New triple gear pins?

Discuss all things Model T related.
Forum rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules
User avatar

Topic author
Steve Jelf
Posts: 6463
Joined: Fri Jan 04, 2019 9:37 pm
First Name: Steve
Last Name: Jelf
* REQUIRED* Type and Year of Model Ts owned: 1923 touring and a few projects
Location: Parkerfield, Kansas
MTFCA Number: 16175
MTFCI Number: 14758
Board Member Since: 2007
Contact:

New triple gear pins?

Post by Steve Jelf » Tue Sep 22, 2020 12:44 pm

When I took apart my 1923 touring's transmission to replace a busted low drum, I found that one of the triple gears had seized and spun the pin. It wallowed out the hole enough to make the pin wobble quite a bit, so the flywheel is toast. So I went to the barn and picked out a "new" flywheel that looks like it will serve. In reading about installing new pins I read in the Transmission book,
As the holes in the cast iron flywheel become slightly enlarged when the steel shafts are withdrawn, it is necessary to use pins which are .003-inch oversize on the section of the shaft that presses into the flywheel. The use of .005 oversize pins requires that both the hole and the pin be measured and the hole reamed for a .002 press fit.
1 Is the reference to both .003 and .005 a misprint or is it about two different pins?
2 Are the new pins not tapered like the originals?
3 If they are tapered, how do you ream the holes with a taper? Or do you?
4 I assume the oversize is in the part of the pin that presses into the hole, and that the part which supports the gear and bushing is the original .675". Is that right?
5 I've seen different tolerances given for the bushings. How much is enough for the gears to operate with no chance of seizing?
The inevitable often happens.
1915 Runabout
1923 Touring


Jeepbone1
Posts: 596
Joined: Sun Jan 06, 2019 6:10 pm
First Name: Brad
Last Name: Kirtner
* REQUIRED* Type and Year of Model Ts owned: 1924 Touring Car, 1927 Closed Cab TT, 1927 Coupe
Location: Salem, Virginia
MTFCA Number: 50618
Board Member Since: 2018

Re: New triple gear pins?

Post by Jeepbone1 » Tue Sep 22, 2020 12:49 pm

Give Bob a call over at Bob’s antique auto. He’s the one making the new pins. I just installed a set in my trucks flywheel. Nice machining and they installed very well. The end of the pin is slightly oversized to make up for the wear of driving the old pins out.

Brad


Allan
Posts: 5205
Joined: Sun Jan 06, 2019 7:21 pm
First Name: Allan
Last Name: Bennett
* REQUIRED* Type and Year of Model Ts owned: 1912 van, 1917 shooting brake, 1929 roadster buckboard, 1924 tourer, 1925 barn find buckboard, 1925 D &F wide body roadster, 1927LHD Tudor sedan.
Location: Gawler, Australia

Re: New triple gear pins?

Post by Allan » Wed Sep 23, 2020 12:34 am

If the bush seized on the pin and it spun in the flywheel, there was not enough clearance. This is one place where looser is better. I aim for .004"+ difference between pin and gear bushing bore. .005" is better than .003" Others may differ.

Allan from down under.


Jeepbone1
Posts: 596
Joined: Sun Jan 06, 2019 6:10 pm
First Name: Brad
Last Name: Kirtner
* REQUIRED* Type and Year of Model Ts owned: 1924 Touring Car, 1927 Closed Cab TT, 1927 Coupe
Location: Salem, Virginia
MTFCA Number: 50618
Board Member Since: 2018

Re: New triple gear pins?

Post by Jeepbone1 » Wed Sep 23, 2020 1:10 am

Allan wrote:
Wed Sep 23, 2020 12:34 am
If the bush seized on the pin and it spun in the flywheel, there was not enough clearance. This is one place where looser is better. I aim for .004"+ difference between pin and gear bushing bore. .005" is better than .003" Others may differ.

Allan from down under.
I just set mine up with 0.004+ish clearance. Spin like a dream!

Brad


J and M Machine
Posts: 96
Joined: Wed Jan 09, 2019 6:46 pm
First Name: John
Last Name: Gulbankian
Location: Massachusetts
Contact:

Re: New triple gear pins?

