Post by thread:Openings in Project boxes [OT]

"C'Mon, Bill. Get a PIC-based CNC X-Y table going, mount the mototool above it, and move the case piece under PIC control to precisely route the desired hole." <VBG> Well, manually... A nibbler is a good tool for rectangular openings. You do have to pay a little attention (the "Bite" it takes isn't square - more dovetail shaped - Works though.) It'll happily chew on YOU, though, so watch the sharp edges. Radio Shack has 'em for ~ $10.00. Another way to cut holes to shape is to use a hot knife (Suggestion: Use a nice vacuum cleaner or air pump to suck the fumes generated, and direct 'em OUTSIDE. Your nose will appreciate your consideration!) Braze or silver solder an Exacto knife blade onto a cheap Radio Shack soldering iron's tip, and you can cut & cauterize easily - Good idea to have a safe place to set this! Also can set a crummy old paring knife on a burner, let it get hot, use it to cut (turn the kitchen vent fan on - Hope it vents outdoors!) You can make a rectangular shaped blade, heat it, and cut the entire hole at once. (Do usually need to clean up with a small file or emery board or sharp knife, after hot knifing. So cut the hole a little small, then scrape or sand of file to fit.) Another: Cannot remember the name of the tool, basically you drag a little "planer" blade (quite narrow and very sharp!) along where you want to cut into the plastic. Could also use a "gouge" but those tend to be dangerous <G> A "drag planer" (?) dragged alongside a metal ruler (for the first cut or two), can do a pretty good job of cutting a narrow slot. The tool I'm talking about looks just sorta like a 1/32" wide curled-up planer blade. There are dental picks that are similar. Another tool that does a similar job - there's a little file that's just sharp on the edge of a little piece of itself (Clipping a little piece off the edge of a hacksaw blade and brazing/silver soldering/spot welding it to a handle could work fairly well, use a fine-toothed blade though.) Sorta saw down into the piece, one slice at a time. Use a metal ruler again, for the first few cuts at least. "Riffle Files" are a GOOD tool for this sort of thing. Boeing Surplus is a good place to look for these, if you're in the Seattle area. Many good supply places (Enco, Small Tools, ...) out there on the Web. Mark Bill Pierce wrote: {Quote hidden}> I just wanted to say first that this is a great list. Everything is > informative or interesting. Anyway on to my question. > > I have a product that goes into a Serpac box. I have a few round holes for > switches that are easy to drill. I also have two rectangular openings for > the 9V power supply and for a terminal block.. > > I am cutting the openings with a Dremel tool now but it doesn't look real > good and I can't seem to get any accuracy. What is everyone else doing to > make openings in off the shelf enclosures. > > Thanks for any advice > > Bill

If you need to chunk them out a lot at a time real fast you can make a custom punch and set it up in an arbor press. For my app it's not a real big deal to take 15 minutes with my nibbler and template method. Bill Pierce wrote: {Quote hidden}> I just wanted to say first that this is a great list. Everything is > informative or interesting. Anyway on to my question. > > I have a product that goes into a Serpac box. I have a few round holes for > switches that are easy to drill. I also have two rectangular openings for > the 9V power supply and for a terminal block.. > > I am cutting the openings with a Dremel tool now but it doesn't look real > good and I can't seem to get any accuracy. What is everyone else doing to > make openings in off the shelf enclosures. > > Thanks for any advice > > Bill > ________________________________________________________________________ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com

I use a milling machine when I can. I have one project that uses a small square hole that needs sharp corners. I made a template out of 1/8: aluminum that fits into the inner recess of the enclosure. I press it in, drill a 3/8" hole in the center of the square hole, cut to the aluminum template with a nibbler(available at Radio Shack for about $10.00), and do a little finish work with a needle file if needed. Bill Pierce wrote: {Quote hidden}> I just wanted to say first that this is a great list. Everything is > informative or interesting. Anyway on to my question. > > I have a product that goes into a Serpac box. I have a few round holes for > switches that are easy to drill. I also have two rectangular openings for > the 9V power supply and for a terminal block.. > > I am cutting the openings with a Dremel tool now but it doesn't look real > good and I can't seem to get any accuracy. What is everyone else doing to > make openings in off the shelf enclosures. > > Thanks for any advice > > Bill > ________________________________________________________________________ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com

