TF - How To Drill for Guages?

[Dan in Pasadena]

How can I drill 3 each 2" holes perfectly centered on the prior knob locations? I plan to mount guages in place of the factory knobs.

Short of temporarily welding metal behind the holes the only way I can figure to do this is to clamp a piece of wood behind the existing holes, use the wood to have someplace the pilot holes for the hole saw can center on. Any other ideas? Anyone else done this? If you have I'd love to see pictures of the finished install.

[midnight rambler]

Use a greenlee electricans punch

[Dan in Pasadena]

Hmmm, I'll do a search. Is this a prohibitively expensive tool I'll never use again? Can I rent this?

[Dan in Pasadena]

Greenlee 7211BB-1-1/2 Slug-Buster Knockout Punch...
Is this what you're talking about? Do you just mate the two pieces and tighten the center bolt? Does this deform the sheet metal around the hole at all?

[ChuckDriver]

Here you go!

[1project2many]

Hey Dan...

I've wanted a set of Greenlee punches for years. Lotsa money for something I don't use often. I've borrowed a few from an electrician friend though.

You can drill and screw or rivit pieces of steel to the back side of the dash and then use your hole saw carefully. Keep the screws / rivits inside the circle that you are cutting out and there will be no permanent damage. The wood may not be a bad idea either. When cutting large circles with the hole saw the saw tries to walk around once the blade makes contact. The more support you can provide to the bit the better. So a 3/4" or 1" piece of wood might be more effective than a piece of 16 gauge steel. If you haven't used a hole saw with sheet metal you might want to try practicing first. Cutting clean holes in uneven surfaces can sometimes be tricky.

[Stepside Jim]

Hey Dan, one method a couple of us use for cutting holes in odd shapes is using an 1/8" drill bit. Sure it requires patience, but it does get the job done.



Drill while staying within the drawn circle.


After use of the rotary brrr, the edges are all cleaned up.


New piece welded in.


Probably a procedure you might not want to use but in the future it might come in handy.

[midnight rambler]

Originally Posted by Dan in Pasadena

Greenlee 7211BB-1-1/2 Slug-Buster Knockout Punch Unit, 1.951-Inch - Punchdown Tools - Amazon.com

Is this what you're talking about? Do you just mate the two pieces and tighten the center bolt? Does this deform the sheet metal around the hole at all?

that's the one Dan, I have a set here in San Diego don't know what sizes off hand, your more than welcome to use it if we can figure a way to get it to you.

[Dan in Pasadena]

Thanks you guys!

JJ, thanks for the pictures. I originally intended to leave my dash stock but have played with the idea of putting 3 guages in place of the original knobs. Speaking just for myself the stock dash is a bit too busy. Seeing these photos confirms it for me. I like seeing a dash that's been totally smoothed or sometimes with only the original radio in place. But really? Isn't the purpose of a dashboard to place the controls?

JJ, You know I tend to like your taste. Did you save these pictures because you were going to do something like this before you went to the Impala dash?

[YukonXL04]

Just clamp a piece of wood behind the hole, and use a hole saw. The wood will keep the bit centered.

[Dan in Pasadena]

Thanks Yukon!

JJ, This isn't the place for it I suppose but I found two sets of Cameo bedsides in the last two weeks. One set for $750, the other asking $1600 with tailgate & "trim"! Neither had bumper cover. I let them pass, I don't know anything about details of Cameo and didn't even go look to see how good/bad the bedside conditions were. I also just found out Gibbons offers a complete Fiberglas bumper cover. Partly I didn't pursue because I figured the missing parts were unobtainium! Lol.

[_Ogre]

screw a piece of wood to the inside of the dash through the 2 outer holes for the center hole
the 2 outer holes will need the hole saw off the center, otherwise a 2'' hole will be in the ashtray or heater switch hole

[Dan in Pasadena]

Originally Posted by _Ogre

screw a piece of wood to the inside of the dash through the 2 outer holes for the center hole
the 2 outer holes will need the hole saw off the center, otherwise a 2'' hole will be in the ashtray or heater switch hole

Thinking of deleting the heat control panel and ashtray anyway. Like I said, there's just TOO MUCH STUFF going on, on a stock dash for my taste.

I just haven't decided how much stuff to eliminate.

[ChuckDriver]

Yea, Dan I did consider doing the 3 gauges and moving the heat/AC controls over to the ash tray slot before deciding on the Impala dash.

Are you doing the cutting before paint?

And, I've mentioned this before, but painting the back of the dash white does a great job of brightening up things under it!

I'm seeing more Cameo bedsides pop up for sale, but the trim is expensive!

[roger55]

Draw the circles and use a 1/4" shank carbide burr in an air-powered die grinder.

[Dan in Pasadena]

I've liked the idea of the three gauges for awhile but looking at the pictures JJ posted makes me think they just clutter up the dash more.

I don't smoke so I have no need of the ashtray or cigarette lighter - at least in its original position. The throttle control is an anachronism that no one needs as far as I can tell. And the wiper controls will move to the ididit column I'm installing - all this means I can delete the three knobs. The ashtray/heater controls should either both stay or both go. I suppose I'd leave the original radio holes as I plan to use a Retrosound radio.

[1-ton of fun]

i was thinking of drilling the dash for gauges and my plan was to smooth it first then drill the holes.

but now i'm looking at doing dual 3 3/8" gauges: one quad gauge and a speedo/tach combo. both in a gauge panel in the factory gauge bezel.

[YukonXL04]

Originally Posted by 1-ton of fun

i was thinking of drilling the dash for gauges and my plan was to smooth it first then drill the holes.

but now i'm looking at doing dual 3 3/8" gauges: one quad gauge and a speedo/tach combo. both in a gauge panel in the factory gauge bezel.

Got a link for such gauges? I might rig my 50 up with something like that until I can afford to get stock replacements. man those are expensive

[_Ogre]

Thinking of deleting the heat control panel and ashtray anyway.

if you delete the ashtray, cut it out with all the structure behind it
i did not and have cut my hand numerous times running the new wire harness and install the ac
not enough room behind our dashes to run much of anything

[Dan in Pasadena]

Originally Posted by _Ogre

if you delete the ashtray, cut it out with all the structure behind it
i did not and have cut my hand numerous times running the new wire harness and install the ac
not enough room behind our dashes to run much of anything

Excellent advice. you mean take the face off the ashtray first to use as the repair metal? Or is there other structure behind it as part of the dash structure? I don't think I've ever looked up there.

[roger55]

Yes, I used the front of the ash tray to repair the hole with. Worked well.

I deleted mine because I wanted to location the ignition switch in that location.

With an Ididit shift column, the shifter arm blocks the access to the key switch when using the original location.

[Dan in Pasadena]

Good info, thanks Roger. Man, your (wife's) truck is so beautiful.

Questions:
1. Any particular reason to place the AC vents in the dash as opposed to the kick panels or a valance below the dash? Or strictly for appearance?

2. Also, do you know a good source for different styles of AC vents?

[Coupeguy2001]

Here's mine during the wiring of my electrical mods. I used a chassis punch to make the gauge hole. didn't even mess up the paint! That's a 55 passenger radio

[_Ogre]

Or is there other structure behind it as part of the dash structure?

there is a lot of structure behind the dash; sides to hold it and a top & back to keep fire in the ashtray from spreading
pull the tray out by tilting down and you can see what i mean