Blocked

I can’t decide whether to block my sweater pieces. I’m done with the front and the back, and have been toying with the idea of sewing those together before starting the sleeves, mostly to double-check that it will fit. But seeing as it’s chenille yarn, I’m not sure how to go about blocking it. Will it flatten? It’s acrylic – will the iron melt it? I suppose I should test it on my swatch first, but that woud require patience…of which I’m in short supply lately. Any knitters out there have any ideas?