need to cut a carbon steerer, I have the proper "guide", what should I use as the cutting tool?

Laser.

Mask it in tape and then use a fine toothd blade

http://cyclinginfo.co.uk/products/uncategorized/cutting-carbon-fibre-equipment/

I used a fine mini-hacksaw on carbon bars with some oil and put inside a larger metal tube to cut it straight – I was careful not to push hard and sawed slowly – seemed to work a treat!

big_n_daft's garage floor, later tonight.

thers's something on the easton website about this. You need a 32tpi or higher hacksaw blade (decent hardware store should be able to sort you out for this – I got one off a market stall in Chesterield). Dont's use a pipe cutter. Masking tape is good.

measure twice, cut once…..