I have been given some diamond tool inserts, but the printing on the boxes is very damaged. However what I can read is Sanvik Cormant VBMT 1103 then a bit unreadable and 1525 they are 20 mm by 7mm by 3mm thick, and have a locating hole in the middle min dia 7/64", ie will take a 6 ba bolt.I would like to buy a holder for these.
Does anyone have any information on this bit. Ie which tool holder would fit. I have looked on ebay but the holders do not seem to say what size the bit fitting is, I don't want to buy a holder and then fine these bits wont fit it!
I would also like to buy some carbide inserts for threading 11 tpi does anyone know what the coding would be for these inserts please.
any information would be most gratefully received please.
The two digits that you cannot read will be "04", "08" or "12" which represents the tip radius. The "11" (11mm) is the edge length and the "03" is the thickness (3mm). You will need a "SV" series toolholder but a quick search suggests that they are as rare as hen's teeth nowadays. Try searching for "SVJBL" followed by 1616 or 2020
The threading inserts will be coded according to holder size. For example, 16ER11W would be 16mm edge length, external thread, 11 tpi whitform. 11NR16UN would be 11mm edge length, internal thread 16 UN form. Holders for 16ER tips would be 16mm square shank or larger, holders for 11ER tips will be 10 or 12mm square shanks. I'm not aware of any smaller shanks that take threading inserts.
You want a SVJBR (right hand) for turning towards the chuck and facing, the 1212 (12mm square) shank size should be adequate but may put you above Myford ctr height if that is what you use
Missing digits could also be 02 as these very pointed inserts are often used for fine finishing where a 0.2mm tip radius works well.
You don't say what 11tpi thread you want to cut but if it's 5/8" x 11 UNC then you want something like 16ER11 UN for external or 16NR11 UN for internal as these will have 60deg thread form. if Whit then go for those in previous post
Thank you very much jasonb, most helpful, I have a bigger lathe so tool size is not a problem, with in reason. the thread is BSP, so 55 degree angle, so my idea is to use the tip for threading up to 11 tpi, I have tips for smaller sized threads. however it doesn't really matter, as I can go down with a tap or die to finish off the job. It is not something that I do often.