Chambers kit question

[Rt5403]

So I'm building the Chambers .12ga New England Fowler kit. They sent me a list of tools in an email. It calls for a 60° countersink. I was looking through some other topics on their kits on here and see people using 82° and 90°. Anyone built one of these know which one I should get?

[bluenoser]

Countersinks are available in a range of angles - the angle being the included angle of the countersunk hole.  I have 60, 82, 90, 100, 110 and, as I recall, 120 degree countersinks.  If the included angle of the screw head in the Chambers kit is 60 degrees and you countersink the hole with an 82 or 90 degree countersink, the screw head will make contact at the bottom of the countersunk hole, but will leave a bit of a gap at the top.  Conversely, if the screw head has an 82 or 90 degree include angle and you countersink the hole with a 60 degree countersink,  the screw head will only make contact at the top.  Better looking situation, but still not good.  I would say get a 60 degree countersink if that is what Chambers calls for.  When it comes to countersinks for installing the touch hole liner, the contact area is so narrow that if an 82 degree countersink was all you had, and it should have been 60 degree, you should be able to lightly peen the liner to fill the gap.  But why would you do that if you have to buy the countersink anyway?
Perhaps Jim will chime in.

[Rt5403]

Thank you for the insight. I wonder if the screws and the vent liner all take the same angle?

[flehto]

I've built 2 Chambers' early Laancaster parts sets and only used an 82 degree ctsk......Fred

[Mike Brooks]

I have used the same countersink for over 40 years. I have no idea how many degrees it is.

[Frozen Run]

Since Chambers recommended the 60 degree and the 82 degree is so common for everything else, it couldn't hurt to get both. They're very useful to have around the shop. I like the Weldon 0 flute, made in the USA, very fast and clean cutting with no chatter. Practice on some scrap metal before committing to your gun. 

[Hatchet-Jack]

I use an 82 degree countersink for screws.

[Bob Gerard]

My countersink is usually room temperature. 

[Birddog6]

So I'm building the Chambers .12ga New England Fowler kit. They sent me a list of tools in an email. It calls for a 60° countersink. I was looking through some other topics on their kits on here and see people using 82° and 90°. Anyone built one of these know which one I should get?

If Jim Chambers sent you a Kit, and list of tools, & on that list it says use a 60 deg countersink, I suggest you get a 60 deg. countersink. He might know what he is doing.   

[Mike Brooks]

My countersink is usually room temperature. 

Mine is hotter during the summer and colder in the winter. Odd.....