Connect a Stationary machine 4 in dust port to a 4 in dust-collector hose
How to join a Stationary machine 4 in dust port to a 4 in dust-collector hose, and what stops it leaking dust.
Not a direct fit. Joining the Stationary machine 4 in dust port to a 4 in dust-collector hose needs a 4 in to 4 in step reducer.
Rings drawn to scale from the measured diameters in the table below.
The two ends
| End A | Stationary machine 4 in dust port (3-15/16 in OD, 99 mm OD, 91 mm ID) |
|---|---|
| End B | 4 in dust-collector hose (4-1/4 port in OD, 4 in ID) |
| Fit type | male port into hose cuff |
| Reducer needed | 4 in to 4 in step reducer |
Shop notes
Measured across the joint between the Stationary machine 4 in dust port and the 4 in dust-collector hose, the hose (102 mm) is 3 mm larger than the port (99 mm), so the port rattles inside without gripping. A 4 in to 4 in step reducer closes that 3 mm step so the two hold together instead of leaking at the gap.
A 3 mm mismatch feels close enough to force, and it will hold for a minute before it works loose under airflow. Fit the step ring rather than trusting friction on a gap this size.
The reducer to buy
Search Amazon for 4 in to 4 in step reduceraffiliate searchRelated connections
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