A rather lengthy reply to Jennifer's message

Thanks Jennifer for leaving a comment - much appreciated.  It is always nice to get some feed back from folk to see if I am being any help to anyone.

I did put a note somewhere about using eye protectors and a mask - maybe not on the video you saw - I must go back and have a look and add it to all of them.  So thank you for prompting me to do to that.  You are right - I hate MDF dust - irrespective of  health issues - it makes me itch and drives my eyes nuts so drilling and sawing is really truly best avoided as much as you can.  Indeed I have actually gone back to cutting two lines with a knife and gouging out in between as I am not a dab hand with the Dremel and really can't be bothered mastering it.

Don't let that put anyone else off - some folk love them and get loads of good use from them.  Horses for courses in this game.  Like any other hobby you find what fits you.

It is difficult with a blog and videos spread out over different time scales to recall what is written or said where so, yes, I did mention a lino cutter somewhere in passing but it is good to remind people that this is a very good alternative.  The only reason it didn't work for me was that I was a cheapskate and bought a second-hand blunt one!  

So, in summary - cutting grooves - 

• Rotary tool if you like them and are a confident using them and remember to wear safety glasses to protect eyes from flying broken tools (it can happen) and a dust mask over nose and mouth to protect you from dust.
• Lino cutter - good size - brand new and sharp
• Box cutter (strong knife) score two lines and gouge out in between
• V-shaped chisel - again new and sharp

Any other ways of doing it please share here....

Thanks again Jennifer, nice to meet you.