Tuesday, August 12, 2008

Router Table

The Craftsman router table I picked up at a garage sale had an iron top with no real way to mount my router, it probably was designed around some Craftsman router that can be adjusted easily without needing to remove the router. That's probably why it was for sale! The base table is made from salvaged lumber from a headboard. The router table top is just a 3/4" plywood board, replacement for the iron. I routed out a spot to set the router, and a couple of slots to mount the fence. The legs needed a few scraps of wood to screw into, the holes at the tops are horizontal, so they screw into the scraps, then the scraps screw into the top. The wing brackets needed a few new holes, originally they sat a bit higher, because the old table wings were thin sheet, but the center table was cast with ribs that made it thicker. With the new holes they match flush to the top, and the angle of the legs is still the same. Drilled holes on the ends for a screw as well. My router didn't come with a mounting plate, so I glued two pieces of 1/8" Plexiglass together, one of the sheets got a bit of starring where the glue was, I'm not sure if this was a chemical reaction to solvents in the glue, or if it was stress from shrinkage, it seems to be fine structurally, I'll just have to keep an eye on it if it worsens. Hopefully I'll figure lots of ways to put the router table to good use.

Monday, August 4, 2008

Stepper circa 1993

Had a good day shopping at garage sales, there was a community sale where you didn't need to drive very far between stops. I bought a Twain flatbed scanner that has a good 1.8 degree stepper motor, and a base with side rails about 19 1/2 inches (500 mm), the stepper moved a belt that was hooked to the carriage after looping around a geared belt idler. The carriage had a lot of torsional slop though, it only has one horizontal keeper bearing on one side, and the other side has two, forming a triangle, but they are both on leaf springs, so it's free to twist. It'll probably be better to build a carriage than to re-purpose the old one. The stepper has a reducer gear hooked right to the mounting bracket, if I can figure out a way to mount the output gear to a threaded rod it would have very good resolution, there is very little slop in the gears, you can feel the slop a bit by touch, but it isn't visible enough to measure. The scanner also had a power supply that has 5v 2A, 15v 1.5A, +12v 0.3A, -12 0.3A, it's probably good enough to power a few more motors, and it's dead quiet, and slim-lined along the side of the case. This stepper was run from another ULN 2003A Darlington array, though it's a six wire stepper, so it should run from the Stepper Motor Driver 1.1.

Also got a nice shelving unit, so the giant pile of junk in the center of the garage is starting to get a bit smaller as I organize everything, hopefully it will soon all look like I meant it to be that way. It took a while to re-assemble the shelving because of the gravel floor, so it needed attached to the wall despite being a free standing shelf. Plus there was stuff in the way, but now most of that is on the shelves.

And I got a router table, once I get my router hooked to that it'll be a lot easier to build a RepStrap.

And I found some sort of lathe looking thing, If I can figure a way to attach a chuck I'll be able to make the non-printable extruder parts.

Later I salvaged some bearings from a set of inline skates, (14 of them, 2 are bad). The skates are from Goodwill, they had a large pile of skates.

Total cost of RepRap related stuff was $11, though the router table and shelf ran another $20.