Man, that was a bugger. And I consider myself a pretty good filer.
Does your axe already have an existing waffle poll that you want to renew or are you starting with a smooth poll? If starting with a smooth poll I think a fellow could lay out a 1/8" grid with a fine point Sharpie pen and thin metal ruler.
Begin each new line at the edge of the poll. Use a file with the sharpest corner you can find. I have some knife files (knife-shaped blade) that I thought would be best but they weren't. I had the best luck with either a cant file (not 'safed') or small half-round file - both smooth cut (fine teeth) files.
I'd say you're going to want to visit a machinist supply store and pick out some files before even attempting this. You'll also want a smooth cut triangle file - I made do with an 8" but a 10" or 12" would be better. And of course you'll need a file card, a vise and some wedges.
Once you get the cut started on the corner of the poll slowly advance it down across the face until you establish your line. If at first your cut is slightly off line you can correct it by applying pressure to the opposite side of the cut during the next few strokes and get your file back on the line. I did this a lot. Check your alignment frequently.
Use the sharp cornered file until you have the line established all across the face of the axe. Then switch to the triangle file. The triangle file produces the proper angle for a checkered poll.
Again, while working the triangle file continually check that your lines are straight, parallel and evenly spaced. When you start to get off (and you will) put force to the opposite side of the cut until you're re-centered.
Patience and commitment are required. It's a lot of work.
