Cutting project box, Laser, milling or what are the options  - Page 1
Forum section: electronics / beginners

author: sairfan1
author_rank: Frequent Contributor
timestamp: June 30, 2020, 07:18:47 pm
content: I bought some project boxes (enclosure) and need to cut holes of different sizes, i never imagined it could be that hard and time taking, i was trying to cut a circular hole by first drilling then grinding.Does anyone knows the best way to cut holes in different shapes like circle, rectangle etc. I'm thinking to buy a small CNC i saw some on Aliexpress.I also want to know if those 7w, 15w laser would work? i understand those are too weak but is it possible if we repeatedly try to cut with laser? for example this onehttps://www.aliexpress.com/item/4001118629952.html?spm=a2g0o.cart.0.0.148f3c00idqrp8&mp=1

author: themadhippy
author_rank: Super Contributor
timestamp: June 30, 2020, 07:48:38 pm
content: Ive a selection of drill bits, holesaws ,and punches.The size of hole and the material dictate which i use,for plastic, drills and holesaws work best,don't force them or you risk cracking brittle plastics.On metal, drills and holesaws also work but can leave a ragged edge,for a nice round hole not much beats a q punch.One very useful tool is a stepped drill.If i need non round holes its either out with the dremel or drill the largest circular hole that fits and start filing.

author: Benta
author_rank: Super Contributor
timestamp: June 30, 2020, 10:01:54 pm
content: What tools do you have? Ranging from perfect to hopeless:- CNC Mill- Mill- Drill press- Drilling machine with stand- Drilling machine- Chisel and hammer- Screwdriver- Flint axeJokes aside, only the first four apply. So what's in your workshop?

author: Mechatrommer
author_rank: Super Contributor
timestamp: June 30, 2020, 10:17:26 pm
content: Quote from: Benta on June 30, 2020, 10:01:54 pmdo not underestimate the power of the dark side...

author: sairfan1
author_rank: Frequent Contributor
timestamp: July 01, 2020, 12:26:04 am
content: sorry i was not enough clear, i have drills, and tried with it, what i was trying to say, i want to know, how effective it is to use CNC or 7w/15w Laser

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 01, 2020, 12:48:35 am
content: Quote from: sairfan1 on July 01, 2020, 12:26:04 am15w laser? useless than flint axe... CNC? it depends on what price...or this...

author: ledtester
author_rank: Super Contributor
timestamp: July 01, 2020, 04:55:38 am
content: Depending on the thickness of the plastic, you could use a nibbler tool:https://en.wikipedia.org/wiki/NibblerYou still have to create the initial hole for the tool, but after that you have good control over what it removes.

author: ledtester
author_rank: Super Contributor
timestamp: July 01, 2020, 05:10:35 am
content: Here's another idea -- 3d print a jig for a Dremel:

author: JustMeHere
author_rank: Frequent Contributor
timestamp: July 01, 2020, 05:18:04 am
content: Minimill like this:https://littlemachineshop.com/products/product_view.php?ProductID=4962&Source=GoogleMerchant&device=c&keyword=&utm_medium=referral&gclid=EAIaIQobChMI7fX7xaar6gIVxtSzCh3Dgw4mEAQYASABEgK25PD_BwE

author: sairfan1
author_rank: Frequent Contributor
timestamp: July 02, 2020, 07:49:09 pm
content: It looks me like milling with cnc is the best option, what do you mean by capable cnc? Chinese cnc are not well accurate? I have licensed cnc driver from planetcnc, is it enough if i buy mechanical part from China?I also want to know what kind of bits would be ideal to mill holes in plastic boxes

author: Renate
author_rank: Super Contributor
timestamp: July 02, 2020, 09:13:47 pm
content: The first thing about laser is that you shouldn't cut anything that has chlorine in the formula (like PVC).Besides the chlorine being bad for you, it's not good for the optics and mechanics.I used to () have ready access to a laser cutter.I used to lay out my boxes in CAD then cut out a template out of some scrap acrylic.I'd usually just make all the holes 1/16", drill the pilot, then drill the larger size.Also, I can heartily recommend "plastic drills".Yes, they are steel, but they have zero "rake" so they don't "dive" through your box leaving a ragged hole.Indispensible for acryclic but great even for plastic boxes

author: Benta
author_rank: Super Contributor
timestamp: July 02, 2020, 10:22:04 pm
content: Quote from: JustMeHere on July 01, 2020, 05:18:04 amNO!Money spent on that so called "machine" is better spent on contacting a local machine shop and letting them do the job.

