The two Heavy Duty machines share the same body, so their tables look alike. But one difference matters if you are choosing between them: the 4452 comes with named fits that the 4423 does not have. The method page explains what the labels mean.
You can find the Singer Universal Hard Case on Amazon, and the trolleys in the Sewing Machines Plus trolley category. Sewing Parts Online stocks cases and trolleys too: its store.
Singer Heavy Duty 4423
Machine size: 15.5 by 6.25 by 12 inches, length by depth by height, machine body only.
| Case family | Result |
|---|---|
| Tutto | Fits by verified dimensions Tutto names the sibling 5532 Heavy Duty, not this model, so this row stays a dimensions fit. |
| Singer Universal Hard Case | Fits by verified dimensions You get exactly half an inch of height clearance, the least our rule allows. It passes. Just barely, but it passes. |
| Everything Mary | Fits by verified dimensions |
| Luxja standard bag | Does not fit under the rule The only family that fails this machine. |
| BlueFig | Fits by verified dimensions Lower confidence: BlueFig publishes dimensions without confirming they are interior measurements. |
| Janome Horizon trolley | Fits by verified dimensions |
| Brother SASEB trolley | Fits by verified dimensions |
Singer Heavy Duty 4452
Machine size: 15.5 by 6.25 by 12 inches, length by depth by height, machine body only.
| Case family | Result |
|---|---|
| Tutto | Named by the manufacturer Sewing Machines Plus names this machine for the Tutto Medium. |
| Singer Universal Hard Case | Named by the manufacturer Singer sells the 4452 bundled with this case. You cannot ask for better proof than the maker packing them together. |
| Everything Mary | Fits by verified dimensions |
| Luxja standard bag | Does not fit under the rule The only family that fails this machine. |
| BlueFig | Fits by verified dimensions Lower confidence: BlueFig publishes dimensions without confirming they are interior measurements. |
| Janome Horizon trolley | Fits by verified dimensions |
| Brother SASEB trolley | Fits by verified dimensions |
The 4452 is the best documented machine we checked: two named cases, from two different makers. If you own one, honestly, you do not need our math at all.