# End caps



## wmf138 (Jul 13, 2009)

Hi All

A Friend of mine just built a small boiler for one of his toys haven't seen it yet 

and having limited resources used welsh plugs for the end caps looks good and cost was minimal

Oh welsh plug are what we use in the side of motors in the water jackets there round cup shaped disc normally made from brass there properly call differant things overseas 

hope this helps 

Wayne


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## rleete (Jul 13, 2009)

They're known as freeze plugs in the US.


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## max corrigan (Jul 13, 2009)

They are called core plugs in England dunno about the rest of the UK though
Max,,,,,,,


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## d-m (Jul 14, 2009)

Hi I have been an auto mechanic 35+ years allways called them welsh plugs. That's what my voetec teacher called them and knew everything (well when you are 17 and new it seemed like he did) and I have had more than one heated conversation over the name on these.
Dave


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## vlmarshall (Jul 14, 2009)

I've always called the smaller ones (flat dome shape, covering passages in carburetors and injection pumps, etc.) Welsh plugs, and the larger, cup shaped plugs, freeze plugs.


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## BMyers (Jul 17, 2009)

How would brass frost plugs work in small boilers ?


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## shred (Jul 17, 2009)

FWIW, Brass isn't a great boiler material, even though a lot of the toy and low pressure boilers use it. Zinc can leach out over time rendering the remaining metal weak. Most model boiler codes only want brass for removable/replaceable parts like valves and fittings. 

How thick are the frost plugs?


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## BMyers (Jul 17, 2009)

I am guessing .050 thick or so. I wonder if anyone makes copper frost plugs


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## Stan (Jul 17, 2009)

Before antifreeze was readily available many people drained their engines during cold weather or used a methanol/water mixture and the methanol tended to boil out of the water raising the freeze point. When a car was towed into a garage, the first thing the mechanic did was open the hood and look to see if the frost plugs were pushed out of the block from freezing.

A core plug is a reasonably accurate name as they plug the hole where the sand core was that held the cylinder in place during casting.


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