Stair riser templating when treads are already in

Question

I've made a huge mistake.

Got new treads / risers / skirt boards.

The treads don't have a groove for the riser, it's a flush tread all around.

Installed the risers (nailed in) then the treads (glued down).

I used a stair template tool to get the precise cut for the risers and the tread since the wall is not true.

Wife didn't like the white risers, so we decided to replace them.

However, the idiot that I am, built a shelf out the old risers and now can't place my template because the tread is in the way.

I could get a template by using a compass tool (if I cut the 6" arm down) but I worry that I won't get the bottom stair tread distance accurate enough because there's no great way to get a tape measure in there and get a precise reading.

I don't trust the accuracy of the laser measure either.

Any suggestions ?

I also realized I might have issues inserting the riser so I figured I would table saw the top of it at 45 degrees since it will be covered up by trim anyways.

Answer 1

1) Make your own template with t-nuts and the knobbed bolts of your bought template

or

2) Use your templates just in front of the bull nose (shouldn't be a significant difference between there and the final riser location), using s scrap of 1x or what ever to keep the template parallel with the plywood riser. Find the largest riser, cut it first knowing that if the template location causes it to be unsuitable, you can use it on step requiring a smaller riser.

Answer 2

If you must template, do what the countertop guys do: 3" strips of luan (or something like 1/4" ply), hot glued together in the corners with a couple of staples for good measure.