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Tip: Making Holes ? Peacefully

Ironflight

VAF Moderator / Line Boy
Mentor
There are many ways to cut out an instrument panel. You can use fly cutters, air nibblers, hole saws, jig saws, die grinders, angle grinders, files, plasma cutters, water jets, laser cutters and even milling machines. I’ve used many of those techniques myself over the years. Lots of people let their pocket-book do the work, and hire it out to someone with one of the fancy computer-controlled cutting machines. But nothing, to my mind, matches the beauty, quiet, and precision of a good old fashioned Greenlee hole punch. No frenetic moving parts, no flying chips or dust. No worries about things going too fast, or getting out of alignment. No risk of injury or death. Just the silent spinning of the wrench and two nice “snaps” as the hole is punched – first one side, then the other.

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After building a number of panels over the years, always using what I had on hand, I finally sprung the few hundred bucks it takes to buy the combo punch (two hole sizes, 2 ¼” and 3 1/8”) you see in the aviation tool catalogs. All it does is punch instrument panel holes. Seems sort of pricy, huh? Well….if you pay to have someone cut your panel, it’ll cost as much – and if you are a multiple offender, you’ll save the money on the second go-around. If you use the fly cutter, your emergency room fees for bandages ALONE will be double that! ;) Besides, it’s nice to have a tool no one else in the neighborhood has – your contribution to the ”loaner pool” so to speak.

I know it is almost old-fashioned to build your own panel these days, but if you do, think about borrowing one of these little wonders. Mine sits in the dark drawer most of the time and is happy to go visit local builder’s shops. There is nothing new about them – they’ve been around forever. But they are completely goof proof, so long as you drill the center hole in the right place. Spot it with a #40, enlarge to 5/8” with a step drill, then slowly turn the screw with a nice long breaker bar until you hear the “snap” - Your hole is ready! A rare moment of shop silence these days is worth the price, believe me….

Paul
 
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Agreed

Anytime I can buy a tool to do the job myself for the price I would pay someone else, I always opt for the tool purchase. So when it came time to put some holes in an instrument panel, I did exactly the same thing. Such a satisfying process!
 
Amen to that...

There is nothing *quite* so satisfying as acquiring a new tool that can do quickly and cleanly what would take hours to do poorly otherwise - a fly cutter recently purchased for a wood working project was testament to that - hey! now I can make toy wheels! The opportunities, the new vistas, that a new tool can create... Much like the satisfaction that comes from having thought through, designed, made and used a wood working jig/template that works like a dream!
 
Well, not really "goof proof"...

...So there I was, using the Greenlee dual size punch on my instrument panel. I made all of the 3 1/8in holes, and several of the 2 1/4in holes. Boy, was this ever going well and look'n gooood. Now, I am on my last 2 1/4 in hole, top center of the panel, and there was no familiar 2-snap sound that I was expecting from the tool cutting through the aluminum.

Turns out that in my previously-successful-induced-complacency, I had inadvertently arranged the 3 1/8 die to the 2 1/4in punch and torqued down on the wrench. The aluminum did not get cut, but it sure did get distorted and bent. I was able to salvage the goof by beating it out with the flush rivet set and the gun.

Moral...nothing is goof proof!
 
Chief sells a punch that will cut a 3-1/8" or a 2-1/4" hole for $140. Save some cash while saving your fingers!:D
 
There is nothing *quite* so satisfying as acquiring a new tool that can do quickly and cleanly what would take hours to do poorly otherwise - <snip>

I wholeheartedly agree!!!

Ironflight; said:
Besides, it?s nice to have a tool no one else in the neighborhood has ? your contribution to the ?loaner pool? so to speak.

And to that end, my most recent purchase was a DMC AFM-8 Crimper which is available for loan to any builder in the Houston area. Best crimper I've ever used!
 
Making holes peacefully

Paul,
I couldn't agree more. I have a neighbor that use to be on a "Big Name" racing team. His job was to make instrument panels, and he has one of those Greenlee combo hole punches. I borrowed it for the Doll, Chris Parts beautiful RV-8. Mike Pratt's beautiful RV-8, and a couple of other times. What a great tool!

