Chopping is time consuming when creating a mortise, which is why I prefer to bore with my brace and bit. But isn't it annoying and downright shameful when you can't get the bit dead centred between the marking gauge lines? I will show you how you can every time and it's simple.
There are two ways of doing. Place the business end of the bit between the scribed lines and hope for the best or another method which is my preferred method is to find the centre of your to be mortise with your marking gauge. To do that eyeball the centre, scribe a small line, flip the gauge to the other side and scribe another line. What will be left unless you were lucky is a gap between the two scribed lines. Move the gauge to the centre of between the two lines and test again. Keep doing that till the scribe meets centre from both sides and scribe all the way through.
With a scratch awl prick the centre line with light finger pressure. Do not hammer or press hard because the awl will want to follow the grain of the wood and can throw you off centre. Just a light touch is sufficient.
That's it you're done! BTW this isn't something I invented even though I've never seen it in any book or showed anywhere on the net, I can't take credit for it. Because I'm sure just as boring instead of chopping has been practised for thousands of years, I'm certain someone has had the same frustrations and came up with the same solution several times over throughout the centuries. This is why posting these posts, writing articles for magazines, writing books and making videos are so bloody important to us as a civilisation. Had most of our ancestors bothered to do that we wouldn't be reinventing the wheel again and again and not to mention playing the guessing game of what we think they might have done. I hope this helps and I apologise for taking so long to finish the 5th Issue of HANDWORK. It will get done, it's life getting in the way. If someone has a work around for that please let me know.