Your opinion on nibbler tools? (and other project enclosure techniques

[XOIIO]

Hey all, I recently saw dave's video on electronics shop essentials, and he mentioned the nibbling tool, I used one many years ago and have always wondered what it was because it was such a blessing to make a square hole in a metal project box, although it gets fairly tiring.

Tommorow I am going to get one, it will come in such handy because I an making more projects with small LCD's in ABS and other plastic cases (there is this sort of grey plastic, can't recall what it's called) and using a drill/dremel/file is super tedious and I can never seem to get a perfect fit, and don't have a CNC machine, I can only imagine the ease using one of those.

Anyways, I'd like to hear your opinions on cheap hand operated nibbling tools or other tips for making nice square cutouts in enclosures. I figure using the coping saw I grabbed for this purpose for the rough shape and using the nibbler and a file to refine the edges will give the best results. I usually make a guide in photoshop using my calipers and tape it to the box, although photoshop kind of sucks for lining up round holes at an exact distance from eachother just right.


Something else I want to get someday is a uni bit, we used one of those too and it was awesome but crap they are expensive!

Also any good accessories for drill presses? I got one for only $40 on kijiji and it works a treat (funny because my drill bit set cost more), I am going to use a hall effect sensor for a digital RPM readout which, while probably not super handy will be kind of neat I think. I'd like to get an adjustable x-y stage for it but those are pretty pricey as well.

[XOIIO]

Yeah, they do get tiring particularly if you are working at their capacity. You can get a drill attachment that does the same sort of job.
http://www.bunnings.com.au/sontax-nibbler-with-2-cutting-heads_p6320207
I haven't tried them and it might be overkill for an occasional LCD cutout.

that's pretty neat looking but probably overkill for small project enclosures.

I look forward to the day when you can buy drill bit kits for square holes at hardware stores for a similar price to regular bits, that would be an awesome future.

[Sigmoid]

Honestly, I think the field of small project enclosures is heading toward a revolution with 3d printing and all. (Though, I'm wondering if anyone knows a good openSCAD library of useful stuff like metric threads and similar.)

But yea, nibblers are a great tool.

[XOIIO]

Honestly, I think the field of small project enclosures is heading toward a revolution with 3d printing and all. (Though, I'm wondering if anyone knows a good openSCAD library of useful stuff like metric threads and similar.)

But yea, nibblers are a great tool.

Yeah 3d printers are awesome though 3 hours for a project box doesn't seem worth it when you could drive for 15 minutes and get one with a nice finish, threaded metal inserts and bottom sections in metal/plastic for a few bucks.

I'd like to get one of the relatively cheap laser cutters off ebay one day, just load up a template the size of the box, line it up on the stage and in a minute you have perfect holes all set up.

Well, at least for plastic anyways but that's pretty much what all my stuff goes in.

[Rory]

I have seen beautiful cutouts done with just a drill and some file work. It is all in the technique, and the amount of time and care one is willing to put into it. If you really want to learn some good techniques on producing nice looking work, look at how the homebuilt aircraft builders do it. 

There are lots of sites out there that will give you great tips. Your search engine term is "aviation sheet metal techniques".  EAA is a good place to start for direction toward what you want to find.

And like everything else, one must practice, practice, practice.  If I haven't done any sheet metal work for a while, I dig out a piece of scrap and work on the technique until I'm satisfied with the result - then I work on the finished product. These skills get rusty very quickly if you don't do it every day.

You can get pretty good sheet metal working tools through the homebuilt aviation marketplace. Aircraft Spruce in the USA has most of the tools you'll want, though you can find the same tools cheaper at other places once you become familiar with the market.

As far as nibblers, most folks I know that still use the hand nibblers go for the Klein. I have collected a couple-three of different ones from various mfrs over the years and the Klein seems to be the highest quality of the ones I have. With the others I sometimes get pinched between the thumb and index finger if I'm not real careful. For power tools, I also have a drill attachment which clamps down to the table top, and a Northern Tools air nibbler which gets the bulk of the work. These are only good for cutting thin metal - maybe to .062" thickness. But a caveat - power nibblers are tough to master and those that know how to use them make it look deceptively easy.

