Messages : 232
Sujets : 36
Inscription : Mar 2013
2013-11-26, 18:43
(Modification du message : 2013-11-26, 18:46 par Oran.)
Drawings explain far better than words.
I’m much more optimistic about finding traction fluid now that I know it doesn’t contain any metal particles. I always thought the fine powder was meant to be there and it was just the larger particles that weren’t. Santotrac 50 is looking much more promising.
- Oran
Messages : 876
Sujets : 102
Inscription : Apr 2010
2013-11-26, 20:11
(Modification du message : 2013-11-26, 20:12 par Normand_Nadon.)
If you could put your hand on a densidometer and a viscometer (can be found for cheap or borrowed) You could determine the closest match with santolubes...
My guess is that it will be like Santotrack 32... The 50 formula is for food plants... The 32 formula has enhanced anti-corosion additives...
-
Si ça a déjà été fait, je peux le faire
Si ça n`a jamais été fait, donnez-moi juste le temps de trouver comment !
Messages : 876
Sujets : 102
Inscription : Apr 2010
And don't forget, Fallbrook invented the hub, but surely not the oil in it! They probably built the hub around the specs of the fluid, not the other way around.
-
Si ça a déjà été fait, je peux le faire
Si ça n`a jamais été fait, donnez-moi juste le temps de trouver comment !
Messages : 232
Sujets : 36
Inscription : Mar 2013
2013-11-28, 20:26
(Modification du message : 2013-11-28, 20:27 par Oran.)
I was under the impression that Fallbrook did have some input into the development of the traction fluid. I’ve just found the name of it which I noted down a while ago as Valvoline's INVARITORC 638. I have tried a search and got nowhere with finding any specs.
Tracking down this oil may not be possible but I think it will be more fun to find an equivalent. Then we can find out if all the talk about Fallbrook’s oil working at lower clamping pressures is in fact true.
I’m not very clear about what specifications really matter when it comes to traction fluids. Coefficient of traction is obviously an important one but is there anything else that matters.
- Oran
Messages : 232
Sujets : 36
Inscription : Mar 2013
I thought I would take a different approach towards finding suitable traction fluid. As I can measure the components inside the hub I can in theory calculated the required traction coefficient. What’s of importance for this is the angle of the ramps on the backs of the traction rings. It’s the ramps that create the clamping pressure from the input and output torque.
The angle of these ramps is 7 degrees and using basic trig this means the clamping force will be 8.1 times greater than the force exerted by torque. The resulting traction coefficient required is 0.12 or greater. Unless my calculations are wrong this means it is a bit above that of the traction fluids I have come across. Santotrac 32 averages 0.1 and Idemitsu TDF (Traction Drive Fluid) is 0.07 – 0.09.
- Oran
Messages : 876
Sujets : 102
Inscription : Apr 2010
Told ya... Santotrac 32!!! Maybe you can ask for perticular additives to add in the mix to avoid deterioration of aluminium and other soft metals in the hub.
-
Si ça a déjà été fait, je peux le faire
Si ça n`a jamais été fait, donnez-moi juste le temps de trouver comment !
Messages : 232
Sujets : 36
Inscription : Mar 2013
I’m concerned that the traction coefficient of the oil needs to be higher than the traction coefficient generated by the hub. Doesn’t this mean that the traction fluid needs a coefficient of traction of around 0.13 – 0.14. Meanings it’s a bit beyond most fluids available and suggests Fallbrook have managed to lower the clamping pressure.
- Oran