HELP with scal and Inkscape to get to cut single lines

Nine times out of 11 when getting a single line to cut
using scal it will end with a extra line cut from it
at an angle that is not needed .
(learned this lots from trial and error with the lattice cards
and pop up cards )
The only way i have found around it (there could be others)
LETS BEGIN

In inkscape if i just drew a line like this
it would cut like the above

so what i do is draw a line
(ok first i am leaving the red line there and starting again with a blue one to show the difference)

NOW you highlight the line and do a "control d" on your keyboard
(which will duplicate one on top of that one)

Don't move the duplicate copy leave it on top
Highlight them both by using the top ;eft hand side arrow key and
draw the box around the two on top of each other
(you will notice down bottom of screen it will say
"2 objects of path......."

Now path and combine

Now edit path by nodes ( 2 from top left hand side)

Highlight the top two nodes that are on top of each other

Click the join selected endnodes (third in on top line)

highlight bottom two nodes that are on top of each other

Click the join selected endnodes (third in on top line)

Now they cut with out the end slit in the wrong direction
NOTE this is not just for straight lines it is for anything that
you want to cut that stops at an end
(like an O that finishes but a curve stops so it has a end and at that end
the cricut will want to finish it and will go in a different direction )