But most of all, a good set of files with handles are really the tools to have. Nibblers are good for roughing out the holes, but you need a sharp file of the right size to get the job cleanly done.

[VK5RC]

I have found my nibblers (admittedly not high quality) often leave a little scratch on the surface (where the smaller die has a small metal band hoop and return spring)
If I am real going for a super finish I use the multiple drill holes and file technique. Every time I use a drill stand for better results as well.
I have not used any of the online "make front panel" computer milled services, I would imagine great results but steep prices.
Having said all that I would get another if my nibbler broke today!   
Regards Rob

[Psi]

yep, nibblers are worth every cent.

Drill (hole for nibbler to fit through)
Nibble
File (if you need the edges perfectly smooth)

Its fast and produces really good results.

[XOIIO]

yep, nibblers are worth every cent.

Couldn't resist.

[G7PSK]

Monodex nibblers are the best hand nibblers IMO. I bought a set 40 years ago and in that time all I have had to replace is the center blade, about 3 times as they eventually break,usually when cutting St/St. I have had a number of other ones in that time and they all ended up in the skip but still have the original monodex, the chrome is flaking a bit now though the power one with the round pin with a lip although able to cut very tight corners, the pins tend to break very readily. Not a good idea to cut with a saw and then use the nibblers to clean the hole as they need the material on both sides of the blade to support it and stop it bending sideways and snapping.   

[GreyWoolfe]

I have a no name nibbler, have had it for years.  I don't use it that often, but when I need it, it is nice to have.  I would second getting a nibbler and a good set of files.

Tom, NW0LF

[XOIIO]

 Well, got mine and was excited to use it but the project box was too thick for it to nibble. Ended up having to using my drill press as sort of a band saw and file it down from those results which kind of sucked, but at least its a bit more accurate.

[Rory]

Monodex nibblers are the best hand nibblers IMO. I bought a set 40 years ago and in that time all I have had to replace is the center blade, about 3 times as they eventually break,usually when cutting St/St. I have had a number of other ones in that time and they all ended up in the skip but still have the original monodex, the chrome is flaking a bit now though the power one with the round pin with a lip although able to cut very tight corners, the pins tend to break very readily. Not a good idea to cut with a saw and then use the nibblers to clean the hole as they need the material on both sides of the blade to support it and stop it bending sideways and snapping.   

The Monodex looks a lot easier on the hands. I have always found my hands tire quickly and that the squeeze is quite awkward with the Klein and similar models.  Is this similar to the one you have?
http://www.ebay.com/itm/Edma-Monodex-Nibbler-Shears-Cutter-Sheetmetal-/350835378202?pt=UK_Hand_Tools_Equipment&hash=item51af6b081a

These are the ones I have in the toolbox:
http://www.ebay.com/itm/Klein-Tools-76011B-Wire-Cutter-Cutting-Nibbler-Tool-/301001264111?pt=US_Measuring_Layout_Tools&hash=item461512cbef

Another problem that gets put up with is what the nibbler does with the slugs. They tend to jam up in the  mechanism and need to be cleaned out occasionally. Is this a problem with the Monodex? The air nibblers leave a crescent moon slug.

I've pretty much left the hand nibblers in the toolbox and use an air nibbler which is much faster and easier on the hands. Just have to remember to put the foam plugs in my ears so I can save what remains of my hearing...

On openings large enough I use aviation snips and drill corner holes.

[Rory]

Well, got mine and was excited to use it but the project box was too thick for it to nibble. Ended up having to using my drill press as sort of a band saw and file it down from those results which kind of sucked, but at least its a bit more accurate.

Remember, a drill press is not designed for lateral cutting, that is, like a rotary mill. If you put sideways pressure on the thrust bearings they will wear more rapidly and you will find your press will only drill oval holes.

