Comments
-
When I started working with spiral heads a number of years ago, I was under the exact same impression. There is only one small knife that is 15mm wide in contact with the wood at any given time and how can that require more horse power than a 13" wide blade? The answer lays in the term "at any given time". With normal spiral heads other than the V-Shear head, the knife wings overlap which means that when the last knife of one wing is cutting, then the first knife on the next wing is already cutting as well. So there are knives always in contact with the wood. Of course, this statement is only true if you are cutting wood as wide as the machine (13" in this case). If you are cutting narrower work pieces (less than 50% wide of the maximum width), the spiral head indeed requires less horse power than the original head. The head in this machine has a diameter of 2" which equals a circumference of about 6". The original blades are 1/16" thick; so they add up to 3/16" of actual work during a 6" travel. This means that the motor is in 97% of all time in recovery mode to speed up again. With a spiral head, the motor gets no recovery time at all. Here is a better example for you: Let's say you have to bring 1,000 potatoes (each about 1/4 pound for a total weight of 250lbs) upstairs. You can choose to do 10 trips with each 100 potatoes (25lbs) while taking rest for an hour in between each trip. You can also choose to take 1,000 trips with each one potato and no rest in between trips. Both options may take you 10 hours, but what option exhausts you more?
Anyways, your statement clearly indicates that you have not worked with both heads for direct comparison and you only go by what logic tells you. We have done many tests and wouldn't dare to put such statements online if they were ridiculous as you say. -
I understand your reasoning about the helical (not Spiral) cutter head requiring more power however your argument is flawed as it does not take into account the amount of load. The original blade cuts the total width of the material at once where as the helical cutter only cuts about about 10mm at a time and therefore would not drag the motor down as much, even if its constantly cutting it only has to cut a small area and therefore cannot require as much power compared with cutting the entire width at once.
Additionally, I can't agree that the blade scrapping off the material uses less power then the small helical cutter slicing. Sorry but that's totally ridiculous.
The noise difference alone should tell you that a helical cutter is more efficient. Both noise and heat is energy being wasted by the machine needing to work harder.
Your video also showed the first board was cut on setting 2 whereas the second was done on setting 1. Not a fair and accurate comparison.
I do think your V Shear would provide a better result then the original blade but I don't like the idea of the head slicing in one direction on side of the board and the opposite direction on the other side.
30m 30sLength
Spiral Cutter heads generally require more horsepower than standard straight knife cutter heads. We explain why that is and show our V-Shear Head which requires less power than other spiral cutter heads. We also show how to install these heads in a portable planer DeWalt DW-735. You can find more information about these V-Shear Heads as well as the possibility to order them on our website at: https://mywoodcutters.com/V-SHEAR-HEADS
This takes less energy.
Your test is flawed.
You claim the shelix takes more power to run, but you're testing for DB?
If you were testing for it taking more power, you should have done the following.
1. Put an AMP Meter on the power cord to capture how many AMPS it's drawing.
2. SAME thickness reduction at the SAME speeds with both blades.
3. Were the the old blades new or used? (used blades make the machine struggle more, so testing with new blades is fair)
On another note.
No woodworker who wants his planer/blades to last would take off 1/8" (Each turn of that knob is 1/16") at a time on a board that wide. That is punishing the machine and the blades.