i read elsewhere in the forum that kevlar bands are not very kind to the drums if you are an inexperienced t driver. is this true ? and if so, why ?
LOL not again!
I have had cotton, Kevlar, and wood bands.
They all worked.
I like the feel,of the wood bands best.
It might be do to other things but it is wood for me!
Get someone to teach you how to drive you T properly and you’ll never have to worry about which bands you have. Let the engine slow the car down .. and only use the brakes just before stopping. Also make sure your pedals are adjusted properly.
Kevlar is five times stronger than your drums. It's your choice if you want to subject the drums to that kind of abuse.
I love my Kevlar, that being said, its probably good advice to start out with something more forgiving like cotton until you master driving it properly and feel comfortable in your abilities to minimize band slippage.
Vincent, its how much pressure your foot apply's to the pedal that will cause any band to do its evel deed. if you do not press hard enough to stop the drum from turning your wearing the lining, wood and cotton are more forgiving to the drum, kevlar is a much harder materal and will heat the drum much faster and score it. what you need to do in starting off allow your car to get under way,and within a few feet push hard on the pedal so as to stop the drum from rotating, this will give full power to the rear wheels and wont slip the band on the drum. think of taking off in your standard transmission car, you in that action slip the clutch to get under way and let the pedal all the way out so your not slipping the clutch.on the T you slip to get moving a few feet then press down hard to stop the slippage, it takes some practis to do this in a T but you can do it. enjoy the T .GREG
I found run them little looser and firm pedal push.
Dont let them slip
When comparing "strength" it is typically compared to yield strength or ultimate strength.
Ultimate yield strength of Cast Iron ASTM A-48 is 200 (MPa) vs:
Copper - 220 (MPa)
Brass - 550 (MPa)
Human Hair - 380 (MPa)
Bamboo - 350-500 (MPa)
if Kevlar is 5x stronger than Cast Iron...big deal. Lots of stuff is stronger than cast iron and a lot of them are things you'd never imagine. There is more to it than "strength".
Ask Dave Huson about the myriad broken drums he's torn down that came from transmissions that have only seen cotton bands.
Kevlar doesn't break drums. Heat and/or age break drums. Kevlar as are ALL linings are simply the source of that heat. Therefore, limit slipping, you limit heat.
Moral: Take Mark's advice on driving lessons and then don't slip your bands and you'll be fine (no matter what your lining material).
Ok I will master it
you'll be fine. Welcome to the hobby
The less time your feet spend pressing down on any of the three pedals, the better for your drums and bands. -Take off in first gear with as little throttle as you can without stalling the engine. -At the same time, slip the low band for as short a time as possible. -It'll take some practice to get that technique down, but low slippage and low RPMs are kinder to your drums.
The bands are on the low drum, reverse drum and the brake drum, and your high-gear clutch is pretty much just a regular clutch. -The brake drum can withstand higher temps and friction than the low and reverse drums, but whenever practical and safe, you should behave as though it can't. -On the other hand, if you need to use the brake aggressively to avoid a hazardous situation, for Heaven's sake, do it!
In my humble opinion, the horror stories of kevlar bands cracking transmission drums have been exaggerated quite a bit. -Just treat your century-old car like the antique it is, go easy on her and you'll be just fine. -Accelerate gently, brake gently and go around curves at modest speed. -I learned on kevlar bands and they were no problem at all.
Scott is right. Lots of transmissions that have never seen Kevlar have broken drums in them. As others have said, don't let them slip. A drum that isn't moving isn't being heated by friction, so tromp down on the low or reverse pedals as fast as you can manage it without stalling, and hold them down hard. Use the foot brake as little as possible, braking with the engine and coasting almost to the stop. I help out the foot brake with the hand brake, as those linings are easier to replace.
The only way a drum can be overheated is via the band. So why would anyone use a material that can do just that? The drums were designed to have cotton applied to them. The cotton takes the wear and not the drum. It's completely unrealistic to preach about using the pedals correctly. Replacement bands have been available for over 100 years because drivers wear them out.
My advise about learning how to drive your T properly is regardless of what bands being use. I never minded changing out cotton lined bands with my old speedster. Always took me an afternoon. It had a non starter hogshead and the speedster body was very open. The last time I changed the bands on that car I decided to try Kevlar. There was no real transition since I’ve driven a T for nearly 40 years ... and know how to be kind to bands / drums.
Now that I have a ‘23 T (w/starter motor) with a factory body I can see that it will be much harder to change bands than before. So ... I used Kevlar on this car mainly because I don’t think changing bands every few years will be much fun. I don’t expect any trouble with the drums giving my experience in driving, but I can see the novice burning up drums with any lining if they ride the pedals. So ... it comes back to education. Those of us who know of new T owners in our area should reach out.
I'm wondering if Ford would have used Kevlar instead of cotton if it had been available. There weren't many options back in the day. I suspect he would have, especially if it was cheaper! I have Kevlar linings on all my cars and have never had to replace the bands in any of them, a fact that my back is most thankful for. Anyone who likes changing bands probably enjoys a good root canal too!
Kevlar is a great band lining material, and you can use wood if you wish, the poorest wear is from the Scandinavia tar dipped cotton. What you will enjoy with Kevlar is that it is long lasting, and you won't likely wear it out.
