Square holes on aluminum....  how do you do it? - Page 1
Forum section: electronics / projects

author: tkamiya
author_rank: Super Contributor
timestamp: October 09, 2019, 02:24:01 am
content: I am placing one of my project in an aluminum rack case. Front panel is 2mm, top and bottom is about 1.5mm, and sides are 3mm.I do not own any mechanized tools. All hand tools, bench drill press, and manual tools. I just broke my dremel.I always disliked making non-round holes. But for RS232C (9 pin) and power connectors, square holes are necessary. My usual method is draw out the outline, drill holes inside it along the line, use whatever is available to connect the holes, then file, file, file.... It's time consuming, and prone to slips to cause cosmetic problems. I can do pretty precise crafting but boy - it takes time.....Does anyone know a better way? What I've already excluded are farming it out to pros, buying mills, and hydraulic punches.

author: sokoloff
author_rank: Super Contributor
timestamp: October 09, 2019, 02:27:22 am
content: I use a square nibbler I bought at radio shack many years ago. I’ll see if I can find a modern listing.

author: sokoloff
author_rank: Super Contributor
timestamp: October 09, 2019, 02:28:24 am
content: Tryhttps://www.amazon.com/ProsKit-900-215-Nibbler/dp/B000BN60XW/

author: digsys
author_rank: Unknown
timestamp: October 09, 2019, 02:55:09 am
content: I used to have a punch set for all sorts of connectors - used both hand press and hydraulic press types. If you're only doing a few, likely not worth while, but damn awesome for production. Also had a set of basic punch tool shapes that you just placed the sheet down and whacked out desired shapes. Worked fine

author: texaspyro
author_rank: Super Contributor
timestamp: October 09, 2019, 02:55:43 am
content: You can buy chassis punches for most DBxx connectors. They are a 2-piece punch. You drill a hole, feed the bolt through the hole, place the second piece over the boltm and crank down a nut. The punches (made by Greenlee, etc) can be rather expensive, but occasionally can be found on Ebay for affordable prices.

author: tkamiya
author_rank: Super Contributor
timestamp: October 09, 2019, 03:09:48 am
content: This is the WINNER! Thanks! Some of these and nibbler should take care of my needs. Although.... nibblers I had in the past could not handle more than 1mm thick aluminum. Cutting blade would bend and eventually break off.I think I just need DB9 and AC socket type to get started.ps. Wow... db25 kind is going for $500 new at Amazon! and this is just for the punch itself!

author: Bud
author_rank: Super Contributor
timestamp: October 09, 2019, 03:15:09 am
content: All of a sudden farming it to pros does not look that bad anymore ?

author: tkamiya
author_rank: Super Contributor
timestamp: October 09, 2019, 03:43:04 am
content: Well..... all the sudden, drills, files, and a couple of band-aids doesn't seem so bad....Farming it out is OUT because of the way I make things. I do in steps. It's just too inconvenient to make several trips to the shop. For my current project, I ran into few problems. Now, I have to remove the front panel, add two DB9 holes and 1 hole for LED.As far as Greenly punches go, I was reading up some. For aluminum, the spec for the punch is 3.2mm. That's awfully close to some of the rack panels. I really don't want to buy mills as I was never trained to properly use it.

author: drussell
author_rank: Super Contributor
timestamp: October 09, 2019, 03:47:52 am
content: Quote from: tkamiya on October 09, 2019, 03:09:48 amYeah, the "real" ones meant for daily production use are rather pricey.There must still be a source somewhere for chinesium-grade punch sets that are suitable for occasional use or hobby type applications. I recall seeing a set of all five D-sub sizes and the drawbar tool for about $150 in the back of some electronics magazine or maybe in Computer Shopper or something, manymanyyears ago. Seemed like a great deal, even if they weren't very robust.I almost bought a set since in those days I used to fairly regularly have to cut extra port holes into the back of computers being built, upgraded or modified back then, but I never did get a set. Most of the chassis we were dealing with started coming with ample cutouts, even some with knockouts for the big SCSI connectors, although I wished I had a set many times later when building some other random projects, etc. as well.They aren't that difficult to make (random dies and punches) strong enough for aluminum, plastic or very thin steel, I've made a few purpose-built ones over the years for various things, but if someone can find a source of some pre-made ones in some common modern styles, etc. it would be convenient.I usually end up doing most of my panels on my old 1980s Dahlgren Wizzard XL computerized engraver. It's a bit of a pain to set up to cut panels and such compared to today's modern generic CNC router systems, but what do you expect for a 30+ years old system with TRS-80 internals for brains that was intended for doing things like making signs.I'm just glad the thing still works!

author: PixieDust
author_rank: Frequent Contributor
timestamp: October 09, 2019, 04:20:58 am
content: Use square drill bits.But yer, files are the way to go.

author: rpetitho
author_rank: Contributor
timestamp: October 09, 2019, 04:21:45 am
content: I used a combination of drills and jigsaws on my isolation transformer enclosure. Worked pretty good for bigger holes. Smaller holes are a different challenge.-Bob

author: viperidae
author_rank: Frequent Contributor
timestamp: October 09, 2019, 05:40:49 am
content: Square drill bits are just for wood aren't they?

