[ShorelineCNC]

Hi all,

I have a Techno HDS 60120 with OSAI controller, becker vaccum pump and automatic tool changer. I work in a cabinet shop making custom kitchens. We have been making shaker style doors on the cnc but it is a constant battle to get good results. I have watched all the youtube videos, read thru all the forums here, reddit, and facebook and I still cannot figure anything out to make these cuts better. Ideally my boss wants them to come off the cnc "perfect" so that they can be sent right into the paint booth, and not be sanded at all. This cut pictured is what I get when I use the toolstoday cut file and recommended bit set (https://toolstoday.com/free-mdf-simu...tomizable.html).

Why am I getting so many lines through my cut and why when I switch bits it is not cutting at the same depth. I was told that everything should be coming out smooth and "perfect" since I have an automatic tool changer and I'm not resetting the z between bits. Any insight to what I am doing wrong, or what is possibly wrong with my cnc would be greatly appreciated.

[Jim Dawson]

Your boss is probably dreaming, but it may be possible to make it better. But paint ready? I not sure.


First the long lines on the cutout. Looks like your head is out of tram so the cutter is cutting heavy on one side.

Then it looks like the tool Z offsets are not correct. If you set the offsets correctly the cuts should be the same depth between the two tools.

[peteeng]

Hi - Do you set your tools? If not talk to the toolsetter and find out what he is setting the tools to. Then check the tool library and confirm the library offset is what the tool is actually set at... Then tram your machine as Jim says. Then I think you'll be close but you will still need to sand... Do you seal before you sand? This would be a good plan... Peter

[routalot]

I agree with the points raised and solving those issues will be a big help.As for getting a paint ready finish direct from the machine,has anybody consistently managed this?I've never encountered MDF that didn't differ in texture as you dig into the sheet,near the surface it always seems to be denser and less prone to tearing and then gets more fluffy as you near the centre of the sheet.A sealer coat and some sanding always seems to be needed.

[CitizenOfDreams]

What they said above.

Check your tram (so that he spindle is exactly perpendicular to the worktable).

Measure and set the tool length (so that all your tools cut at the same height). It should be enough to do it just once. If your spindle is clean and working properly, tool height should stay the same between toolchanges.

If you are using multiple passes, try making the final pass more shallow.

That should improve the finish, but your parts will likely still need sanding before you can paint or laminate them. That's perfectly normal for MDF.

[routalot]

I'd be interested to know if the backs of the doors are even close to being flat after machining.My experience of removing large volumes of material from MDF sheets is that the vacuum may hold the sheet flat while the power is on,but once the vacuum is switched off the panel springs to a new and different shape.Have you ever laid a good straightedge along the back face?