"One Tersa carbide head is retail at 20-150$+. For my planer it¡¯s 150$.?
It takes a few minutes to turn the segmented heads. You get 4 turns before the head is worn.?
You turn one carbide silent power segment, and while it may take longer. You have 4x the cutting life.
Time is money yes, a silent power cutter head potentially saves 4x Tersa changes or in my case 450$ per full blade change."
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You're oversimplifying,? and erroneously calculating the time and costs.
First -? tersa knives have two sides. so you get two turns before it's ready for the trash.
2nd -? I'll bet you cannot turn (and torque !) an entire 12" + cutterhead's worth of segments in a few minutes.? No way.? Maybe an hour if you're real efficient.??? 5 min. tops on 4 tersa knives and you don't need to worry if your torque wrench is still calibrated. And it the same whether you have a 6" knife or 20" knife.
Third,? you haven't figured the cost of a full set of segments in cost per rotation.?? How much is a set ?? Divide by four for its cost of rotation in your scenario. ? ? And,? as hinted above - your Tersa cost per rotation is $225 - NOT $450 !
While you probably don't have a burdened labor cost of $225/hr either;? I'll bet it's half that at least. So now, that one hour of edge changing time starts to add up. Pretty sure when you calculate your SP segment cost per side change it's in the $75 range.? Approx 1/3 a Tersa cost.? Add in your +$125 labor cost per edge change and it's starts to get real close in cost per edge change.?? And that's assuming you get it all done in an hour.?
While I agree that a segmented head is the cheaper alternative for those hobbyist that don't change knives often - In a production environment Tersa is almost certainly the winner.? If you change your knives every quarter - Tersa has you at the end of the year.? Change them every month and it's not even close regardless of you exact labor cost.?
