Hi All, I am about to start he next project, a magnetic knife bar for a knifemaker. I need to pocket about 1 x 16 x 5/8th inch of maple and am thinking of switching to a 1/4 inch end mill. will this save much time? I assume I have to slow things down.
thanks
Ben
Maybe if you have the torque and rigidity for it. Hard maple seems REALLY hard to me, soft maple not so much. I have a few 1/4 inch endmills, but on my mpcnc with hard stuff, I found enough bogging and flexing that I ended up decreasing the step over anyway. I might get after it a little harder now, but who knows?
If you have the tools, I say go for it. Going to take some experimentation, though, and depending on how many you need to do, might be faster to go with a tool setup you already know. If you don’t have a tested feed/speed with the smaller tool, might be moot.
What kind of end mill? If it’s an aggressive roughing style, you’ll be able to pocket that stupid fast. One quick tool change to a finishing tool and presto.
This is the back side of a magnetic knife bar. The pockets can be on the rough side. What do you suggest?
My suggestion is that since this is probably a one off piece, that whatever you have handy will be more than adequate so long as the feeds and speeds are alright.
Roughing end mills are generally low flute count with aggressive, serrated looking flutes which are designed to reduce cutting forces and rapidly clear small chips.
It’s worth looking into if you see a lot of deep pocketing in your future or plan on working with some metals.
I don’t know much about machining wood yet but I imagine a high speed steel 1/4" end mill can probably rip through wood pretty fast when you have 30k RPM available and you aren’t worried about tool deflection.
Edit: Also, if you’re feeling a bit spendy, Freud makes some really good router bits that will fit in a 1/4" collet that will take very wide cuts, not sure how big but definitely there is a half inch one and after using one I think that they do an excellent job!
I use a 1/4" endmill on my MPCNC. It’s a single flute bit. I haven’t tried to cut hard maple with it, but it has worked well in Red Oak and Iroko for me.
I use 1 flute 1/4 inch in oak poplar cherry at 3mm DOC and 500-600mm/m with the speed turned down just a bit on th edewalt
So far 6.8 mm holes 18 mm deep with 300mm/m feed and 400 mm/m plunge with a 6mm lead in in cherry works great 2 flute 6mm end mill about 20,000 rpm
you need to experiment though i have a 20 x28 1 in stainless setup that is a lot stiffer than the EMT 24 x30 setup I had I also run a 3 driver arduino a dn GRBL setup
Thank you. My bits came in last night. We will see what I can do.
how did your cutting go?
Thanks for checking.
I have been working on my v carving, next up I will work on the pocketing. It is the same project, magnets recessed in the back and the clients logo in the front.
I think it went great. I took the milling basics settings for 1/8th inch bit and changed to 1/4 inch bit. I experimented a little and was able to up things to 6 mm DOC and 25% overlap.
That is where i started and 1/4 inch and 6 mm have been working great for me with the MPCNC poplar ,oak ,cherry ,pine,walnut all about the same. The machine is awesome it has passed every thing I expected of it and more. Just remember what it is and it won’t disappoint you and it will do everything you ask just figure out how to ask it 
This has been the most fun I had since Lincon logs