iandvnt said..
anyone make a clamp? instead of using candle holders bottle etc to weight it down
Yes. Thats what I do. Get a hole saw (drill bit) and cut a hole to the size of the outer part of the valve. Clamp to another piece of wood underneath. I use 2 quickgrip clamps to get even pressure.
the tip is to put some talc/flour onto the top piece of wood so that the glue that is compressed out during clamping doesn't stick to it.
You could probably cut a doughnut the correct size out to avoid the problems of glue seeping out and sticking to the wood but it seems more effort for little reward