Than I think the problem is with the injector.After I inject the mold,I inject the leftover plastic back into the remaining hot plastic.When I open the injector,there`s about 1'' of plastic still in it. Its a used injector,not sure what brand,but I just bought a new 1 from BT,and a blending block. Next time I`ll see if the new one has plastic in it after pushing the push rod all the way down to empty it. As for the sm. blending block from BT,its works great. I`ve used the 2 injectors and the block and made some great baits.A perfect 50/50 color when I push the handles down together. Started with some leftovers,and quickly got the hang of it. The drawback is the injectors need to be side by side and touching each other to put them in the sm. block.If anyone is considering getting a block,get the larger one. fsh4fun