Hello Mr. MacMunn,
You are correct, the cost of materials isn't always what it seems. One way to look at that cost is if a person does not have the skill set or knowledge to cut a less expensive grade of material, then they are forced to cut more expensive materials to achieve the desired result.
Moving on to "Conquering the Fuzzies"
What started me on this thread was looking at some of the commercial products that are cut in pine and sold in retail stores without being covered in fuzzies. An example of this would be the products that come from Walnut Hollow Farm in Dodgeville, WI. I have personal knowledge of this business, having been in it several times. They produce literally tens of thousands of pine items, trust me, they do not sand their router cuts. They obviously make money doing it. So much for pine not being a viable material.
I have been continuuing to make progress on conquering the fuzzies. In the last week or so, I spent some time tuning up my machine. Something most of us tend to neglect. I am now programming my cuts at 400-500 IPM. The fuzzies have virtually disappeared.
Below is a pic of a toolholder I cut yesterday out of Lowe's 2X8 material:
Yea, I know, but I was getting tired of the clutter on my bench and hunting for the right bolt.
The pic you see is exactly as it came off the machine, no sanding at all. Normally in the rounded corners in the pockets the fuzzies would be a disaster, not after programming at the higher feedrates. Of course, the machine did not go around those corners at 500 IPM, but it did go around them much faster than if I had programmed at 100 IPM.
I do not think it will have as good a result doing 3D work as the tool is quite often cutting in an upwards direction as it traverses. I am pretty sure this is going to result in some fuzzies no matter what. Later today I am going to run a test V-Carving at a high feed rate to see some results.
By the way, the "planing" cut for this project took exactly 1 min 29 sec using a .50 dia end mill traveling at 500 IPM. So a statement someone made about waiting forever to plane a workpiece because it is pine isn't exactly on the mark either.
I have this nagging thought that we see a lot of "rules of thumb" quoted that are way off the mark when it comes to CNC machining of wood. A lot of the people are using home built machines (myself included) that may not be rigid enough to cut at high feedrates, so they will tell everyone what their results have been, and others new to cutting think that is the proper cutting speed.
I built my new machine last year, I was hesitant to push it to these higher feedrates. At first I did not have much success, but then I took some time and did the proper tuning. The difference is amazing! My old machine would cut at 90 IPM, my goal for the new machine was 250 IPM. So when I reached that, I thought it was good enough. But actually, the machine is capable of twice that speed, so is the tooling. There is nothing special about my machine, it is a typical 8020 build with Gecko drives, etc.
Maybe I have a strange view of this forum? Over the last 5 years I have received a lot of ideas and help from the members, not to mention incredible service and support from the Vectric Team. So my idea is that when I come up with a way to cut faster, better, or solve a problem, post it here and share it. I never think to myself "Why would anyone want to cut that material?" or "What is the point of cutting that fast?" or "They are not charging enough!" What others do is their business, not mine. I don't view this as a sign makers forum. As I look at the posts, I see robots, guitars, gun grips, clocks, wall carvings, concrete molds, inlays, cabinets, the list is endless! That is one of the things that makes this the best forum on the internet.
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