Different type of shaft key (Dutch Key)

[thehomeengineer]

Hi All

This is the method I have used on several projects to lock a nut to a piece of studding or a plain collar to a shaft (If placed at the end of a shaft) etc. I used this method to lock the wheels to the axles on a 5" gauge loco I built. It is easier than broach, cutting a keyway and then having to make the key as well as then having to drill and tap a hole in the coupling or collar to prevent it from sliding along the shaft. Not only does it secure both the nut to the studding not allowing it to move but it also creates a good drive key. The key is a grub screw which fits into a tapped hole drilled on the centreline/edge of both the shaft and nut, See photo.
I am sure there will be a few of you who can take advantage of this simple and quick method.

Please note that if you are putting a lot of torque into a shaft I would advise you use the correct key for the shaft diameter being used and not this method.

Thank you again for taking the time to view
The Home Engineer

[DIYer]

Thanks thehomeengineer! We've added your Dutch Key to our Miscellaneous category,
as well as to your builder page: thehomeengineer's Homemade Tools. Your receipt:

Dutch Key by thehomeengineer

tags: locking

[Toolmaker51]

Your 'Dutch Key', we call them screw keys but they are prevalent in many types of machinery.
They appear on light to medium load shafts and especially handwheels. Why handwheels? Because there usually is a panel behind, with shafts supported farther inboard. So any inspection or repair progress is hindered minimally in removing panel, handwheels reattached for adjustments etc.

[jjr2001]

Nice idea, never seen that before. Seems like every day I find more tips and techniques here.

Cheers, JR

[ncollar]

I think I will be trying it very soon. I have a 5 inch 1 inch thick steel disc I will be putting a shaft into real soon.
Nelson

[tonyfoale]

I have often used this technique but I never knew that it had its own name, Dutch Key.
In order to ensure a balanced load between shaft and housing I often use 3 screws. Of course it also increases the torque capacity. Instead of the obvious 120 deg even spacing I always offset one screw so that it is say 110 and 130 deg from the other two. This ensures that if it has been disassembled it can only go back together as it was.

[Toolmaker51]

I have often used this technique but I never knew that it had its own name, Dutch Key.
In order to ensure a balanced load between shaft and housing I often use 3 screws. Of course it also increases the torque capacity. Instead of the obvious 120 deg even spacing I always offset one screw so that it is say 110 and 130 deg from the other two. This ensures that if it has been disassembled it can only go back together as it was.

Good point tonyfoale. Equally spaced holes can be difficult to re-insert fasteners of most any type. Especially threads where the helix of each half become individuals when out of the original phasing.
I'd recommend readers alter the spacing as you mention, or at least indicate correct position with pip marks.
It also helps where shaft or hub have some type of shoulder registering the axial position...

[tonyfoale]

It also helps where shaft or hub have some type of shoulder registering the axial position...

One of the advantages of the Dutch Keys is that when you don't have a shoulder the axial location is tied to the thread, at least within the pitch of the screw and it is usually obvious if you are a pitch or more out of position.

[Toolmaker51]

One of the advantages of the Dutch Keys is that when you don't have a shoulder the axial location is tied to the thread, at least within the pitch of the screw and it is usually obvious if you are a pitch or more out of position.

Perfectly true Tony. I'd point out that difficulty isn't prevalent in careful work.
We find Dutch Keys/ Screw Keys infuriating when the drilling and tapping was not so carefully done. Most often is substitution of tap drill sizes, and/or whether drilling - tapping were held within decent perpendicularity. I suspect many hand done with a portable drill, which also means hole centerline may not be precise junction of shaft and bore.
The shop joke was "that machine is impersonating so and so, [a mechanic] sounds just like him!".
One soon leaned to punch mark orientation BEFORE teardown.

[rasta]

I have often used this technique but I never knew that it had its own name, Dutch Key.
In order to ensure a balanced load between shaft and housing I often use 3 screws. Of course it also increases the torque capacity. Instead of the obvious 120 deg even spacing I always offset one screw so that it is say 110 and 130 deg from the other two. This ensures that if it has been disassembled it can only go back together as it was.

Hi Tony; I have fitted many of them to shafts in the industry, here in OZ are called Scotch keys?