Need to drill 4" holes in stock bumper - how?
 

OK... silly question. I'd like to put auxiliary backup LED lights in my stock chrome bumper to add light at night when backing, closing gates, hooking / unhooking trailers, loading bikes, etc.

But what is the best / easiest way to drill a 4" hole into the bumper so I can install the lights?

I want them flush or sunken so as to limit damage.

TIA,
CORed

If you have one of those dremel tools, they are great for stuff like that. If not you could drill a pilot hole and use a jig saw, if the lights your using have the rubber grommets around them they will hide some of the imperfections if your off a little

I just did this mod and used my factory driving lights in the holes , tricky job lost of measureing and I used a jig saw . Ya have to cut the grommets and remelt them back together to fit the lights. I'll try and post a pic.

What would be wrong with using a hole saw? You know.....the kind that goes in a drill? They make them for metal.

Might work but bumper is not flat and I think it would bite a little , plus in my case the hole had to be just the right size and was not near any of my hole saw sizes.

Heres a pic not a close up though.

It takes a steady hand, but I have done it before. Front bumper and grill guard I installed for a customer had to have a couple of 2" holes in the bumper. Like I said.....slow and steady!

I would buy a good metal hole saw and just take it easy with it like VZ said.

two words that help a lot : weather stripping... makes up for not so perfect cuts, and gives the edge a nice finished look.

I used door edge guard from Walmart! Put the slit at the bottom, and it looked VERY slick! Cut it with tin snips.

Good metal hole saw... take it slow, but not too slow to where it is real grabby.. should be easy enough

I use norseman drill bits with lennox holesaws. Predrill the 1/4" hole and like the others said take it slow.

So a metal 4" hole saw seems to be the recommendation after drilling a pilot hole. Awesome... thanks guys.

BTW, the standard 4" lights that squeeze into the rubber grommet... are they just UNDER 4" so they fit into a 4" hole cut by a hole saw?

Thanks much! I'll be looking for a 4" hole saw soon.

CORed

Be prepared:
A quality 4" hole saw is not cheap. Add more if you have to get an arbor.

If you pre-drill the 1/4" center I prefer using 1/4" stock in the arbor. On an uneven surface a drill in the arbor can easily oblong the pilot hole.

HOly s%$#@....I think you need to change your user name to "top heavy." No high speed turns for you.

whats the rating on that alum bed mount?.....pretty cool!

Wallyworld has some 2" fogtype lights for $15 you could mount under the bumper. I did this and it throws 55watts of light back there when in rev. Of course my bumper is 2.5ft off the ground so if they get crushed I'll probably have more to worry about than those lights.

Yeah, I just threw some rubber tractor lights up under my bumper. Plenty of light, and they're about 10 bucks each at Tractor Supply.

I would use a Bi-Metal holesaw bit and use a punch to mark your hole then drill a pilot hole. You shouldn't have a problem just make sure you take your time.

I think that picture is lacking a third ATV forklifted across the first two.

Like "cribbing"




I have a feeling that chrome plating will flake and peel at the edge where it's been drilled.

I think that you would have to use a 3 3/4" instead of the 4" the teeth make it a little larger than 4. Atleast the ones that I have used before.
Later,
AC

I have mounted the oval STT with the rubber boots in 4 chrome bumpers. Due to the shape & style of the Dodge bumper I feel that the oval lights look better. For those, I use an open mounting bracket for the light as the template. After taping off the bumper, I measure, measure, and measure again. Using the template, I now make my outline on the taped bumper. Using a 2" hole saw, I cut the outer ends, then use a sawzall for the straight cuts between the circles.
For clean up, use a grinding tool, or hand file. When finished, I use some touch up primer on the cut out just to prevent any rust. I have never had any chrome chip or flake. I find the best trick is to have a helper who can keep oil on the surface while using the hole saw. The straight cuts go very easy. The rubber boots fit flush, push in the lights, and wire them up. I don't have a digital camera, so I can't supply photo's. I know it was off the subject of the 4" round hole, but if you steady with a sawzall, you can do a "rough" circle with it since the rubber boot will cover the outer part of the opening.

Good luck.

Jim

Its good for 1500 lbs , turns are not too bad , its just tuching the overloads that helps a little I think. To answer one of the questions ,I have no flaking of the chrome around the holes yet and I,m in the major salt belt.

OK... can someone please confirm this before I buy any hole saw. What size is the hole itself suppose to be and what size hole saw makes the correct size?

As far as the oval lights, I like that idea and can visualize what you did based on your description. I'll consider that.

I also have previously had small, cheap fog lights mounted under the bumper, but broke them one at a time over a couple years. Mainly caused by snow.

BTW, how many holes should a Lenox bi-metal hole saw make in a bumper before it's worn out? Just curious.

Your best bet is take your grommet to the store and hold up the hole saw to it , there is a lip on the grommet that holds it in the bumper and the hole should be a little smaller than that. This way ya can't go wrong if your going the hole saw method. Being a electrician I have every size hole saw known to man but none were the exact size I needed thus me useing the jig saw.