tooling for boring 1.25" hole?

[warude]

hi guys, i am running a harbor freight x2 machine and am unsure what tooling i can use to bore a 1.25" hole that will work in this machine. thanks in advance for any input, Curtis

 

[DMS]

I have done similar, but it's tough. The think that worked for me was to chain drill to remove the bulk of material. Then I used fly cutter as a kind of primitive boring head to clean things up. I tried a regular 2" boring head, but the setup just wasn't rigid enough. The fly cutter was much shorter and more rigid, and though it was difficult and time consuming, it worked out just fine. I was going through 3/4" steel, and I think my hole was about 2.5". 1.5 should be easier. Make sure you lock your x/y gibs when you do this.

Another option would be a trepaning tool, like this http://www1.mscdirect.com/cgi/NNSRI...re=ItemDetail-_-ResultListing-_-SearchResults, but I never tried one on my x2.

 

[7thMcD]

not familar with your machine but I have been boring similar size holes lately some through 3/8" material and some into 4" soilid round to aprox .700" depth and some bored hole through same material shy of 4" ( had to flip material as cutter max depth is 2" )...an HSS annular cutter works excellent very little torque as compared to a drill bit and made 75 of the .700 depth holes with same cutter ran aprox 250-300 rpm. Always applied some pressure while cutting and used pecking method to limit length of swarf...

 

[warude]

thanks so much for the responses guys, I will be going through aluminum on a few ar15 lowers so not working with anything too hard material wise. I will check these items out. thanks again, Curtis