New Tools

[VertigoCycles]

I guess I'm showing off a little since it's not Friday. I've been unhappy with my bendy setup lately and after tossing a set of seat stays in the "to be used later on a much smaller bike" bin, I took the day off from "work" and started building a new bender. It's not cost effective, but I get to learn by doing since I don't know much about machining. I didn't even draft a design, which is completely out of type for me. More to work through as I build the rest over the next few days, but it's been a blast so far. I can't imagine making something like this out of steel.

[Zimmermanbicycle]

Looks great!
I'm thinking of taking a day off to make a new fork blade bender in a 6" radius for that classic Alex Singeresque bend.
-Eric

[Dazza]

I guess I'm showing off a little since it's not Friday. I've been unhappy with my bendy setup lately and after tossing a set of seat stays in the "to be used later on a much smaller bike" bin, I took the day off from "work" and started building a new bender. It's not cost effective, but I get to learn by doing since I don't know much about machining. I didn't even draft a design, which is completely out of type for me. More to work through as I build the rest over the next few days, but it's been a blast so far. I can't imagine making something like this out of steel.

You just have got to do this some times
drop every thing
and make it

[cardinal]

Sean, looks great. You know a lot more about machining than you let on. It's impressive to see the way you used your rotary table for this thing. Nice work.

[VertigoCycles]

Sean, looks great. You know a lot more about machining than you let on. It's impressive to see the way you used your rotary table for this thing. Nice work.

I know just enough to get myself into some serious trouble.

[Archibald]

It's all about rigidity of set up and speeds & feeds. With 6061 and regular 1/2" hss 4-flute end mill taking a .25" DOC and a full width slot (.5") you'd want to run about 300-350 SFM so you're looking at 2600 rpm @ 30-ipm with a .003 ipt chip load. It goes up from there with coatings and carbide. With ball end mills, it works a little different since you're working depths of cut on the bottom of the ball so you want to reduce your chip load for the sfm. With the ball, always run your roughing cuts short on depth and then finish with .01" final DOC. Also offset the X a thou or three on the return path so you're climb milling both sides of the slot and it will give you a much better finish.




Conventional milling with .75" Hanita Javelin 3-flute TiCN @ 6,000 RPM x 84ipm on .150" radial engagement and 1" depth of cut in Mic6.