Posted: 3/1/2010 2:16:38 PM EDT
| I am building my first 80% lower and for a first project I bought a cast titanium receiver for the project. I have come to the conclusion that titanium is very hard ( I knew that to begin with prior to my project). I am being very careful so that I do not break off a drill bit in anything important. The other thing is that the titaniumsparks made a snapping sound as I ground on it with my little grinder. I believe it is rapid oxidation with the atmosphere as the sparks shoot past my ear. Sort of a neat sound. |
|
Bradleyswine...is the titanium hard, as in brinnell hardness, or is it tough as in it doesn't cut cleanly or easily? Just curious...if it is hard, then harder (tungsten carbide would be good, but if it's tough, well, I can't recall if it was heavy cuts to cut well or fast speed. I'm wondering because I've got some thinking on something else to wonder about. |
|
Quoted:
Very cool. Where did you get the cast titanium receiver? I been wanting a ss ar receiver but seemed to have missed the boat on that. 43sec with google: https://www.vbd.com/noc/shop/products_detail.asp?CategoryID=29&ProductID=286 |
|
I have come to the conclusion that titanium is very hard ( I knew that to begin with prior to my project). I am being very careful so that I do not break off a drill bit in anything important. The other thing is that the titaniumsparks made a snapping sound as I ground on it with my little grinder. I believe it is rapid oxidation with the atmosphere as the sparks shoot past my ear. Sort of a neat sound.
Titanium is hard but machinable with readily available tooling (carbide), use plenty of coolant to aid with tool life. It is also a flammable metal and extremely difficult to extinguish when ignighted. Don't allow chips or shavings to accumulate on the work bench. The little sparks off of your grinder arn't just rapidly oxidating, they're literally exploding into flame. Watch your temperatures while grinding & try not to get the metal hot enough to turn different colors. Especially colors past a medium blue. MLG |
|
I wanted to try the titanium as my first just for something different.
I am using the titanium coated drill bits with my drill press. The front take down pin holes are a little off straight across. My drill press has a slow setting by adjusting the belts on the pullies however I don't think they adjust slow enough. The titanium dulls the bits up pretty fast. I broke one smaller bit however it was close enough to the top of the hole and it sort of shattered so I was able to get the remains out. I am unable to post photos here as I am borderline retarded and seem to be unable to figure out how to post. |
|
Quoted:
Quoted:
Very cool. Where did you get the cast titanium receiver? I been wanting a ss ar receiver but seemed to have missed the boat on that. 43sec with google: https://www.vbd.com/noc/shop/products_detail.asp?CategoryID=29&ProductID=286 thanx |
|
UTEP, Metalurgical Engineering dept.
call and ask, they are always helpful. Or shoot me an email. I have two UTEP grads on staff. Lark Heat Treating in Houston. Lark Heat Treating.com And NO, this is not an advertisement. I am not selling anything, just offering to help. |
|
quote]Quoted:
I ordered a 1 1/8" drill bit and a 1 3/16"-16 tap for the buffer assembly. When I get the thing done I will take some photos and have someone assist by posting photos here for me.[/quote] That large of a hole is a lot easier if u step it up I would step that up through several sizes |
|
Quoted:
quote]Quoted: I ordered a 1 1/8" drill bit and a 1 3/16"-16 tap for the buffer assembly. When I get the thing done I will take some photos and have someone assist by posting photos here for me. That large of a hole is a lot easier if u step it up I would step that up through several sizes[/quote] The hole is already there and pretty large for the buffer assembly/stock. Basically I am just reaming the hole. I think a tapered bit would have been great for this part. Below is the link to the lower I have. http://www.vbd.com/noc/shop/products_detail.asp?CategoryID=29&ProductID=286 |
| Tried to drill buffer/stock assembly hole with a drill press. Even on the slowest belt setting the bit spins too fast and the titanium chewed up the bit. I guess I will have to order one of the tapered drill bits and try that. I wish I had a milling machine. Future purchase I guess. |
|
Carbide cutters, TiAIN coated
Actually C2 uncoated carbide endmills will work fine. The titanium, friction and heat combination will cause the titanium being cut to adhere to the "Ti"AlN cutting edges of the mill. Now if you were doing a turning/lathe application it would be different. And yes you would be better off with a small milling machine. It can be done but it's a tricky process with a drill press and carbide drills and mills machining titanium. Tapping is a whole different animal. It might have been less costly to have a local machine shop finish it out for you. |
|
Tools you will need:
Heavy duty Morse Taper drill press Drill/Tap control for the drill press (moderates speed of the press for tapping/milling) Morse taper end mill holders Heavy duty morse taper tap drivers Solid carbide or carbide tipped drills C2 5 flute high helix uncoated carbide endmills w/ flats on the shank Spiral Fluted Plug Taps(for through holes) Spiral Fluted Bottom Taps(for blind holes) **Note: Be careful working with the carbide endmills and drills on the drill press. Wear a good thick apron, gloves and use a complete face shield. Solid carbide tooling is designed to be used in CNC machine applications w/ ridgid holding jigs and fixtures.*** |