author: beanflying
author_rank: Super Contributor
timestamp: October 09, 2019, 06:00:33 am
content: Nibblers for the win on thin sheetmetal and even plastics but you are limited to about 2mm max. The best bit is if you are working in enclosures with other electrical stuff still inside then the chips are way less floaty and easier to cleanup than every other method. Minimal buckling as well on even thin materials over using tin snips or shears.I would seriously love the money to spare for a set of hydraulic punches but it would be a total indulgence and so drills files and a Dremel for the other jobs.Tips - Masking tape for the tool side (not the die side) to minimize scratching and buy a deburring tool (the blue handled thing) and use your Laser Cutter to do the mark out for accuracy

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: October 09, 2019, 06:05:58 am
content: Buy a cheap CNC router machine from China. Something like thishttps://www.aliexpress.com/item/32919397764.html?spm=a2g0o.productlist.0.0.54db57f5O012h9&algo_pvid=c1d5f8e0-b557-4959-bcf6-b11b82acb20c&algo_expid=c1d5f8e0-b557-4959-bcf6-b11b82acb20c-7&btsid=e9376042-133e-4e2f-8bca-df0b401da4fa&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_53It can cut any shape on metal sheets and it is really precise for hobbyist. I have the same one and have cut square holes on 1.6mm thick Aluminium sheets.

author: GeorgeOfTheJungle
author_rank: Super Contributor
timestamp: October 09, 2019, 06:39:10 am
content: Three great tools:

author: mikerj
author_rank: Super Contributor
timestamp: October 09, 2019, 11:26:46 am
content: Quote from: viperidae on October 09, 2019, 05:40:49 amYou can broach square (or other shaped) holes in metal, and you can use a rotary broach for symmetrical shapes, but it's not a drill bit.

author: dom0
author_rank: Super Contributor
timestamp: October 09, 2019, 02:27:17 pm
content: Good files make very quick work of aluminium. Make sure you are actually using an aluminium alloy that can be machined; AlMg1 for example is very hard to machine due to its softness, but commonly sold on eBay etc. because it's cheap. AlMg3 is better and proper machining alloys areveryeasy to work - you can drill them easily, get excellent chips, very little burrs etc.You will also immediately notice that a front panel from a higher grade alloy is much more rigid and doesn't bend nearly as easy as a panel made from a low-strength alloy like AlMg1.Chalking files reduces edge build up drastically and prevents chips getting stuck in the files. Make sure your drill bits don't have built up edges. For D-Sub connectors you want a round file to work the corners, diameter of around ~5 mm.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 09, 2019, 03:07:55 pm
content: Punch, punch, punch... (and Judy?)

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: October 09, 2019, 04:29:08 pm
content: We have a shop near here that does a great job on electrical panels using a waterjet cutter. Not very expensive either.

author: langwadt
author_rank: Super Contributor
timestamp: October 09, 2019, 04:37:55 pm
content: jewelers saw?

author: duak
author_rank: Super Contributor
timestamp: October 09, 2019, 05:45:00 pm
content: Been there, done that. I spent hours filing square & D shaped holes in both alum, steel & stainless steel.Some tools that helped me are:- nibbler,- good files and a file card to clean them. If you don't have handles for the smaller ones use wire nuts from electrical wiring - just screw them on & save your fingers,- stepped drill bit (Unibit et al) for sheet metal - these bits don't grab sheet metal like twist drills do - get one!- tapered reamer to enlarge holes,- wide heavy black ink marker & sharp scriber to mark outlines and center lines,- sharp center punch - automatic center punch even better,- edge & hole deburring tools,- vise and rubber faced jaws,

author: L_Euler
author_rank: Regular Contributor
timestamp: October 09, 2019, 10:58:35 pm
content: Get a scroll saw off eBay and a handful of round abrasive blades. You can then dress the corners with needle files.

author: KL27x
author_rank: Super Contributor
timestamp: October 09, 2019, 11:43:15 pm
content: QuoteYou don't need a mill to cut aluminum. Dremel tool and a 1/8" coarse carbide burr will get you close (looks like an endmill but with diamond shaped points on it instead of continuous cutting edge like a twist drill). This will leave less work to be done with the file.A router table or drill press will allow better control, but you can do it freehand. Concentricity/runout matters, so just don't buy generic rotary tools. Dremel or Proxxon are the only things to bother with, IMO. A cheap one will do it, if you find the right pressure and rpm to avoid loosening your fillings, but the cutting efficiency will be very low, cuz it will only cut on one part of the bit.

author: thermistor-guy
author_rank: Frequent Contributor
timestamp: October 10, 2019, 01:50:15 am
content: Quote from: tkamiya on October 09, 2019, 02:24:01 amI make D-subminiature connector cut-outs on DIY test jigs. My tools are similar to yours: Dremel and accessories, files, Roper Whitney hand punch.My method for preventing cosmetic damage is to print the cut-outs, and other details, on adhesive A4 labels, 1:1, and stick the labels over the blank panels. Add masking tape over metal edges.You can include other details on the label, like critical dimensions, connector designation, pin 1 location, panel type and version number, design file name, and so on - very handy to have all the info you need right in front of you as you work.

author: beanflying
author_rank: Super Contributor
timestamp: October 10, 2019, 02:25:21 am
content: Sticky labels work really well in particular if it is a job you are likely to repeat. Due to the raised lip the nibbler wouldn't reach some of it so it was a combo nibble, saw and file. Catching the leavings as it was still attached to an otherwise working bit of HP'ness needed a little bodge. No smoke has escaped since so I think I caught all the bits.

author: BrianHG
author_rank: Super Contributor
timestamp: October 10, 2019, 03:02:59 am
content: Quote from: EEEnthusiast on October 09, 2019, 06:05:58 amIf you go this route, I have .dxf and gerber files for complete DB9 and DB25 connectors with adjacent mounting holes, DVI connectors, BNC connectors, RCA connectors, S-Video connectors, 2 Line LCD character displays, Square push buttons, LED holes, IR receiver holes, volume & rotary encoder controls and including complete front panel keypad & LCD displays with mounting PCBs & 3mm square fan grill openings.

