MotoFiaccone Bob--Feb 2011 update
- Thread starter chrisf
- Start date
It gets worse....It has to me immaculately clean--much cleaner than stainless or even aluminum. And it has to be 100% purge welded. I purge weld all my stuff, but I've never tried it with 25 pie cuts before. And of course, the fit-up has to be perfect.
The nice thing is that Ti welds much easier than Al or stainless, at least to me. Mild steel, believe it or not, is the hardest to weld.
--Chris
The nice thing is that Ti welds much easier than Al or stainless, at least to me. Mild steel, believe it or not, is the hardest to weld.
--Chris
Swapmeet Louie
Put some metal in yer eye....
Swagger said:
need a side kick? haha...
I'll dress up like fuck'n Robin! and work!
The Red Wonder
Been Around the Block
Well here they are, those Ti bits that needed machining. These took me the better part of 8 hours, mostly for my lack of knowledge of working with the material. I had been told "slow speeds, fast feeds"...but I didn't realize how slow that you really need to go to cut this stuff cleanly. Chris gave me a fat chunk of Titanium to cut these parts out of, so it was a little tricky trying to figure out where everything would come from:
This is how I ended up doing it (the end caps are shown backwards here:
I first started by cutting a sliver off the top to get the flange....this part proved to take the longest when I thought it would go the quickest. The horizontal band saw chopped through it quite nicely but left the sliver a little fatter than needed. I had to mount it up in the mill and fly cut .050" off the top. It is still a little thicker than the piece it is replacing, but with out a carbide cutter, the material just wasn't coming off.
I center punched the two holes, drew a line connecting them, bisected it and found the center of the main hole. Put the piece back in the mill, drilled the holes and then set on making the large center hole...this took way long
I worked up from small drill bit until 1/2". Then I moved in to end mills to plunge, .75" - 1". These weren't happy. The tools weren't carbide, simply high speed steel and were dulled pretty quickly. After re-sharpening, I found that I had work hardened the last .050" that need to come out of the bottom so I had to get the dremel out and cut it all away. From there I went to a boring bar with a carbide tip that worked flawlessly, I also had to slow the speed down to about 100 RPM, from ~190. This was key. Finished that piece and moved on to the round bits.
I contracted the band saw to cut out the rectangle then chucked it up in the lathe, as close to center as possible:
This is was a slow process of turning a square into a cylinder, but it can be done:
Once I had the OD set for the largest piece, I set on boring out the inside:
Then I cut each piece off with the parting tool and voila! All done with the Ti. In all, these parts consumed about 7 hours with the last hour going to the 4 Stainless Steel Headlight holder pieces.
And the finished product:
(SS pieces in the back)
It was neat to work with a new material, but I don't plan on cutting any more Ti anytime soon...haha!
This is how I ended up doing it (the end caps are shown backwards here:
I first started by cutting a sliver off the top to get the flange....this part proved to take the longest when I thought it would go the quickest. The horizontal band saw chopped through it quite nicely but left the sliver a little fatter than needed. I had to mount it up in the mill and fly cut .050" off the top. It is still a little thicker than the piece it is replacing, but with out a carbide cutter, the material just wasn't coming off.
I center punched the two holes, drew a line connecting them, bisected it and found the center of the main hole. Put the piece back in the mill, drilled the holes and then set on making the large center hole...this took way long
I worked up from small drill bit until 1/2". Then I moved in to end mills to plunge, .75" - 1". These weren't happy. The tools weren't carbide, simply high speed steel and were dulled pretty quickly. After re-sharpening, I found that I had work hardened the last .050" that need to come out of the bottom so I had to get the dremel out and cut it all away. From there I went to a boring bar with a carbide tip that worked flawlessly, I also had to slow the speed down to about 100 RPM, from ~190. This was key. Finished that piece and moved on to the round bits.
I contracted the band saw to cut out the rectangle then chucked it up in the lathe, as close to center as possible:
This is was a slow process of turning a square into a cylinder, but it can be done:
Once I had the OD set for the largest piece, I set on boring out the inside:
Then I cut each piece off with the parting tool and voila! All done with the Ti. In all, these parts consumed about 7 hours with the last hour going to the 4 Stainless Steel Headlight holder pieces.
