New branches-pinch or not?

[Vjeno]

Hi everyone…

In early spring, I guy-wired this overgrown maple to let the sun in and promote some new branches to pop out. Now, after a few months, here they are.
This is Atropurpureum with pretty big leaves and long internodes, not the best variety for bonsai, I know, but now I’m thinking: is it a good option to pinch new branches to keep them in control, or is this going to be stressful and I will risk losing them?

 

[Paradox]

There isn't enough to pinch yet.
The idea is for these to grow into branches.
Let them extend out a bit before you start pinching new growth

 

[Vjeno]

There isn't enough to pinch yet.
The idea is for these to grow into branches.
Let them extend out a bit before you start pinching new growth

Yes…right now they are too short, but generaly…do I need to wait some longer period like next year or I can try to control elongation by early pinching..

 

[Paradox]

Yes…right now they are too short, but generaly…do I need to wait some longer period like next year or I can try to control elongation by early pinching..

Yes but you need to think about how long you want the future branch to be and allow the branch to extend part of the way, keeping in mind the further ramification you'll want to build beyond that.

 

[Shibui]

Lower branches are generally suppressed by stronger upper growth so those new shoots low down will only grow very slow and will occasionally even die if the upper branches are allowed to grow strong. I would be concentrating trimming around the top while these new shoots are developing.
Japanese maples will grow from dormant buds so allowing free growth of new branches is not a problem. Strong growth will help thicken new shoots to the stage they actually look like branches so allowing growth is desirable at this stage. At this stage I just set initial branch angles before the stem hardens and becomes difficult to move. Beware that very new shoots are very weakly attached to the trunk and rough bending can snap new shoots completely out of the trunk.
You are already aware that Bloodgood naturally has long internodes so it's difficult to reduce but if internodes are excessive I trim new shoots back to lowest usable nodes and start again at each trimming. May seem to be a backwards step but pays off in the long run.