How to drill 2" hole in chrome bumper.

[N80]

I have a 2003 F150 which I use tow a 19' flatbed trailer. The female 7 pin plug assembly is attached to the bottom of the bumper with a metal bracket that hangs down below the bumper. Recently this assembly has been damaged twice because of its location.

I would like to put it in the bumper itself just to the driver's side of the license plate area.

This will require me to drill an approximately 2" round hole in the bumper along with 4 small screw holes to hold the plug assembly to the bumper.

I have a good powerful drill and I have various punches and decent regular drill bits but nothing that will drill a 2" hole.

What do I need to drill a 2" hole in a chrome bumper? Are there any special precautions or techniques I need to use with chrome? Cosmetics are not a concern. The truck is ugly and beat up.

Thanks for any assistance here.

 

[kennyd]

A regular bi-metal hole saw available at Home Cheapot or Lowes will do the trick easily. Use low speed and some oil.

 

[jenkinsph]

I think I would try a 2" hole saw with a 1/4" pilot bit. I would start by drilling the pilot hole first using a separate bit. Then insert the pilot bit and hole saw and give it a go. Go slow because a large hole saw can twist that drill around and hurt you if it binds up. I would also recommend you buy the better quality hole saw and a good arbor for it. It may take two hole saws because chrome is tough to drill and work. Once through the chrome plate the rest is easy enough.

Go slow and use cutting oil or other coolant.

 

[N80]

Thanks guys. I wasn't sure a hole saw would work but I'll give it a try.

Kenny, love your web site!

 

[Soundguy]

It will.. I've drilled stainless counter tops in industrial kitchens. use a piloted hole saw, bi metal, slow speed, and oil, as mentioned.

 

[muddstopper]

a hole saw will work just fine, I have drilled several bumpers with no problems. I do suggest you predrill the pilot hole and when using the holesaw, to go slow, not trying to apply to much pressure. Let the saw do its thing without trying to force it and it will last you for several holes. A good cutting oil really helps.

 

[PILOON]

When using a hole saw I resort to a little trick that I learned,
I drill a 1/4" hole and then remove the drill bit and replace it with a hard 1/4" rod or piece of shafting.
Reason being that the drill bit continues to cut the sides and widen the pilot hole which results in an oversized hole from the hole saw wobbling action.
I also once ground off the outer edges of a hole saw teeth to get an even more accurate hole. (hole saws have staggered teeth for wood work to clear passage)
\
PS,using your grinder, grind away the chrome B4 attacking with the hole saw should help.

 

[the old grind]

Better to use water than a 'lubricating' oil when cutting. If you have 'black oil' (sulpherated) use it.

 

[npalen]

The nickel and chrome plating are probably less than .001" total thickness

 

[N80]

I've got water, WD-40, motor oil, 3-n-1, spray lubricating oil and thread cutting oil like you use with tap and die. Which one? The cutting oil is thick and a little tacky to the touch.

 

[the old grind]

Thread cutting oil. Also Cool Tool 2, Tap Magic, Anchor Lube, or the machinist's original favorite... rendered pork lard.

It's about shear and surface tension that good lubes deter action 'in the cut', and it's cooling that's more important to minimize work-hardening metals with more than the 2`0 points of carbon (.2 %) of mild steel.

Watch your chips to see if cutting well, and don't overdo the rpm. (100-200 is plenty fast) Keep it cool (workpiece) if you want the tool to last.

Pre-drill center, and switch to a solid pilot to minimize wobble and make a cleaner hole with less wear on cutting teeth.

 

[kennyd]

Thanks guys. I wasn't sure a hole saw would work but I'll give it a try.

Kenny, love your web site!

Thanks George!
Use that thread cutting oil...

 

[dickfoster]

I have a 2003 F150 which I use tow a 19' flatbed trailer. The female 7 pin plug assembly is attached to the bottom of the bumper with a metal bracket that hangs down below the bumper. Recently this assembly has been damaged twice because of its location.

I would like to put it in the bumper itself just to the driver's side of the license plate area.

This will require me to drill an approximately 2" round hole in the bumper along with 4 small screw holes to hold the plug assembly to the bumper.

I have a good powerful drill and I have various punches and decent regular drill bits but nothing that will drill a 2" hole.

What do I need to drill a 2" hole in a chrome bumper? Are there any special precautions or techniques I need to use with chrome? Cosmetics are not a concern. The truck is ugly and beat up.

Thanks for any assistance here.

I'd use a good bimetallic hole saw. Get a good one made by Milwaukee or similar. Use some WD40 or something for cutting lube. Take your time and let the saw do the work. Don't try to rush it or you're likely to work harden the steel and make it just that much harder to cut and dull the cutting edge.

 

[dieselcrawler]

Lots of good advice.

Ive done this mod to my F250. Don't understand why its under the bumper in the first place. Bad design. At least our Excursion had its bracket tucked up to not hang lower than the hitch frame.

Hole saw should eat thru that bumper easy, even dry. However, I am a big fan of lube, rarely drill any metal without it. Couple self-drilling screws will easily hold the new trailer wiring plug in place.

Dont worry about it, easy job.

 

[Fallon]

WD40 is a crap lube, no clue why people still buy it. It stands for Water Displacement formula # 40. It displaces water well, but doesn't penetrate or lube well & definately doesn't stay around. Spray 1/4" in a cup & come back in a week. It will be empty & covered in a nasty yellow varnish.

Get a real penetrating oil or lubricating oil next time you are at the store. Sulfated tap cutting oils are the best cutting lube.

 

[dickfoster]

WD40 is a crap lube, no clue why people still buy it. It stands for Water Displacement formula # 40. It displaces water well, but doesn't penetrate or lube well & definately doesn't stay around. Spray 1/4" in a cup & come back in a week. It will be empty & covered in a nasty yellow varnish.

Get a real penetrating oil or lubricating oil next time you are at the store. Sulfated tap cutting oils are the best cutting lube.

Well I'll tell ya what. I was using a hole saw on some stainless steel tubing once. I think it was T304 stainless. I was using a brand new Mailwalke bimetallic hole saw, not a cheap piece of junk. I was using using cutting oil but the workpiece would work harden and eat the saw in nothing flat. A can of WD 40 was sitting so out of desperation I tried that. Imagine my surprize when the saw went through that stainless like butta. Now I reach for the WD40 can when cutting or drilling something like that although I'm a PB blaster fan for penetrating oil. When I stumble onto something that works, I tend to try it the next time around too.

 

[N80]

WD40 is a crap lube, no clue why people still buy it. It stands for Water Displacement formula # 40.

I use it for water displacement. ;-) And when you use it for what it is made for it works great.

The main reason I don't use it anymore is those crappy spray tops.

 

[Soundguy]

thread cutting oil.

 

[Egon]

Assuming it's a vertical surface the oil may have a little trouble sticking around?

Use a continuous water spray to keep it cool.

 

[Ford850]

First, make sure there is nothing tucked in the back side of that bumper that will interfere (wires etc). Then just predille, and saw the hole. Guys cut these in all the time for rear lights, and some use dremel or roto tools. A hole saw is a piece of cake. You'll be done in less time than it's taking you to read all of our advice.