A question of Mdf?

Noticed when cutting small tables, the edges (even with a new bit) are very furry.

I know a compression bit is the answer but they are expensive and upper cut spirals have worked in the past.

Is it the quality of the mdf? It seems, the lighter colour it is, the better it cuts (or is that just a coincidence?)

Stuff from Builders yards, Wickes, B & Q seems to waver wildly in quality. Where do you get decent stuff at good prices?

Attachment 23217

Yes, lighter color generally indicates higher quality, often known as super-refined MDF.

I generally use downcuts.

a straight flute generally works ok for me certainly better than that

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Originally Posted by charlieuk

a straight flute generally works ok for me certainly better than that

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Does it plunge well? Know of any good prices on straight flutes?

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Originally Posted by Straker

Does it plunge well? Know of any good prices on straight flutes?

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here; https://www.toolstation.com/shop/Pow...traight/p67412

You should use a spiral lead-in because they are not designed to plunge straight down, I use them all the time.

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Originally Posted by EddyCurrent

here; https://www.toolstation.com/shop/Pow...traight/p67412

You should use a spiral lead-in because they are not designed to plunge straight down, I use them all the time.

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Thanks, but isn't that a router bit? I'm talking CNC btw.

Ha, the router bit has no idea nor cares whether you are using a router or a cnc, in fact I'm suprised you thought there was a difference. (where we are talking about wood products)

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Originally Posted by EddyCurrent

Ha, the router bit has no idea nor cares whether you are using a router or a cnc, in fact I'm suprised you thought there was a difference.

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Sorry I thought they were different. I just found a straight fluted mill bit that can plunge (specifically for CNC). Will give one of those a try. Thanks for suggestion. :)

Plunging is fine but there comes a time when you should look at lead-in moves. What CAM software are you using ?

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Originally Posted by EddyCurrent

Plunging is fine but there comes a time when you should look at lead-in moves. What CAM software are you using ?

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I would only be plunging 6mm holes and the start of the table edge. I am using V Carve and Mach 3

spiral or ramp it in, I have been getting the real cheap ones from banggood and had good results and about £1-3 each depending on size

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Originally Posted by charlieuk

spiral or ramp it in, I have been getting the real cheap ones from banggood and had good results and about £1-3 each depending on size

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Carbide or HSS?

carbide

Plunging can leave marks on the edge, ramping into the cut is a far better method.

Measure the thickness of the MDF, if it's more than nominal then it likely has moisture content and that can make it fluffy.
ONLY if it's dry, a coat of spirit sanding sealer helps to keep it dry and also penetrates and consolidates the surface making for a crisper edge.

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Originally Posted by charlieuk

a straight flute generally works ok for me certainly better than that

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Solid carbide up-cut double flutes spiral router bits are also a good choice for MDF cutting. Two large grooves can easily remove chips and keep bits in balance during rotation. They are also high temperature resistant, and tungsten solid carbide can guarantee a long use life.

If you get it in small quantities, there is a material called Valchromat which is vastly superior to MDF, and it machines beautifully. It is also coloured and great for furniture building. I'm in the process of using it to make a clock case now.