Are you referring to every item that comes in a drilling/routing kit, or just certain ones? I was mainly referring to the main cutting bit that attaches to the router and don't know if that's what you were speaking of.It will last a long time. But you will have to sharpen in after every use. A HSS bit dulls down cutting aluminum, even when lubed and cooled during the cut. So, if you want to do a lot of aluminum, get used to sharpening the bits after every use.
All of them. HSS (High Speed Steel) is typical of the type of steel used to make the cutting edge of the router bit. You take out of the package it is already sharp. As soon use start using it to cut, it starts to dull. After milling out a AR, it is probably still fairly sharp, but I would take a sharpening stone to it before doing another one. Same goes for drill bits.Are you referring to every item that comes in a drilling/routing kit, or just certain ones? I was mainly referring to the main cutting bit that attaches to the router and don't know if that's what you were speaking of.
^^^This^^^If you are slow and careful AND wait for the router to come to a complete stop before lifting it, they will last for quite a few lowers.
If you get impatient and lift the router while it's still spinning down, thinking "I can lift it straight up (Hint, you probably can't), they don't last as long.
Or, if you find that the depth setting changed after you locked it in and end up with the mill trying to cut more than it should be and try to just power through it you will quickly need a new replacement end mill.
Please don't ask how I know these things.
If you don't trust the depth marks on your router, or if somehow your router doesn't HAVE a depth gauge, then on the Gen 2 or 3 jigs just run the mill at half-steps instead of full steps. Taking your time IS the key on this, as it seems most here already know, so it doesn't take much to eye the router base adapter against the jig before setting the end-mill in the center-hole just to be sure it isn't going to cut too deep. A feeler gauge is definitely a way to make certain those cut-depths are consistent, but if you are careful and paying close attention to the router's gauge and the jig's depth-marks, that should be plenty good enough, and 'consistent' isn't really important for end-mill longevity, it only matters for OCD purposes... Which I am sure NONE of us here suffer from (I suspect most of us love every minute of it, it is probably our SPOUSES who suffer from our OCD! ).I've been thinking of getting (2) 1/32 inch feeler gauges to set the depth for each pass as sometimes the marks on the Gen 3 jig seem too far apart.
I'd put one feeler gauge on each side of the jog and lower the router down till the mill hits the aluminum and then move it to the starting hole