Magnetic north

[mynthdd2]

Lets return to planning our map reading skills for when hill Tim comes around again...


https://www.bbc.co.uk/news/av/science-environment-52553900/the-north-magnetic-pole-s-great-wander

[mynthdd2]

"Hill Tim"!!!!!!!!????? what is that a computer should change what I am trying to say!!!??? that would be Hill Time actually

[CharlesT]

"Hill Tim"!!!!!!!!????? what is that a computer should change what I am trying to say!!!??? that would be Hill Time actually

And I thought you were referring to HMHT aka Tim. (never can get Monty Python and the Holy Grail out of my mind whenever I see or hear that name )

[Coop]

Hehe takes me back, used to be a thing for instructors to deduct you the odd point or 2 if you never took into account the variation when taking /plotting a bearing

[mynthdd2]

bear in mind how much off course a half degree might take you !! (as it did me on my ML training.... )

[Tringa]

The adjusting for the difference between grid and mag used to be standard procedure but now in some parts of the UK the difference is so small it can be ignored.

Perhaps now the procedure will be find the magnetic variation before you set out and decide if it is worth bothering with.

Dave

[ChrisButch]

The adjusting for the difference between grid and mag used to be standard procedure but now in some parts of the UK the difference is so small it can be ignored.

Perhaps now the procedure will be find the magnetic variation before you set out and decide if it is worth bothering with.

Dave

A couple of months ago I did some very careful tests on this from the back of my house with precisely identifiable skyline high points. Try as I might, I could find zero distinction between grid and mag.
There are now websites (eg https://www.magnetic-declination.com/) which give you instantly the declination for any location, but of course this is declination from true not from grid. The OS is rather anachronistic in that its maps don't show the relationship between the OS grid and the UTM grid, whereas all other countries' topographical maps which I'm aware of show the UTM grid numbers as a matter of course.

[Caberfeidh]

"Hill Tim"!!!!!!!!????? what is that a computer should change what I am trying to say!!!??? that would be Hill Time actually

And I thought you were referring to HMHT aka Tim. (never can get Monty Python and the Holy Grail out of my mind whenever I see or hear that name )

Indeed. I can rarely go a day in the hills without a Monty Python quote. Did you all know that the Coe starred as the Gorge of Eternal Peril in Monty Python and the Holy Grail? When the knights fail to answer the old man's questions three and are cast into the Gorge of Eternal Peril, it was Hamish MacInness throwing dummies into the air and down into the gorge of the Coe. Passing motorists on the A82 must have been puzzled to see the leader of the Glen Coe Mountain Rescue Team apparently being a bit slap-dash in his handling of casualties...

[jmarkb]

bear in mind how much off course a half degree might take you !! (as it did me on my ML training.... )

Must have been unusual circumstances? A half degree error puts you about 9 metres out per kilometre walked. The errors involved in actually following it on the ground are likely to be much bigger - https://originaloutdoors.co.uk/blog/which-is-more-accurate-mils-or-degrees/ suggest that the "accuracy of a human-plotted bearing using a handheld orienteering compass is 1-2 Degrees AT BEST."

[gaffr]

Hello... A wee tweek seems to do the job.
When I first began using Silva compasses in school the tweek was much more significant....around 12 degrees if I recall correctly.