Just looking at a well looked after old Craftsman router 25070 model and was wondering if it is just 1/4" or can it take 1/2" shafts?
And excuse my ignorance but why are there two different width shafts in routing?
Judging from the parts breakdown, I'd say it's probably only 1/4" diameter bit capable. The reason for larger bit diameters is due to the size of bit (overall outside diameter) larger ones require larger shanks on the bits, to prevent the bit from shearing off during routing. Larger bits are much stronger, and can withstand the side load forces more adequately without flexing or breaking. That should be a good router for the general stuff, but you may want a more powerful router with removeable collets for the bigger projects.
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