just a few bits

[oldskoolron]

Ive previously said a mate from round the cnr from me works in a foundry on the real big lathes .He has given me some milling endmills that have a lil bit of damage to the bottoms of them so i tried them with him present on my mini mill .They all 3 bits in all worked ok if i only use the side of them to cut alloys an steel
He also gave me a block of crobalt [spelling may be wrong] so the other week I attacked it with a ultra thin 4inch disc in my grinder so far i have 4 x 3/8 x 3inch long peices Ive still got to cut the other bits .Started other night but ran out of cutting discs about 6 discs to cut 8 peices .
today he came over and gave me these [I think he said carbide] bits but they too big in body for my tool holder
 
My question is ...can I put the new tools in my mill and knock them down to size ..will it weaken them?
Heres a pict of what he has given me an he said he has some more chunks of crobalt cheers in advance for the answers ..oops sorry bout caps my bad
 
[edit caps DaveH]

[Dr Stan]

How much too big are the carbide cutting tools?  BTW, yes they are carbide commonly called cemented carbide.  It would be a good idea to ask him what grade they are.  From that you can find out what material they are designed to cut.

on edit. Actually all you have to do is look at the side of the cutting tools to determine the grade. It should be stamped on and include RH hand or LH.

I recommend making a holder for your quick change tool holder that will hold these tools assuming your friend will continue to supply them.  That way you only have one item to mill instead of multiples over time.

[PixMan]

If those are 3/8" square pieces of tool steel, then relative size of the brazed (cemented) carbide turning tools would be 5/8" or 3/4". They will likely be marked as "BR 10" or "BR 12" (number representing 1/16ths of an inch), with a grade making following that. Depending upon what company made them the grade marking might be in ANSI carbide class grading of C-2, C-5, C-7, etc., or could be a manufacturer grade such as 883, K21, K68, VC2, etc. I can usually tell maker by the grade if it's not an ANSI nomenclature.

[oldskoolron]

I only have the older style tool holder but do have a quik change one with 1 holder ..if I make it fit that id still have to take off 1/4 inch off the tool or if I use my normal one will need to cut it in half to fit .I think the best way would be as mentioned an set it up in the quik change so I always have it set up correctly an not have to stuff around shimming it ect
cheers

[PixMan]

So are there any markings on those red painted shanks or not?

[oldskoolron]

sorry mate health been bit bad lately
the marks on it are  BR2020   ATUCA
there the only markings on em

[EdK]

I think the BR20 indicates that the shank is 1.25".

Ed

[oldskoolron]

I measured it ed and its 20mm thick ill ask oldmate when I see him next what they for I think he said cast iron an he said I be ok using them on mild steel and alloys seein im a beginner basically

[bollie7]

(09-26-2016, 09:28 PM)oldskoolron Wrote: I measured it ed and its 20mm thick ill ask oldmate when I see him next what they for I think he said cast iron an he said I be ok using them on mild steel and alloys seein im a beginner basically

Ron
Obviously I have no idea what your lathe is but if a 20mm shank tool wont fit then I'd assume its not a real big machine. Depending on what your lathe is you might find it doesn't have enough power to run a carbide tool very well. It might not be worth the effort to modify the tools.
I only have a small belt drive lathe (can't remember the size atm) its a McMillan which is a rebadged Lontain from the early 1980's.
I have a box with a lot of large, insert carbide tool holders and tips which I have had for at least 20 years (from when I worked on the tools for a living) in the hope that one day I would have a lathe big and powerful enough to run them. I've recently accepted that unless I win lotto, its never going to happen, so I'm slowly sorting the tools and tips in preparation to moving them on.
I've found with my smaller lathe that is easier just to use HSS tools.
regards
peter

[DaveH]

BR 2020

"USE" to mean the shank is 20 x 20 mm the red shank means it is suitable for cast iron.

B means the front cutting carbide angle is 7 to 15 degrees.
R means it is a right hand lathe tool.

You can mill the shank down to fit your lathe it will be fine.

Sometimes it is really good to be old


 
Dave