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: October 12, 2019, 10:40:57 am
content: Bench top CNCs are the way to go these days. One time high cost, but they do a perfect job. You could use it to route wood, engrave on metal, cut any shape holes and much more. The drill bits are cheap too on Aliexpress. There are plenty of free software to control the CNC routers. You have to be careful though. The basic ones do not have limit switches but have some very powerful motors on them. You could damage your CNC machine and the work piece with improper programming.

author: beanflying
author_rank: Super Contributor
timestamp: October 12, 2019, 10:54:55 am
content: The question with CNC Square holes is are they Square or sort of square with rounded or dogbone corners? Even Lasers still have a beam diameter so a small curve in the corners.The time taken to set up for a one off job doing it by hand will win out for $/hole in most cases But if you have one they are a great tool. Must get onto rewiring my router and getting it into use

author: Yansi
author_rank: Super Contributor
timestamp: October 12, 2019, 11:01:13 am
content: I am yet to see how that garbage CNC mill copes with a 3mm steel rack case panel.I rather stick to my set of good ol files. Good enough for aluminium, good enough for steel racks.

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: October 12, 2019, 11:35:47 am
content: Quote from: Yansi on October 12, 2019, 11:01:13 amThose are some really great pieces of work. A bench top CNC cannot cut panels that large for sure. But it can surely cut thicker metal by going 0.1mm deep in one stroke and repeating over and over again. It takes a lot of time, but the machine does the job.

author: duak
author_rank: Super Contributor
timestamp: October 12, 2019, 06:25:23 pm
content: It's neither here nor there but back in the 70's & 80's I could get sheet metal punched and formed locally on a CNC turret punch. Here's a more modern example:http://www.vandf.co.uk/tooling/what-is-cnc-punching/Outside of my personal snack bracket though.Actually, back then it was an NC turret punch that read from paper tape and the vendor asked us if we could repair it. Turned out a 4 bit counter driven by a crystal oscillator had died. I really lucked out because the board had a bunch MSI chips on it and I didn't have a schematic.

author: james_s
author_rank: Super Contributor
timestamp: October 12, 2019, 06:28:59 pm
content: I use a nibbler tool generally. Other times I drill a round hole that takes out as much of the material as possible and then square it up with a file.

author: bson
author_rank: Unknown
timestamp: October 12, 2019, 07:23:47 pm
content: If it's for prototyping, the best IMO is to design them in a suitable CAD tool and either 3D print or mill out of acrylic. The same design files can then be used for manufacturing when you're happy. I find 3D printing is much easier than milling, for modest sizes. For a large panel milling is easier since it can be done in a single piece. Even for a 1-off DIY project I'd still do this and have someone mill me prototype panels once the 3D ones fit and seem right. You'll get a professional looking result you can show off and learn a useful and marketable skill.

author: coppercone2
author_rank: Super Contributor
timestamp: October 12, 2019, 11:00:42 pm
content: if its a big hole use a plasma cutter

author: james_s
author_rank: Super Contributor
timestamp: October 12, 2019, 11:16:40 pm
content: I still struggle to find an example of something that is 3D printed (on a hobby level machine) that doesn't look like crap. Milling out of acrylic can be ok but laser cut ABS is even nicer for panels IMO. I tend to build a fair number of one-offs though so hand machining aluminum panels is something I do fairly often. In the time it would take to draw it up in CAD I could just make the panel and when I only need one there's no advantage to having the CAD file.

author: beanflying
author_rank: Super Contributor
timestamp: October 13, 2019, 12:20:41 am
content: Quote from: james_s on October 12, 2019, 11:16:40 pmSurface finish on 3D Printing can be very good! This box picked at random came off my CR-10S over a year ago if I had needed holes added in the lid then a tweak to the Cad file and print another. Maybe not quite up to injection molded plastics but given the customization available for a low cost it is the most affordable prototyping or small production run option available.Time you had another look at 3D printing and where it now is not where it was 3+ years ago!

author: james_s
author_rank: Super Contributor
timestamp: October 13, 2019, 03:07:58 am
content: That's quite impressive, significantly better than what my friends with 3D printers generally achieve. One of my friends has printed up a lot of toys for his kid and a few marginally useful odds & ends, but I haven't been impressed by the amount of time spent screwing with the thing vs useful objects printed. I have high hopes for the future of 3D printing but so far the hobby machines have largely failed to live up to the hype.

author: beanflying
author_rank: Super Contributor
timestamp: October 13, 2019, 04:01:03 am
content: Without checking that zippy box is after 3 or 4 months of use with the printer still dead stock. It is printed on bare uber clean glass with no bed adhesive of any sort.I actually heaped some poo on printers only six months prior to buying my first one after having a long chat to another EE. Came home watched some videos and decided they were a simple way to get a result for not to many $ and that I was wrong about them.That said there is some jobs that are better done if you have access to them done by alternate means. Big flat slabs of fascia are a bad use for 3D Printing time so break out the LaserThe Ply is just a roughy and I will get a final one done in Aluminium given the proximity to heat, the other couple are actually going on the Laser with one being a 3d printed Laser hybrid.Use what gear you have or can afford and use it to it's best abilities is the point I guess.

