The part of the pasta machine that you want to use is just the sheeting part. If you get one from Michaels or Joann etc.. that is the only part they will have. The spaghetti part is an attachment that you don't need. You just slice bits off the block of clay a little thicker than the setting on the machine and run it through. Then double it up and run it through again. Eventually you wind up with sheets. This is useful for more than simply mixing clay. It is useful for making uniform sheets for costuming, capes, etc. also when combined with a small cookie cutter or like item you can know that the amount of clay for both ears, hands, feet, etc. and so forth is pretty much exact. I understand the desire to save money and do it in your hands... but if you are doing a lot of stuff the time saving and stress on your hands saving is well worth the price of a cheapo machine from the craft store. I recommend the Sculpey machine over the Amaco or store brands (nicole, darice, etc.)
Some tips:
Don't be afraid to take it out of the box at the store. The quality control is not great and just put the handle in and make sure it rolls smoothly and both rollers are turning.
When you do mixing or softening of the clay use the 2nd thickest setting as opposed to the thickest. The gears will be a little more engaged and it will prolong the life of the machine.
Don't try to force a really thick piece through. Ideally the clay being ran through the machine should be no more than double the thickness of the the setting on the machine.
Wait for a 40 or 50 percent off coupon. Sign up for emails from Michaels, JoAnn, A.C. Moore, etc. and they will send these to you, or check your paper on the day the sales circulars come out. Most of them also will honor the other stores coupons.
Trust me, if you do a lot of mixing and conditioning, or want equal proportions, or are doing costuming... a pasta machine will save your time, hands, and sanity.
Tombo
The Ultimate Sculpting Tool Page