Bicycle Mechanics - Cleat screws too short to reach threads

I bought a set of "Look style" pedals made by Shimano. The pedals come with 8mm long 5mm screws. However, I've been screwing with these things for an hour and can only get one screw in. I think I need 10mm screws that fit these cleats in order to reach the threads on the shoes. Where can I get these screws? I checked the LBS, but the store is new and the mechanic did not have these. Also tried Ace hardware...

You need an older LBS. They should have a box, probabaly with a Sidi logo on it, that has several different lengths of cleat screws in it. Your new shop should be able to look thru the Quality catalog(That they better have) and find screws from LOOK or aftermarket that will work. If you live where there is a Lowes home improvement, they stock a big selection of metric screws and might (maybe) have soemthat will work(They will have the length, the issue is head type)

Without knowing the model of pedal I can't help you more specifically, but sometimes the issue isn't the pedal...it's the shoe. Are they new too? If so, a good trick to get the internal plate closer to the sole of the shoe is to find a washer that fits the bolt and screw it in without the cleat. Also make sure if there is a mounting plate that it's turned the right way. Just installed some for a customer that was struggling and he had the countersunk side the wrong way.

If the bolts still won't reach, you can also try the same trick with a longer bolt of the same pitch (even if it's not the same type). Fish around in your spare parts and find a bolt in the same length range, then add washers to suit. Position the cleat where you want it and bolt it down. This will often bring the cleat and interior plate together enough to get your other proper bolts started. Once they're in, replace the temp bolt.

One final tip: After a while those bolts tend to get very rusty and packed with dirt, so add a little anti-sieze compound to the threads when you install for easier removal later and no slippage. Beeswax also works, and you can use it to fill in the hex hole to keep mud from packing in there.

I'll give an older bike shop a try for longer bolts and try your trick to pull the plate on the shoe closer. The pedals are Shimano SPD and the shoes are new Cannondale RS-1000 (by Diadora).