When Were Lock Washers Introduced to Model Ts ?

[George House]

The other day I was disassembling a 11 7 19 Model T motor when I recognized the block/crankcase bolts were cotter pinned but the trans cover/crankcase bolts/nuts were fastened with lock washers. This made sense I thought because the engineers determined the hogsheads had to be removed on occasion to change bands. This begs the question: were the cotter pin/lock washers used in this way for this reason from the beginning or were the lock washers introduced at a later date perhaps at band changes ??

[DanTreace]

From the Encyclopedia:

1924:
FEB 2, Acc. 94, (“Bolts, Nuts, etc.” folder) Letter from W.C. Klann to Martin and Howard:
nd
“On Dec. 2 , 1924 Mr. Martin and Mr. Galamb O.K.’d
building motors with no cotter keys in the bolts but using lock washers instead in the crankcase, transmission cover and cylinder block assembly only. Why not put this on the blue print? Please advise.”

[George House]

That’s perfect Dan ..Thanks !!

[Mark Gregush]

Several other places used the lock washers earlier; under the screws that held the starter on and the pinion housing bolts when the open type was introduced about 1920. The starter and generator had a number of them too; brushes, screws for the brush plate etc.

[George House]

Yes. I knew that Mark. My question concerned the bolts through the crankcase that Dan precisely answered.

[Mark Gregush]

And I was adding to what Dan said for others reading this.

[DanTreace]

Thanks Mark

Maybe others will do a full list of lockwashers on the T! like the list done by Murray Fahnestock's "Lizzie's Hairpins" where he listed the cotter pins!

To add more: lockwashers under the 4 Bendix cover screws.

[John kuehn]

After dissembling several T engines over the years and noticing lock washers being used in different year motors I have a feeling that back in the T era they were used more often as time went on in repair shops. For a purist using the original style is probably a must but in everyday use in a repair shop from the 20’s and onward I bet the mechanics really got to like using lock washers when putting the engines together.

[J1MGOLDEN]

Some of the blocks that I have disassembled have a groove cut for the smaller or thinner lock washers and also cotter pins.

I have only found those thinner lock washers on house and garage electrical fittings in fuse boxes.

[Fordwright]

https://www.boltscience.com/pages/helic ... ashers.htm

Helical spring lock washers have been in use for well over 100 years. They are still used on many applications in the belief that they will will "lock" the nut/bolt to the joint and prevent loosening. The body of evidence, based upon both experience and experimental results, is that they do not prevent loosening and can be shown to actually speed up the rate of loosening in many cases. Junker originally showed in his work published in 1969 that these washers are ineffective in preventing loosening. Joints containing these washers have come loose resulting in structural failure leading to both material and human loss.
A series of tests were performed by Bolt Science to illustrate the performance of this type of washer compared to a plain nut by itself. The results are shown in the videos and in the preload decay curve below. The preload decay curve is from the tests shown in the video. The tests were performed on M8 fasteners.

[John kuehn]

This is an interesting post.
Did a google search about lock washers. it shows that lock washers were patented around 1922.
Ford started using them in 1924 so that would seem to show that Ford was starting to use newer technology in fasteners. A little here and a little there as time went on not only in nuts and bolts but in other ways to try to improve his Model T.

[DanTreace]

John

That patent in 1922 may only have been an improvement on existing art of past mechanical locking means.

But as the earlier post, lock washers have been around for over a 100 years, found one ref in 1904, this offering in Motor 1906 shows pretty much today's lock washers. Ford used them in many places early on.