Titanium

[crankshafter]

I can get some Titanium rod (dia. 7/8"x`3' lenght) and some offcuts, dia.3-5". Is it difficult to turn-drill-mill--- . Expensive kind of metall?????????( Can have it for free and btl. of beer)
Do you have any ideas what I can use it for in modelmaking.
regards CS

 

[MadKad]

I only really use titanium due to me making body jewllery, its stronger than steel but lighter.

Now for drilling, just use a standerd HSS drill bit (sharp) and drill at high constent presure, but at low RPM. if you drill fast the bit will burn out as at high speed titanium gets strong.

For lathe and mill just again standerd tools and work slow, it cuts like butter and I love it, I really hate steel as I cut some twice for use and it is just a pain comperd to titanium.

Then after you have done anodize it if you do want to or need any more tips give me a shout.

Or sell it me really cheap as I buy it all the time and only bargens grade 5 up

 

[rake60]

Titanium is a strong alloy that can be used for just about anything.
It won't corrode, it's very stable and if handled properly free maching.

HSS tooling seems to be more effective than carbides for maching it.
It's gummy to cut. Sharp tools are a MUST!
It will also work harden very quickly. You never want to stop the feed
on a running cut and allow the tool to dwell in contact with titanium.
It will create a hard spot that will be a real PIA to get past.

Rick

 

[Circlip]

You can get it cheap if you can gain access to a scrap SR-71 (Take a hacksaw with a new blade fitted)
Regards Ian.

 

[rickharris]

Difficult to impossible to join other than by mechanical means (nuts & bolts or similar) Attractive when anodised, in industry generally cast to shape as this improves strength.

Apparently concord has titanium wash bowls if you can find one that isn't in use. ;0

 

[Tin Falcon]

Difficult to impossible to join other than by mechanical means (nuts & bolts or similar) Attractive when anodised, in industry generally cast to shape as this improves strength.

Hmmm In my experience Ti can readily be welded with the proper equipment ie a good TIG welder For the best weld an inert atmosphere is used. or spot welded. Ti although expensive comes in pretty much the same forms as other common metal ie sheet tube solid rods etc. some of the best bicycle frames are made out of it.
As for models if anyone here decides to buils a model jet engine of the shreckle design or similar ti is great due to its high heat characteristics.
I use to patch the Ti heat shields on jet aircraft on a regular basis.
Tin

 

[bob ward]

There was a lengthy discussion recently at HSM or practicalmachinist re the fire hazard of titanium turnings.

 

[MadKad]

LOl welding titanium I my self wouldnt do, it can have a habit of fireing parts off of titanium and they glow to a very high white and burn out very slowly, the same can come from grinding, it often happens when I grind titanium and the brightness can really blind you. The welding you show there, did you do that? also did you weld with titanium to titanium?


Bob that would be an intresting read (please could you show me the link), I have turned titanium since I started on a lathe and have found no problems, my parts doing even get hot.

 

[Tin Falcon]

MK:
yes that is one of my welds from Tech school. One of many, I was able to keep a few. I would not hesitate to weld Ti at home if I had a Tig.
two pieces of sheet ti held in a jig with backup gas and Ti filler rod . open bench, not inert cabinet.
Call me crazy by also have welded Magnesium. That I would not likely do in a home shop too many nasty fumes.
I personally have never accidentally lit up any titanium or magnesium nor have I seen a co worker do it. Not saying it can not happen.
Tin

 

[zeusrekning]

My dad used to setup and run a CNC swiss screw machine.This machine used a cutting oil bath instead of coolant. I can't remember the number of oil nozzles but there were many. He was making orthapedic bolts out of titanium one night when the oil lit up. It took him a sec to realize what it was b/c the inside lights put off an orange to amber glow shining through the oil normally.

 

[MadKad]

Tin I didnt see that you had said you used a tig in your first post, I was told that this is the only way to weld titanium, alot of places will only rivit it to other titanium due to the welding, I know it has a high melting point.

My dad used to setup and run a CNC swiss screw machine.This machine used a cutting oil bath instead of coolant. I can't remember the number of oil nozzles but there were many. He was making orthapedic bolts out of titanium one night when the oil lit up. It took him a sec to realize what it was b/c the inside lights put off an orange to amber glow shining through the oil normally.

I have never used cooling on titanium as you shouldnt be cutting it at high speeds to even need cooling, higher the speed when cutting it becomes very hard to cut.

I would say if they made full titanium drill bits for cutting at high speed on steel they would last a long time but not them titanium couted lol

 

[macona]

Titanium does not become harder to cut at high speeds. It seems that way but its not quite right.

Titanium has terrible thermal conductivity. So the heat of cutting all goes through the cutting tool. When this happens the edge breaks down quickly and then you start rubbing. The rubbing work hardens the material almost instantly. Things start snowballing from here.

So when turning titanium keep your tools sharp and use coolant of some kind, wether it be air, mist or full flood. Especially if you are using HSS. If you are using carbide you can run three to four times faster.

And dont stop and let the tool rub! Heavy feeds can help tool life as well.

Titanium is easy to anodize. I build a variable voltage power supply, 0-150v DC, 3 amps, using an old variac, bridge rectifier, electrolytic cap, and a panel meter. Use a solution of TSP and some water to make electrolyte. Use a piece of your turnings as a cathode in the water (Negative) and use a hook made from titanium to hold your work. Start at low voltage and increase. The anodizing builds a layer of Titanium Oxide on the surface. The higher the voltage the thicker the layer and that effects the color reflected.

I have posted this pic before, but here are a couple rings I made out of Ti.

 

[MadKad]

macona: what RPM do you run at when cutting titanium then?

thanks

 

[macona]

On 7/8" dia 6Al4V with HSS, no coolant around 300 to 400 rpm, carbide around 1000 to 1200 RPM. Past that you need coolant.

 

[MadKad]

On 7/8" dia 6Al4V with HSS, no coolant around 300 to 400 rpm, carbide around 1000 to 1200 RPM. Past that you need coolant.

Thanks

Thats is the same as I do, so its not really fast as you go higher than this for steel. I have never got so fast that I need coolant as at this time I have never needed to go that fast I cant think of any reason why higher speeds would be needed?