And the finished product:
(SS pieces in the back)
It was neat to work with a new material, but I don't plan on cutting any more Ti anytime soon...haha!
Wow!! Corey did an amazing job! 8 hours worth of machining is insane. I knew Ti was a bitch to machine, but had no idea it was that bad! Corey: Thanks mate. I owe you!
OK gents, what you're looking at is the bit that gets inserted into the head, as well as the flange that bolts it together. The other round pieces are end caps for a full Ti silencer I'm building. The primary Ti tube is going to be 1"OD. The silencer is 1.5" ID, so it won't do a lot of silencing, but it will help. The silencer will be re-packable, which is nice. I also have a clever idea on how to finish that off, but that's a post for another day.
The final stainless bits are for the headlight mount. Rather than just use a normal headlight mount, what I did was bend a piece of 3/8" stainless rod in a 9" diameter (that was a bitch BTW). Course weave stainless mesh is welded onto that, which I've done but not taken photos. It looks really rough and tough. Anyway, the stainless mesh ring will sit 1' infront of the headlight to keep stones from breaking the glass. What stones? wWho knows, but I wanted to try it.
Back tot he machined bits, those will bolt to the headlight....hmmm...it's hard to explain. Maybe I'll fire up the TIG torch this weekend and try to finish it out. Between the stainless mesh headlight and the Ti exhaust, this little dirtbike is going to kick ass!.
--Chris
OK gents, what you're looking at is the bit that gets inserted into the head, as well as the flange that bolts it together. The other round pieces are end caps for a full Ti silencer I'm building. The primary Ti tube is going to be 1"OD. The silencer is 1.5" ID, so it won't do a lot of silencing, but it will help. The silencer will be re-packable, which is nice. I also have a clever idea on how to finish that off, but that's a post for another day.
The final stainless bits are for the headlight mount. Rather than just use a normal headlight mount, what I did was bend a piece of 3/8" stainless rod in a 9" diameter (that was a bitch BTW). Course weave stainless mesh is welded onto that, which I've done but not taken photos. It looks really rough and tough. Anyway, the stainless mesh ring will sit 1' infront of the headlight to keep stones from breaking the glass. What stones? wWho knows, but I wanted to try it.
Back tot he machined bits, those will bolt to the headlight....hmmm...it's hard to explain. Maybe I'll fire up the TIG torch this weekend and try to finish it out. Between the stainless mesh headlight and the Ti exhaust, this little dirtbike is going to kick ass!.
--Chris
The Red Wonder
Been Around the Block
motofiaccone said:
Yea....we'll talk about this later! HA!
I forgot to mention the coolest part about machining the Ti was beltsanding it. Sparks from steel are a yellow/ orange. The sparks from the titanium were bright white! Almost like burning magnesium, it was sweet. But yea, it is suuuuper tough/ strong metal!
troybilt said:
No. Well, sorta. I can do it a Kit's shop, but he just had a baby yesterday. I'm hoping someone with a bandsaw and some skill can help me out. Once I get the cuts, the exhaust will come together quickly. But like Corey explained, it's a bitch to cut.
-Chris
Corey is knocking the job out for me, which is a relief. This lets me focus on building the stuff instead of cutting it. He did amazing work on machining the other parts, so I have no doubt I made the right decision by having him cut it. He has a massive amount of tools available to him, including a bandsaw with coolant. Nice!
I hope to ship out tomorrow.
--Chris
I hope to ship out tomorrow.
--Chris
brethren22
New Member
motofiaccone said:
are you talking about pipe weld purging? using a fully sealed chamber to ensure there's no oxygen present? or purging with the inert gas from your TIG to try and protect the weld from exposure to oxygen before and after welding? those brown rings you see are a result of some oxygen being present during welding but don't necessarily present a major issue. a true purge welded pipe will result in no visible oxidisation. tough to achieve though, particularly with Ti
anyway, i was just curious as to what approach you are taking. i'm guessing the latter will suffice but the former would be pretty cool to see some shots of! good luck with it, it's cool to see someone working with some exotic metals
