S |
M |
T |
W |
T |
F |
S |
|
|
|
|
|
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
13
|
14
|
15
|
16
|
17
|
18
|
19
|
20
|
21
|
22
|
23
|
24
|
25
|
26
|
27
|
28
|
29
|
30
|
|
|
|
|
|
|
|
1 members (Birdog),
137
guests, and
2
robots. |
Key:
Admin,
Global Mod,
Mod
|
|
Forums10
Topics38,600
Posts546,885
Members14,426
|
Most Online1,344 Apr 29th, 2024
|
|
|
Joined: Feb 2004
Posts: 13,880 Likes: 16
Sidelock
|
Sidelock
Joined: Feb 2004
Posts: 13,880 Likes: 16 |
Marc, Any radius is possible. Simply use a convex side milling cutter (horizontal mill cutter) and a horizontal mill or a stub arbor in a vertical mill and tip the barrels up. By using a cutter of just the width needed to cover the widest point of the rib, you can then grind any radius on the cutter desired and still not hit the barrels. I know not everyone has the equipment, but I'm just stating what is possible if you're willing to pursue it.
|
|
|
|
Joined: Feb 2004
Posts: 13,880 Likes: 16
Sidelock
|
Sidelock
Joined: Feb 2004
Posts: 13,880 Likes: 16 |
I almost forgot, tipping the head on a verticle mill with a square cornered cutter will also allow you to cut a larger radius with a smaller diameter cutter. You can only use a certain portion for producing a true radius (or very close to it) because it forms an elipse when the head is tilted.
So, for a test of this, tip the head of the mill with a, say, 3/4" endmill in it about 30 degrees. Then cut test part. You'll get a pretty large radius in about the middle 1/2" and then the raduis tightens up quickly around the edges. Somewhere you can find a formula for this process that will produce the desire radius. I've used it many times in the past (20 or more yrs ago).
If you use a ball endmill to cut the rib, tilt the head similarly to above such that the center of the endmill doesn't cut a little swirl down the middle of the rib.
|
|
|
|
Joined: Jan 2002
Posts: 461
Member
|
Member
Joined: Jan 2002
Posts: 461 |
Chuck Now you talking. Tipping the head to the side on the milling machine is the way to go. If you have a Bridgeport type Mill. Also drilling a hole midway down the rib you can install a small sight that will look like it belong there Casey
|
|
|
|
Joined: Feb 2004
Posts: 13,880 Likes: 16
Sidelock
|
Sidelock
Joined: Feb 2004
Posts: 13,880 Likes: 16 |
Casey, I recall cutting something like a 24" radius on a Bridgeport (glorified drillpress) with a large (10" ish?) flycutter tipped at an angle.
|
|
|
|
Joined: Jan 2002
Posts: 674
Sidelock
|
OP
Sidelock
Joined: Jan 2002
Posts: 674 |
Would you cut it with the head at an angle from the begininng, or would you mill the raised rib down close to the barrels with a small diameter end mill and then swap to a larger diameter cutter with the head kicked up?
skunk out
|
|
|
|
Joined: Feb 2004
Posts: 13,880 Likes: 16
Sidelock
|
Sidelock
Joined: Feb 2004
Posts: 13,880 Likes: 16 |
I'd tip the head and cut a practice piece and use an optical comparator or other (string or trammel cut template for a radius gauge) method to check the radius and then set the barrels and cut them with some shallow cuts and keep going down to the depth of choice.
|
|
|
|
Joined: Jan 2002
Posts: 749 Likes: 16
Sidelock
|
Sidelock
Joined: Jan 2002
Posts: 749 Likes: 16 |
Marc, this is just a thought, if the rib has a center bead, just remove the center bead and see if the rib is hollow. You should be able to see just about how thick the rib is at near the center point.
I'm NOT a metalsmith as you are aware so this is just a guess on my part.
Doug Mann
|
|
|
|
Joined: Jan 2002
Posts: 461
Member
|
Member
Joined: Jan 2002
Posts: 461 |
Marc With this setup you make a final cut .002/.003 deep and very good feed rate to make the rib finished with a nice tool marks Casey
|
|
|
|
Joined: Jan 2002
Posts: 674
Sidelock
|
OP
Sidelock
Joined: Jan 2002
Posts: 674 |
Doug-
no center bead, but great idea though!
Casey-
What feed rate would you reccomend? I plan on using just a plain ol' 4 flute carbide end mill. Well, of course I coule use HSS as well.
skunk out
|
|
|
|
Joined: Jan 2002
Posts: 3,642 Likes: 1
Sidelock
|
Sidelock
Joined: Jan 2002
Posts: 3,642 Likes: 1 |
Marc, Just to give you an idea of a light set up, here are pictures of my Manufrance Ideal's barrels: JC
"...it is always advisable to perceive clearly our ignorance."ť Charles Darwin
|
|
|
|
|