us of the control panel on [Steve Roberts’] bicycle.