Flat vs Beveled Washer

Help Support Plumbing Forums:

JIMMIEM

Well-Known Member
Joined
Aug 9, 2014
Messages
142
Reaction score
10
Location
,
I removed my outdoor faucet and took it to the hardware store to get a new washer. They had a large variety of sizes but none was an exact fit. I got one that was a bit smaller as the employee said that the sealing doesn't take place at the outer edge. I also took a bevel washer of the same size. The original washer was flat. Is it ok to replace with a beveled washer? I'm thinking that the flat washer will widen when it is compressed. I installed the flat washer and it works. I'm just curious about washer sizes....the hardware store had dimensions in 32nds?
 

SHR

Member
Professional
Joined
Mar 5, 2014
Messages
643
Reaction score
294
Location
, Minnesota
The flat washer was the correct choice for your faucet. Never measure the old washer when shopping for a replacement. The old washer will have bulged out to a larger size from constantly being compressed when the faucet was shut off. Always bring the stem so salesperson can measure the cup where washer has to seat in to in order to get the correct replacement size.
 

Mr_David

Easily Amused
Professional
Joined
Jan 11, 2010
Messages
4,170
Reaction score
1,058
Location
Santee,Ca,
Bevel will work but it may reduce the flow if the stem cannot move away from the seat far enough. Being that it is a little thicker.
And you will need a longer screw.
 

MC NC

New Member
Joined
Nov 8, 2019
Messages
1
Reaction score
0
Location
USA
Similar question, I took the stem into the hardware store. Could find the exact fit. 3/8” was a little small and the 1/2” wouldn’t fit. Some of the sizes had an L and an M. What does those stand for? I used a 3/8L and the faucet still drips. I am thinking I need to find 1/2” with a letter next to it that is not an L. That was all the store had and it didn’t fit the stem.
 
Last edited:

Diehard

Well-Known Member
Joined
Aug 19, 2017
Messages
2,640
Reaction score
469
Location
North Reading, Mass.
(000) ≈ 1/2" = 15/32"

1/4S (00) ≈ 1/2" = 16/32"

1/4M (0) ≈ 1/2" = 17/32"

1/4R = 9/16" = 18/32"

1/4L = 19/32"

3/8R = 5/8" = 20/32"

3/8M = 21/32"

3/8L = 11/16" = 22/32

1/2R = 3/4" = 24/32

1/2L = 25/32

5/8R = 13/16" = 26/32

5/8L = 15/16 = 30/32

3/4R = 7/8" = 28/32

Then comes the question of whether you should buy beveled or flat washers? Apparently the beveled washers are of European origin while the flat washers are of North American origin, with both intended to do the same job. It seems that originally the European seats were a bit funnel shaped, so that the slope of the beveled washers would contact a larger surface. They both appear to work in any fixture that requires washers. For all practical purposes I will accept the comment made by Ed, one of our viewers who didn't say in the e-mail where he was from: I have known for many a year (I'm now 81) that if you want the water to come gushing out fast as soon as you open the tap, then you use a flat washer. If you want the water to flow slowly at first and gain speed and volume as you open the tap more and more, then you install a beveled washer."
 
Top