WKTaylor
Well-known member
- Sep 24, 2001
- 4,094
I have a dilemma. Anyone... ?
Our turbine engine has fairlead blocks [for soft-capturing/holding tubing and wiring], made from NBR Rubber Shore A70+/-5 hardness.
On the Fairlead drawing, the preferred fab method is by rubber-molding: however it is optional to make [machine] them from thick rubber sheet... which seems like a valid option... except...
I have directed machining for most metals, a few ceramics, various plastics [various nylons, PTFE, etc] and various Fiber Reinforce Plastics [FRP]. However, I can't find anyone or any corporate experience or written guidance for machining slab rubber, such as: cutter geometry [teeth, angles, twist-angles, blade cut geometry/sharpness, etc], cutter-speeds, feed-rates, lubricant-flow, cooling, etc.
The only ideas that I could add to 'maybe' simplify the machining of a slab of rubber is to:
A. Chill the rubber block the to sub zero [but not below the brittle point] so it machines more like hard plastic. NOT sure of this possibility... just a SWAG.
B. Machine(a) ~80-to-90% thru on one-side; or (b) ~40-to-45%thru from both sides [mirror images].... then knife-cut-thru the thin remaining thick web to separate-out the intended part.
This logistics problem... no spares for almost a year and none 'due-in' in the foreseeable future... has become a [my] 'engineering problem'. Machining from readily available rubber slab material appears to the '$1M wraskley wrabbit' answer... if feasible.
Please advise!... quickly.
Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]
Our turbine engine has fairlead blocks [for soft-capturing/holding tubing and wiring], made from NBR Rubber Shore A70+/-5 hardness.
On the Fairlead drawing, the preferred fab method is by rubber-molding: however it is optional to make [machine] them from thick rubber sheet... which seems like a valid option... except...
I have directed machining for most metals, a few ceramics, various plastics [various nylons, PTFE, etc] and various Fiber Reinforce Plastics [FRP]. However, I can't find anyone or any corporate experience or written guidance for machining slab rubber, such as: cutter geometry [teeth, angles, twist-angles, blade cut geometry/sharpness, etc], cutter-speeds, feed-rates, lubricant-flow, cooling, etc.
The only ideas that I could add to 'maybe' simplify the machining of a slab of rubber is to:
A. Chill the rubber block the to sub zero [but not below the brittle point] so it machines more like hard plastic. NOT sure of this possibility... just a SWAG.
B. Machine(a) ~80-to-90% thru on one-side; or (b) ~40-to-45%thru from both sides [mirror images].... then knife-cut-thru the thin remaining thick web to separate-out the intended part.
This logistics problem... no spares for almost a year and none 'due-in' in the foreseeable future... has become a [my] 'engineering problem'. Machining from readily available rubber slab material appears to the '$1M wraskley wrabbit' answer... if feasible.
Please advise!... quickly.
Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]