Is Trying to change blades. I got the nuts loose but now they just spin in place instead of comming off.

Lots of saws have left hand threads on the nut that holds the blade in place. It is designed so that if the saw starts up and the nut isn't snug, the nut and the blade slipping on the turning arbor would tend to tighten the nut as they slip against the force of the spinning arbor.
1. Unplug the saw.
2. Hold on to the blade tightly with one hand.
3. Put the wrench on the arbor nut and turn it in the direction you would turn it as if the wrench were turning the blade to cut wood.

If you've previously overtightened the blade, jamb a piece of wood against the teeth and the saw table top and then follow step 3.

If the motor is on the left side of the blade as you face the saw, then it's a standard right hand nut.
If the motor is on the right side of the blade as you face the saw, then its a left handed nut.

http://www.ryobispares.co.uk/assets/applets/CW1440.PDF

you need to use a long flat head screw driver and place it between two of the other studs and hold it while you loosen your nuts. do not remove them untill they have all been cracked loose. be careful you can get hurt.

Un-plug the saw. Remove the screws holding the side saw guard in place. Look at the center of the saw blade for the nut holding it in place. Take a socket wrench that fits the nut and loosen it. You'll need to take a scrap piece of wood 2x4, and jamb the teeth of the blade into it while loosening the nut. The nut will come off first and then a washer/spacer.

Reverse the order for installing the new blade. Make sure you use the proper size diameter blade (10 inch) and mounting hole in the replacement blade. Also, use the provided washer/spacers that were on the original blade and secure the nut. Spin by hand to see if everything clears. Mount the protective guard back on. Plug in the saw and test cut .

Good luck. If you are still unsure - ask a handy neighbor to help. It takes about 5 minutes to complete this task.

There is a nut that you release from the middle of the grinder wheel, (grinder blade)
This nut is flat and has four holes in it.

You will see you are providing a spanner wrench to remove this nut. The wrenches' actual name is Lock Nut Wrench. It has a U shaped end with two pins sticking out. On on each side of the U shape.

The pins are inserted into the holes in the flat lock nut, located in the middle of the grinding wheel. The wrench is laid flat against the grinding wheel, with the two pins of the wrench going into any two holes of the nut.

At the top of the Makita grinder you will see a Black button. The button is pushed down to keep the grinding wheel from spinning. Holds the grinding wheel in place, as you turn the lock nut loose. When you release the button, a spring inside pushes the button back up out of the way.

As you view the Makita grinder, Release Button towards the Back, grinding wheel towards you, the nut is turned to the LEFT, to loosen. It is a Left threaded nut.

The grinding wheel spins to the Right. Using a left threaded nut insures that the nut will stay tight, due to the direction the grinding wheel spins.

First off, unplug the saw. No need to remove the guard, though you may have to loosen the cover over the lock nut to access it on some saws.
Look for an arbor lock button on the back side of the blade housing or motor, to lock the blade in place.
Hold that down and use a wrench to loosen the nut holding the blade on.
If you don't have an arbor lock, you'll have to wedge a 1x 4 or 2x4 under the blade and hold pressure on the handle to keep it from spinning while you loosen the lock nut. Once it's loose, spin it off and remove the washer and blade, replace and retighten the nut.
Should be pretty straightforward, as long as you have no power to the machine and lock the blade from turning, not too much can go wrong.
If you want to find an online manual with instructions for your saw, please try Sears online support site at www.managemyhome.com.

I hope this information allows you to resolve this issue. If you need further assistance, please post back with a comment to this thread.
If I've managed to answer your question or solve a problem, please take just a moment to rate this post....thanks!

the nut maybe a left handed thread. the norm is righty tight. lefty loosy, try the oposite.

you have a loose nut.  Let me explain...the nut and washer that holds the blade to the motor has worked loose.  You need to remove the plate around the blade to acess it and on the end of the blade is a large nut.  Tighten it with the power off.  Sometime there is a grove on the motor shaft to hold the motor or sometimes you need to put a screwdriver into the teeth of the blade to hold in place to tighten. 

Wedge a short piece of 2x4 between the blade and the housing,
turn clockwise to tighten !