I need to make the 1 1/4 inch antenna hole in my fender and many of the posts state to use a greenlee punch. Want exactly is this? Do you need to purchase the punch and the 1 1/4 inch bit? I searched google and I still do not understand what this tool is and what I need to buy. Any explanations would be appreached. My fender is installed and it looks like you drill a pilot hole and assemble the cutter and base on either side of the metal which means no good for a installed fender. I guess I can take off the fender again :-( if I have too but alignment is so much fun I would rather not. If the punch is not the way to go what other suggestions would you guys have?? Metal hole saw attached to a drill??
As always thanks!!!

You can do it with a hole saw. Just drill a pilot hole first and have your antenna base handy. I think there is a notch in one side of the hole. I had all this on my hobbystage site, but that got elimnated so I am going by memory here. You can make the notch with a file. Take a look at the bottom of the antenna base.

I used the Greenlee hole punches. They are the only way to go (my opinion). Electricians use them to knock out holes in junction boxes. They start off at about the half inch diameter and go up to about inch and a half. I would hunt down an electrician, or an A/C repairman that you or a friend might know and use his hole punches. They may or may not be Greenlee, doesnt matter. Any way,you drill a few pilot holes starting with a small 1/16 inch bit and work up to the size of the screw that comes with the 1 1/4 punch. You dont buy a 1 1/4 inch drill bit. I really recommend doing this with fender off. I installed my fender and later on down the road found an OEM antenna, and had to remove the fender to punch the hole. Then get the small rat tail file and file your notch.

I'll explain how the Greenlee basically works, then I'll tell you to just use a holesaw because the fender is already installed.

Think of a plastic cup, then think of another plastic cup with the rim of the cup slightly smaller in diameter so that if you put them rim to rim, the smaller one would barely fit into the larger one. Then imagine a hole cut into the bottom of each cup and placing the cups, rim to rim, together and the all-thread slid through them both. The Greenlee works "similar" to this, in that you drill a pilot hole, put one "cup" on one side of the sheet metal, then the other "cup" on the other side of the sheet metal, then use the hydraulic pump that comes with it to squeeze the two cups together, which in effect, punches a hole the size of the outer diameter of the smaller cup (or inside diameter of the larger) into the metal. It creates a perfectly round, non-jagged hole with very little ease. It's much easier to use than a hole saw, and is easier to line up in the exact, correct location.

However, as I stated above, it's not worth removing the fender, just use the hole saw as Jonesy said using a pilot hole first and follow his instructions.

I put masking tape down first before drilling the hole for mine.

Here is what a manual one looks like, just put a wrench on the bearing cup side and the cutter hub on the other, and it will cut the hole out as you tighten...You might be able to thread the cutter hub inside the fender on the car, but as stated...taking the fender off is the way to go, (you might want to tape off the finish side with duct tape or similar to protect the finish)...good luck...Mike
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7576209306&category=25296

Thanks clwilcox33, I now understand. Would have been easy before I installed the fender. Didn't think about the hole until it was too late. Since I HATE aligning the body panels I will go with Jonesy's hole saw.
Thanks guys!!! I do have a second camaro to use to match the location and notch to.

You might think about using a step drill bit. Nice round holes with that bit.:thumbsup:

You might think about using a step drill bit. Nice round holes with that bit.:thumbsup:

True, but those little bits are expensive for just one bit. I haven't bought one yet.

Come to think of it, that is what I used. I borrowed mine from the body shop.

Bringing this one up again. The AIM says 1 1/8" hole. Is 1 1/4" or 1 1/8" correct?

greenlee punches do a very nice job......the area needs to be somewhat flat though.............otherwise it may distort the area.on a 1968 or 1969 it is not flat where the hole needs to be..

so i say use a unibit.a size 5 will get you the size hole you need.

I would use a unibit (step bit) myself, they make nice clean holes. Hole saw cuts are pretty ragged at best.
I use the greenlee punches a lot, I'm an Electrician, I actually have 2 manual ones at home for 7/8" and 1 1/8" holes, we use hydraulic ones at work generally, they go up to 5" I.D., (probably bigger actually).
One thing to remember for anyone not familiar with these punches, the size on the cup of the punch assembly is an I.D., so if you use a 1" punch, it will actually punch an 1 3/8" hole. You would use a 3/4" punch to get 1 1/8". Likely this would be caught, but you never know, just measure the cup first if not sure.

One thing to remember for anyone not familiar with these punches, the size on the cup of the punch assembly is an I.D., so if you use a 1" punch, it will actually punch an 1 3/8" hole. You would use a 3/4" punch to get 1 1/8". Likely this would be caught, but you never know, just measure the cup first if not sure.Would not those be called/labeled 1 CONDUIT & 3/4 CONDUIT respectively? Teach me something here....

I thought SAE diameters punched standard diameters, i.e., 3/4 = 3/4, etc.

Would not those be called/labeled 1 CONDUIT & 3/4 CONDUIT respectively? Teach me something here....

I thought SAE diameters punched standard diameters, i.e., 3/4 = 3/4, etc.

Good point Everett, I just went out and looked at my punch in the garage to see exactly what it says, and it says: 1/2cond7/8(and a metric # I forget now), so you are correct about that, I guess at work we only look at the first number listed and move on, since thats all that matters to us, it is however worth noting I guess, don't glance at the cup/ cutter and assume the first number you see is the hole size.
Now, as for the standard diameters deal, I have never seen a Greenlee set that does anything but KO's for electrical conduit sizes (OD), since they are an electrical tool. That means hole sizes are going to be 3/8" larger than the trade size, so 1/2", 3/4", 1", 1 1/4", 1 1/2", 2", 2 1/2", 3", 3 1/2", 4", 4 1/2", 5" add 3/8" to those sizes and thats your hole size. The dimensions are in line with electrical conduit sizes, not SAE standard sizes you would usually see.
Now that doesn't mean they don't make a SAE punch, but I have never seen one.

Uni bit, step bit, probably best way to go. Nice clean hole. Uni bits are also sized for electrical field. IE 1/2 in uni bit I believe will go up to a 7/8 hole, and the 3/4 bit goes up to 1 1/8. A pilot hole really make it easier to use the Uni bit.