author: langwadt
author_rank: Super Contributor
timestamp: July 02, 2020, 11:33:08 pm
content: Quote from: Benta on July 02, 2020, 10:22:04 pmit'll be fine for small projects especially in plastic, and you don't get much done at a machine shop for $700

author: thm_w
author_rank: Super Contributor
timestamp: July 03, 2020, 12:29:00 am
content: If we are just talking about plastic then one of the cheap CNC routers should be better, for half the price. The Sieg is manual so its not a simple operation to machine a specific circle diameter. Hell even a square you'd have to do some math. Of course if you are interested in machining metal and other things it can make sense.Quote from: langwadt on July 02, 2020, 11:33:08 pmYou can get a lot of laser cut acrylic or 3D printed replacement covers for $700. Wouldn't match the case though.

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 03, 2020, 03:38:37 am
content: Quote from: thm_w on July 03, 2020, 12:29:00 amtalking about 3d printing. for small build, recently i got Elegoo Mars MSLA Printer for ~$400 (incl shipipng from USA), i think there are bigger siblings, but more expensive. the precision is unprecendented to my Prusa Clone PLA/ABS extrusion printer. i can get the sense of difference by adjusting my custom designed enclosure to 0.1mm accuracy with minimal touch up to output product. with normal plastic 3d printer, i can adjust to 0.3mm and i still cant get it right, needs tiresome sanding and redrilling etc. with this machine you can design any kind of shape even to your cat's heart content, not stuck to the classical rectangular box, and i mean it, any kind even thats near impossible or envied by 5-7 figures priced injection molding industry. it took me less than a week after the MSLA arrived to do 3-4 iterations of enclosure design (protrutions in all 3 axis that probably needs 4 - 10 mold blocks, go figure the price) until i'm satified to move to the next stage.

author: Jwillis
author_rank: Super Contributor
timestamp: July 03, 2020, 07:13:21 am
content: Quote from: JustMeHere on July 01, 2020, 05:18:04 amI have a friend that has one like this and he mills brass , aluminum and mild steel . It does a fairly decent job too . Plastic would be a breeze.The problem I see with the CNC mills is the tool bit rotates at a very high speed and could gum up with melted plastic if forced to hard . I encounter that a lot with Dremels. Lasers and plastic I would figure there would be a fair bit of toxic smoke but I could be wrong. I've used a nibbler for sheet metal but not on plastic . Most of the time I use a Dremel multi max MM20 oscillating saw for plastics.https://www.dremel.com/en_US/products/-/show-product/tools/mm20-05-multi-maxHandy tool which even works on copper clad .

author: Benta
author_rank: Super Contributor
timestamp: July 03, 2020, 04:20:47 pm
content: Quote from: Jwillis on July 03, 2020, 07:13:21 amThe tool bit only rotates at at high speed if you program it like that. A good CNC setup has full control over tool rpms.

author: wizard69
author_rank: Super Contributor
timestamp: July 03, 2020, 08:31:32 pm
content: To answer the specific questions:A CNC milling machine can be very effective but has shortcomings that might be a problem. The big one is that you don't get squared up corners (round cutter in a square hole) which can require rework depending upon how critical of a fit you need.The laser would be next to useless in most metals. A commercial scale laser of a couple of hundred of watts might do. The question is how thick is the metal to be cut. If plastics the question is also thickness but also the type of plastic.You might want to look into desktop water jet machines if you really want a CNCmethod of cutting these materials.I guess the real question here is what problems are you having? People have been doing project boxes for a long time using hand tools. As a result you might not have the right tools or simply don't know the methods involved.One gotcha that non machinist may not know is that many brasses and plastics should not be drilled with the standard edge on twist drills. Basically you have to change the angle of the cutting lips.Quote from: sairfan1 on July 01, 2020, 12:26:04 am