author: Bassman59
author_rank: Super Contributor
timestamp: October 14, 2019, 05:59:19 pm
content: Quote from: beanflying on October 13, 2019, 12:20:41 amFor a recent project built into one of the Hammond extrusions, I 3D printed the front and back panels using the Makerbot 2 we have in the office. The print quality is "meh."Then there's the issue of labeling the jacks and buttons and such. For my first go-round I thought: decals! I took DXFs of the panels and added text to them and printed them out on a variety of sticker material, like all-weather shipping labels and such. It turns out that cutting out the holes with an X-Acto knife is no fun. So I bought a Cricut machine, which (despite the shitty software) does a pretty great job of printing the text and cutting out the holes on vinyl or sticky paper.Then I discovered thatnothingsticks to the 3D printer plastic. I tried prepping the surface with spray-paint primer and that helped but it's not as permanent as I'd like. I tried the 3M "90" spray adhesive and wow, that stuff is aggressive and not really easily controlled. Next up was another spray adhesive, E6000, which when combined with weighted clamping seems to be almost reasonable.If anyone has any ideas about adhesives that stick to 3D printed plastic and that are relatively easy to handle (such as a roll-on instead of a spray), I'm all ears!

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 14, 2019, 06:21:28 pm
content: Sanding first?

author: Bassman59
author_rank: Super Contributor
timestamp: October 14, 2019, 08:26:04 pm
content: Quote from: SiliconWizard on October 14, 2019, 06:21:28 pmTried that, wasn't much good. And the surface wasn't all that smooth prior to sanding, either, but I thought that scuffing it might help.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 14, 2019, 08:29:18 pm
content: Well, I suppose the right adhesive to use also depends on the type of plastics you used. Is that PLA or ABS?

author: max_torque
author_rank: Super Contributor
timestamp: October 14, 2019, 08:38:49 pm
content: As soon as you have to include any of your own time as a "cost" then just farming the whole thing out to your local Laser/Waterjet cutter suddenly looks like very good value indeed, especially if you value accuracy and repeatability...They tend to have minimum order quantities, but once over that value the cost is trivial.

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: October 16, 2019, 04:45:37 am
content: I have a suggestion for the front and the back panels if you are doing prototypes. Instead of cutting on the metal plates or 3D printing, you could use black acrylic sheets (2mm thick) and cut the shaped into them using a laser cutter. I have a low power laser CNC and use that to cut the acrylic panels. They come out very well and it is much faster to cut.

author: coppercone2
author_rank: Super Contributor
timestamp: October 16, 2019, 05:16:28 am
content: Quote from: Bassman59 on October 14, 2019, 05:59:19 pmsexycyborg on youtube has a video about gluing 3d printed parts + strength testing. none are very strong

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 09:25:01 am
content: I like to use a manual scroll saw.https://youtu.be/ED3ge9n-WPI?t=100https://manualidadesybellasartes.es/seguetas-marqueteria-4654

author: Gyro
author_rank: Super Contributor
timestamp: October 16, 2019, 10:54:03 am
content: Quote from: soldar on October 16, 2019, 09:25:01 amGood reminder. Actually electric scroll saws aren't ridiculously expensive these days and don't require as much dexterity. They have a much larger throat too.Of course the panel needs to be flat(ish) in order to manoeuvrer it across the table.A typical example:EDIT: The better ones have cast tables rather than sheet.

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 11:21:59 am
content: Quote from: Gyro on October 16, 2019, 10:54:03 amI could not find a picture of a manual scroll saw in English. Only electric ones.A good designer/engineer would cut all the holes first and then do the bending. I, on the other hand, first do the bending and folding and then the cutting holes. So manual saw it is.In any case, aluminum cuts like butter and I have carved out holes just with a knife. If it is a one time thing and you have time you can do anything with aluminum. It is only slightly harder than woodSome years ago I was given a Mini-ITX board but I had no case so I built one. I remember it took me forever and wondering if it was worth it. That case and computer have given me many years of service. OTOH, I have made things that I soon discarded and thought it had not been worth the trouble.

author: Gyro
author_rank: Super Contributor
timestamp: October 16, 2019, 11:36:12 am
content: Quote from: soldar on October 16, 2019, 11:21:59 amThe English term is fret saw or coping saw. Great tools in skilled hands! The jewellers' tool of choice (used with a little V shaped bench plate).

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 11:51:54 am
content: Quote from: Gyro on October 16, 2019, 11:36:12 amAnd I thought I could speak English! No wonder I could not find it.Every day I learn something new. When I was younger I would remember and retain what I learned. Now I tend to forget it. Maybe I will put a label on my fret saw.

author: beanflying
author_rank: Super Contributor
timestamp: October 16, 2019, 11:58:00 am
content: The issue becomes the blades on most coping saws and in particular electric scroll saws. I have owned an electric one for over 30 years and I don't use it on Aluminium ever. Balsa, Ply and some plastics is about it. You will do much better with the hardened teeth on a jigsaw blade than a scroll saw on Aluminum.

