Die Filer: Cost $0
A die filer is basically an upside-down jigsaw, which instead of holding a saw blade, holds a file. This machine will be able to do precise filing of intricate shapes without all the hard work of doing it by hand. This will greatly assist me as I find that I can only file or saw for a few minutes at a time now - isn't getting older a ßüĝĝêŕ.
The unit I'm working on is a 35yr old 'Stanley Bridges' accessory, designed to attach to an electric drill, converting it to a jigsaw. Nowadays with jigsaws becoming cheaper, I have upgraded to an 'all-in-one' jigsaw & retired this one.
The materials I plan to use are all scrap, hence no cost. The new file holding head is an old shaft (annealed), grub screw & belt. The pulley was machined from an old VCR part.
Instead of driving it from an electric drill, it will be driven from a small sewing machine motor (much quieter) & vee-belt from an old Singer sewing machine, running on home made pulleys at about 2:1 speed reduction. The belt I'm using is 6mm wide, 4mm deep & has an included angle of 40-degrees.
The original oscillating shaft has been modified, instead of holding a small saw blade, it now holds a file with a shank of up to 1/4" diameter. The files I expect to use will be either old broken chainsaw files or needle files as appropriate.
The new file holding head was machined from a 1/2" Dia. piece of shaft about 3" long. Head about 1" long, neck about 3/8" long & the remainder machined to a tight fit in the original oscillating shaft. The file holding end was step drilled to 1/4" (being sure not to drill too deep & weaken the new shaft), the side was drilled & tapped for a 1/4" BSW grub screw.
The new shaft is held in place by a tight fit, Loctite & the grub screw which originally held the oscillating shaft - having enlarged the indentation so the inner shaft was held, instead of the outer shaft.
The motor I'm using is a domestic sewing machine motor, runs like a dream & has good torque. Of course, the 2:1 speed reduction will roughly double the power available for the file. It will also be speed controlled, using the original controller.
Making a vee-belt pulley.
I will show you how I made the second pulley, the one for the motor shaft. The first thing is deciding the dimensions of the pulley & its vee groove. The piece of steel I am using is a vertical axle from an old swivel chair we scrapped a while back.
This pulley is to be about 19mm O.D., depth of vee 6mm, width at top of vee 6mm, included angle of 40-degrees.
The filer is half made now, more details & photo's will be put on here as soon as they are available.