On my first homebuilt, a Pitts S1S, I use a fly-cutter. The cut finger didn't need stitches, and the nail finally grew back!
 
Just one downside. Round holes seem to be slowly going extinct dang it. Used to be those round holes were just about the whole gig. I wonder how much an "EFIS Punch" would cost?
 
Or borrow it

Can't remember who it was, but some generous soul on here loaned me their punch. That thing was a dream to use. All other methods suck by comparison. If only Greenlee made a pinhole filler.
 
Use a thrust bearing

Many years ago I borrowed and used one of these punches to make a new panel for my C-150. Great tool, but I found it worked much better after I bought a 5/8" ID ball thrust bearing from a local bearing house. Mind you I was cutting .090 aluminum. Also found the holes needed to be enlarged slightly to fit the instruments, used a 2" drum sander.
 
You sure about the 5/8" pilot hole?

Spot it with a #40, enlarge to 5/8? with a step drill, then slowly turn the screw with a nice long breaker bar until you hear the ?snap? - Your hole is ready! A rare moment of shop silence these days is worth the price, believe me?.
Paul

My punches have a 3/4" mandrel.
 
Greenlee is a brand...

Kind of like a Crescent Wrench (adjustable wrench), or "Vice-Grips"(locking adjustable wrench). Greenlee does make all kinds of punches but I dont believe they make the dual punch for aviation instruments but I could be wrong. Greenlee's main products are for the professional electrician.
No matter, whatever you call it, they are awesome and make quick easy work. I was lucky enough to borrow one for my panel.
There are square punches for common DB connectors but I dont think anything big enough for an EFIS or EMS.
 
answers:

1) For the EFIS holes? Much more noisy - cut-off wheel, drill holes for the corners, files to make the edges perfect, and scotchbrite disks to finish.

2) Yup Mel - 5/8" for mine. Just did four of them, and that's the size I drilled to for the mandrel with my step drill. Must be different manufacturers...

3) JonJay, you're right - I doubt mine was made my Greenlee - just used the term like (as you say) we use "Crescent Wrench" so folks know what 'm talking about. Wonderful thing to have in the box, no matter who makes it...

Paul
 
-Caution-

:eek: Electrician hole punches are "sized" differently. For example, a 2" electrical punch would NOT make a 2" hole, it would make the proper hole for a so-called 2" electrical fitting.

Just make sure if you buy a punch you are sure of the exact diameter of it.
 
Available for rent in the UK

For builders in the UK, Gloster Air Parts has one of these punches available for rent. Call Diana on 01252 617484.

Pete
 
Greenlee makes really good tools...but just a heads-up. I don't know if it was my ****-*** technique, or the wrong material, but here's what happened:

I borrowed an electrician friend's Greenlee set to make the hole in the firewall for the cabin heat vent valve (whatever size that was). The punch did *not* punch out cleanly, but instead, on one side, it grabbed the stainless steel and stretched it out, at the same time jamming it in between the male and female parts of the die. A royal pain in the @ss to remove, and took some additional clean-up on the firewall to make it look perfect again (fortunately, had some material to sand away with a drum so everything came out very nice in the end).

I think it was the relatively thin stainless steel...these things are built for thicker non-stainless (electrical boxes), so they work fine on thicker aluminum, but it sure was a booger on that thin firewall stainless.

YMMV...as I said, might have been something I did wrong, I dunno...but forewarned is forearmed.
 
I'll agree that these punches are great, as I am doing the new -8 panel, but even MORE satisfying than turning the ratchet until the "pop" is using a hydraulic press to do the work for you. Just a couple of pumps and you are through like butter.
 
but if you do, think about borrowing one of these little wonders.

For those in Minnesota, I have one for the two holes I cut in the instrument panel that's available to anyone who'd like to use it. (I also give out my engine hoist. I vaguely track it around the airfield and I think I know where it is at the moment.)

