Drill bit for drilling holes in bars?

[BobL]

I agree with Zippymbr about using a smaller bit first.

I have drilled about 30 holes in a number of different types of bars (just about all my bars have holes thru the middle of the nose) and have tried just about everything in the way of drill bits. Carbide and carbide tipped bits work (even concrete hammer drill bits) well but I prefer the Cobalt bits because I can resharpen them. I have 3 bits I use for bar drilling, 1/8, 1/4 and 5/16". I start with the 1/8" on about 750-1000 rpm in a drill press with lots of coolant/lube and moderate to high pressure. Then I use the bigger bit on ~250 rpm also with lots of coolant/lube. The pressure needs to be positive to maintain continuous cutting, and don't let the drill chatter in the hole otherwise it further work hardens the steel. Using the bigger bit without the pilot hole works but it's much harder to start and maintain the cutting action and ends up dulling the point after just one or two holes.

 

[nicklt040]

why do you drill holes in the bar. I didnt get the answer wiggles gave

 

[BobL]

why do you drill holes in the bar. I didnt get the answer wiggles gave

I do it to fix the bars to my CS mills.

 

[Justsaws]

Anyone suggest a specific drill bit (and source) for drilling 1/4 inch holes in chainsaw bars?

Mine have given up the ghost and I need to drill some more holes. I want good quality, but I don't need a full set. The bits, screw extractors, etc I've tried in the past from HD, Lowes etc were pretty poor quality.

I didn't look what I had the DP set to, but maybe it was a little too fast.

I read somewhere I should drill as slow as possible with lots of pressure until the end. Sound right?

I have no real metal working background, so I thought I'd pick people's brains a little.

Drill press, lots of coolant, slow-med speed, watch chip production rate for amount of pressure to apply and a sharp drill bit. The last 3 GB bars recieved 2 3/8" holes each from one generic Stanely brand twist bit and it is still good to go.

Coolant, speed, pressure, sharp bit. Center punch the hole. Flood the bit area with coolant.

 

[Justsaws]

I do it to fix the bars to my CS mills.

Yep. Mills or other guides.

 

[husq2100]

They seem a bit too good to be true, but I am going to keep my eye out for them.

Thanks.

I tried resharpending my HS bit on my bench grinder which I have luck with sometimes, but I typically get too thin an included angle on the edge and the bit dulls too fast.

I thought the same thing for a few years, then took a punt. They work very well. They are made in Germany. Last time I used them was with a mate and we drilled 16mm (5/8) in Bisalloy.

Other than that I would recommend cobolt, with cutting fluid.

 

[7oaks]

why do you drill holes in the bar. I didnt get the answer wiggles gave

For using different "mount" bars on saws they weren't designed to work on. You drill out the bolt slot, adjustment hole and the oil holes to match the pattern of the bar you want it to match.

 

[B_Turner]

http://www.artu.com/drillbits.htm

They can be bought all over the country. . . Watch the video of the bit drilling through a file.

I bought one of these artu drill bits today, marked 1/4 and in 1/4 package.

I didn't notice the first hole, but turns out it is quite a bit oversize. I first noticed when I realized it would not go into a 1/4 inch bushing I was using for a locator.

I wasn't real happy about that. What size do I need to make a 1/4 inch hole? (Has to do with the material they add at the tip.)

Finished up with a cobolt real 1/4 inch bit.

Also weird how they claim that to drill hardened steel 2000 rpm is a minimum. Hmmmmmm

 

[Metals406]

I bought one of these artu drill bits today, marked 1/4 and in 1/4 package.

I didn't notice the first hole, but turns out it is quite a bit oversize. I first noticed when I realized it would not go into a 1/4 inch bushing I was using for a locator.

I wasn't real happy about that. What size do I need to make a 1/4 inch hole? (Has to do with the material they add at the tip.)

Finished up with a cobolt real 1/4 inch bit.

Also weird how they claim that to drill hardened steel 2000 rpm is a minimum. Hmmmmmm

Call the company and voice your concerns. . . Those bits aren't cheap.

As far as the higher RPM, that's probably how they're designed. . . I'm a dealer for Cermet tipped blades that you have to run at 3,500 (ish) -- or they don't work.

If you're unhappy with it, I'm sure the company will make it right.

 

[B_Turner]

Call the company and voice your concerns. . . Those bits aren't cheap.

As far as the higher RPM, that's probably how they're designed. . . I'm a dealer for Cermet tipped blades that you have to run at 3,500 (ish) -- or they don't work.

If you're unhappy with it, I'm sure the company will make it right.

It was about $8.50.

I probably will just toss it in a drawer, but l sure was expecting a 1/4 inch bit to be designed to drill a 1/4 hole.

I did run a fair bit of speed on the DP when I drilled the hole. Then I realized about the oversized issue so I didn't get a chance to get a good feel for it on more holes.

Naturally I slowed down the DP pretty slow when I drilled the other holes with the cobolt bit.

One other thing I didn't appreciate about the artu packaging is that it says artu USA in big letters on the packaging, but if you read close it was manufactured in China.

 

[Metals406]

It was about $8.50.

I probably will just toss it in a drawer, but l sure was expecting a 1/4 inch bit to be designed to drill a 1/4 hole.

I did run a fair bit of speed on the DP when I drilled the hole. Then I realized about the oversized issue so I didn't get a chance to get a good feel for it on more holes.

