a few things
I haven't been putting on tips in quite awhile, I think my left overs are moori twos. However, even then I got a few with a rotten layer or one ruined in the tanning process. Tan wrong and you get leather that tears like rotten cardboard. Lots of pure crap leather comes out of china. I suspect some good stuff too but regardless of where the product is made if the leather came from china it is very suspect. The chinese happily meet almost any price point someone demands and cut whatever corners required to meet those prices. Cadmium in childs toys? The manufacturer(chinese) explained that the buyer wouldn't let them use lead and cadmium was the only way to meet the price requested.
OK, to recap, first issue is the leather or glue may be crap.
Second issue, trimming a tip is usually done as a scraping operation. Ninety degrees is the perfect scraping angle but often a slight negative rake is used to avoid catches and the disaster caused by "catches" if the blade is at a little too high of an angle. The thing is the more negative rake the more heat and the poorer cut. Since the blades almost everyone uses are beveled if they lay them on a flat surface to shape as is commonly done the cutting is done at a negative angle which produces heat as mentioned and quickly dulls blades. A cheat is to lay the blade on a typical high speed steel cutter which is often ground with about a nine degree rake. This largely offsets the bevel in the blade. Less heat, better quality tip finish, longer blade life. Win, win, win.
Blades are another issue. Heavy duty blades are duller than dirt when you get them, bad choice for this. Standard blades are a little better and I used to mark one each time I did a tip. I did three tips with a blade then it went to another blade holder for other purposes. Retractible blade razor knives are another issue if they are used. The blade usually has play in it which can lead to all kinds of grief. For everything but cutting boxes and such I only use fixed blade knives and if the blade isn't held tight I shim it tight.
One thing I have discovered. The coated blades and bi-metal blades are far better quality than standard blades and far sharper. I still only put on three to five tips with one but after trying the various specialty blades I found them all far better than plain blades.
Burnishing can indeed cause layered tips to delaminate. Also often you are playing with a glue saturated area in the middle of the tip and pure leather on the outside, a little more use and you are playing with pure leather in the middle and glue saturated leather on the outside. Back and forth, back and forth. With a single layer tip it is honest, it is either good or bad from the jump and you can play with it until it gets too low. There are ways to test and select single layer tips, why they are my choice for my cues. With layered tips even if you test top and bottom layers, what is in the middle?
I gathered all this information together awhile back and wrote an article, timing was bad and it was never published but I do remember all the info I assembled, figured I might as well rewrite the article here! :thumbup::thumbup:
Hu
