Helix Bore?

[Mcam Nut]

I am trying to basically trepan 4 large holes with a endmill, and to save time from using a pocket tool path, I want to just use a helix bore pass. However at the end of the helix bore cycle ot wants to feed to the center of the bore before retracting. Is there a switch or somthing to keep it from going to center before retracting?

 

Thanks

[jeff]

Uncheck "Start at center"?

 

I never use Helix Bore, out of habit I've always used contour ramp, easier to control the start/end points with the lead in/out that way.

[Guest]

Contour Ramp

[gcode]

Like John said.. Contour/Ramp and make sure

you have no lead out move

[Mcam Nut]

I never tried contour ramp, works great

[K2csq7]

I always use contour ramp, works great, i feel like i can control everything i need to. Can someone tell me why i would ever use helix bore?

[Colin Gilchrist]

Because sometimes you don't want your tool retracting at rapid up the wall.

 

You also get some controls to slow the feed rate down as you reach the bottom of the hole.

 

Plus you can define a separate rough and finish pitch value, and separate rough and finish speeds and feeds.

 

For Hole cutting, Helix bore is my go-to toolpath.

 

Ramp contour works great because you can drive a chain of any shape, which you can't do with helix bore...

[K2csq7]

Thanks Colin, I like the idea of being able to have separate pitch values & feed rates.

[kunfuzed]

How often does anybody finish a hole with a helix bore? Doesn't it usually come out bell-mouthed? I prefer contour ramp for the option of steping over for a multi pass finish cut. I've learned you can also accomplish this with circle mill and roughing. The circle paths are nice if you have a lot of holes to select.

[heavychevy2155]

I also use circle mill for most of my milled holes. It has all the control I need most of the time.

[Jayson Kramer]

I am with Colin and Kunfuzed I do use it for a finish to leaves a mice finish on deep holes.

[Grievous]

Just a sugestion. You can change post so you can have the codes like this:

 

M01

G54G90G00X0.Y4.5A0.B0.S1500M03

G43H2D2Z1.M08

Z.05

G01Z0.F9.

G41X.2618

#10=0(COUNTER RESET)

WHILE[#10LT22.]DO1(LOOP START)

G03G91Z-.04I-.2618J0.

#10=#10+1.(COUNTER INCREMENT)

END1(LOOP END AT Z-.88)

G90I-.2618J0.

G01G40X0.

G00Z1.

The operator can have control of pitch after posting. I can share the routine if you guys want.

Or in mighty Sinumeric can be like this:

N98 G54 D1

N99 CYCLE800(1,"DMG",10,27,,,,,,,,,,1)

;**********************

MSG("C/BORES FOR 1/2 SHCS")

N100 S6000 M3

N101 G0 X18. Y0.

N102 Z5. M8

N103 Z.145

N104 G1 Z.095 F40.

N105 G41 X18.175

N106 G3 X18.175 Y0. Z-.625 I-.175 J0. TURN=18.

N107 X18.175 Y0. I-.175 J0.

N108 G1 G40 X18.

N109 G0 Z5.........

[kunfuzed]

quote:

---

I am with Colin and Kunfuzed I do use it for a finish to leaves a mice finish on deep holes.

---

Actually I don't finish with this, I only rough. Like I asked in my previous post, doesn't this make your holes come out bell-mouthed? Especially deep ones?

[Colin Gilchrist]

My holes never come out bell-mouthed. I use Extended Carbide cutters (short flutes, solid relieved shank). With the controls in this toolpath I go as deep as 6:1 Depth to Diameter ratio. Any deeper than that and you really need to look at a different technique like drilling and reaming.

 

I typically hold +-.0002 on diameter (under 2:1 D2D) (but you have to measure the tool accurately first and have low run out). The only drawback with the helix bore is that you don't have cutter comp. If you need to comp the tool, then use the Contour Ramp toolpath...

[Cad-Camr]

The ramping functions are nice to use here and there but I would drill a hole slightly larger than the End Mill at the start point, drop the tool in and 2d contour for rough and finish with another tool. Ramp tool paths arnt very efficient.My 2c

[kunfuzed]

quote:

---

My holes never come out bell-mouthed. I use Extended Carbide cutters (short flutes, solid relieved shank). With the controls in this toolpath I go as deep as 6:1 Depth to Diameter ratio.

---

Yeah, I can see that. I was going to ask what kind of cutter. What pitch do you usually finish with?

 

quote:

---

The only drawback with the helix bore is that you don't have cutter comp.

---

Wut?

 

I think you should check again.

[Grievous]

quote:

--------------------------------------------------------------------------------

The only drawback with the helix bore is that you don't have cutter comp.

--------------------------------------------------------------------------------

 

Ya.., like kunfuzed said : Check again. There is cutter comp.

[Dave.L]

quote:

---

The ramping functions are nice to use here and there but I would drill a hole slightly larger than the End Mill at the start point, drop the tool in and 2d contour for rough and finish with another tool. Ramp tool paths arnt very efficient.My 2c

---

Depending on what you are doing, Ramping can be VERY efficient. I use this to do holes quite often and it’s a lot faster than tool changing thru multiple tools.

[jeff]

quote:

---

Depending on what you are doing, Ramping can be VERY efficient. I use this to do holes quite often

---

Same here.

You can remove quite a bit of stock very quickly by ramping a 1-1/2" facemill either inside a bore, or around a form.

Of course it's situational just like everything else.