I can't seem to get the end piece to loosen or tighten to hold my bits. how can i fix this?

sometimes it is the blade and not the clipper

Hmmm some times the counterclockwise screw that attaches the chuck to the drill come forward and that is how then it stucks the 3 parts that fix a drill to a chuck. Check if this screw come forward. If yes then destroy it and replace it... We destroy it by using a drill smaller than it (usually it is 5mm so we use 4mm bit and of course a CARBIDE one because even cobalt ones can not drill a hardened bolt)

Although you posted your question under Chainsaws instead of another tool forum, look at the end of the drill. Is there a hole surrounded by a cone shaped metal end? This is the chock, if you spin/turn it counterclockwise, the opening should widen to accommodate the drill bits, then spin/turn it clockwise to tighten/clamp down on the drill bit. Some drills accomplish this with an l-shaped key that has a small cone-shaped gear on the end that fits into holes on the chock. Some drills have a chockless drill, and you simply hold the end of the drill and squeeze the trigger to use power to tighten/loosen the bit.

Try shooting some WD-40 lubricant into the 'chuck' and let it sit for awhile, then rotate the outer part of the chuck CCW to loosen the 'jaws'. If the chuck is a keyless type, just hold the chuck and turn the reversing switch to 'reverse', then gently apply power to the trigger--that should open the chuck jaws. You will likely find that a leather glove on the hand holding the chuck will help prevent a burned hand if you lose your grip. If it is a keyed--type chuck (there will be ring of gear teeth on the front edge of the chuck), then a key with a small gear near one end is required to turn the chuck open (turn the key CCW). Hope this helps!

The chuck will not turn. So to loosen just turn the black plastic counter clockwise. The chuck will loosen. Or you can hold the black part on the chuck tight and put the drill in reverse and slowly squeeze the trigger and the chuck will loosen also. Do the opposite to put a new bit in. Put the drill in forward and hold the black part of the chuck and squeeze the trigger with the bit in place and it will tighten down on the bit.

Typically, the end of the drill where the bit is inserted (called the 'chuck') rotates to loosen or tighten the arms holding the bit in place. Grasp the top of the drill with one hand and rotate the end the bit is inserted into counter-clockwise if the bit end is pointed towards you to loosen the arms and release the bit.

If it is an older drill it may have a 'key' that would look similar to end of a phillips screwdriver on a tee that can be inserted into where the chuck and the rest of the drill assembly meet and twisted to loosen the bit.

If neither of these work post what type of drill you are using as not all hand drills are the same. Hope this helps.

If you have loosened the collet, just tap the bit end on some hard wood which drives the bit inward a little and releases it. Tighten the new bit in the regular way. Hope this helps!

I have the same drill and love it !! This series of Craftsman Drills are the first of the keyless chuck. To tighten or loosen the bit, simply pull back on the black ring tightly and hold it and simultaneously pull trigger to run drill foreward (to tighten bit). Reverse (to loosen bit). The chuck will make a loud clicking sound!! This is normal !

I hope I am understanding your question properly, if not, leave a comment. This drill *** a "keyless" chuck. If you look down into where the drill bit goes, there are metal pieces inside the black nose of the tool. Those metal parts are what holds the bit into place. The drill bit slides into the hole at the front of the drill (where it fell out from), Put the drill bit back in and then grasp the black tip (right below where you put the drill bit in). Directly underneath where you put your first hand, hold onto the piece directly below the upper part. Turn the top piece right and left and it tightens or loosens the mechanism that holds the bit in place. Give it a firm turn to make sure it is tight.

Sir,
If you look at the tensioner pulley, there is a stud on which the pulley rides, and then a large washer and a nut (which holds it on). The nut must be loosened just a bit (not so loose as to allow alot of play in the mounting) but just loose enough to allow movement - then you can turn the adjustment bolt Clockwise(CW) tighten - or Counter-CW to loosen - but leave it just a bit shy of tight, then as you tighten the nut, the pulley will straighten and tighten a bit more. I hope this is what you are referring to. Hope it helps! DD