The back rake is 60 inches and made with r+r spikes and the gap between them is about one inch. I got the idea when someone on here was talking about using spikes for a tooth bar. I bought about $40 of new metal (20foot of 1/2 by 1 1/2 bar) the rest is all scrap metal I buy for 25 cents a pound. I'm not sure how much it cost to build but I do know it was under $200. It will be more if I ad wheels to it.