Thread: Fluffy mdf
Unless the MDF is damp you shouldn't get fluff no matter the manufacturer. If you getting fluff then your cutting wrong for the density of that material, the Medite MR will just be a different grade or density and you've got lucky on Feeds etc.
20mm/s is far to slow for MDF not matter what size cutter or DOC and even if you were cutting at 3000 Rpm which again is ridiculously slow for MDF or wood it's all wrong.
Every machine needs feeds & speeds tweaking to suit it's build but even allowing for that these feeds are way off. I think you'll find the cutters will wear very quickly.
Give some details of cutter and an idea of the strength of machine, also spindle your using IE: picture and will suggest some feeds to try.
Last edited by JAZZCNC; 17-08-2013 at 06:15 PM.
Just to give an idea.
With my DIY cnc router, I can do 18mm MDF cutting at around 3-4m/min, full doc @ 24k rpm, with a 10mm twin straight flute TCT cutter.
I am left with clean cuts, no fur's etc.
Last edited by Mad Professor; 17-08-2013 at 06:24 PM."If first you don't succeed, redefine success"
Now that's more like the speeds and with a decent sized cutter, thou I would suggest doing faster in 2 passes for increased tool life.
I always work on 50% cutter Dia has max DOC thou in soft stuff like this I'd do 100%.
Last edited by JAZZCNC; 17-08-2013 at 06:47 PM.
I think a lot of people under estimate the importance of speeds and feeds and how they affect tool life.
Mad Profs calc are to run at 50 to 60mm/sec. What would you recommend with a 6mm twin straight fluted bit. Also would it be possible to do this in say 3 passes? Still not sure what the VFD readout at 3000 means. The readout can go to 4000 when up full. The max spindle speed is 14,000rpm according to the spindle spec.
I agree that speeds and feeds will have a big influence on tool life. Obviously I am looking for the best running conditions for longest tool life on this type of mdf
Maybe the VFD is not setup correctly?? It could well be that your cutter is only spinning at 3000RPM! Have you got a tacho so you can check the ACTUAL spindle speed? Or maybe it's Watts? Is it a 4kW spindle?
Last edited by birchy; 17-08-2013 at 08:09 PM.
Had a look at the VFD display and its set at Hz. There is a light to read in rpm but haven't figured out how to display this yet. Not being electrically minded I have assumed that 4000Hz is 14,000 rpm. Right or wrong
With 6mm cutter at 6mm DOC 13,000RPM the minimum I'd be cutting at would be 4mtr/min and that's allowing for a weak machine. If your machine is strong-ish then you'll be wanting to be around 5-6Mtr/min and could go much higher if wanted 8-9mtr/min with 14-15K rpm.
The VfD could be showing Hz but it may be 400.0Hz not 4000Hz and it's not showing the point. What make of VFD is it.?
Last edited by JAZZCNC; 17-08-2013 at 08:44 PM.
Thanks for that. Will try tomorrow. It's a Chinese machine so no idea what make the vfd is
Still no mention of the type of cutter used? I have better results using a single or two flute cutter. Using a three or above cutter results in fluffy edges on cheap MDF. Rules here is always cut your material as soon as you buy it as well, MDF that has been laying around is not good unless you buy premium material.If the nagging gets really bad......Get a bigger shed:naughty: