MTFCA Forum

This is a great post from the old forum I think would interest those that have not seen it.



By Kohnke Rebabbitting on Saturday, July 20, 2013 - 07:01 pm:



The Brake drum was shot, so we ordered one from J&M Machine, Oh, what a Beauty, in every way.

I started taking pictures today, and will add more as I progress, as if I wait, it will take a long time to get them all listed.























































This is a Jig I made, to align Ream the Tail shaft bushing, as out of Ford Service.



Align Reaming Tail Shaft Bushing



Triple Gear Reamer, Wilson Benches coming. First one is a starter and Gen. table, I have Two.









Showing Reamer Finish.





Parts Ready to Machine





























Pictures Showing Dial points







Showing center Point that was making the shaft off center, I cleaned it up, and it centered



Hose clamp to hold the fingers back



Centering brake drum in 4 Jaw









Brake drum, Tail Shaft, and also Main shaft now in perfect Alginment



Got the Triple Gear pins in the mail today, and have to polish out .000-50 thousandths on the bearing part of the pin.

I will have to take .001 thousandths off the part that press's into the flywheel.

That will leave a .003 thousandths press on the pins, and a .003 clearance on the Gear Bushing.



Polishing Triple Gear Pins to size.

The 1.560 is how far back I cut the tail shaft for the Ball cap, no matter if it is ball bearing, or babbitt. This motor will get babbitt.

I will polish out the tail shaft tomorrow, and cut the ball cap.











By the way, that clamp and switch is my automatic shut off switch.







Polished, before polishing



Can still see the lines after the 1500 grit, but can't with the finger nail.



Aligning the ball cap at the only place that comes close to the center every time.













Ruffed out babbitt at high speed, .020 left to go.



If you want something that gets right to the 1/10 of a thousandths every time, these are what will do it. They are call inside Mic's, or also Post Mic's.





Putting in the oil groove.











Made for pressing out the pins, but normally I just take a big hammer and knock them out.





I oil the pins. I use a dead blow to tap them in.





I use 1/2 of a Model T wrist pin to push the pin to level.





I use 1/4 inch coarse X 2" bolts and tap the flywheel.



My boy made this to use flywheels on.



It goes up, down, and turns so you can work on the Magnets, or what I am doing.







I hold a big hammer under the bolt to take the stress of the threads when peening.



Small taps, no big hits.













Oil the inside of the gear and shaft





















A couple of things here.

After you press on the driven gear, it just about always makes the brake drum bushing go smaller, and from the two keys pushing in on the bushing that you should always run the reamer through again to size the hole where it was.



The other thing is the clutch spring pin should be cleaned up so the pin can be placed by hand, instead of having to pound it in.





Band Building

We media blast, "Black Diamond", no dirt, make sure there is nothing caught under the end that is riveted on. clean, clean, clean.





As they come out of the box.



I mark an inch.



I use a metal shears to cut the 1 inch off.



Cut off.



What I use to seal the ends from raveling, way better then what was on them out of the box.





I spray on a slick paper, so it don't soak in so fast, or wax paper.



3 Pieces cut in 1/2.



This is two coats.





K.R. Wilson rivet machine.











Check to make sure bands match drums.



Rivet seated on the inside.





The ends of the bands out further then the band ears, so they don't gouge the drum surface.







Transmission assembly:





























































By Kohnke Rebabbitting on Sunday, July 21, 2013 - 03:40 pm:

I always check the drums with expanding mandrels to see where the out sides are with the center, and that is with out bushings.



The first time I knew the center was right, as I check, and recheck, and found out with the mandrel, that the drum was sprung a little, and that is a waste of time, and bushings.



If the drum is sprung, which isn't too often, but happens, I pitch the drum.



The drums that the out sides were cut, or out of round with the center, they do go in a 4 Jaw, and get the bushing shaft with gear centered and bored to within a .001



Then they go in the Wilson jig and centered on the reamer taper, locked down, and the last .001 is reamed with the hole, and Jig.

The out side band area does not touch, or do you want it to.



I have had I think 3 re-rebuilds that I had to do this way, other wise, its normal.



Then the out side is trued again, and no I don't have to take off a 1/4 inch.



Thanks Herm.



By Kohnke Rebabbitting on Sunday, July 21, 2013 - 05:50 pm:

I have almost 3 sets of reamers. Two sets were were N.O.S..



So far I have used both sets, and sharpened both sets once when it gets time.



Counting just transmissions, I should have done about 350 to 400.



I don't use them dry, as I use cutting oil on the bushings.



You have to check the reamer under a big Mag. Glass, to see if there is any reflection of light of the edge that cuts. If there is, that's the time to sharpen, or you can ruin the reamer.



