drilling holes

[tubewelder87]

i would say that everybody on here has the right idea. but it think that the main problem with your situation was the hole you made with the welder. Really what you did by doing that was make a harden piece inside of that piece of steel. it is called martinsite. It makes a very hard peice of steel bc of the way you heat it so quickly with the welding rod. I have a very cheap set of drill bits and always drill all of my holes. I think that unless you are real good it is hard to blow a accurate hole. with the cheapos you will have to sharpen more often and if you dont know how that can cause some real problems to. You can ruin a good bit just as fast as cheap one if you over heat it!! just my two cents worth!

 

[jayste]

While bed frame material is hard on drill bits my guess is that your method of making a pilot hole is your problem as well. I'm going to say that no pilot hole is better that one made with a welding rod. Making hard material even harder is a problem but the fact that the pilot hole you're making is not round as is an issue as well. A pilot hole also needs to be concentric with what you're using to follow it up with. A drill bit should make a round hole so start with a round hole. You're probably chipping away you're cutting edge on your drill bit due to the pilot hole. Like others have mentioned, good quality high speed drills are what most folks will need and cutting oil and the right RPM's will help. As Dave said you might have to step up to cobalt simply because you're drilling into some hard material but skip the pilot hole if you do. Let us know how it goes.:thumbsup:

 

[FarmerGene]

It's also possible that poking the hole with the welder might have done something to the metal's temper that made it harder to drill.

When you burn through a peice of metal the heat will work harden the steel and make it harder to drill.

 

[dan_d]

Thanks folks,
It didn't occur to me that the pilot 'hole' might have been the source of my troubles... I'll test out a non-welded peice tonight to see how that goes... assuming i can find a non-worn out bit!

As for the drillbit speed, how do I know what is fast/slow enough for the bit & material? is there some guidelines somewhere on where to start?

I didn't have any oil but I did use WD40, which seemed to help just a wee tiny bit, but i'll keep an eye out for the proper stuff

sal64, found the bits on that site, thanks! what's the difference between "Bright" finish on the ones you mention and these ones (MSC Item Detail) with a "surface treated" finish?


Thanks again for all the advice!
Dan

 

[flusher]

Thanks folks,
It didn't occur to me that the pilot 'hole' might have been the source of my troubles... I'll test out a non-welded peice tonight to see how that goes... assuming i can find a non-worn out bit!

As for the drillbit speed, how do I know what is fast/slow enough for the bit & material? is there some guidelines somewhere on where to start?

I didn't have any oil but I did use WD40, which seemed to help just a wee tiny bit, but i'll keep an eye out for the proper stuff

sal64, found the bits on that site, thanks! what's the difference between "Bright" finish on the ones you mention and these ones (MSC Item Detail) with a "surface treated" finish?


Thanks again for all the advice!
Dan

WD-40? Not the preferred fluid for your job.

Go the the plumbing dept at Home Depot or Lowe's and get a quart of cutting oil that is used for pipe threading. It works fine with twist drills.

 

[dan_d]

WD-40? Not the preferred fluid for your job.

Go the the plumbing dept at Home Depot or Lowe's and get a quart of cutting oil that is used for pipe threading. It works fine with twist drills.

Sounds like a plan. Thanks! :thumbsup:

 

[Brad_Blazer]

One more tip when you are drilling steel you need enough pressure on the bit to continually produce chips or better yet a continuous curl of shaved metal. If the pressure is too low or the speed is too high and the bit just rubs on the bottom of the hole the bit will instantly dull itself.

 

[easygo]

Also if you are using a hand held drill instead of a drill press ease the pressure as it gets through the material. (I need a drill press.) Especially as the bit diameter increases. Otherwise it might break through some and gets caught on the material that has not been drilled away yet. It is an excellent way to create holes that are just about impossible to finish without breaking the bit. I'm a master at that. I mean breaking large bits just as they punch through.
Any advice on that?

 

[dan_d]

hmmm... yeah i guess i was definitely going too fast then! :confused3:

live and learn i guess!

 

[jayste]

As for the drillbit speed, how do I know what is fast/slow enough for the bit & material? is there some guidelines somewhere on where to start?

I didn't have any oil but I did use WD40, which seemed to help just a wee tiny bit, but i'll keep an eye out for the proper stuff

Dan, unfortunately there's not a real good way to tell you about feed and speed on your hand drill. When I do it with a hand drill it's kind of by feel. Remember that smaller bits need faster speed and larger bits need slower. As far as feed (pressure or push) goes push it hard enough to get a short chip and not a "stringer" chip. As others have mentioned, you might want to get some cutting oil instead of WD-40. Let us know how it goes.:thumbsup: