Figured I could make a post how I make some of my tooling for the lathe. maybe is it could be of use those who want more shapeable tooling that is bit harder then hss or make some one off tooling for a task.
You can use scrap carbide or pre made braze on inserts the process is basically the same. I happened to order some of cheap raw inserts off AliExpress.
--- AliExpress carbide
Chinese carbide grades and recommended applications
--- Grades of chinese carbide
I had some 1"x.5" cold rolled steel laying around that I used for make couple new cutters for my buddies lathe. He needed the holders to be .75" tall to work best for his tool post holder.
I used a .75 HSS end mill from kms tools to mill a slot for the carbide to sit well supported in and it also happened to be radius the inserts were formed which was nice.
The inserts already has the reliefs shaped into it so I just had to mill the slot flat, Then just pick a depth of cut and offset so the insert sat nice a snug in place. Just had to make sure it was a right height my buddy didn't have to shim the cutter every time to use it.
Next step after I got the insert how I wanted it. I threw it in the vise at a funky angle so I could just smear some solder paste on it and stick the insert on the bar stock and it wouldn't fall off once I started heating the new tool.
and what it looks like after freshly brazed into place. It's basically the same as soldering copper pipe just a bit hotter. Heat it up enough the flux turns glassly and dip the solder so it flows around the carbide. If it just balls up on top it's not hot enough if you get it too hot all the flux will burn off and the solder won't flow were you want it. Once the sweet spot is found just add enough solder it goes around the carbide insert which isn't very much probly around .5" to .75" of 1/16 silver solder.
I used silv alloy A-56 and white bazing paste which can be melted with propane hand torch but I would recommend map gas or a plumbers acetylene torch or better yet oxy fuel torch or propane and oxy torch. Another option is induction heater if you happen to have one laying around.
I used a oxy fuel torch for the two new cutter I made as that's what I had access to.
canadaweldingsupply.ca
Anyways after the cutter was cooled down and cleaned up could not help but make a couple test cuts on some hot rolled steel round stock. This was the results with out doing anything to the inserts. 1.5" round stock at 720 rpm and lightish cut
Not too bad considering the insert is factory rough. I imagine if a guy polished the cutting surfaces could increase the cutting quality but it's probly only gonna get sharpened on bench grinder with green stone so this finish is good enough.
Anyways I hope this helps someone out who may not realize it's not that hard to make custom carbide tooling or give a broken carbide endmill or toss away inserts a new lease on life lol.
You can use scrap carbide or pre made braze on inserts the process is basically the same. I happened to order some of cheap raw inserts off AliExpress.
--- AliExpress carbide
Chinese carbide grades and recommended applications
--- Grades of chinese carbide
I had some 1"x.5" cold rolled steel laying around that I used for make couple new cutters for my buddies lathe. He needed the holders to be .75" tall to work best for his tool post holder.
I used a .75 HSS end mill from kms tools to mill a slot for the carbide to sit well supported in and it also happened to be radius the inserts were formed which was nice.
The inserts already has the reliefs shaped into it so I just had to mill the slot flat, Then just pick a depth of cut and offset so the insert sat nice a snug in place. Just had to make sure it was a right height my buddy didn't have to shim the cutter every time to use it.
Next step after I got the insert how I wanted it. I threw it in the vise at a funky angle so I could just smear some solder paste on it and stick the insert on the bar stock and it wouldn't fall off once I started heating the new tool.
and what it looks like after freshly brazed into place. It's basically the same as soldering copper pipe just a bit hotter. Heat it up enough the flux turns glassly and dip the solder so it flows around the carbide. If it just balls up on top it's not hot enough if you get it too hot all the flux will burn off and the solder won't flow were you want it. Once the sweet spot is found just add enough solder it goes around the carbide insert which isn't very much probly around .5" to .75" of 1/16 silver solder.
I used silv alloy A-56 and white bazing paste which can be melted with propane hand torch but I would recommend map gas or a plumbers acetylene torch or better yet oxy fuel torch or propane and oxy torch. Another option is induction heater if you happen to have one laying around.
I used a oxy fuel torch for the two new cutter I made as that's what I had access to.
Harris Safety-Silv 56% Silver Solder Brazing Alloy
Harris Safety-Silv® 56 56% Silver Solder Brazing Alloy High silver content alloy; makes premium-quality brazes. Free-flowing with unsurpassed capillary attraction and deep penetration with high ductility. Chemical Composition: Silver(Ag) 56% / Copper(Cu) 22% / Zinc(Zn) 17% / Tin(Sn) 5%...
Anyways after the cutter was cooled down and cleaned up could not help but make a couple test cuts on some hot rolled steel round stock. This was the results with out doing anything to the inserts. 1.5" round stock at 720 rpm and lightish cut
Not too bad considering the insert is factory rough. I imagine if a guy polished the cutting surfaces could increase the cutting quality but it's probly only gonna get sharpened on bench grinder with green stone so this finish is good enough.
Anyways I hope this helps someone out who may not realize it's not that hard to make custom carbide tooling or give a broken carbide endmill or toss away inserts a new lease on life lol.