When you sharpen a reamer, they only sharpen the taper part, if they have to sharpen the side, they some times can do it once, a very little, or the hole size gets smaller.



While they would still bore straight, you would have to finish with a hone, or a different reamer of some kind.



By Kohnke Rebabbitting on Tuesday, July 23, 2013 - 11:24 pm:



The first drum had .018 thousandths taken off.

The second one, .011-50 to .012.

I would have taken more if needed.



To just polish a pitted, wore, and warped drum O.D. is not rebuilding.

High and low spots on drums give bad band surface. It seamed important enough when they were new.

I have always turned the drums, and would never put a Transmission together with out it.



They were rust pitted, and the drums are just about always not true from band wear.

Trueing them makes them round to the center, and a 100% band contact.

To me, with out Trueing the drums would be like putting on New brake shoes, and not true the drums, that makes every thing New again.

The only drum I didn't turn was J&M Machines New brake drum, as it dialed Zero.



By Andre Valkenaers on Thursday, July 25, 2013 - 02:06 am:

Herm, Why do you use only one bushing on the brake drum??



Thanks Herm



Andre

Belgium



By Kohnke Rebabbitting on Thursday, July 25, 2013 - 01:12 pm:

Andre, I leave them out because they are not needed. Ford left them out in late 1925, and later.



The only way the oil gets into the Brake Drum bushings is the hole in the Drum shaft, or what can get in the ends of the bushings.



With the inside bushing left out, that whole cavity from the Driven Gear, to the Drive Plate bushing is oiled, and acts as an oil well.



It is also harder to Align 3 bearings, rather than two.



With 2 Bearings you can bore them separate, as long as they are straight with the housings, but with 3 or more, they have to be align Bored, or align reamed.









By Chris Brancaccio - Calgary Alberta on Thursday, July 25, 2013 - 02:32 pm:

Herm, do you balance the drums?



How is the balance on the new J&M drum?



By Kohnke Rebabbitting on Thursday, July 25, 2013 - 03:33 pm:

Chris, We have the drums Balanced if the owner wants it.



But we always balance the Flywheel.



We have had only one Balanced from J&M Machine. It was off a little, but so are the Originals, and a lot more. They sure have the Originals beat by far. I don't think you could cast a piece like that and get any kind of balance.



Every thing is balanced from the wheels on out modern car to air craft parts.



By Stephen D Heatherly on Thursday, July 25, 2013 - 10:07 pm:

Herm, do you always replace all the bushings or just the worn out ones? I have heard several times that replacing the bushings makes for a noisy transmission but, I would think as long as everything was done right there would be no problem.



Stephen



By Kohnke Rebabbitting on Friday, July 26, 2013 - 12:42 am:

Stephen, I have never taken a Transmission apart, that was good enough to just clean up, and put back together, for my own, or a customer.



The transmissions will run wore out, if not to bad, as will the rest of the motor.



The problem comes in when the bushings wear to much, and then start taking out the gears on a drum, or triple gear that could have been saved.



If the triple gears are left go to long, with .004 thousandths, on up, and as all triple gear pressure is to the outside, the gear will run tipped on the shaft, and the teeth will eat into the flywheel, and ruin the gear surface, and or the flywheel.



As far as the noise, I have never heard one any different then another, outside of the ones that need fixed.



If you have grinding, scraping, knocking, ect., something was over looked.



Many transmissions are left with the old triple gear pins. A typical triple gear pin is .002 thousandths out of round, and it is always on the high pressure side on the gear. So, if you fit the new bushing with .003 to the largest diameter, with wear of .002 at its lowest, now the clearance is .005, and the triple gear has no choice, but to run cocked.



So, when the triple gear runs cocked, it will tear up the teeth on the driven gear, and the drums.



The last thing, when I get time, I will take some Mic readings on my N.O.S. drums and triple gears, as they are factory reamed, and that should put to rest the difference of opinion on what the clearances should be, as these will be Ford factory Spec's.



By Andre Valkenaers on Saturday, August 03, 2013 - 01:36 am:

I just Wonder:

Why do you cut the band lining in half and are you leaving a gap in the middle of the lining? Is this for a better cooling and oiling of the bands??

What is the red stuff you add on the bands at each end??



This real a great writing and should be saved in a manuel.

Thanks



Andre

Belgium



By Kohnke Rebabbitting on Saturday, August 03, 2013 - 01:03 pm:

Andre, I read about the band lining method in a Dykes automotive book when I was a kid. It made sense, so I have always done it that way.



It leaves a one inch gap at the bottom for oiling.



With out the stiffness in that missing band area, the band is left to be able to flex more so all the band will contact at all the band, not just some areas.



The bands as they come out of the box do not have enough goop on some ends to keep them from raveling.



There is already a picture of this, but this is red electrical insulation paint which I get at an electric motor shop.



Thanks Herm.


Jason Walters

Interesting info.
Thanks
Rich

Herm.....I want to personally thank you for taking the time to document and share your techniques for transmission rebuilding. It is greatly appreciated.......John Jackson

What a wonderful series of pictures, thank you so much.

That looks wonderful. If it runs as good as it looks, it could be in service for another 100 years!
Norm

Very nice tutorial. Thank you. I've never seen transmission linings done that way before. Does anyone else do this? How had this secret alluded me for 40 years?
: ^ )
Keith

KWTownsend wrote: ↑

Wed Mar 13, 2019 12:44 am

Very nice tutorial. Thank you. I've never seen transmission linings done that way before. Does anyone else do this? How had this secret alluded me for 40 years?
: ^ )
Keith

I read Dad's Dyke's book, when I was about 14, it sounded like a good idea, as the bands that we replaced were never wore even. It seemed like the sides were, and the bottom wasn't. So it looked like a cure, and in my opinion it works very well.

The normal way of putting on bands, you have one gap at the top to dump oil in the whole band, clear around. With a gap at the bottom, it also dumps oil in the second gap. So now to me, the gap at the top oils 1/2, and the gap at bottom, oils the other 1/2. The bottom gap also lets the band fit it's self better to the drum, when it can flex.

Herm.

Nice to see you back Herm

All I can say is just WOW ! Looks a lot more precise than Henry ever did.
Thanks for sharing.

Herm , hi ..i like your style ..if i was to bring
an average 1913 transmission for rebuild to you ..what would it cost approx these days ?...
im talking new drums and seals, t 400 clutch plates ..cheers johnny

Johnnybuick wrote: ↑

Fri Mar 15, 2019 7:27 am

Herm , hi ..i like your style ..if i was to bring
an average 1913 transmission for rebuild to you ..what would it cost approx these days ?...
im talking new drums and seals, t 400 clutch plates ..cheers johnny

I am sorry Mr. Johnny, at this time, we are about 4 and 1/2 months out with just babbitt work. Most of our work is for other machine shops that are engine builders. I keep telling them of our time frame, but they just keep sending bearings, and I never know what is coming in from, day to day, they just send them, and it has been that way for years. We don't do T, A, or B Rods any more, as ours are spun poured, and there isn't any money in them, as we have to premachine the rod cores, before Babbitting. We still babbitt a lot of Blocks, and all other cars and tractors.

Thanks,

Herm.

Jason, I have replaced six sets of the modern disc this past year, I have never replaced burned up steel ones, maybe they work for some applications but they will not go in my cars, thanks any ways!

Superb post Herm. Thank you! Cheers, Bill

Herm is unable to comment unfortunately.

Joe Bell wrote: ↑

Wed Feb 05, 2020 7:43 am

Jason, I have replaced six sets of the modern disc this past year, I have never replaced burned up steel ones, maybe they work for some applications but they will not go in my cars, thanks any ways!

Agree 100% Joe!!!!

Just replaced a set a few weeks ago with stock plates. It's a great idea, but the lined plates simply cannot survive any slippage.

I'll be having Joe replace a modern set in my Torpedo after this season is done. Back to stock!

It is a given that any material softer than steel will wear quicker. How long have the modern discs lasted in some of your builds?

Wonder about quality of the 400 disc? Is like everything else from China? Dan

I have over 8,000 miles on 1 motor. All my other T's run them to. The ones I make/modify have been coming from american mfg's? Raybestos when available. Bobs, gaslight & chafins sells them. (speedy T clutch)

400 clutches & kevlar bands "dont suffer fools" require proper set up & can cause damage(kevler) or a pile of rework(400's with a transmission pull) if not.
The rewards are a band that rarely needs adjustment, but engages smooth like cotton bands. (recently did a 2,000 mile trip with no adjustments)
Turbo clutches provide a 100% free neutral (great for a hand cranker) not dependent on warm weather & a solid, positive lock up to high.(Never had to readjust)

Neither can be allowed to "slip"
All the horror stories you have heard are possible.
So it all depends on the owner/driver. If you can follow the "rules", they are both worth it. In my opinion. If you cant, neither is for you.

FYI, if new drum(s) are needed, Drums made by Dave Nolting of Dave's Restoration and Machine are a much better choice in my experience.

They are CNC machined from ductile cast iron and require little, if any, balancing.
Oh, and the best part is Dave's drums will save you around $750 for the full set with gears. That's a Win-Win.

