Reading a Machine

Renata Brenner

The Design• Machine made - stamped/pressed parts/molded• Metal & Plastic (Bakelite) Sturdy• Interchangeable/universal – fits multiple machines• Gears, ratchet, ball bearings• Interchangeable cams –cast• Adjustable

– Interchangeable cams – changed by hand– Bight adjustment – stitch width – depress lever to slide– Cloth clamp – position

• Install w/ screwdriver• Lubricate • Cloth clamp – toothed surface

The Design• Power input is through fork arm – from

needle clamp• Drives ratchet

– Advances material through path determined by cam on needle upstroke

– Moves material back & forth perpendicular to path of needle on needle upstroke

– Stripping arm holds cloth down on needle upstroke

– Holds material stationary on needle downstroke

• Can be advanced manually with knob• Need to cover/retract feeddogs

The Design

What were the designers were trying to accomplish?

What were the designers were trying to accomplish?

• Sewing machine stitches in a straight line

• Create a buttonhole – opening with bound edges (retain shape -prevent fraying)

What is the object designed to do?

Is it part of a system?

If so, where and how does it fit in?

• Screws onto machine presser bar

• Fits onto needle clamp

What is the expected input and where will its output go?

• Device holds and moves fabric in synchrony with the sewing machine needle in order to create a buttonhole

Who would use it?

What they were assuming about the people who would use it?

• Knew how to sew

• Read instructions/diagrams

• Use a screwdriver

• Reasonably mechanical

What is that person expected to know?

• Parts and Functions• How to perform basic

tasks with the sewing machine

What is she or he supposed to be able to learn?

• How to install

• Position/adjust

• Choose thread/size/style based on fabric/button

• Adjust width

• Maintenance: open & lubricate

Phylogeny

Sew Long!