Naturally I slowed down the DP pretty slow when I drilled the other holes with the cobolt bit.

One other thing I didn't appreciate about the artu packaging is that it says artu USA in big letters on the packaging, but if you read close it was manufactured in China.

Hmmmm, that's a big no-no for me too. The gal on the phone was bragging that their stuff was USA.

I'm glad, and sorry, you bought one of their bits. . . I intended to buy some at a later date -- now I'm not so sure.

Theirs always the old standby trick of heating a hss bit tip past non-magnetic and dipping the end in fresh urine. Makes the bit hard as all get-out, but very brittle like carbide.

 

[husq2100]

Dont know whats going on in the Good ol USA, but all the Artu bits I have used here have been sized on the tips and made in Germany.

yes the tips are bigger like a masonary bit, but all have been the correct size. Sounds like Artu USA needs to sort there #### out.

Yes the RPM should be higher for the material that they are made from.

 

[B_Turner]

Dont know whats going on in the Good ol USA, but all the Artu bits I have used here have been sized on the tips and made in Germany.

yes the tips are bigger like a masonary bit, but all have been the correct size. Sounds like Artu USA needs to sort there #### out.

Yes the RPM should be higher for the material that they are made from.

Maybe artu uses their brand name to also market cheaper Chinese drill bits to the general public. I bought mine at a Ace Hardware because I was having trouble finding one and I heard they had them.


Leveraging their brand name for some additonal revenue stream.

It just didn't occur to me the bit would be over sized because I have never seen that before.

They had more sizes at the store. Maybe they need a chart to look up what size actually makes a 1/4 inch hole.

 

[Arky217]

No problem

No problem; just go to Ace hardware and get one of those bits for drilling bathroom tile. Works for me.

 

[Brian VT]

I have a buddy with access to CNC laser and water jet machines. That might be my best bet instead of drilling ?

 

[Justsaws]

I have a buddy with access to CNC laser and water jet machines. That might be my best bet instead of drilling ?

If you have access to a variable or slow speed drill press and the ability to flood the bit tip area with coolant it is not a difficult thing to do at all.

You can do it with a hand held drill as long as you are patient and use the appropriate techniques.

Center punch hole(deep punch), sharp bit, slow-med speed, pressure and lots and lots of coolant flooding the tip of the bit.

I just drilled an Oregon PowerMatch Plus bar for an auxiliary oil-er(drilled tip) and mill mounts with the 3/16" and 3/8" bits from a $10.00 set of Black and Decker cheapys. Worked fine and the bits will drill more bars before they are done.

 

[Grande Dog]

Howdy,
We've drilled a bar or two. The biggest thing is the rpm. It has to be way slow to do a good job. We took our drill press and added another jack shaft with a step pulley. It ended up having about 45 RPM in low. I used to stack and drill 10 bars at a time with this method. We used the masonry bits. We had a diamond wheel on a pro grinder so I could put a real nice edge on the carbide. Because of hardening, the closer you get to the edge of the bar the harder they are to drill.
Regards
Gregg

 

[B_Turner]

Howdy,
We've drilled a bar or two. The biggest thing is the rpm. It has to be way slow to do a good job. We took our drill press and added another jack shaft with a step pulley. It ended up having about 45 RPM in low. I used to stack and drill 10 bars at a time with this method. We used the masonry bits. We had a diamond wheel on a pro grinder so I could put a real nice edge on the carbide. Because of hardening, the closer you get to the edge of the bar the harder they are to drill.
Regards
Gregg

Never thought of stacking a couple bars at once, good idea. And the bar below would provide great backing I would think.

Did you drill in one pass or did you back out the bit as you went (to clear shavings or lube it etc)?

 

[B_Turner]

Thought I'd followup on the "1/4" artu drill bit I bought.

First I switched over to a cobalt twist bit and it worked well (bunches of holes) because the artu was oversized.

I did try the artu again on a bar a couple times when it didn't really matter if the hole was oversized.

I really hated it, as it didn't cut very fast (and got smoking hot). I know it's supposed to get hot (runs real fast) but bottom line it did took considerably longer than my hss and cobalt regular twist bits and did not make a clean hole like my regular bits did..

Maybe since it is the chinese version it is not the same as what you guys have that like it so much.

Also I sent an email to artu about the oversizedness and never heard back.

Big thumbs down in my opinion.

 

[pioneerguy600]

Thought I'd followup on the "1/4" artu drill bit I bought.

First I switched over to a cobalt twist bit and it worked well (bunches of holes) because the artu was oversized.

I did try the artu again on a bar a couple times when it didn't really matter if the hole was oversized.

I really hated it, as it didn't cut very fast (and got smoking hot). I know it's supposed to get hot (runs real fast) but bottom line it did took considerably longer than my hss and cobalt regular twist bits and did not make a clean hole like my regular bits did..

Maybe since it is the chinese version it is not the same as what you guys have that like it so much.

Also I sent an email to artu about the oversizedness and never heard back.

Big thumbs down in my opinion.

Thanks for that heads up on them bits, I was entertaining the idea of getting some of them but now don`t think I will bother. I always have used colbalt bits in leaf spring and chainsaw bars plus any other hardened steel I have to drill and had good results. Anyone use Whitworth or Butterfield bits?
Pioneerguy600