I need to drill a 1" diameter hole in solid brass

[scmhogg]

I'm making a couple of carving hammers with round brass heads. To attach the handle, I need to drill a hole 1" in diameter and 1 1/2" deep in solid brass.

I don't have a twist drill that large, and they seem very expensive. I originally planned to use a Forstner bit, but, everything I could read, only mentions use in wood.

Can I use a Forstner? Spade? Or, one of those round top bits you can use on glass?

Am I stuck having to buy the 1" twist drill bit? Only three holes necessary. Any suggestions on a cheap way out.

Steve

[Whaler]

I would think that a carbide tipped Forstner bit at a slow speed would work.

[cabinetman]

Brass is relatively soft to drill compared to other metals. I would suggest using a bi-metal hole saw with an adjustable center pilot drill. Have a minimum pilot depth to the outside cutting edge. Mark or set the depth on the DP and drill slow with a cutting lubricant. Once you have reached the depth, you can hog out the inner waste.

It can also be done with a carbide tipped forstner bit, on slow speed in the DP, and using a cutting oil. You'll have to allow for periodic cleanout of brass cuttings.

Whatever method you use, make sure you have the subject material well braced.
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[pelligrini]

Good timing with your question. I also need to drill three 1" holes for a missing plate for one of my Wiltons. It won't be as deep, probably in alum too (already have that) maybe 1/8" steel.

[charliex]

Find a 1/2" steel or brass rod and drill the hole with a 1/2" bit. Put the rod in the freezer and get the brass head hot: Quickly insert rod. When it cools it should be in tight. Drill the handle for the rod and epoxy in. You may have to pin the head to the rod if it don't fit tight enough. OR you could thread the rod and tap the hole. (my choice) I have a small brass peen hammer that I made over 20 years ago with this method.

If you are turning the handle you could make the tenon the same size as your largest bit and pin, epoxy or CA the head on.
Good luck with whatever you try.
Chas

[scmhogg]

Thanks for all your ideas.

I have a couple of extra 1" HSS forstners, that I can sharpen up. If I go slow with cutting fluid at the slowest speed, what's the worst that can happen?

I'm impatient, I don't want to wait for a 1" carbide to be delivered.

Steve

[cabinetman]

Thanks for all your ideas.

I have a couple of extra 1" HSS forstners, that I can sharpen up. If I go slow with cutting fluid at the slowest speed, what's the worst that can happen?

I'm impatient, I don't want to wait for a 1" carbide to be delivered.

Steve

You'll be able to tell if they dull out. You may have to dress 'em up to finish. Try not to resize them. Maybe wear eye protection just for S&G's.
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[drillman88]

This may sound a littlle weird but with regular twist bits a duller bit sometimes works better on brass. Brass is soft and tends to grab sharp edges the duller edge will cut but not grab.I have never tried a forstner bit on brass so I am not sure if this will apply but if the sharp one grabs a duller one may work .

[thegman]

You might check out this link that has a few tips and feeds and speeds.

http://metalworking.majosoft.com/html/how_to_drill.html

[Len]

In my machinist days I made several brass hammers using the technique CharlieX suggests. They all lasted long enough to get "disappeared" by someone too lazy to make their own.

Use a spiral flute 3/8 or 1/2in end mill to clean out the waste if you go with Cabinetman's suggestion about the hole saw.

Len

[scmhogg]

Update

I glued the brass heads to a piece of plywood with Gorilla Glue. I used a 1" HSS Forstner. I set the drill press speed to 200 RPM. As I was afraid that the brass might grab the bit and break the glue joint, I slightly loosened the belt drive. I wanted it to stall rather than try to spin the blank.

It was slow going. The chips were too heavy to be ejected. I had to stop every few seconds to vacuum the chips out of the hole with my shopvac. I used cutting fluid, though I'm not really sure it was necessary. I had to drill a 1/8" pilot hole, as the center spur had difficulty with the brass.

I was surprised that the drilling generated very little heat. The bit was just a little warm to the touch. Over all it was pretty easy, and it made really nice hole.

Sorry the pics are a little blurred. The shiny brass throws the auto focus off.





Steve

[cabinetman]

Lookin' good Steve. Remember that famous statement..."I just love it when a plan comes together". Good thing that the glue held, could have been a real spinner. I might have gone with a Jorgie clamped down.
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