Hi Guys!
I think I already know the answer.. and its Carbide..... BUt I want to run this by you all first.
SO.
I decided to get started on the Tool holders for the QCTP tonight.
I had previously purchased a chunk of steel... grade zero tool Steel I gather. It was a drop.. and it is 3" wide by 1" thick, and 26" long. Sooo I will be cutting a Slot down the length of it.. then dovetail it... then flip it. Cut 1/2" slots across it. Then into the band saw to lop off the individual tool holders... then back into the mill to get holes drilled and tapped.
SO
I tram the head of my mill. 1 thou over a 24" sweep.. I think thats gonna be ok.
I lock this beast of a slab of metal down onto my CLEAN (yes I spent last weekend cleaning the area around the mill and lathe of swarf... 5 Gallon bucket of packed down swarf) Mill surface.
I make sure to get it perfectly square and true with a dial indicator as I traverse the mill.
I chuck up a .75" SIDE MILL... (two flutes GOLD colored cheapy titanium coated Fleabay brand new cutter)
I bring it down with a piece of paper under it, till it JUST touches the work piece.
I adjust the mill stops so the powwer cross feed stops with the end mill JUST outside the work piece on each end.
Move the 5 gallon bucket that is the coolant pump and resevoir over to the mill.. hook it up, so it floods the milling bit nicely.
Hook a drain from the mill table to another clean bucket to catch the used coolant.
Fire up the mill around 1150 RPM.
Bring it over the work... raise the table so it just barely cleans the metal.
then I turn on the coolant, and crank that thing the length of the work. SMoothly and slowish.
I end up with a nice smooth clean evenly cut "channel" in the metal. maybe 2 or 3 thou.
I then raise the mill about 30 thou. ANd decide to see how well its going to cut this steel if I move slow and have flood cooling.
Soooo It cuts... tip gets hot.. little smoke from the WD-40.. but not too bad.. I can still see the tip, and the spray etc. It SOUNDS ok.. nice smooth uniform cutting noise.
I get into the work about 1.5 inches and the sound changes... it begins to go higher pitched.. no chatter.. but it begins to go higher pitched and starts to squeal.. So of course the ultra slow manual feeding I was doing.. I slowed down and backed off.
I attempted to re-start the cutting twice.. and it just squealed and smoked once I very carefuly brought the cutter to the work piece.
I decided 30 THou was too much so I backed off to 15 Thou. Tried again.. and it squealed a TINY bit when I started.. but only a tiny bit.
I slowed down my cut even more so I was barely turning the handle... and I was getting little 1mm chunks of steel uniformly coming off the part, with a small amount of smoke from the coolant.
I then put the power feed on its slowest setting (which isnt moving) and then turned up to the super slow crawl of a speed I was feeding it at.
The table ultra slowly crawled across under the cutter.. uniform sound.. uniform chips, and a tiny tiny amount of smoke from the coolant. The tool bit was bathed in coolant, and staying cool.
Now
The work had a odd shape to the cut.
It had a real smooth center.. and on each side of the cut it had a... prolly 1 or 2 thou step. -----_______-----
Knowing this wasnt right.. I thought about it as it slowly crawled along... and realised it wasnt the head out of tram.. because that would just cut funny.. leaving a swirl mark of some sort... this wasnt.
After the cutting was done I pulled the tool bit.
Looking at the end.. it had eaten 1/3 of each flute back about 2 thou, but the stronger center was unblemished.
I changed to the other 3/4" cutter I had... a END MILL (4 flutes.. but center cutting also) and moved that baby over to the work.
I tried to make a 5 thou cut.. and it screamed at me like it was going to explode soon as the tip touched the work. Also followed with a HUGE plume of smoke.
I sped the mill up to 1750.. it screamed louder, and more instant smoke.
I slowed it to the slowest speed and it chattered and squealed and smoked.
And yes I am talking move it to the work and ever so slowly slowly slowly slowly touch the work. (I learned to be careful with a smaller cutter when I started by moving into the work too fast and the small cutter exploding..... so I am very very very careful now... and lucky too thanks)
SOOO
My question.
Should I buy a carbide Side Mill?
As this is a bar of tool steel.. from what I read about Mills.. the Gold colored TiN ones are fine for brass and aluminum.. but once you move to stainless and or tool steel they are complete crap.
Carbide 3/4 Hogging Mill... (Needs to be run at high speed.... high speed being how many RPM?)34 Bucks..
http://www.wttool.com/product-exec/product_id/31610/nm/Carbide_End_Mills_WT_Import_A Solid Carbide 2 Flute (picture shows 4 flutes) is a bit expensive at 50 Bucks!
http://www.wttool.com/product-exec/product_id/32044/nm/2_Flute_Solid_Carbide_Single_End_Mills_Import_Or should I simply buy a Indexable tip tool such as this? 16 Bucks, plus inserts..
http://www.wttool.com/product-exec/product_id/33787/nm/Indexable_Carbide_Insert_End_Mills_WT_Import_Or a set for 50 Bucks
http://www.wttool.com/product-exec/product_id/33822/nm/Indexable_Carbide_Insert_End_Mill_Sets_WT_Import_Thoughts and opinions appreciated