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 04:21:01 pm
content: Quote from: beanflying on October 16, 2019, 11:58:00 amI am having trouble parsing and understanding this. What's the issue?Obviously you need to choose the right blade. I have used a fret saw on aluminum without problem since forever. It allows cutting of all sorts of shapes without problem.

author: drussell
author_rank: Super Contributor
timestamp: October 16, 2019, 04:22:38 pm
content: Quote from: beanflying on October 16, 2019, 11:58:00 amHave you tried the abrasive blades?They are usually called things like "Carbide Blade" or "360° Cutting Saw Blade".A manual coping saw version with carbide or diamond grit is usually available inexpensively in the tile cutting section of your local hardware hut.You can also usually easily find a thicker model blade intended for use on a standard hacksaw handle for a few dollars if your panel is small enough to be able to use the typical hacksaw's limited reach. Eg. $3.73 Canadian available at Home Depot here, but online order only, apparently, but they do free "ship-to-store-for-pickup":https://www.homedepot.ca/product/qep-10-in-rod-carbide-saw-blade/1000164562

author: Bassman59
author_rank: Super Contributor
timestamp: October 16, 2019, 04:30:53 pm
content: Quote from: EEEnthusiast on October 16, 2019, 04:45:37 amI don't have access to a laser cutter!

author: Bassman59
author_rank: Super Contributor
timestamp: October 16, 2019, 04:35:56 pm
content: Quote from: soldar on October 16, 2019, 09:25:01 amI have a coping saw and I used it for a panel with only a few largish (1.5 cm) square holes, and it worked well. I also used it on plastic.My latest thing has a couple of long slots for a bargraph LED meter, and cutting that by hand in 1.5 mm aluminum doesn't seem like that much fun.

author: Bassman59
author_rank: Super Contributor
timestamp: October 16, 2019, 04:55:51 pm
content: Quote from: SiliconWizard on October 14, 2019, 08:29:18 pmIt's PLA.I did some searching and most of the results for "best adhesive for PLA" return things that assumes you want to glue two pieces of 3D-printed plastic together, not put a decal on a large-ish piece. There are various cyanoacrylate suggestions. Applying the glue to the panel could be annoying.To experiment, I took a piece of the printed plastic and sprayed it with two coats of primer paint, let it cure, then sprayed it with the E6000 adhesive and stuck my decal on that. Then I put some weight on the thing and let it sit for a day, and the sticker seems well stuck on.

author: Bassman59
author_rank: Super Contributor
timestamp: October 16, 2019, 05:00:32 pm
content: Quote from: max_torque on October 14, 2019, 08:38:49 pmFor a one-off prototype that's kinda expensive, but for making, say, 25, it's a no-brainer!I checked and Front Panel Express will make my panels for $32 each in qty 1, which is now sounding better and better. But I'd like to get my design correct before I spend real money, so 3D printing to at least get the holes in the right places is reasonable.I should revisit the idea of using aluminum printed circuit boards with black soldermask as panels.

author: dom0
author_rank: Super Contributor
timestamp: October 16, 2019, 05:04:24 pm
content: Quote from: beanflying on October 16, 2019, 11:58:00 amThere are scoll saw and coping saw blades that work for aluminium, but most blades are only meant for wood and plastics.

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 05:17:44 pm
content: Quote from: dom0 on October 16, 2019, 05:04:24 pmI guess I have the right ones because I have never had a problem sawing aluminum.Also, for straight longer cuts I have used a regular hacksaw blade.

author: Gyro
author_rank: Super Contributor
timestamp: October 16, 2019, 06:25:11 pm
content: Likewise. You need a finer pitch blade than you use for (soft)wood but that's about all. Jewellers use very similar blades to cut Sterling Silver.

author: tkamiya
author_rank: Super Contributor
timestamp: October 16, 2019, 06:45:09 pm
content: I wonder if there are any high speed dremel type tool that will withstand heavy-duty usage? I used a regular type for this particular time. Well... it got awfully hot. Also locking mechanism jammed so I had to take it apart and fix it. Maybe something like dentists use?

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 07:09:41 pm
content: Quote from: tkamiya on October 16, 2019, 06:45:09 pmI am thinking a compressed air "Dremel" would be tougher and last forever. Have you been to a dentist lately?

author: langwadt
author_rank: Super Contributor
timestamp: October 16, 2019, 07:10:18 pm
content: Quote from: Gyro on October 16, 2019, 06:25:11 pmhttps://youtu.be/Xo2GM2urd5I

author: tkamiya
author_rank: Super Contributor
timestamp: October 16, 2019, 07:46:13 pm
content: Quote from: soldar on October 16, 2019, 07:09:41 pmWooohooo! Great idea! I already have a smallish compressor. Thanks!

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 07:50:25 pm
content: Quote from: langwadt on October 16, 2019, 07:10:18 pmYes, in Spanish I have always called those saw blades "hair blades" because they are so thin. That arc is smaller and gives the user much better control. Mine has a wider arc with longer blade and more reach. It allows reach into deeper places but is also more cumbersome to use. Maybe I sould get a smaller one for finer work. In fact, I could use broken blades from the bigger one.

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 07:54:03 pm
content: Quote from: tkamiya on October 16, 2019, 07:46:13 pmI have a broken refrigerator and the intention of using the compressor to build myself a shop compressor. It'll be any year now.Compressed air tools have the advantage of being powerful and refrigerated by the expanding air.

author: dom0
author_rank: Super Contributor
timestamp: October 16, 2019, 08:02:22 pm
content: And being rather loud.