Someday I think it would be cool if someone would build a nifty Web site for an RV tool crib, where you could look up the tool you want to borrow, click on your state, and then get a list of people who've registered the tools they're willing to lend.

Anyway, I've got a couple of sizes of Greenlee punches and other assorted tools that people can borrow if they want.

BTW, there is a technique involved in using these things. You have to compress and turn, back off, shift the rotation and repeat. You want to do this about 7 times. Then you go for broke. If you try to go for broke on the first try, you're probably going to have a problem.
 
www.buildyourcnc.com

$2000, 3 months of work, learning software, test cutting, etc. but now I can cut a million copies of my panel no problem.

Learning a new skill....priceless. (oh, and it cuts square holes, round holes, and any other shape you want.)

PJ Seipel
RV-10 #40032
 
PJ,
Do you hire out??
Here's what the experience taught me: When you pay the $200-$400 that it costs to get your panel professionally cut either by CNC or waterjet, it is money well spent. I don't believe any of the guys who are doing it are making a huge profit. If you want a recommendation, I'd go with SteinAir.

I cut the first panel for my RV-10 by hand a couple years ago; it took about a month. Then Blue Mountain went out of business and I traded up for Dynon Skyview. Since I needed to redo the panel I wanted to be able to try out several different layouts in the plane. I looked at a number of different companies to get it waterjet cut, but didn't feel like I could adequately explain my layout without trying it out in the plane. I didn't want to send off a cad file, spend $200, and find out it wasn't what I was looking for.

So in the interest of experimenting, I built my own CNC (from the kit on the website I listed). I wanted to be able to play around with different panel layouts and because I'm fascinated with how CNC machines work. The machine I built has some limitations (the one I built won't cut a full panel at one pass; I had to do half and then shift the panel 12" to do the other half) and it is not as rigid as a commercial machine built out of metal, so I had to cut at much slower speeds in order to keep the accuracy. After cutting several test panels out of lexan, I cut 2 trials out of .032 (to test instrument fit) and then the final out of .063. Each panel took almost 8 hours of cutting. The machines the big boys are using probably take less than an hour per panel.

End state, I got the panel I wanted with extremely accurate cutouts (to .001) and a machine that will cut some neat patterns for things like cabinets, etc. But it wouldn't be usable to hire out because it's way too much work to cut a panel; between the cad/cam setup and the "supervision" of the actual cutting, I'd never have time to work on my RV-10. That said, if anyone is in the Jacksonville, NC area and wants to come by and learn some CNC or just BS about RV's, let me know. I'll be here until next summer; I don't deploy until about June.

PJ Seipel
RV-10 #40032
Extremely slow build...
 
The CNC sounds pretty neat PJ....but just in the interest of not scaring novice builders away, it really doesn't need to take all that much time to cut a panel using standard building tools. It's just another RV part after all. Laying it out is just drafting, and then cutting is just accuracy. I've probably done half a dozen complete panels in my life - takes me a couple of hours to cut them out, including square holes.

Not disputing that CNC sounds cool - but I'd hate for folks to get the wrong idea on how tough (or easy) it can be. Besides, new blanks cost what - $60? Nowhere near as bad as messing up a canopy....:(

Paul
 
I agree completely and my intent wasn't to scare anyone off at all. You're right that it isn't hard, although time might be somewhat dependent on how complicated your layout is. Practice helps a lot When I said my first one took a month, I should have said "it took a month of Saturdays." My problem is that I hate sanding and filing, so my tolerance for those tasks is very low before I have to go do something else for a while. I did not buy a punch tool, so I cut the round holes with a fly cutter originally. I also put a number of 3/4" square switches and lights in my panel and cutting out square holes that small was a pain. My response was just another perspective on a skill I chose to learn while building my 2nd panel. It validates that if you chose to have your panel professionally cut, the price you're getting charged for their labor and expertise is very reasonable. For me, it also meant no filing or sanding beyond a light deburring.

And fortunately the windows on the RV-10 are much easier to cut than the canopy on the other models. Every time I read one of those threads I am thankful I didn't have to make a "big cut" like that.:)

PJ Seipel
RV-10 #40032
 
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