Anyone know what's best to cut slide rails on 1911 Sarco frame? I do not have my slide here yet, but a machinist is willing to trade the bit to me for teaching him Tig welding aluminum.
Should I use a Woodruff keyseat cutter? Slitting saw? End mill with frame mounted on side? I shy away from the endmill cuz I can't do both sides at the same depth.
Also, what size should I use? Would rather be undersized and take two cuts to match to my slide. What's the USGI dimmension for slide rail width?
Patch, a 3mm keyseat cutter or endmill works. I've done it both ways. The keyseat cutter does take less setup, but costs more. If your just going to do the one the endmills are OK. But who can do just one?
I used a endmill, a 3/32 carbide one. Lots of photos of setups in the 1911 80% FAQ.
IMO investing in a keyseat cutter is worth the cost.
One setup to align the top of the frame and both rails are cut perfectly parallel to each other.
For best fit get your buddy to measure the slide rails and then cut the frame rails to suit.
I find the keyseat cutter is a bit more forgiving of any play in the mill table and gives a better result than a itty bitty end mill that I invariably break anyway.
A 3/32 will need 2 passes I think. I used one about that thickness years ago to do rails in 3 passes per side.
First pass only going in half the depth then checking to make sure the second cut would bring to the correct depth. Learning how accurate the dials on the machine were was the reasoning behind doing that in stages.
Then move the cutter up or down as needed to do a final sized cut the full depth.
I did break that cutter after a few years through mis use. Learning the wrong and right way to use mills can be expensive.
Later on I got some other cutters cheap but they were a bit too thick.
I started off with a 1/8 cutter and chucked it in the lathe and then used a dremel to grind the cutter head down to a single pass tool.
Trying to remember what thickness I used but it was some where around 0.115 thick to match the slide I had at the time. But check the prints for correct specs.
If I was in your position I would get a 3/32 X 3/4 diameter keyseat cutter and do the rails in the 2 or 3 as the case may be passes.
Make sure the frame is solidly secured to the table
take it steady on the tool speed and feed in rate
coolant will help stop the tool getting over hot and getting blunt also
The print is .119 +.002
Although I just bought a new Fusion frame that measures .114
The Kuhnhausen #2 1911 book suggests .114 as a match dimension for getting a good fit with whatever slide you fit it to.