author: KL27x
author_rank: Super Contributor
timestamp: October 16, 2019, 08:10:57 pm
content: QuoteMy only Dremel is probably over 10 years old and still works like new.I use several Proxxon rotary tools, and the only one I killed was after a year or two of heavy use. Big side-loads in a router table, doing tasks that call for a real router. I've learned how to prevent even this. When the bearing starts to make funny noises, you have to stop using it and replace it right away before the commutators on the motor get worn out of whack. The Proxxon tools have their thin, slender neck at the cost of a stupidly thin ball bearing at that end. McMaster Carr sells them. They have only one model in this size, which is telling on how extreme a compromise it is.QuoteThe problem with air grinders is air supply. They're hogs. They have much lower inertia and suck massive air even when up to speed. They get their torque from sucking massive power all the time. You probably need at least 20 gallon tank and a decent compressor to use one, even a pencil grinder. A fridge compressor is high pressure, low output; not at all right to run an air grinder.I eventually upgraded my router table to take a trim router. And I bought a 1/8" collet for it, so I can still use all my rotary tool bits in it.*edit: I also occasionally use a trim router like a big dremel tool, using both carbide burrs and stone/hard points. With a carbide burr, it will eat plastic and aluminum, but you need a big hand to hold it.One curious thing I've found is that even the cheapest trim router you can find out of china runs true as any high money dremel or proxxon tool and will have a nicely balanced motor. Consumers seem to accept runout and buzz in cheap rotary tools, perhaps because they are still useful with a variety of tasks/bits. A router with any much runout would be fairly useless and perhaps even a safety issue. The balancing of the motor, which is the massive majority of the weight of the device, probably simply has to be done, and it seems that once that threshhold is crossed, it is perhaps not much more expensive to do the job, properly.

author: coppercone2
author_rank: Super Contributor
timestamp: October 16, 2019, 09:49:12 pm
content: don't you want a safety switch with 1/4 inch? I kind of feel like using a router free hand for metal is dangerous even if its overbuilt because of ergonomics. They are like a giant can

author: tautech
author_rank: Super Contributor
timestamp: October 16, 2019, 10:03:24 pm
content: Quote from: soldar on October 16, 2019, 11:51:54 amNote that a fret saw and coping saw are very similar but there's a distinct difference, fret saws have a very deep throat whereas coping saws have normally just ~120mm throats.

author: soldar
author_rank: Super Contributor
timestamp: October 16, 2019, 10:34:09 pm
content: Quote from: tautech on October 16, 2019, 10:03:24 pmOK, so what I have been using all along is a fret saw. I always called it a scroll saw because I thought a scroll saw was just the mechanical version of the manual thing.

author: tautech
author_rank: Super Contributor
timestamp: October 16, 2019, 10:42:12 pm
content: Quote from: soldar on October 16, 2019, 10:34:09 pmA fret saw is normally for shop and bench use whereas the much smaller coping saw is what carpenters had in their carry bags for finishing work onsite.Typically coping saws used 14 tpi blades that are still too coarse for thin alloy and won't touch steel.

author: beanflying
author_rank: Super Contributor
timestamp: October 16, 2019, 11:14:59 pm
content: Quote from: soldar on October 16, 2019, 04:21:01 pmAs per Tautechs posts blade pitch and hardness are the issue. My experience is the Coping saw blades and those found of the cheaper scroll saws are the issue. There are 'some' motorised saws that take a fret saw type blade that will be better but they are still not designed for working on 2-3mm Metal like we tend to use for fascias.

author: drussell
author_rank: Super Contributor
timestamp: October 17, 2019, 03:28:11 pm
content: Quote from: tkamiya on October 16, 2019, 06:45:09 pmAbsolutely. They are calleddie grinders.

author: Bassman59
author_rank: Super Contributor
timestamp: October 17, 2019, 05:11:17 pm
content: Quote from: drussell on October 17, 2019, 03:28:11 pmA die grinder is a fairly blunt instrument, not something you'd want to (or even be able to) use for putting switch/button holes in aluminum.

author: Bassman59
author_rank: Super Contributor
timestamp: October 17, 2019, 05:14:30 pm
content: Quote from: soldar on October 16, 2019, 07:54:03 pmI have an R2D2-sized air compressor in a room off my house. I use it with my air impact wrench (with car tires), for tire inflation, and with a ratchet wrench for outdoor assembly. (It was great for bolting together a gym set for the kid.) It's so fsckin' loud that I can't be in the room when it runs. And the tools themselves are loud.

author: Bassman59
author_rank: Super Contributor
timestamp: October 17, 2019, 05:16:54 pm
content: Quote from: KL27x on October 16, 2019, 08:10:57 pmI have an even older Dremel, maybe 25 years or so. I have a fantasy of using a Dremel-like tool for routing in 1.5 mm aluminum -- is that reasonable?