Post by J and M Machine » Wed Sep 23, 2020 8:21 am

Just so everyone knows the triple gear pins are pressed out towards the magnets as the pressed portion is a different size in flywheel.
I would be aware of the hardness of the triple gear pins as we just did a flywheel assembly and the pins weren't hardened properly.
What I mean by this is when i received pins I noticed there were scratches on them. Typically the pins are hard but i took a file and went across the end and I was able to remove some metal. Meaning the pins are soft and will wear out prematurely.
As Mr.Jelf mentioned about wobbling I would also be aware that some flywheels that pins had pins replaced may be cracked.!
There is one triple pin hole that lines up with magnet and dowel hole of flywheel and they always crack there.

Just a word to the wise to be aware of quality of parts being made.

We set the triple gear bushing fit to .003"


Dan Hatch
Posts: 4111
Joined: Tue Jan 08, 2019 7:31 pm
First Name: Dan
Last Name: Hatch
Location: Alabama
MTFCA Number: 49974

Re: New triple gear pins?

Post by Dan Hatch » Wed Sep 23, 2020 9:12 am

Look into ballizing or ball burnishing. This is for the bushings.


Dan McEachern
Posts: 1180
Joined: Sun Jan 06, 2019 11:08 am
First Name: DAN
Last Name: MCEACHERN
* REQUIRED* Type and Year of Model Ts owned: too many. '14 touring, 2 depot hacks, 2 speedsters
Location: ALAMEDA,CA,USA

Re: New triple gear pins?

Post by Dan McEachern » Wed Sep 23, 2020 1:14 pm

Just an FYI to all. I'm going to start production of the triple gear pins in the next few months. We have the steel on order for the 1st batch now. The pins will be made from a chrome-nickel alloy steel, properly heat treated and ground to size. This project is an outgrowth of making the special pins that are used with my needle bearing triple gear conversion. I've had multiple requests from experienced shops and individuals for a higher quality part, so I plan to make the 1st batch and see what the demand is. These will be available in various press fit diameters to accommodate different flywheel sizes. Thanks all.

User avatar

Henry K. Lee
Posts: 5339
Joined: Sun Jan 06, 2019 11:09 am
First Name: Henry
Last Name: Lee
* REQUIRED* Type and Year of Model Ts owned: Many
Location: South Pittsburg, TN
MTFCA Number: 479
MTFCA Life Member: YES

Re: New triple gear pins?

Post by Henry K. Lee » Wed Sep 23, 2020 5:51 pm

I received some sets from Dan and can say.., “WOW” very nice and quiet! Super work Dan!

Thanks,

Hank

User avatar

AdminJeff
Posts: 988
Joined: Wed Jan 16, 2019 6:32 pm
First Name: Jeff
Last Name: Stevenson
* REQUIRED* Type and Year of Model Ts owned: 1921 Touring
Location: Wilder Idaho
MTFCA Number: 50006
Board Member Since: 2017

Re: New triple gear pins?

Post by AdminJeff » Wed Sep 23, 2020 9:50 pm

I can say the triple gear pin bearing upgrade from Dan is rock solid and worth a look. Just a really, really happy customer. The pic on the bottom is what it prevents, especially when you climb as many massive hills as I do.

Jeff
Attachments
C3E96A61-D080-43BB-87C7-1C7DEB2B9B84.jpeg
99BFFEC1-1535-431B-B07B-98EFD03728D9.jpeg
Assistant WebSite Admin
1921 Model T Touring, 1930 Model A Roadster
Voltage Regulators, Starter & Generator Repair
www.modeltregulators.com
www.modeltstarters.com


CarreyDM
Posts: 11
Joined: Thu Sep 17, 2020 3:46 am
First Name: Gerry
Last Name: Hillstrand
Location: Hinesville, GA

Re: New triple gear pins?

Post by CarreyDM » Wed Sep 23, 2020 10:53 pm

Jeepbone1 wrote:
Tue Sep 22, 2020 12:49 pm
Give Bob a call over at Bob’s antique auto. He’s the one making the new pins. I just installed a set in my trucks flywheel. Nice machining and they installed very well. The end of the pin is slightly oversized to make up for the wear of driving the old pins out.

Brad
Sounds like they know their stuff to make the best fitment!

Post Reply Previous topicNext topic