Using a 4 inch mini circular saw blade, enlarge the Arbor hole to work with a grinder
Step 1: Drill Out the Arbor Hole to Fit on Your Grinder
The mini saw blade I bought came from harbor freight for five dollars as a replacement blade for the mighty mite table saw they sell. I took a 7/8 inch drill bit and drilled it out to that size to work as a blade in a grinder. The hole that was already in the saw blade cause the bit to pretty well self center itself. You could get it to an even closer precision by tracing out the larger arbor circle and carefully enlarging it with a die grinder or Dremel tool as they are also called using a carbide cutting bit.
Step 2: Make the Rubber Washer
The more expensive grinders come with a rubber washer fabricated permanently into them. I made one from an old bicycle tube. Safety first. Be sure to wear the proper personal protective equipment if attempting this tutorial and whenever using power tools. I never like to be without my goggles and ear muffs.
Step 3: Enjoy!
Put your new wood cutting blade with the rubber washer in your grinder as you would with a cut of wheel. Enjoy your new mini circular saw. It is much lighter and more versatile in that way than a heavier skill saw.
Step 4: Apology
Sorry about the lack of photos and detail. I took a bunch of pictures with one of my android phones which is temporarily misplaced. When I find it I will amend the instructable with photos and accompanying explanations. Until then, enjoy the youtube video and don't be afraid to think outside the box. Just because you are poor does not mean you can't have a hooked up workshop.
Step 5: Video
https://m.youtube.com/watch?v=9PzcX6rbTYg There is the url to a guillotine video of the saw in action. It's the mobile url so it has the m. In the address for mobile. If it doesnt work on the instructable or with the url just go to youtube and type in: grinder to mini circular saw. Should pop up.