Slip-Tongue Spline Question

[JIMMIEM]

I'm installing 3/4" solid t&g flooring. I've made up some spline stock for the backlaying work. I've read some info that recommends putting a piece of floor board, with its groove enveloping the spline, beside the flooring nailer to keep the spline at the correct angle as the double-splined board is being nailed. If I use this technique to keep the spline aligned is it necessary to glue the spline to the double-splined board? I'm sure that adding the glue wouldn't hurt but does it really help in this situation? I can understand gluing the spline into one of the boards in an end-to-end joint where there won't be a nail.

 

[FloorMaven]

...If I use this technique to keep the spline aligned is it necessary to glue the spline to the double-splined board? I'm sure that adding the glue wouldn't hurt but does it really help in this situation?...

If you look at it a nail would barely hold it in place.

 

[hardsurfaceguy]

A spline must be glued into only one side so they can expand and contract independent of each other

 

[JIMMIEM]

I glued the spline into one groove as you folks have recommended. I used some cutoffs to keep the spline properly aligned while I nailed it. The next board fit to the glue/splined board perfectly.
Thank You