If you like, but there's no need. As long as you don't batter the tube off with an axe you'll be fine.
The only critical thing is that the cut is a few mm inside the stem. Doesn't have to be square.
I know where you are coming from and I probably could do it..... I could improvise something from stuff I have but I like having the right tool for the job. I don't have a great deal of tools but over the years I have bought the necessary tools to look after my bikes and do most jobs. I bought the Lidl tool box about 3 or 4 years ago and while most tools are ok for what I need, the cone spanners were poor so I took advantage of an offer in one of the online stores and bought 6 Park Tool spanners which make the job a joy to do, £30 well spent in my book. I have serviced probably 10 hubs since then.... I'm sure the LBS would have taken more than £30 for that..... plus, I get as much pleasure out of fixing my bikes as riding them
There's a lot of pleasure to be had when one can improvise a tool or a method and save money in the process. I do that sometimes but this time I just want to buy the right tools. This time the pleasure will come from doing the job right ( I hope
) and from knowing the tools would pay themselves in a matter of weeks.
