A story goes with this. When I was an apprentice working on the warterfront I was given the job of dismantling dozen large deck winches to send the drum shafts to the shop. They neded a keyway to mount a gypsy drum on the bare extension. I forget the shaft size maybe 4" or so. This involved a lot of disassembly, removing the level wind, brake, jaw clutch and linkage, opening the transmission, etc shipping the shaft, storing the parts on a busy deck for maybe a month, keeping the open machinery safe from debris, FOD, weather, etc. It was a couple of weeks of work for me and the first year guy assigned me. I recalled a yarn an old fart told me and asked the boss If I couid hand chisel the keyway. He questioned me closely and then said said sure but cut it a size under and show me. He exchanged a wink with his desk sergent and material man.
So we, my apprentice and I (also an apprentice) gathered the the means and went to work. I laid out the keyway margins using the Starrett thingys you clamp on the scale of your combo square and we set to work first hacksawing down the side, bay flexing (local term for grinding with an angle grinder) a keyway sized flat, We stop drilled the length to depth, kerf cut the waste to depth at the accessible end, tapering the cut to the end of the seat, square cut chiseled from there, then continued with files (spoon shaped rifflers were available from the tool room.) we scraped the sides to blue in with an undersize key, and dressed the bottom the remove the ugly. The end we treated like it was endmilled. In the end we came up with a nice clean keyseat. It took a full day but it was not nearly the ornerous task the old timer made it out to be.
The boss approved so we hand cut them all. We got a lot of tourists and suggestions. The dozen winches took maybe ten work days. My apprentice had school week so I finished on my own which slowed progress.
I was a hero for an hour, then I was put to de-slushing elevator rails and inspecting them for defects - one of the dirtiest jobs ever. No glory last forever.
Anyway we use a variety of chisels and we had a grinder right there to keep them tuned up. Most of the chisels we used were side cutting that is beveled from one side but the oither was slightly rockered. You had to dip in and out of the cut as you went along. We used a light scaleing gun to drive them. Hand chiseling with a hammer was a huge PITA but we did it when we were cleaning out corners, and going for the final bits before filing and scraping.
Most of the chisel types we used were in the Starrett set once sold in a fitted wood container. We modded cape point gun chisels to suit.
BTW, we had to hold sides and bottom parallel to the shaft axis. How did we do it? Do you think a surface plate held against the bottom of the shaft with a couple of screw jacks may have helped? Surface gage? A little tool maker"s knee? A Starrett indicator kit?
Some reference material:
http://www.osh.govt.nz/order/catalog...oldchisels.pdf
http://www.ebay.com/csc/i.html?_nkw=....c0.m270.l1313
http://chestofbooks.com/crafts/popul...hisels-308.png Misc cold chisel configs
http://www.roseantiquetools.com/index.html Interesting site for antique tool people. LOTS of catalog downloads.
The machinst trade descends from a branch of blacksmithing where metal is worked cold with chisels. The chisel types and styles were probably borrowed from stone masonry and carving. The process of shaping metal cold was so laborious it was early mechanized and from that the machinist trade and all its distributary trades and ativities were born.
When I served my time we had a separate trade "chipper" who worked with air hammers and chisels for weld gouging, caulking, etc. A good chipper was a noisy beast but highly skilled. I knew of one who over a period of years sculpted the White Rock Fairy from a block of steel using a set of five chisels he kept with him. "Hey, Jim, how's the statue going" and he'd dig out a roll of oiled rages and reveal a fist sized soon to be breathtaking work of art; a realization of the White Rock logo art.
http://www.whiterockbeverages.com/
A good chipper could split off rusted nuts quicker than you could wrench and methyl salycilate them and never damage the stud.
