I have made mock scrapes before and had a buck in it with 15 minutes of making it. They can work right away. Here is how I do it. I find a small tree within 20 yards of my stand. I make sure it has a shooting lane. I then use a pretty good sized stick or limb and start working the ground. I make sure there are no leaves in it and make sure I really turn up the dirt. Then I will take a tarsal gland or a scent wick (key style) and hang it on a limb above the scrape. I then put dominant buck urine on the tarsal gland or wick. Then I place Tinks 69 in the scrape. I make sure I get rid of the stick or limb I used to make the scrape due to not wanting any of my scent being on it. I then make sure I rehydrate the gland or wick everytime I hunt the stand. I usually make one scrape per stand location...