author: ledtester
author_rank: Super Contributor
timestamp: July 04, 2020, 01:07:50 am
content: Two videos with some very helpful ideas:NFM - How to make professional looking front panelshttps://youtu.be/lgJ4Z_qLLdUBen Heck - Creative Case Hacks: No 3D Printer Required!https://youtu.be/grG3EVPg1vI

author: JustMeHere
author_rank: Frequent Contributor
timestamp: July 07, 2020, 03:06:18 am
content: Quote from: Benta on July 02, 2020, 10:22:04 pmThere are cheaper versions of this mill. Look at Harbor Freight. This mill (and the other copies of it) can be converted into a CNC machine as there are several kits available for upgrading it.

author: Microcheap
author_rank: Frequent Contributor
timestamp: July 07, 2020, 04:40:47 am
content: To drill my enclosures I normally start by doing a template of the holes using Inkscape or some CAD tool like SolidWorks, print that in a sheet of paper and stick it to the box to use as a reference.Then, I simply use a cheap cordless drill that I got from Lidl with a combination of step drills (ie) to make holes of different sizes. A rotary tool (Dremel clone) with cutting discs to open slots. A set of tap drill bits to make threads (ie) and a set of jewellery files to finish and make small adjustments. A exacto knife is very useful as well.To finish, I make an art work of the front panel in Inkscape, print it in adhesive paper and apply to the box, this will cover any imperfection and give a nice look. With patience and some practice you can get very good results.I just got a 3D printer, so I hope I will be able to print customized enclosures for my project from now on.

author: Bassman59
author_rank: Super Contributor
timestamp: July 07, 2020, 06:08:19 am
content: Quote from: JustMeHere on July 07, 2020, 03:06:18 amHarbor Fright charges the same $699 for this mill, and it’s their least-expensive mill.

author: SmokedComponent
author_rank: Regular Contributor
timestamp: July 07, 2020, 10:46:12 am
content: Plastic is easy (and messy) to do it by hand - for one-off projects.I have a nice set of files, square, round, big, small, you name it. Some practice and even more patience and you get the job done without scoring or overdoing anything. I use other tools like drill, dremel and even big screwdriver, as needed, to make initial hole and then go from there.

author: dcbrown73
author_rank: Regular Contributor
timestamp: July 07, 2020, 02:21:11 pm
content: Milling the sides of project boxes becomes an issue. Especially with some types of boxes that come a part. (the image below doesn't show it, but the bottom left/right sides of the box are connected and the entire box works like a clam shell. Meaning, the front (and sides) do not have support and makes milling difficult to say the least.I ended up just using a dremil (well, WEN knockoff) with a cutting blade.The cuts here are a bit crude, but that's because it was my first attempt. When everything installed, it's actually pretty clean and you don't see the dirty cuts.It's a current limitor for my bench. I don't have the dual 60w light sockets installed yet in this picture.

author: rdl
author_rank: Super Contributor
timestamp: July 07, 2020, 08:03:46 pm
content: Something to keep in mind. A lot of enclosures/boxes are of the design where two basically U-shaped parts fit together. One piece is the top and sides and the other forms the front and back panels and the bottom. These are a real pain to work with if you need anything more complicated than a few simple holes. I never use this type anymore. The type I think is best is usually called clam shell. Top bottom and sides are formed from two parts. The front and rear panels are separate pieces, and most importantly, they are flat. This makes them very easy to work on.

author: tkamiya
author_rank: Super Contributor
timestamp: July 07, 2020, 10:55:02 pm
content: I have a small drill press. Rest is all hand tools and small electric tools. Dremel comes in very handy, but mine is not that sturdy. Chuck jams and motor stalls. With that and enough Bandaids, I get my job done.

author: Renate
author_rank: Super Contributor
timestamp: July 08, 2020, 11:32:47 pm
content: Dremel is overpriced, the variable control is nowhere in the direction of constant speed.The "slowest" settings stall if you try to cut a piece of white bread.Some other brands are even worse.

author: tkamiya
author_rank: Super Contributor
timestamp: July 08, 2020, 11:58:57 pm
content: Yes, on all points. I can't disagree more. Still, it's the biggest helper in getting my job done. You forgot to complain about that awful chuck. I got it stuck more than few times.