speed and feed for spade drill

[Guest]

I need to drill 1.4375 hole through some

tubing. the dom tubing is 2.500 O.D. x 1.500 I.D

Im going to use a 1 7/16" tin coated spade drill.

any tips on speed and feeds for this.

thanks

[chris m]

I'm not sure that a spade drill is going to be really happy going into a radiused surface, but if you have experience with it I'll defer to you because I don't.

 

Allied Machine and Engineering's website has feed and speed recommendations for their spade drills here:

 

AMEC technical info

[Guest]

i havent tryed it yet.

im going to spot drill first.

than use the spade.

i was hoping it would be better and faster

than a HSS drill.

Thanks for the imfo above,

helped alot..

[strabe]

I'm with Chris. I think I would try a pocket routine with an endmill. You'll get a pounder hole this way. M2CW.

[fistafury17]

What about a helical circle mill with a centercutting endmill.

[strabe]

I'm not a big fan of milling a hole or rectangular opening without a full pocket routine since the slug can catch and bind between the endmill and side wall of the opening. This can get real ugly real fast. Not that you can't do it. I see people do it all the time. But my experience has been it's better to make chips than slugs. It's a safer but slower way to go.

 

JM2CW

 

Ken

[Thad]

Is there a particular reason why you're using a spade drill and not any one of a variety of insertable drills (Ceratip's Magic Drill, Ingersoll's Quad Bore drills, etc) that are available? Most don't require a spot and can drill straight into an angled surface.

 

Thad

[Die Sinker]

The spade drill will NOT be happy and you won't be happy with the results. Just an old-timer speaking.

[Guest]

im opean to other typs of drills.

i have to drill two holes in each pc.

than im boring them .0015 under 1.500"

so i can press two 1.5" shafts in to tubing.

 

I have 330 pcs to do. so im all ears to what u all have to say.

thanks

[Racerje]

I am with Thad insert drills work great and you can just change insert and keep going don't have to go to drill grinder when it wears down. No spot drill needed either.

[chris m]

Sandvik's Corodrill 880 series are nice, as are Iscar's [can't remember the name] inserted drills. Iscar's are shorter, which I like, and use square inserts which gives you more bang for the buck.

 

Both are expensive, so sit down before you quote them

[Guest]

I was always told insert drills had

to have a flat serface to drill on.

what about the slug in between the walls.

i thought that would give me a problem.

[chris m]

Inserted drills definitely do not need a flat surface, though I think I would drill from the convex side of the tube, index 180, repeat, instead of going thru-and-thru because the inserted drill will not like the corners being in the cut before the center is. There shouldn't be a slug with an inserted drill, though you can get a disk-like piece when drilling through solid. I think the convex shape inside the tube will probably prevent this from forming in your application.

[ReDEyZZ]

quote:

---

Sandvik's Corodrill 880 series are nice

---

+1 They outperform all others I have tried.

 

 

quote:

---

I was always told insert drills had

to have a flat serface to drill on.

---

not really, you just need to slow down the feedrate until you get full dia. , then punch it thru.

[Guest]

Thanks guys

i called a rep, he said it would work

so i got one comming.

learn somthen new all the time..

thanks again