Thank you for your easy to understand explanation. At last, somehow to link previous posts to this one.
It must be a 'kid' thing, Trevor said what to do in youngie speak, woosh right over the head, so I have been waiting to catch him between work, running, etc to tell me how to do it.
Your son came up with this idea, again a but of youngie, and I was scratching my head when I opened up his link to your explanation.
By Jove. I think I've got it, will have a go tonight.
You now have another follower, thanks.