What size clamps?

[BrotherInKrime]

I am ready to place an order with McMaster for beer and gas line but I don't know what size oetiker clamps to purchase. I ordered this (5181K42) beer line to go with a 1/4 in barb and this (5181K35) gas line to go on a 5/16 barb. I don't know how to calculate the outer diameter of the line over the barb to figure out what size clamps to get. I have searched these forums for an hour with no luck in answering my question. If someone has a link to a thread with an answer, can tell me how to figure it out, or has part numbers I would be extremely greatful. Thanks.

 

[ehedge20]

The outside diameter of the tube is listen in the part description in which you can order your clamps from that. Some of these clamps have notches for adjust-ability so just order something that is 3/16" - 1/4" bigger than the Outside Diameter and you should be okay. Or you could just order a different kind of adjustable clamp as they will all work. In fact if you go to MC Master they have drop down lists to help you figure out what you need: http://www.mcmaster.com/#hose-and-tube-clamps/=d9dfc8

 

[mmonacel]

For oetiker clamps you want to use the gap-free pinch clamps with tongue and groove from McMaster.

To figure out what size you need, you will need to determine the outside diameter of the tubing. It's easiest to do this in millimeters since when looking at the clamp range on McMaster it's easy to match it up rather than looking at fractions. Keep in mind - when you order gas / beer line from a homebrew shop, it's typically sold by the inner diameter (ID) not the outer diameter (OD). So if you ordered 3/16" beer line, 3/16 is the ID of the line, not the OD. You'll want to measure yours, but below is the typical ODs for beer and gas lines.

Beer line (3/16 ID; 7/16 OD) - McMaster part 52545k51
Gas line (5/16 ID; 9/16 OD) - McMaster part 52545K54

If you want to do an easy measurement and conversion just use Google. Enter in: 9/16 in in mm (yes that's two in's...). This will give you the millimeter equivilent to match up in the chart. If more than one clamp meets your needs, choose the one that is in the middle of the clamping range as opposed to the top or bottom of the range.