I have a Holtzer Model 1250 panel saw and am experiencing a lot of chip-out, front and back. Of course I have changed the scoring knives and the blade I have in now only has about 20 sheet of 3/4" melamine under its belt (new blade). I had the tech in to the tune of $550 and all was well for a while, then the chipping started again. He says it's probably the melamine, but I use Duramine and I'm told it is one of the best. Is anyone else experiencing similar problems with their Holtzer machine?
From contributor T:
It might be the melamine, but it might not. I say that because we use the same board and usually it's pretty good. Our last two units seemed to fall short in quality. We had more chipping than we had seen before and even had melamine pop off the board in some cases. I've been meaning to call in their rep about it.
On the other hand, what type of blade are you cutting with? The best (we've found) is of course, hollow ground, but only when new. After you have them sharpened, forget it. We settled on triple chip with (I believe) a slight negative hook angle. We get some chips, but not too bad, and not much different after sharpening. The other thing to check is your plunge depth. It affects the angle of attack on the board. Also, sometimes less pressure on the knives is better than more pressure. Another comment (depending on the tech you got), double check that your column and grid are parallel, and that your board it consistently tight to the grid. If not, check the bottom board (if your machine is like ours) that is supposed to be in line with the grid, just above the bottom shelf. Ours was spaced out slightly with a shim behind it. We had to pull it out and remove the shim so our board would lay flat to the grid. All that said, from our experience, 20 sheets fully processed probably isn't bad. I know it depends on the sizes but that might a lot of lineal feet of cutting on that blade. I can't remember if we get more or less between blade changes.
Anyway, to answer your questions, I use a triple chip blade, designed for melamine. Additionally, I have about 2mm of "plunge" with the scoring knives, which I think is recommended. I'll change the blade and see what's going on there. It's unfortunate that they aren't very good when sharpened at about $80 a shot new - that does tend to raise the cost of doing business. I guess I better pay more attention to cost factors like this when preparing my bids.
Do you have preference in blade manufacturer, number of teeth, and type of blade? By the way, I did make a mistake in my initial question. The saw model is 1265S vs 1250, not sure where that number came from.
Comment from contributor A:
We have been using triple chip blades to cut melamine for about 20 years. When we have chip out it's either the blade is dull, the scoring blade is dull or set too narrow, or the panel is shifting slightly when being cut. We have an excellent blade man and our blades cut well all the time. You might check around for other sharpening people. There is a huge difference between and person passionate about sharp and one who is just sharpening.