Tools & Fabrication - Making bolt hole larger?

I'm making brackets to attach my factory seat brackets to a set Lancer Evo Recaro seats. I'm using a 3" wide, 1/8" thick steel strip. My measurements were slightly off, and the bolt holes I drilled are just a little misaligned. I want to elongate the holes a little bit, but it's a huge PITA. I used the sanding bands on my Dremel to do a couple of the bolt holes, but I used up every one I had. I also tried using a tapered grinding bit they had, but it didn't do much. Also, getting the bolt holes elongated enough by sanding took a lot of time. Anyone know a faster, easier way to do this?

Yeah, ditch the dremel and get something with some balls. And try a carbide bit next time.

use a round file (Rat Tail File)

A UNIBIT from HD or Lowes is what we use. Makes a round hole in thin material, and will enlarge the holes in steps..

http://www.google.com/products/catalog?q=Unibit&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&cid=17440243887304188030&ei=1HGsTMawBoG78gb7gM2vCA&sa=X&oi=product_catalog_result&ct=result&resnum=2&ved=0CCMQ8wIwAQ#

x2 for the rat tail file, the unibit would be good too if you can put washers on top , as it will only make the mis-aligned holes bigger.

You can get a "good enough" 1/4" electric die grinder
off eBay for about $15. Carbide tulip burr, under $5
(you may find them at Ace too). Ain't nothing gonna
stop that from hogging. Other than another chunk of
carbide, or you gum it up with aluminum.

x3 rat tail file.

Die grinder and a good carbide burr bit. Done in 5 minutes.

Hand file for enlarging holes in steel? No. :bang:

i would use a die grinder with a carbide burr , quick and precise

Hand file for enlarging holes in steel? No. :bang:

Are you kidding? On a piece 1/8" thick, it wouldn't take more than a few seconds per hole.