Bought 5Eleven radiator guards…not having a good time…

[Firstgear]

I got two out of 4 holes drilled through. I still have two to go. I have broke more 1/8” drills than I can count. I have ordered some more drills (1/8 carbide and 3/8” tool steel) from McMaster Carr and will have them Monday. The 1/8th drill is first to get a hole opened that the 3/8th can just hog out the necessary material. I have used oil as well as cutting fluid to keep on the drills While drilling.

I was going to put it on my drill press but its not tall enough to work nor is my knee mill.

those that have done the drilling, any pointers? This shouldn’t be rocket science…but damn!

 

[lynnmor]

You may be running the 1/8 bit too slow, it should be running about 1200 RPM.

 

[Firstgear]

You may be running the 1/8 bit too slow, it should be running about 1200 RPM.

That could be the problem. I am usually machining aluminum…not steel.

 

[lynnmor]

That could be the problem. I am usually machining aluminum…not steel.

Aluminum would be much faster than that. Also, if you use carbide the speed would be higher as well. Any good quality steel drill bit is fine for this job, I had no problem doing the same install using ordinary HSS bits. I do have professional quality drill grinders so my bits are at least as good as new. I could give you exact speeds but with most hand held drills is only guessing anyway.

 

[GrizBota]

Probably pushing too hard as well, maybe at a slight angle. If the bit is sharp and lubed (actually it’s for cooling), moderate pressure, axially aligned with the long axis of the bit, with the bit a right angles to the work surface things will go ok. If you’re having trouble staying square, having someone that understands the concept spot you from 10 ft away can help. A magnetic square or level might help a little. Fortunately 1/8” drill bits are not too expensive. I bought a package of 10 or 12 of all the common fractional drill bits 1/8” and smaller quite a long time ago. Now when I bust a little one, it doesn’t even bother me. Recently I replaced all the missing bits from my Dad’s fractional, numbered, lettered drill bit set (apparently even he broke one now and then). It wasn’t too awful expensive. The letter bits are the most spendy of the bunch.

My Dad was an old school machinist, back when it took skill (not a programming degree). He made things look frustratingly simple. I’m a hack compared to what he was.

 

[Runs With Scissors]

Nice looking guards man..

5/11 makes nice looking stuff for sure.

I always default to "slower" when drilling steel.

Sharp bit, cutting fluid, mild to medium pressure and slow rpm, should get you through. (not sure on rpm, it's more of a "feel" thing for me, but if I was guessing 6-700 ish)

 

[mikester]

Don't buy cheap drill bits. I can drill more holes with a dull Cleveland or Butterfield than I will with a 100 new mystery cheapo bits.

Nice looking guards!

 

[mcfarmall]

Is your drill motor in reverse? RPM=4xCS÷diameter

RPM=4×90÷0.125
RPM=2880
These are theoretical values and should be "adjusted" for every case. I'd run around 1800-2000 based on my experiences. Back off on the feed pressure as you approach breakthrough. My bet is that's what's causing your breakage.

 

[Runs With Scissors]

Is your drill motor in reverse?

Embarrassingly enough.............Been there, done that.

 

[The Evil Twin]

You are probably going too fast. There is actually a formula for RPM based on diameter, material and feed rate.
Anyway, heat is the enemy. Like BBQ, low and slow. 200- 500 is probably good enough. You should see curly strands of metal coming out. Too fast and the cutting edge will overheat and not bite in. Heat and not drilling straight will break bits. If you are using a cordless, the trigger should be barely pulled.

 

[Bmyers]

I used a step bit. I made a divot with a punch and then used my step bit to drill to the whole size I need.

Spray a little WD40, Kroil, PB Blaster, or some type of lubricant while you drill. Not a lot a metal you are going through, so just a little will do and help protect the bit.

 

[GreensvilleJay]

I'm still trying to figure out why you can't use your drill press ?
I'd center punch, then hold the steel near '511' and drill the holes.
2nd choice, clamp to workbench and drill....

Am I not seeing this project right ??

 

[TheOldHokie]

I got two out of 4 holes drilled through. I still have two to go. I have broke more 1/8” drills than I can count. I have ordered some more drills (1/8 carbide and 3/8” tool steel) from McMaster Carr and will have them Monday. The 1/8th drill is first to get a hole opened that the 3/8th can just hog out the necessary material. I have used oil as well as cutting fluid to keep on the drills While drilling.

I was going to put it on my drill press but its not tall enough to work nor is my knee mill.

those that have done the drilling, any pointers? This shouldn’t be rocket science…but damn!



View attachment 104567

I had no problem using a 3/8" cordless drill and "cheap imported" HSS jobber twist drills. You do not need a carbide drill for this simple job and 1/8 is pretty damn small and easy to break. Move up to a little larger bit and slower speed.

The key is to start with a sharp bit and keep it sharp by running it well lubricated with a good cutting fluid, proper RPM, and adequate pressure. That OEM frame cuts quite easily with the correct tool and technique.

Dan

 

[Smokeydog]

Technique and tooling. Drill press stays on lowest speed 95% of the time. Maybe a little bigger drill bit for free hand pilot. Got a bag of 6mm stubby cobalt CNC drill bits at flea market many years (decades) ago. Sharp as a serpent’s tooth and can’t break or dull them. Pilot for larger holes. Most used drill bit in the shop.

 

[Pawnee]

If you try to use a 1/8" carbide bit in a hand drill you will break it.
Try starting with a 1/16" bit and don't forget to center punch the spot.

I just did this:
- Center punch
- 1/16"
- 1/8"
- 15/64"
- 1/4"
With cutting fluid. The steel was not very difficult to drill.

Adjust the last 2 sizes and maybe add another if you need 3/8" holes.

 

[Firstgear]

I'm still trying to figure out why you can't use your drill press ?
I'd center punch, then hold the steel near '511' and drill the holes.
2nd choice, clamp to workbench and drill....

Am I not seeing this project right ??

My drill press is a bench top. The holes to be drilled are marked on the inside. Once I get break through I was able to flip the guard over and get after it with the 3/8” drill. That was able to spit out nice pieces of steel.

 

[TheOldHokie]

Technique and tooling. Drill press stays on lowest speed 95% of the time. Maybe a little bigger drill bit for free hand pilot. Got a bag of 6mm stubby cobalt CNC drill bits at flea market many years (decades) ago. Sharp as a serpent’s tooth and can’t break or dull them. Pilot for larger holes. Most used drill bit in the shop.

Here is an inexpensive, accurate, and hard to break way to start freehand and machine drilled holes. Spot it then drill to full size.


A "cheap imported" #4 HSS double end center drill is less than $2. Step drills are sheetmetal, carpenter, electrician, and plumber tools.

Dan

 

[Downeaster]

I have found out that everything I try to drill on my Kubota tractor has steel made from kryptonite. i like you have broken many bits, and spent a lot of time. I do suggest a good cutting oil, as that does help and speed up the job.

 

[The Evil Twin]

If you don't see this, slow down till you do. You are going too fast.

 

[Firstgear]

Here is an inexpensive, accurate, and hard to break way to start freehand and machine drilled holes. Spot it then drill to full size.


A "cheap imported" #4 HSS double end center drill is less than $2. Step drills are sheetmetal, carpenter, electrician, and plumber tools.

Dan

View attachment 104586

I have those…from my mill….and used them. Good suggestion.