Now for drums, the metal drum lining surface will wear in use, lots of reasons, but mainly due to the engine sharing the same oil with the transmission, as dirty oil contains metallic particles. Those particles are embedded in the fabric linings and that makes for metal on metal wear over time to the drum surface.
So don't worry too much about metal drum surface wear, that will happen. Worry initially about the surface condition of old used drums, that can have sharp edges, and cracks or other defects that shred fabric linings. The drums used should be rather smooth and free of surface issues for long lasting linings.
To show that drums do wear, here is a set of new J&M drums placed in my '27.
Now with new drums I figured wood linings would be good, so installed Gwinn lined bands.
Then after approx. 6,000 miles, inspection showed the low band with much wear, the other band wood linings not much, as this T has Rocky Mtn. brakes and the brake band wasn't used to often.
Wood lined bands after removal.
But also note the condition of those brand new J&M drums, there is metal wear patterns on the surfaces, esp. the low drum, as the trapped old oil and metal and debris in the oil is contained and pressed onto the drum surface. That will happen with all linings, its the nature of the shared splash oiling system. So, choose a lining you like, the Kevlar replaced the wood in my '27 and no change in smooth operation was noted by change of band linings, this is my experience, others may differ, but IMO, Kevlar lasts the longest and saves you from replacing linings sooner.
Model T's are not indestructible.
When a person in today's world starts learning to drive a T he's already got lots of experience driving today's modern vehicles.
Gear jammers and folks with a heavy foot can tare up a T transmission in a hurry and the first things to go will be the drums. Once a person understands that Model
T's are vehicles with 100 year old technology their breakdowns will be minimal.
If you think cotton running in dirty oil cannot wear out a drum, you simply are new at this or in denial. This is the very basis of the process of lapping material: a softer material impregnated with something abrasive will wear the daylights out of the harder material it rides against. I know you believe the forum doesn't care for facts; you've said it many times. This is a fact.
Despite this being your cause de celebre and about the only thing you will comment on in the forum, I expect you will not be able to let this go, so I will. I think the OP will be able to read the multitude of sound advice, and then yours, and be able to come to an educated decision for themselves. Good day.
"The only way a drum can be overheated is via the band." Yes. And the presence of so many cracked drums in transmissions that have never seen Kevlar suggests that any kind of lining can do it.
"...folks with a heavy foot..." Don't you want a foot heavy enough to keep bands from slipping?
If you replace the word "rock" with "band lining" it's perfectly analogous to the argument being made by the minority.
I agree ... remember when most cars were manual shift in America. People had to be taught how to make positive contact with the clutch pedal and not ride it. Same thing here. A steady pressure applied to to the pedal to make full contact as soon as possible and then maintained pressure while in use gives the longest life for both band and drum. And with brakes ... use the engine to slow down and apply several firm pushes to the pedal to make contact and get fresh oil inbetween.
The simple solution to the enigma is that newbies should stay away from Kevlar, at least until they actually experience a band change and band adjustments.
Then the best practices and the best way to describe Kevlar is the heat is not your best friend. The cause and effect that follows heat generation is the bad karma.
1- Make sure the metal support band stays ROUND during installation. You make an “egg” it will make a drag spot when running and unlike cotton Kevlar does not know how to wick heat away through encapsulated oil, or wear away until there is clearance.
2- Do not “feather” a Machine built with Kevlar. “DUMP” those pedals! Pump those pedals! After first contact on compression and surface oil flash off...you have no oil film to wick away heat so PUMP!
3- On install, leave them as loose as possible and then WALK them in over time even if it takes a few times.
Do the above three things, no shortcut and Kevlar CAN be your best friend. Practice on cotton the first time, get educated, then go for a ride with someone who has done more than a few Kevlar jobs
I use all three types of bands on my personal cars. All pretty much installed to all 3 above points. The wood never chirped. They all work equally well, all are driven the same way, and as expected, the first band to go thin was in the heavy Hack, brake band, some old original Scandia I had in a box. Your own experience may vary
Stick with old NOS Scandanavia or traditional cotton linings. You'll get 3 or 4 years out of the brake lining and not have to worry about breaking your drums. You'll get much longer life if you don't live in the mountains like I do. Besides, part of the fun of owning a model T is having to service it now and then.
Scott- you must have me confused with another Tim because I comment on a plethora of subjects on this forum.
The Kevlar issue is stuck in your mind because you are unwilling to entertain any thoughts that are contrary to your own.
Here's a fact for you- I never once said that cotton won't wear out a drum.
you are wrong. Scott is right. stuff a sock in it.
Sorry Helgeson but I'll comment as I see fit. Perhaps some day I'll recognize your authority to pass judgement but I doubt it...
Ok Rogers... Show some of the plethora of subjects you comment on. And please make them something other then snarky mouthy comments. You never have anything constructive to say. If you are looking for someone unwilling to entertain thoughts that are contrary to their own. Just look in the mirror. And yes that is a nice self portrait of yourself in the last post. You are pathetic. If I was to take some ones advise on this forum surely wouldn't be yours.
I have been running K in my T's for years, that has been a minimum of two good mountain tours and a bunch of national tours every year. No problem. I mistakenly put a cotton lined band in once and it came apart.