More information available here: https://www.davesrestorationandmachine.com/

I agree 100% with speedytinc, I've lost count on how many modern clutch packs I've fitted on rebuilds, instruct on how to respect them and never had to replace again. If one can destroy a part that comes out of 150/300+ Hp trans with a 20Hp engine then it's poorly set up or bad driver habits.

So how do you drive these right to save these, and what do you wrong to trash them?

Its more about proper set up & linkage.
The good disks are heavy duty for truck & hi performance applications. The cheap ones are like a cardboard. There are cheap ones out there. Beware.
Chaffis sells the H/D ones & gaslight, Not sure if Bobs still does.

Chaffin pack is 9 disks, standard 8 disks. Typically with the 8 pack , I finish with 2 extra large disks. I want to have the 3 finger screws out as far as possible when assembled. (this is precautionary: if they were to wear there would be room for adjustment. Never happened yet.)

Clutch spring must be strong. A good stock spring will work(100# @ 2" compressed) I use the aftermarket heavier clutch spring & TEST IT. (dont assume a 100 year old or repo part is good.) I expect 110-120#

Throw out bearing is adjusted to a close 13/16". On all my transmission rebuilds,( I grind a 2nd slot in the finger screws for a more precise adjustment.) Then add 1/2 turn to each screw.

I make sure all my linkage is SLOP free before putting the hogshead back on. Set clutch pedal linkage according to T1 manual 1/16". Follow the manual!
Make ABSOLUTELY POSITIVELY SURE the e brake cam completely clears the clutch arm ALWAYS when down. Especially with small drum brakes, they can pull up the brake lever to "slightly" engage the clutch. Bobs once refered an unhappy customer. I asked a few questions & determined: 1)He never read the instructions. 2) Didnt test the spring. 3) Didnt know what a T1 manual was. 4) Didnt know anything about linkage adjustments. But he knew them clutches was no good. I have found this typical of guys that had problems, or bought an unknown T with them worn out.

Driving a stock T, you have a "controlled slip" The proper amount is adjusted for. It makes for an easy transition from low to high when "jumping" off the pedal. With a 400 clutch, you lift off your foot, much like a modern clutch. Its something you get used to. Too fast, it jerks, to slow it slips. The slip wears out a 400 clutch. Realize, in a modern transmission, lock up is fast & solid with a lot of hydraulic pressure to maintain lock up.

I have been running them in all my T's as far back as I can remember. One set has over 10,000 miles. @ about 5,000 I had to pull the motor. There was NO measurable wear, so I reused them. Never had to adjust any of them.

P.S. Just realized, I forgot to mention the brake drum clutch lugs cant be "notch" worn. This can cause hang ups & slippage just like with stock steel disk setups.
I have pretty much used the replaceable lug drums & cutting them down for narrow brake applications.

Original steel disk clutches had a dish to the inner disks. They would release & work well when new. Once they lose that dish, they became unfriendly to cold weather disengagement. Some guys have re-dished them with good results. Parking with the e brake down helps also.
I recall a T trip to Bodie where things froze overnight. That morning 2 of us running 400 clutches started right up. The other 5 had to be dragged to free up their clutches to start.

Danny, the quickest way to trash the plates with bad driving habits is not backing the throttle off between low to high change.

Good information
Thanks guys!

This is the original post by Herm.

https://www.mtfca.com/discus/messages/3 ... 1375578307

For those that don't know Herm passed away some time ago.

Chris

His son (pretty sure it's his son) is still running the business; https://www.facebook.com/KohnkeRebabbittingService/

Excessive slipping of any clutch or band will cause trouble. The T clutch will engage smoothly with practically no wear if handled properly. Some band slippage when starting from a dead stop is unavoidable, but it can be minimized with proper handling of the throttle, spark, and pedals. Obviously, the brake band is going to slip in normal use. Avoid using it unecessarily when other options are available, and release pressure on the pedal briefly during use in non-emergency situations. When driving a Model T, you'd better drive defensively, because you aren't very well equipped to drive offensively.

What about starting it with the park brake on for periods of time while working on them?

As long as the car isn't moving, with the lever pulled all the way back, there's no danger to the parking brake. If you mean running the engine for extended periods with the lever pulled all the way back or half way forward with the car in "neutral", that might cause undue wear on the clutch throwout parts. I'd avoid it unless necessary . The only neutral a Model T has is when the clutch is held out of engagement,which involves a stationary part in contact with a rotating part. It amounts to holding the clutch pedal down in a regular vehicle. Don't do it more than is necessary. Ford advised letting the Model T engine warm up after starting in cold weather before driving the car. That would involve running the engine with the car held in neutral for as much as a few minutes, so it's OK within reason.

Reason for question is running while performing tasks such as tuning on carb, timing, and such.