DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
(OP)
We have a transmission that simply will not shift under load. We increase the engine output by 300% and this creates binding in the sequential transmission. The thought came to mind to try and reduce friction on all the sliding components in the trans to help shift quality.
I am looking for real (not theoretical) feedback on DFL coatings to see if they are more of a fluke than actually helpful. I have a hard time believing that a moly coating will be much different than oil with moly in it...
I also posted in the automotive area but thought a metallurgist might have a good explanation if DFL is truly worth using. They say that once the metal has been treated, it soaks well into the metal regardless of appearance. If this is such a great coating, why is it not main stream?
I am looking for real (not theoretical) feedback on DFL coatings to see if they are more of a fluke than actually helpful. I have a hard time believing that a moly coating will be much different than oil with moly in it...
I also posted in the automotive area but thought a metallurgist might have a good explanation if DFL is truly worth using. They say that once the metal has been treated, it soaks well into the metal regardless of appearance. If this is such a great coating, why is it not main stream?





RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
What type transmission is this?
Is this one that requires straight mineral oil?
What the loads on the transmission?
Does it shift when not engaged?
How does the rotation feel?
Before I would go with putting on DFL or polishing gears I would give Lubrication Engineers a call. If you you spin the transmission in neutral for 10 or so minutes with LE oil
and it doesn't shift you have mechanical problems.
http://www.le-inc.com/products.jsp?productID=310
PS:
Don't do like I did a 32 Ford, put the cluster gear in backwards.
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
Who do you recommend to call? Certain office and such? I had a feeling the DFL would wear off quickly and probably just used for race applications where components do not last long anyway. Just seems too good to be true....
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
It sure sounds like something is moving out of alignment under load, which could be anything in the box or the box itself.
I've only seen a few transmissions of this type but worked with what we called a preselector, 5 speed gearbox that had to use straight mineral oil, this was the reason for the question.
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
I would be real interested in building a test to find the flaws or even talk to a prominent sequential engineering company to discuss the issues at hand. My concern is deflection of the shift forks causing uneven stresses on the sliding gears.
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
would seem to apply.
is the housing made of aluminum? are there cut or ground gears. through harden or case harden?
MfgEngGear.
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
Does the fork ends fit in a defined groove\slot that would limit the cross section of the fork?
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
Right now I am looking for some sharp engineers to collaborate with to see if we are on the right track. Sequential just are not that main stream in the US.
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
Are you allowed to rig an ignition/fuel interrupter to kill power just during the actual shift, like the air shifter guys sometimes did?
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
http://www.ricardo.com/
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
I would look to reduce tolerances and improve surface finishes before DFL.
An oil with the right EP additives might help, but if overall distortion of alignment is causing the issue then you either need to stiffen the structure or reduce torque.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
If your gearbox uses dog rings and it's difficult to disengage the dog ring from the gear, then what you likely need to do is regrind the dog faces with slightly less undercut, and increase the shifter dentent spring forces some.
It's the undercut that keeps the dog ring and gear engaged while they're under load. When they're not under load, they can separate since there is generous backlash between the mating dog ring and gear teeth. But the shifter detents keep the dog rings in place when this occurs.
I'd guess that most dog rings have an undercut around 3 to 5 deg. You can probably reduce this to 2 deg without having your transmission jump out of gear, as long as your shifter mechanism is not sloppy.
As for DFL coatings, they can be effective but they only really help when there are marginal lubrication conditions. Your dog rings have three points of contact that produce friction: the dog tooth faces, the spline teeth faces, and the shift fork groove faces. The dog tooth and spline tooth faces are boundary contacts with high contact pressures, so a typical DFL would not likely last long in these areas. The shift fork grooves have constant relative sliding with oil present, so this contact is likely hydrodynamic in nature and would not benefit from a DFL.
Hope that helps.
Terry
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
http://www.remchem.com/
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
Most of the gears in their transmission where super finished.
Addenda:
The transmission was design with a double clutch arrangement. There are two main drive shafts in the transmission one for the even gears and one for odd gears, each with it's own clutch. This allows the transmission to preselect the next gear so they achieve a 150 microsecond shift.
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
I got into a discussion with a burley Harley owner one time, who stated that he had used some oil additive that was so slippery that the tapered valve spring retainers kept popping out. http://www.kmotion.biz/images/Installed.jpg
I did not dispute the statement, at least out loud.
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
Very good engineers on this site & good advice.
I wouls start with the easiest advice and start from there.
Better type of lubrication.
Check for worn parts "shift forks, dogs & gears".
geometry of the dogs " polish & super finish"
less friction.
also verify the edge breaks. make sure there are no sharp edges unless it is critical to have one.
gear teeth .005"-.020" edge break except gear teeth tips .005 max edge break, the tips of the dogs .005"-.015" EB if gear teeath are Case Harden take temper etch & post bake precautions. do not burn or crack.
definetly double clutching "added electronic control"
not my speciality "but a very good suggestion".
stiffen up the structures that hold the transmission
aluminum housing is not helping "just my opinion" twist
are these straight cut gears or helical?
Good luck
MfgEnggear
RE: DRLY FILM LUBE COATING APPLIED TO STEEL TRANSMISSION PARTS
Back 20 years ago I was doing engine/transmission design work on an IMSA GTP car. It was mid-engined and used Hewland VG transaxle internals in a custom case. The single push/pull rod shift linkage ran down the right side of the chassis tub, passed along the engine block just under the red-hot turbo header primaries, and then all the way to the aft end of the transxale housing where the selector rods were. After hard running, the steel push/pull shift linkage rod would get very hot from the headers and would actually grow in length enough so that the transmission could not be shifted properly.
Until we redesigned the linkage, the quick remedy was to bring the car into the pits and douse the linkage with water.
Here's a nifty website with detailed drawings and manuals of racing transmissions:
http://www.hewland.com/svga/down%20loads.htm
Regards,
Terry