rail overlap and concave bottom depth

After my shaped blank comes back from the glasser, I find my v to be shallower and my concave to be deeper. I realize that it’s due to the extra thickness from the rail overlap. So, do I sand the rails more ( I’m afraid I’ll go too far into the cloth) or do I compensate in advance by making the v deeper and the concave shallower ? What’s the usual approach industry wide ? OR is it that the glasser is not taking the bottom overlap down enough before hot -coating the bottom ?

all those options will work…you can sand to adjust…or you can ride it as is.

theoretically a lap should not change much (6oz glass is only .009" thick, 4oz is .005")

…it depends a lot on glassing technique

and like you said, proper planning…your situation is not unusual…

Hey patrickfreen,

we’ve been “shaping to the glass job” for years esp. on corner build-ups. You’ll find that shaping compensations will vary depending upon which glass factory you use; if your really into it…


I the board feels jusr right, brfore glassing then it is to big. Glassing adds a lot more volume to the boad than you realize.


plus one- thanks for the info - makes sense.

You can expect this to always happen. If you use the same glasser/glassing schedule you can learn what to expect and compensate in the shaping.