Additionally take care to work with a sharp knife and try to breath a little bit on the block surface. The humidity of the breath smoothens the surface, the warmth of the breath can render the section thicker.

I recommend you to keep the blocks overnight at 4 degree celsius. Then, immerse your paraffin block in ice water for 4-6 hours before/while cutting sections. Blade should be very sharp and in good angle.

Regards

Immersing paraffin blocks in ice-water is a good thing, but be careful about the duration. Tissue rich of collagen tends to swell (almost out of the block). Mostly a few minutes are sufficient for a better cutting.

It looks as if the tissue was processed too quick. How do you do a tissue processing? it is more soft to use Bouin's fluid instead of the formaline  and then to use isopropil alcohol  with the graded growth of the  concentration from the 50-60 grade to the 70- 80- and, at last,  96 alcohol by volume - it allow not to dry the slide. If you use the automatical procesing there should be 10 steps of the growth of the concentration Then do you use xylol ? If you use isopropil alcohol  you can put the slides just after the processing to the warm paraffine at 35-40C. All together it takes about 24 hours

We have found that rehydrating the muscle by placing the trimmed in sample on a container of ice with a little water on top for a few minutes before cutting is beneficial.

Tissue cut from icy water is almost always homogenous without tears. I have compared tissue cut dry from cold plate with tissue cut from icy water and the best section has always been that cut from icy water . Tell us your discoveries. Take note of time limit to avoid tissue swelling.