author: KL27x
author_rank: Super Contributor
timestamp: October 17, 2019, 05:29:36 pm
content: QuoteThe die grinder is the exacto knife of the steel shaping world. And it is used for porting aluminum engines to improve air flow, which involves shaping things smoothly and precisely. It would absolutely do stuff like this, using a carbide burr. They make burrs specifically for aluminum, as well. You'll have to finish the corners with a file, obviously. This is for the rough shaping.QuoteWell, a stubby die grinder isn't much different. It's always dangerous, and I suggest full face shield whenever using a burr in metal, cuz chips in your eye.https://www.amazon.com/Metabo-GE710-Compact-Variable-710-watt/dp/B00FDLB9OC/ref=sr_1_8?keywords=metabo+die+grinder&qid=1571332977&sr=8-8The problem with electric die grinders is they are expensive. There are cheap imports in the realm of the 25-30 dollar trim router, but they are junk with unbalanced motors.QuoteDunno. I've routed up to 5mm aluminum using trim router with an endmill, in a router table. That works good, but it's really slow, because you have to take shallow passes. IIRC, I was taking max 1/32"- 1/16th" cuts (but my router table has some compromises to the rigidity). This is one of the reasons I built a threaded incrementing fence, to make that find of adjustment quickly, and even down to 1/64th" for final pass. 1.5mm might be doable by a Dremel, but if you are imagining doing this free-hand, I suggest you stick with burrs.*edit: You can cut aluminum with any bit for wood. But if you route plexiglass or aluminum with a straight carbide cutter for wood, it doesn't cut as smoothly and it also leaves weird diagonal lines on the edge. Likewise, any drill bit or saw for wood will also cut aluminum. Even large forstner bits in a drill press; you just have to drill a pilot hole for the point, although some peeps just press a lot harder, lol. I use the router table on aluminum mostly for finishing and dimensioning, slots/grooves, and partial cavities. It's a lot like manual milling, but upside down. And with stop blocks instead of crank knobs; and you might have to include extra material for indexing against the table/fence which will be cut away when it's done. If you need tight tolerances, and esp parallel edges, a router table can get you there, eventually, you just have to want it bad enough, and you might have to add some parts along the way. Adjusting the Z-axis is the biggest pain, left on my table. I have a couple ideas on how to amend this, but I haven't had the need, yet.

author: tkamiya
author_rank: Super Contributor
timestamp: October 18, 2019, 01:36:23 am
content: I've seen my share of industrial accidents.... I've seen an arm fly off a lathe. I have a full face shield on every time I use dremel. The cutting blade may not have that much mass but the speed has enough to cause enough force to take out an eye or cause serious cuts.My compressor is pretty small and isn't too loud. I still don't want to be in the same space, so I have a long hose.

author: m3vuv
author_rank: Super Contributor
timestamp: October 18, 2019, 08:27:56 am
content: Quote from: tkamiya on October 18, 2019, 01:36:23 amdo lathes have arms?,ive never seen one with arms or legs come to think of it!!

author: beanflying
author_rank: Super Contributor
timestamp: October 18, 2019, 08:37:14 am
content: I have seen an arm put into a Lathe once it definitely didn't end well.Back when I had a real job I was pulled up by the companies MD over why I wasn't wearing a tie when I came back into the office on several occasions after visiting clients. The business involved Pumps, Motors and Gearboxes clearly his MBA following the fancy private school didn't give him all of the answers after all.

author: tkamiya
author_rank: Super Contributor
timestamp: October 18, 2019, 09:12:21 am
content: do lathes have arms?,ive never seen one with arms or legs come to think of it!!Do I need to be graphic? Lathe doesn't have arms but the operator does/did.

author: dom0
author_rank: Super Contributor
timestamp: October 18, 2019, 05:18:32 pm
content: Weeeeeeeeeeeeee

author: coppercone2
author_rank: Super Contributor
timestamp: October 20, 2019, 02:37:56 am
content: you can use a dremel to route thin aluminum of 1.5mm but you need to make a fixture so it does not vibrate (i.e. stiffen it with some steel behind it) and very carefully feed it to a carbide burr, it tends to 'bounce' around in the hole.if its something like a angle beam, then you can just put it in a vise and its stiff enough. but if its a sheetLike put it in a vise and clamp 2 steel bars behind the aluminum close to where you are cutting so it does not vibrate too muchbut I don't see you making nice squares, it will still require some filing (I recommend a special aluminum file)

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: March 02, 2020, 06:44:16 am
content: Finally I was able to get my CNC milling machine/router to work. I had assembled it almost a year ago but left it in the corner as I got busy with other things.Yesterday I cut out a rectangle hole 10x5mm on a 2mm thick aluminium panel. The first attempt was a fail as I was learning to set the speed, drill depth, correct bit size etc.The 2nd one came out decent. Attaching a pic.The CNC I have used is the one belowhttps://www.aliexpress.com/item/32836161266.html?spm=a2g0s.9042311.0.0.5a964c4dWT7bXvI used LibreCad to make the hole dxfThen use DXF2GCODE Tool to convert that to GCodes.Then GRBL Controller software running on Windows is used to send the GCodes to the CNC machine.I used a 1mm milling bit bought from aliexpress for the tooling.Few care-abouts==========Just ensure that the spindle is rotating fast enough (6000 rpm+) when cutting on metal with small milling bits.The XY movement rate was set to 120 mm/min (about 2mm per second).The Z movment is set to 0.05mm per iteration. So it takes about 40 iterations to complete this cut.Note : I have no affiliation with AliExpress or any CNC makers.

author: wizard69
author_rank: Super Contributor
timestamp: March 02, 2020, 10:57:19 am
content: About that mill, training shouldn't inhibit your ability to learn to use a milling machine. The real problem with milling machines is the expense. This makes me wonder if you have a makers space near by that you can join. The ability to properly machine something opens up all sorts of possibilities with respect to your hobbies.For ideas that don't involve milling machines I have a few to list. Realize though you need to check to see if they are suitable for 3mm thick aluminum.You can buy powered nibblers for electric drills with a bit more capacity. Example:https://www.amazon.com/dp/B017JRJUI4/ref=sspa_dk_detail_2?psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFFU1NCWDM3MU9MSUgmZW5jcnlwdGVkSWQ9QTEwNDAxMDEySE41RUExNkY4RVUzJmVuY3J5cHRlZEFkSWQ9QTA4MDA5NDcxSDBCVjFRUzhTOU9NJndpZGdldE5hbWU9c3BfZGV0YWlsMiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=A jig saw can do the job if the item to be mounted has a flange to cover the ragged edge.Actually your drill and file method it tried and true. The trick here is having the right files. A good vise or other method of clamping the work down is needed. Being able to clamp the panels down is key to getting good results with hand tools.Quote from: tkamiya on October 09, 2019, 03:43:04 amIt has been that way in the DiY world forever. It is only recently that low cost alternative methods have turned up. Even in industry we sometimes have to resort to this approach.QuoteIt might pay to make friends with an electrician, especially one that does machine controls.

