The hook assembly can be considered the heart of your machine, crucial for timing and stitch formation. Singer did update the design of the hook assembly a few times over the years, and the precision engineering involved means these parts are not interchangeable.
This guide is not only a historically interesting look at the inner workings of your machine, but a useful parts identification guide should you need to repair the hook assembly on your Singer Featherweight.
The diagram below shows the disassembled parts with the corresponding part numbers as well as the complete unit part #45924.
The above photo shows the three Featherweight hook assembly variations with all components.
1933-1934 Hook Assembly:
The first hook assembly for the Featherweight is noticeably different from the others. It was only used from 1933 through about 1934, and was more difficult to disassemble in case of a thread jam. Because it was only issued for a short time, the complete assembly unit part number has not been sourced.
The most common Featherweight hook assembly unit is #45830. It was issued with most 221 and 222 model Featherweights, therefore, parts for this one are easier to source.
The third Featherweight hook assembly unit began appearing on Featherweights manufactured in the mid-1950s, with many of its components being shared with the Singer 301 hook assembly. Unit Part #45924 looks very similar to unit part #45830 assembly, but most of the individual parts are not interchangeable.
Hook Assembly Base:
These part numbers are for the Hook Assembly Base only.
The various hook assembly bases look about the same, but part #45747 has a slightly thinner gib hook rim.
Hook Loop Guard:
The hook loop guard keeps the thread loop from opening too far as the hook passes through. This area often gets burrs and gouges from the needle resulting in skipped stitches. Click here for a video tutorial to learn how to polish this area.
The first two hook assemblies had the #45761 loop guard, but the later hook assembly is often seen with the larger #170128 guard.
Rear Gib Hook Screw:
The rear gib hook screw is one of the two screws that holds the gib hook in place.
The rear gib hook screw is the same for both of the later hook assemblies, but the earlier rear gib hook screw is different. The part # for the early rear gib hook Screw has not been sourced.
Gib Hook Screw:
Each front gib hook screw from the different assemblies have a unique appearance.
There were also three different Featherweight gib hooks.
#45831 and #170160 look almost identical, but the gib hook screw hole is a slightly different shape for each style. The #45756 gib hook has an elongated slot for the gib hook screw; whereas the latter two gib hooks simply had a hole to accommodate the gib hook screw. The early gib hook was uniquely held in place by a spring as well as the two screws.
Because Singer used a spring to secure the early style gib hook in place on the assembly, the entire hook assembly must be removed from the machine in the event of a thread jam. Feel free to contact us if you need assistance with removing or installing the #45756 gib hook.
Bobbin Case Base:
The Featherweight had two different bobbin case bases. From 1933-1935 the #45752 base will have smaller holes, but it is interchangeable with the later #45752. (Singer did not state the purpose of the holes in the base, but we assume they are there to prevent threads and oils from getting completely trapped behind the base.)
Does a UK Produced Hook Assembly Look Different?
The 221K, 221J and 222K machines will have a hook assembly with either a #45830 or #45925 part number. The only variation will be the location of the part number stamp on the base. The photo below shows the stamp for a #170135 hook assembly base. Notice the Great Britain stamp in the photo below:
Notice the USA stamp in the photo above.
Because the hook assembly is such an important part of the Singer Featherweight, we have made several helpful video tutorials for troubleshooting, and they will be linked below. Feel free to contact us if you have any questions about the hook assembly.
How to Fix a Stuck Hook Assembly: https://singer-featherweight.com/blogs/schoolhouse/how-to-fix-a-stuck-hook-assembly
How to Smooth a Burr on the Hook Assembly: https://singer-featherweight.com/blogs/schoolhouse/how-to-smooth-a-burr-or-rust-spot-on-hook-assembly-tension-disks-etc
Timing and Replacing the Gib Hook: https://singer-featherweight.com/blogs/schoolhouse/featherweight-timing-and-how-to-replace-the-gib-hook
Is Your Machine Jammed: https://singer-featherweight.com/blogs/schoolhouse/is-your-machine-jammed