Tool marking on flat bottom area of pocket

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Sid Medlock
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Tool marking on flat bottom area of pocket

Post by Sid Medlock »

Can anyone offer any advice on how to eliminate tool marking in the flat bottom area of a pocket? I am 3D laminating a sign made of MDF, and when we laminate it, it magnifies the slightest imperfections in the tooled surface. I have checked to make sure that my router head is plumb and level. I have tried different tools. Same results every time. Also, can anyone suggest good tooling for doing this process? It seems that, no matter what I do, if I don't use a brand new tool, I get a lot of pitting in the MDF. Thanks in advance.
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mtylerfl
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Re: Tool marking on flat bottom area of pocket

Post by mtylerfl »

Using an UpCut End Mill will leave less toolmarks when pocketing than a DownCut EM. I don't think that every trace of toolmarks can be avoided completely.

Not sure what the "pitting" issue is that you are running into. Cheap (less dense) MDF maybe?
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martin54
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Re: Tool marking on flat bottom area of pocket

Post by martin54 »

I don't cut much mdf so don't have a lot of personal experience but do read a lot & most seem to say that mdf takes the edge off a bit quite quickly & I have read that some prefer to use HSS cutters rather than carbide as it holds a sharp edge better so may be worth you giving that a try.

Are you sure your not running your bits to fast, nothing blunts carbide bits faster than over heating them. Are you using a bit designed for bottom cutting, if you do use a bottom cutting bit then I think you need to ramp in rather than plunge, I tend to ramp in most of the time anyway. You can reduce stepover which should give a better finish but the trade off is the extra time it takes to cut.

As Michael has already said it could be the grade of MDF you are using, not all sheet materials are made equal :lol: :lol: You could try a few different brands which may not be that easy to do as there aren't generally any markings on it & suppliers probably won't tell you where they buy it :lol: :lol:

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