What do you mean, like a bandsaw? 

[Valueduser]

Yeah, they do get tiring particularly if you are working at their capacity. You can get a drill attachment that does the same sort of job.
http://www.bunnings.com.au/sontax-nibbler-with-2-cutting-heads_p6320207
I haven't tried them and it might be overkill for an occasional LCD cutout.

I've recently started working on some tube amp designs and have been wondering how the hell I was going to cut the square holes for the transformers.  This totally solves my dilemma.

[XOIIO]

Well, got mine and was excited to use it but the project box was too thick for it to nibble. Ended up having to using my drill press as sort of a band saw and file it down from those results which kind of sucked, but at least its a bit more accurate.

Remember, a drill press is not designed for lateral cutting, that is, like a rotary mill. If you put sideways pressure on the thrust bearings they will wear more rapidly and you will find your press will only drill oval holes.

What do you mean, like a bandsaw?

well, didn't really know what other vertical tool would be a good explanation of it. I did make sure to go fairly slowly though, and besides this drill press was only $40 (second hand for a nice mastercraft one), and I don't do that often. If I did do it a lot I'd get one of those fancy horizontal cutting bits.

[TerraHertz]

I've recently started working on some tube amp designs and have been wondering how the hell I was going to cut the square holes for the transformers.  This totally solves my dilemma.

Not necessarily. Those drill-attachment nibblers are intended for cutting thin roofing sheet metal and such. Something they are very good at in my experience, and in fact I don't know of anything else that can cope with corrugated iron roofing, since the cutting blade needs to stay perpendicular to the sheet. One thing to be careful of - the power nibbler produces large quantities of tiny crescent shaped metal swarf, which are extremely grabby-ouchy to skin and clothes.

Anyway, I'm pretty sure the drill attachment nibbler I have wouldn't work (or would break) if I tried to cut typical chassis thickness steel with it.

I know it's tedious, but lacking a big CNC punching machine you might be best to make the transformer holes the low tech way. Drill lines of 5mm or 1/4" holes as close to each other as you can, inside the final hole edge. Then cut the remaining metal bridges. Several ways to do that. One is to use the same drill bit in a hand electric drill, but drill diagonally, tilted 45 degrees or more in both directions along the line of drill holes. It's surprisingly effective.
Another is a big old pair of tough wire cutters - just chew the metal bridges away.
Then use a very coarse file to get rid of the bumps, then a finer file to get to your final hole outline. (scribed is best.)

Another way is a jigsaw. This is what I normally use these days. Drill 2 holes at diagonally opposite corners of the final square, just inside of the edge. Holes must be big enough to fit the jigsaw blade. Use square file (or the jigsaw, if you're good with it) to expand each hole to a flat where you want the cut edge to start. Use a blade tooth pitch fine enough that it has at least 1.5 teeth in the thickness of the sheet metal, or you're going to have a bad time. Cut the 4 sides starting at the holes.
If you don't want the chassis metal surface scratched up by the jigsaw foot (and the metal filings that will work under it), cover the area with gaffer tape first. Don't try to cut exactly on the line if you want a visually clean line, cut just inside it and file to finish.
There are a few things to watch out for with jig saws, if you've never used one before. Biggest one- NEVER pull the blade out of the cut with the saw still running. Turn the jigsaw off while still holding it down against the work. Wait till it fully stops, THEN remove it.

[XOIIO]

I've recently started working on some tube amp designs and have been wondering how the hell I was going to cut the square holes for the transformers.  This totally solves my dilemma.

Not necessarily. Those drill-attachment nibblers are intended for cutting thin roofing sheet metal and such. Something they are very good at in my experience, and in fact I don't know of anything else that can cope with corrugated iron roofing, since the cutting blade needs to stay perpendicular to the sheet. One thing to be careful of - the power nibbler produces large quantities of tiny crescent shaped metal swarf, which are extremely grabby-ouchy to skin and clothes.

