Trevor Reeves - Artisan: "Pfaffofile"

Introduction

The sewing machine was one of the first industrial machines to make it into the home. With its mechanical cams and levers it is able to produce a range of amazing stitched. By comparison the modern machine is controlled by stepper motors and computer chips and as we all know if something goes wrong they are costly to fix. I am one of the many people discovering the joys of old mechanical machines that were made to last the owner lifetime and beyond. With a little oil and cleaning maintenance these mechanical marvels will last a lifetime and be passed on to ones children

see:Tim Hunkin's story of the machine

The pfaff is a mechanical marvel made at a time when appliances were made to last. There are many folk out there who spend their time keeping these machines in good working order. They are known as Pfaffofiles If you are interested the Old Pfaff Forum can be found. you must register as a member, but the collective knowledge is unequaled

My Pfaff 260

My Pfaff 260 was purchased a few years ago as a back up to a Pfaff 1222e. It came from the original owner, that was given to them as a wedding present and in that time it was virtually never used maybe the occasional pants cuff altered or the hemming of a curtain. The were no marks or scratches. a good buy at $30.00 AU The quality of the stitch for applique is unsurpassed. and only my Necchi Supernova comes close. It I have any complaint about the machine it was that for the type of sewing I do needle up/down is important as is knee lift of the presser foot. The 1222e dose not have these functions and I have an industrial machine for this type of work, however the industrial machine has had a hard life and is difficult to keep in adjustment, so the decision was taken to install the Pfaff 260 into the industrial table. This would be a bonus as the attachment for needle up/down could be done by a simple coupling on the hand wheel of the machine. With all the fittings for a knee lift in place my over active brain started to see the possibilities of a knee lift attachment.

Material required.

1m x 5mm silver steel rod also known as drill rod
4mm grub screws
15mm free cutting stainless steel shaft for bearing housings and thrust washers
1/16 mild steel plate
5mm id x 11mm od x 6mm wide sealed bearing for the lift arm
5mm rod end bearings

I have an extensive workshop so machining parts is no problem. I have tried to keep the attachment as simple as possible.

Modifications to the machine (These need to be reversible or of only minor significance)

Hand wheel the suit M series V-belt
hole in bed of machine drilled & reamed from 6mm to 8mm
An extension to the lift lever of 20mm
slight reshaping of the casting around the lift bar to accommodate centralization of the new lift lever (minimal)

Inspecting the machine

On close inspection there are several holes located to the right places for this attachment and I wonder if there ever was a knee lift attachment for this machine.

Setting up the needle positioning sensor

Note the hand wheel was modified to take a standard M series V-belt the coupling for the position sensor is attached to the lock nut of the flywheel as loosening for winding the bobbins is no longer necessary. The coupling shaft is held in place using 6 x 4mm grub screws, it is important the these two components run concentric to each other to avoid any wobble.

Will it all fit

The proposed bearing housing for the lift shaft was determined by the location of the 3 hole in the back of the machine these normally have plastic plugs or inspection covers

The hole near the lift bar is the access to the needle bar screw The middle hole is a tapped 8mm thread the function of which I am unsure. The one on the left is access to another adjusting screw.

The left and right holes are parallel to the machines bed, perfect for running the lift shaft. This position makes the attachment an easy fit.

Checking the position of the bits......will they fit?

Linear motion is transferred to rotational motion via a short crank

The lift shaft bearing in place with the lift rod.

An additional plate was made to stop any flex.

The finished attachment.

Note the 20mm off set lift shaft emerging from the bed of the machine grub screws hold this in place to facilitate adjustment . This fits on to a crank about 40mm long to transfer up and down movement into rotational movement.