Best lubricant for bobsled runners.

[MeridianDesign]

Hello,

I am conducting an experiment with bobsleigh runners. I'm basically looking for the best type of lubricant to reduce friction between the ice and the steel runner. Should I be looking into greases? teflon? polyurea coatings? What would be the recommendations of some experts in the field of metal and reduction of friction? Any ideas would be greatly appreciated. Thanks all!

 

[IRstuff]

Shouldn't it be some sort of wax, similar to ski wax, if it's some sort of applied coating? However, I don't think that sort of thing would last very long into a run, given the speed and pressure against the ice.

One thing that might be worth pursuing is a ceramic coating. Even the smoothest knife tends to have a "stiction" when cutting meat, but a ceramic knife tends to glide a bit more. Obviously, meat is not the same as ice, but perhaps the effects are similar.

TTFN
faq731-376

 

[Tmoose]

are there some limitations in the rules?

http://www.fibt.com/uploads/media/2012_International_Rules_BOBSLEIGH_clean.pdf

F.I.B.t. says stuff like this
10.8.2 Runners
..........only FIBT standard runners (standard material) are admitted. The authenticity of the runner steel may be controlled by the FIBT Jury and/or FIBT Materials Inspectors at any time. To establish the authenticity of the runner steel,
inspections may include the analysis of the composition of the runner material and examination of the
hardness of the runner steel.....
Only geometrical changes to standard FIBT runners through the removal of the original material are
allowed. No materials may be added in any way....
...........
At the Jury’s discretion, runners can be subjected at any moment to inspection with special equipment.
In case of inconclusive findings, runners may be seized and sent to a specialized laboratory for further
testing.
..............
The runners may be polished between the race heats. Only the athletes belonging to the team from
the sled concerned may perform the work.
.......
The runners can only be polished using abrasives provided by the FIBT
The runners must remain mounted on the sled. The use of any other materials and / or products is
prohibited. Violation of this rule is penalized with immediate disqualification from the race.

 

[EdStainless]

The lubricant is water, the blades must be as hard and smooth as possible. The contact pressure melts a little ice and provides the water.

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Plymouth Tube

 

[dik]

Ed has it... the preocess is called regelation and it's what makes ice skates so 'fast'... the pressure melts the ice forming a low friction fluid surface at the steel-ice interface.

Dik

 

[tomwalz]

All of the above.

It has been a couple years since I looked into this but I seem to recall that the shape of the face of the runner is important. You want to slide on water, not ice. You also need good edges for control.

Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

 

[EdStainless]

There is a guy that come around here that has worked on a runner project before.
Maybe he will show up.

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Plymouth Tube

 

[gearcutter]

"the pressure melts the ice forming a low friction fluid surface at the steel-ice interface."

Otherwise known as hydrodynamic lubrication.
Books about Tribology might give you some ideas.
The best one that I know of is called 'Engineering Tribology' by G W. Stachowiak & A W. Batchelor.

Ron Volmershausen
Brunkerville Engineering
Newcastle Australia

http://www.aussieweb.com.au/email.aspx?id=1194181