First year trying to graft and my question is, once it seems to have taken, when is it safe to bring out to full sun???
I grafted this little guy on 3/4/16, seems to be happy so far. It has been outdoors and in the shade for about a month now, took it out once it started to break out.

 

Great question. I've been gun shy about bringing my grafts outdoors too. They've all been sitting on the window sill. What did you graft together?

Start by bringing them out into the sun a few hours a day. Gradually work your way up. Maybe 1 hour for a few days, then 2, then 3, after a week or so they should be well enough acclimated. 

I put a big black madeira graft out for 3 hours the other day and it got sunburnt lol. Definitely start slow :)

@Ben, it's an LSU Purple I received from JoAnn in a trade, THANKS JOANN!!! I grafted it to an unknown green/red I rooted last year. I'm at about 25% success rate on grafts but it's still too early to tell. This LSU and one other VdB have taken fast and have good signs of growth.
I've lost a few cuttings in the past due to bringing them out too soon and not being able to handle the sun, don't wanna do the same with these grafts.

Hi,
My take on that is that you want to shade the graft union - not the leaves of the pushing bud.
The sun could cook the new growing tissue at the union graft.

You can use tin-foil or saran wrap.
I myself used saran wrap that I scotched on top of the cutting/branch and let it down to cover below the graft union.
My idea is: I water the saran wrap to keep some more moisture against the graft.
I'm monitoring the bud break and will make a hole through the saran wrap to let the bud and new stem escape. In 3 or 4 months, I'll completely remove the scotch .
I tried some grafts on a cherry seedling.

JDS... I lost a graft because of the moisture that got trapped with the grafting wrap I used, it was a wedge graft where the root stock I used was a little wider than the scion and the extra space seemed to work against it. Not sure if I had anything to do with that when watering though...
For now I'l just keep it where it is till I feel it's a bit stronger, maybe a couple months then bring it out slowly...