Cutless and cutlass bearings

vyv_cox

vyv_cox

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Now retired, anchor swallowed.
coxeng.co.uk
Several recent questions about 'cutlass' bearings have prompted me to carry out a little research. Ever since I was involved with this design of bearings in pumping applications I was aware that the correct spelling was 'cutless' but my studies have revealed the following:

When shaft drives first appeared on ships the original water lubricated bearings were made from lignum vitae. At some time in the 1920s a man named Charles Sherwood substituted sheet rubber for this hard wood as an experiment and found the bearing to 'cut less' into the shaft material than the wood did. The idea and the name ‘Cutless’ were patented by Sherwood, along with Lucian Moffit of Akron, Ohio, who produced bearings using this material and design until the company was sold to B.F.Goodrich in the 1950s. For reasons that remain unknown, Goodrich marketed the product with a cutlass logo, creating the current confusion.

Later still, Duramax bought out the bearing division from Goodrich. The tradename "Cutless" is a registered trademark owned by Duramax Marine. The name has become a generic term for them, along with its misspelling 'cutlass'. More properly, and to save confusion, they are 'water lubricated bearings'.
 
Does that mean that anyone who has fitted a Cutlass bearing should remove it and fit the correct type? Clearly they are rip-offs named to avoid the registered trademark.

:)
 
I have always thought ‘Cutless’ correct because I read it thus first, and so despite being something of an etymological enthusiast I never tried to nail it down as you have done. Thank you - most satisfying to have the full explanation.

I guessed that Goodrich thought that the ‘Cutlass’ logo was a good play on the patented name, with marine connotations – it is the sort of thing which a marketing department would spot! So thanks, too, to captainboo for confirming that.
 
Well here is a bit more useless information about lignum vitae. (though interesting)

http://mojobob.com/roleplay/weight_chart.html

Uses
Due to the density of the wood, cricket bails, in particular "heavy bails" used in windy conditions, are sometimes made of lignum vitae. It is also sometimes used to make lawn bowls, croquet mallets, and skittles balls. The wood also has seen widespread historical usage in mortars and pestles and for wood carvers' mallets.

It was the traditional wood used for the British police truncheon until recently, due to its density (and strength), combined with the relative softness of wood compared to metal, thereby tending to bruise or stun rather than simply cut the skin.

The belaying pins and deadeyes aboard USS Constitution and many other sailing ships were made from lignum vitae. Due to its density and natural oils, they rarely require replacement, despite the severity of typical marine weathering conditions, and also resisted jamming in their mortise holes. The sheaves of blocks on s........

https://en.wikipedia.org/wiki/Lignum_vitae

Clive Cooper
 
For a time we were involved in restoration projects, village water mills and turbines, the turbines seem to have replaced the wheels around the turn of the 20th century. Then later they had often lain buried and unused in a wet pit for several decades until green energy became the thing toward the end of the century but the lignum vitae bearings were often still intact and working. It was far more exciting to stick a generator on a century old turbine than to substitute one of those modern French ones and the clients and funders were happy to let us do it.
 
Water lubricated plain bearings is what we do, whether pumps, shafts, rudders or submarine dive planes, but composite not rubber. so we never refer to ours as cut anything.

We've moved on from rubber so it's good to have the distinction.
 
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