Drill a hole in a chain saw bar

[RenaisSAWnceMan]

When I needed to make two new adjuster-pin holes in a modern Stihl bar, to make it workable on the 090AV, I found that, once I moved up a few bit-size-steps beyond the pilot....even cobalt bits just kept rounding. Ultimately, having opened up to a hole size that would so-permit, I used the small cylindrical Dremel grinding stone to open the holes up to-requirement, and it worked rather quickly and easily.

Stuff was just plain hard......

 

[Seminoles_1]

Depends on the bar as some bars are harder than others.

Use a drill press with low speed and high force. If it's soft steel like Oregon bars, you should be OK with a sharp HSS or cobalt bit.

If it's hard steel like the German Carltons, or if you need to drill through the sprocket bearing, which is harder than the bar, then a carbide bit or a centercutting carbide endmill is recommended.

First time on here, tried askin Google but sent me here, drilled holes in my 20 inch chainsaw bar, to rig up a homemade saw mill, had it all done ready to saw and believe it would have worked, my question is is it safe to drill multiple holes? I was about an inch off on both sides, so need to drill to more holes?