Die Filer Project

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.

Old Jigsaw head showing the amount sawn then machined off, plus the v--belt, & the first of the home-made pulleys.

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 home-made pulley & the new file holding head. See details below.

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.


	The body, made from a bit of box channel already welded to the plate. All holes are drilled, milled as shown (ignore marking out lines - pencil). There are 4 rubber feet on the underside. The two large holes are to allow easy access for belt installation & swarf removal. The top plate shows the blocks used to hinge it to the required angle, when in use. The old jigsaw head has its new foot, machined to fit in the end of the box channel - To be fixed with small machine screws.
	Two photo's showing the completed unit - including installed motor.
	The slots in the side are to allow access for tightening the pulley locking screws.

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 piece of steel is first turned down to its final O.D. for the required length (plus a small amount for parting off), 19mm x 30mm.
	Using a H.S.S. tool ground to just a bit less than the width of the bottom of the groove, with relief on each side, the deepest part of the vee is turned down to, in my case, a depth of 6mm x about 3.5mm wide. The cutting tool can be seen at the bottom of this & the next photo.
	Setting the compound slide at 20-degrees for each side, the vee is cut, gradually widening until the maximum width was 6mm, tapered for the full depth. I used the same cutting tool, then fine emery cloth to polish.
	The pulley shown after the boss is turned down, step drilled (5mm), parted off, grub screw hole drilled & tapped (3.0mm coarse thread). Here the new pulley is installed on the motor shaft.

The filer is half made now, more details & photo's will be put on here as soon as they are available.