author: wizard69
author_rank: Super Contributor
timestamp: March 02, 2020, 11:51:23 am
content: Some more general tips for working with aluminum:Lubrication helps! WD40 is surprisingly good when it comes to aluminum machining. It can help greatly when using powered tools but also helps for manual work.Just about any tool used for wood working will machine aluminum. Table saws are regularly used to cut aluminum stock to dimension/ There is considerable noise though. Do make sure your approach is safe.I've used a hand held router with burrs usually associated with die grinders to machine both steel and aluminum. The spindle speed is about the same so you get similar removal rates. Frankly with two hands on the router and the work piece clamped you get better control. Even better is to use fencing in the same way you would for routing wood. The more control the better. Usually I do this to "clean up" stuff that was rough cut via other methods.If the visuals allow you can avoid the hand work of cleaning up the corners of cutout done with rotary tools by over traveling on one axis half the tool diameter. This can save a lot of time be it in a production setting or simply something you are doing by hand.A 4.5" right angle grinder can work miracles in the right hands. You can also screw things up real quick. However they can make real quick roughed out rectangular cut outs.When drilling sheet metal use drill bits designed for such. Stepped drills used by electricians are idealMachinist tools help greatly. Consider deburring tools from Noga and others. Triangular scrapers are very useful. Layout tools cna be of huge help, the square, compass, scribers, even layout ink, can make it far easier to create a good looking panel. These tools will not do your cutting but they can lead to a far nice end product./li]

author: langwadt
author_rank: Super Contributor
timestamp: March 02, 2020, 11:56:27 am
content: Quote from: wizard69 on March 02, 2020, 11:51:23 amethanol is a much better and it doesn't smell or leaves a mess

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: March 02, 2020, 02:14:11 pm
content: Quote from: langwadt on March 02, 2020, 11:56:27 amI'm wondering if ethanol fumes can catch fire due to high temperature caused by the milling. Is it really safe to use ethanol in such applications?

author: langwadt
author_rank: Super Contributor
timestamp: March 02, 2020, 02:39:43 pm
content: Quote from: EEEnthusiast on March 02, 2020, 02:14:11 pmmilling aluminum isn't very high temperature and it is only tiny amounts of ethanol, so I don't see it being anymore or less safe than using wd40

author: beanflying
author_rank: Super Contributor
timestamp: March 03, 2020, 12:20:48 am
content: Still better to move to something with a lower flash point just in case. Mineral Oil (Baby Oil) or Kerosene (plenty of others but these are easy to get) would be safer options. It would need a wipe over post Milling but your eyebrows will still be in place.I still like the Nibbler for odd awkward jobs, iron filings in the PC build wouldn't work to well

author: Renate
author_rank: Super Contributor
timestamp: March 04, 2020, 12:28:47 am
content: Some of the Dremel tools are ok for steel, but they are lousy for aluminum.I bought a few expensive 1/8" 2 flute fancy coated end mills from McMaster.I had to make a jig to cut radiuses on some 1/4" x 1" aluminum.Dremels are not too good a choice as you really can't do constant speed, only constant power.Still, if you control the speed (and the chatter) they can be handy.Slightly off subject, plastic drills! I love them!No, they are not plastic, they are steel.They have a 0° rake so they don't dive through your little plastic box leaving a mangled hole like a butterfly.Don't use them for anything but plastic.Hmm, I can't even find the brand I bought.Here's another brand:https://www.tapplastics.com/product/supplies_tools/plastic_tools_supplies/tap_plasdrill_bits/161

author: beanflying
author_rank: Super Contributor
timestamp: March 04, 2020, 12:49:40 am
content: Interesting I didn't know you could by zero rake drillsQuick check on Amazon turned up this setNorseman Drill SetNow do I 'need' as small set and where are the Metric onesOn Rake angle I have been looking at getting a zero rake Saw blade for my tracksaw for Acrylic and Aluminium for a T Slot build I have coming up but I am making do with the thin kerf Plywood blade for breaking down Acrylic sheets for my Laser and doesn't chip.

author: tautech
author_rank: Super Contributor
timestamp: March 04, 2020, 12:55:58 am
content: Quote from: beanflying on March 04, 2020, 12:49:40 amCrosscut blades have entirely different rake to ripping or combo blades....go down that rabbit hole.

author: beanflying
author_rank: Super Contributor
timestamp: March 04, 2020, 01:03:20 am
content: Quote from: tautech on March 04, 2020, 12:55:58 amI have both already the saw came with a Rip/Combo blade and I added one of thesehttps://www.bunnings.com.au/diablo-165mm-6-5-40-teeth-fine-finish-cordless-circular-saw-blade_p6370899for Ply and Panel working great so far only runs a shallow rake.

author: tautech
author_rank: Super Contributor
timestamp: March 04, 2020, 01:24:24 am
content: Quote from: beanflying on March 04, 2020, 01:03:20 amYes because the depth of cut and therefore control is done with a depth gauge instead of a tooth rake best suited to the material or the job. Horses for courses.