Anyway, I'm pretty sure the drill attachment nibbler I have wouldn't work (or would break) if I tried to cut typical chassis thickness steel with it.

I know it's tedious, but lacking a big CNC punching machine you might be best to make the transformer holes the low tech way. Drill lines of 5mm or 1/4" holes as close to each other as you can, inside the final hole edge. Then cut the remaining metal bridges. Several ways to do that. One is to use the same drill bit in a hand electric drill, but drill diagonally, tilted 45 degrees or more in both directions along the line of drill holes. It's surprisingly effective.
Another is a big old pair of tough wire cutters - just chew the metal bridges away.
Then use a very coarse file to get rid of the bumps, then a finer file to get to your final hole outline. (scribed is best.)

Another way is a jigsaw. This is what I normally use these days. Drill 2 holes at diagonally opposite corners of the final square, just inside of the edge. Holes must be big enough to fit the jigsaw blade. Use square file (or the jigsaw, if you're good with it) to expand each hole to a flat where you want the cut edge to start. Use a blade tooth pitch fine enough that it has at least 1.5 teeth in the thickness of the sheet metal, or you're going to have a bad time. Cut the 4 sides starting at the holes.
If you don't want the chassis metal surface scratched up by the jigsaw foot (and the metal filings that will work under it), cover the area with gaffer tape first. Don't try to cut exactly on the line if you want a visually clean line, cut just inside it and file to finish.
There are a few things to watch out for with jig saws, if you've never used one before. Biggest one- NEVER pull the blade out of the cut with the saw still running. Turn the jigsaw off while still holding it down against the work. Wait till it fully stops, THEN remove it.

Dare I ask what happens if you remove it with it running? That's probably a mistake I'd have made.

[Psi]

Dare I ask what happens if you remove it with it running? That's probably a mistake I'd have made.

It's impossible to pull it out fast enough to clear the blade before it does another few down stroke.

The second the blade exists the material (at upper most blade position) it starts coming back down again.
It misses the small cut/gap it came out from and slams into the material your cutting.

Best case the jigsaw violently kicks back you get some scratches on your work-piece.

Worst case the jigsaw blade instantly snaps, bits of blade fly off and hit you in the eye.
The kickback then rips the tool out of your hands and it falls to the floor where the jagged remains of the blade still in the tool embedds itself in your foot.

[G7PSK]

Monodex nibblers are the best hand nibblers IMO. I bought a set 40 years ago and in that time all I have had to replace is the center blade, about 3 times as they eventually break,usually when cutting St/St. I have had a number of other ones in that time and they all ended up in the skip but still have the original monodex, the chrome is flaking a bit now though the power one with the round pin with a lip although able to cut very tight corners, the pins tend to break very readily. Not a good idea to cut with a saw and then use the nibblers to clean the hole as they need the material on both sides of the blade to support it and stop it bending sideways and snapping.   

The Monodex looks a lot easier on the hands. I have always found my hands tire quickly and that the squeeze is quite awkward with the Klein and similar models.  Is this similar to the one you have?
http://www.ebay.com/itm/Edma-Monodex-Nibbler-Shears-Cutter-Sheetmetal-/350835378202?pt=UK_Hand_Tools_Equipment&hash=item51af6b081a

These are the ones I have in the toolbox:
http://www.ebay.com/itm/Klein-Tools-76011B-Wire-Cutter-Cutting-Nibbler-Tool-/301001264111?pt=US_Measuring_Layout_Tools&hash=item461512cbef

Another problem that gets put up with is what the nibbler does with the slugs. They tend to jam up in the  mechanism and need to be cleaned out occasionally. Is this a problem with the Monodex? The air nibblers leave a crescent moon slug.

I've pretty much left the hand nibblers in the toolbox and use an air nibbler which is much faster and easier on the hands. Just have to remember to put the foam plugs in my ears so I can save what remains of my hearing...

On openings large enough I use aviation snips and drill corner holes.

Yes that's the one, the company has been taken over, they don't cut slugs but a continuous strip that coils up in front as you cut.