Machining of re-bar on G4000 lathe

[prasad]

Guys,

I want to turn a piece of re-bar on my Grizzly G4000 lathe. Please advice me on type of tool I must use. I have C2 and C6 tipped tools but not sure which one is better.

Thank you
Prasad
Wynnewood PA

 

[Flammable_Solid]

Either one will work. Be careful, as rebar is not great material to machine and has lots of inclusions, so it may have some odd pieces coming off of it.

 

[Ulma Doctor]

the interrupted cuts on the rebar may be a little harsh on the cutter of any type. but if you got use carbide go kinda easy on it.
HSS would be a little less prone to breakage and you can easily resharpen with a regular grinding wheel.
you chip a carbide tip you are not going to bring it back with a regular grinding wheel.

 

[Walsheng]

I bet it would have more junk in it than late fall flea market on a Sunday afternoon. Just cutting it with a hack saw can be an adventure. And with the interrupted cuts and hard spots it's going to bang away at whatever you throw at it. I would not waste any good carbide inserts on it.
If I were to try it I think I would try a cheap brazed carbide bit and just resharpen whenever I hit a chunk of rock, piece of kryptonite or whatever is hiding in there.

John

 

[darkzero]

Yup, because of the interupted cuts, C2 would be a better choice over C6.

 

[pineyfolks]

Besides turning it, just chucking it to run somewhat true may be more hassle than its worth.

 

[tripletap3]

I don't know if this applies to your project or not, but here is a simple lesson that I learned for anyone that happens to come across this post. You can take a piece of FREE scrap rebar from your pile and spend $20+ on carbide inserts to make in the shape you want with a crummy finish or you can buy a good piece of metal for $10 and still have the original insert when you are finished.

Just a little side note on rebar. Years ago we had a rebar manufacturer that was close by, and guys were constantly getting horribly burned and there even was a couple of fatalities until they ended up getting it shut down. The molten metal would just explode out of the ladle for no reason and singe everything around. During an inspection/tour of the plant I asked why there was so many serious burns and why don't they fix it. I was told that unlike normal metal, rebar was made inexpensively due to its limited application so they used a wide variety of scrap metal to make it with. This caused the molten mixture to become unstable at times and explode. I think OSHA shut them down and they moved the plant to China.

 

[prasad]

John

You are right. It was acting strange and when I read your advice I understand its cause. Re-bar is certainly made of unknown material and has unpredictable behavior. I was using cheap brazed carbide tipped tool and one bit got chipped. I stopped at that and will not proceed.

Time for me to order good stock from known trusted source.

Thanks
Prasad
Wynnewood PA

I bet it would have more junk in it than late fall flea market on a Sunday afternoon. Just cutting it with a hack saw can be an adventure. And with the interrupted cuts and hard spots it's going to bang away at whatever you throw at it. I would not waste any good carbide inserts on it.
If I were to try it I think I would try a cheap brazed carbide bit and just resharpen whenever I hit a chunk of rock, piece of kryptonite or whatever is hiding in there.

John

 

[Walsheng]

I don't know if this applies to your project or not, but here is a simple lesson that I learned for anyone that happens to come across this post. You can take a piece of FREE scrap rebar from your pile and spend $20+ on carbide inserts to make in the shape you want with a crummy finish or you can buy a good piece of metal for $10 and still have the original insert when you are finished.

Best advice I've seen yet for machining re-bar!!

John

 

[prasad]

I don't know if this applies to your project or not, but here is a simple lesson that I learned for anyone that happens to come across this post. You can take a piece of FREE scrap rebar from your pile and spend $20+ on carbide inserts to make in the shape you want with a crummy finish or you can buy a good piece of metal for $10 and still have the original insert when you are finished.

That is a great advice. I have thrown away that piece of rebar. I am now looking for a regular mild steel or aluminum scrap. Thank you very much

Prasad
Wynnewood PA