a few weeks ago, I saw this great looking old singer sitting in my favorite op shop. it was jammed, and they gave it to me for $7. I slung it over my bicycle handlebars and rode back to makerspace. 

For some time I have been curious about how a sewing machine mechanism actually works, and this discovery of such a old, simple example was an execellent oppertunity! it had no motor, and was very though to turn by the flywheel, so I just took parts off untill I found it was the shuttle which was jammed. I worked each part out, oiled everything, and put it back together... the key part is adjusting the timing of the shuttle (more on this in another post, later)

I made up a wooden hand crank so I could use the machine... It went through very heavy material (bilboard PVC) very nicely. by hand is okay for small things, or when there is alot of time, but not much electricity (for example, on a sailboat) but I wanted a motor!

I found  a cheap plug-in multispeed drill for $25 from the warehouse . I had one of these which lasted 5 years (intill my flatmate broke it, and I'm pretty sure he was doing something stupid with it) I wonder how long it will last as a sewing machine motor? I havn't actually disassembled the drill to use it, and it has a 12 month warranty. (of course I dissasemblemed it! but I saw the the case is integral to the motor -- holds the brushes and bearings in place -- so I decided to put it back together)

1. Table

start by building a table - I made it the same height as the desk, from whatever wood was lieing around. 

then, the that the table of the sewing machine fits flush with the table top, cut a hole for the sewing machine to fit into and put a ledge underneath the stop it falling through. also, cut a slot for the drive belt.

this hole is a little snug, but that works to my advantage and grips the machine tightly. when i want it to some out I just bump it a bit.

2. Motor Mount.

next, make the motor mount. As you can see, the drill is clamped between two pieces of MDF. Each side of the clamp has a hole cut in it over the drill vents to allow for cooling. The drill gets pretty hot if you use it for a long stretch. If you let it get too hot it could melt the case, and you need the case intact because it holds the bearings, gears and brushes in place.

Also, note the the whole structure is on hinges, these attach to the underside of the table and allow the drill to be pulled down, tensioning the drive belt - more on that later.

Also, there is a block of wood on the hinge next to the drill trigger. This will be attached to the foot pedal via a cord. This is how you will drive the sewing machine. Here I am testing the trigger lever:

I am pushing up on the lever, but when installed, this assembly will be upside down, and the foot pedal will pull down on it.

3. Install Motor Mount.

Turn the desk upside down and install the motor mount assembly. Leave enough room so that when you put the drive pulley in the drill chuck it will allign with the drivebelt slot and the driven pulley on the sewing machine. To give the motor mount clearance from the bottom of the sewing machine, I added another beam under the table top, and attached the motor mount hinges to it.

4. Realise you should have made the drive pulley before you installed the motor mount assembly.

to make a drive pulley start by cutting out a bit of 18mm plywood with the holesaw. then clamp the cut circle between two bolts on a bit of threaded rod, so that there is a long end of rod which will fit in a drill chuck. I put this in the drill press, turned it on, and held a round rasp against it to cut a groove to hold the drivebelt. If I didn't have a drillpress I would have held the drill in a clamp.

Later I found the the wood was a little slippery to drive the machine well. you needed loads of tension, and sometimes you had to help the sewing machine get started by turning the flywheel manually as you pushed the drive pedal. I solved the problem by wrapping some bicycle inner tube around the pulley. Make sure you always have some on hand - it's useful for everything!

5. Foot Pedal.

The foot pedal is just a piece of wood with a hinge on one end and a cord on the other. the other end of the cord is attached to the trigger lever on the motor mount assembly.

the bicycle inner tube in holding down the motor mount putting tension in the drive belt.

6. Drive Belt.

I wasn't sure what I could use as a drive belt, so I tried the same type of cord as the foot pedal cord. I just looped it around the pulleys and tied it at what seemed like the right length. It worked! Although, it made the whole motor mount bump whenever the knot went around the drive pulley. Since it was only contacting the drive pulley over a small area, sometimes it would slip. I experimented with putting the rope around the drive pulley twice to increase the friction, this worked, but sometimes the knot would jam on the doubled up section. Then I throught of sewing the cord to itself instead of tieing a knot. It was smooth enough that it always went around the pulley, but I accidentially made it too short to loop the drive pulley twice...

But that was when I discovered wrapping the inner tube on the drive pulley! 

which is also why you the blackening of the drive belt.

now makerspace has a sewing machine!

7. sew something!

I made a new sail for my boat, and then this pack:

it's made from a tarpaulin that I found in a dumpster a while ago. It weighs about .65 kg, according to my friend's kitchen scales, which is pretty light.

right! I'm going tramping. see you guys later!