making Head buttons

[dwilfong]

I thought I would pass this on for those that make there own buttons.

I have started using radius end mills and found theses on line.

The 3/8 end mill will make a very nice .21 chamber.

their are different radius on the mills and you can make some nice chambers like what the MAC .21 had.

Just dive in no measuring or making special tools.

Will give you a flat side radius corner chamber.

https://www.lakeshorecarbide.com/cornerradiusendmills-2-1.aspx

 

[Rick Sowell]

David, which of these mills have you used and for what engines? I have never seen different radius mills before. Thanks

 

[dwilfong]

Hear are some test cuts for a .45 head button chamber that I made with the .120 radius .500 end mill.

this is .140 deep making a .40cc chamber.

this one is .120 deep making a .33cc chamber.

I like this as the flat that is left on the chamber floor is .250

This is the same as the plug size.

The radius starts at the plug and stops at the entrance to the cylinder at the .120 depth.

At .140 deep it leaves a .020 flat on the entrance to the cylinder.

In my 45RS this will leave a nice .177 band for the squash.

I think this will work well on any .45 eng.

 

[lundahl]

Looks good.

 

[Albert Araujo]

What is the best material to use and why????

Albert

 

[dwilfong]

Albert all my buttons are made of 306 brass. I like this because thy hold up better to detonation. Also I feel that the brass maintains the chamber heat better.

Keeping the chamber hot is necessary for burning nitro. how many restrict the water to get the eng hotter?

A hot head is a happy eng.