Hi, If you need to make 10-20 then you can work by hand. For larger numbers, contact a machine shop to make a break-out stencil for all non-round holes (2-piece with screw). For really large numbers a machine+jig will be used (with stencils). Depending on the plastic used and shape of the hole, it is possible to use a 'hot' stencil. This 'stinks' but is is less expensive than the real mechanical stencil. Holes made with hot stencils may need deburring. There is also a way to make a partial hot stencil and then break out the outlined port. This requires a two-sided jig for the stencil and at least a hand press, but it is easy to set up (low tooling cost). The greatest advantage is that the part to be removed does not clog the machine so productivity is high. Stencils for most standard connectors are available ready made, f.ex. from Allied and Mouser I think. Figure $80 per ready made stencil (not including the press). Stencils with simple shapes (square, rectangle) are relatively cheap from a machine shop. For handwork in ones, a drill and a jeweller's saw is all you really need. For more gross work you can use needle files to work the round holes into required shapes. Just practice until you get good (perhaps using scrap boxes). I use the hand drill and jeweller's saw for ones. The jeweller's saw cuts so accurately and finely in plastic and aluminium that you can't really tell whether the part is coming from a factory CNC line or from a prototype lab. It helps to span the blade short for precision work. There is an accessory for the Dremel tool that allows you to do some more accurate work. It uses a manual XY table under a standard drill press holding the tool. You will need to make a wooden jig to hold the box in the xy table. If you already have the drill press, look for the *matching* (beware !) XY table in a Dremel catalog. hope this helps, Peter {Quote hidden}>I just wanted to say first that this is a great list. Everything is >informative or interesting. Anyway on to my question. > >I have a product that goes into a Serpac box. I have a few round holes for >switches that are easy to drill. I also have two rectangular openings for >the 9V power supply and for a terminal block.. > >I am cutting the openings with a Dremel tool now but it doesn't look real >good and I can't seem to get any accuracy. What is everyone else doing to >make openings in off the shelf enclosures. > >Thanks for any advice > >Bill

In a message dated 5/13/00 6:52:04 PM Eastern Daylight Time, .....plpKILLspam@spam@ACTCOM.CO.IL writes: << Hi, If you need to make 10-20 then you can work by hand. For larger numbers, contact a machine shop to make a break-out stencil for all non-round holes (2-piece with screw). For really large numbers a machine+jig will be used (with stencils). Depending on the plastic used and shape of the hole, it is possible to use a 'hot' stencil. This 'stinks' but is is less expensive than the real mechanical stencil. Holes made with hot stencils may need deburring. There is also a way to make a partial hot stencil and then break out the outlined port. This requires a two-sided jig for the stencil and at least a hand press, but it is easy to set up (low tooling cost). The greatest advantage is that the part to be removed does not clog the machine so productivity is high. Stencils for most standard connectors are available ready made, f.ex. from Allied and Mouser I think. Figure $80 per ready made stencil (not including the press). Stencils with simple shapes (square, rectangle) are relatively cheap from a machine shop. For handwork in ones, a drill and a jeweller's saw is all you really need. For more gross work you can use needle files to work the round holes into required shapes. Just practice until you get good (perhaps using scrap boxes). I use the hand drill and jeweller's saw for ones. The jeweller's saw cuts so accurately and finely in plastic and aluminium that you can't really tell whether the part is coming from a factory CNC line or from a prototype lab. It helps to span the blade short for precision work. There is an accessory for the Dremel tool that allows you to do some more accurate work. It uses a manual XY table under a standard drill press holding the tool. You will need to make a wooden jig to hold the box in the xy table. If you already have the drill press, look for the *matching* (beware !) XY table in a Dremel catalog. hope this helps, Peter >I just wanted to say first that this is a great list. Everything is >informative or interesting. Anyway on to my question. > >I have a product that goes into a Serpac box. I have a few round holes for >switches that are easy to drill. I also have two rectangular openings for >the 9V power supply and for a terminal block.. > >I am cutting the openings with a Dremel tool now but it doesn't look real >good and I can't seem to get any accuracy. What is everyone else doing to >make openings in off the shelf enclosures. > >Thanks for any advice > >Bill >> Thanks Peter, I learned a good bit from what you said here. I would like to mention, however, that he may also want to consider having Serpac mill the cutouts. I have 100 of their A-27 cases on order where they are milling the cutouts and they are quite reasonable and, typically, have about 3 week turnaround time. Maybe Bill needs to tell us what kind of quantity he is talking about. Hope this helps and thanks for all the info. Max

If you are REALLY interested in a great way to drill your own PCBs and fabricate holes and slots and any shape desired in panels and cases, you should take a few minutes and check out: http://www.sherline.com In particular, take a look at the Sherline vertical mill: #5000-CNC (inch version): Standard vertical mill w/ 10" base plus 3 stepper motor mounts (Metric P/N 5100-CNC) $750.00 This has the stepper motor mountings so you can put three stepper motors on and have yourself a PIC numerically controlled drill press/milling machine. A quick excerpt from the data available at the website: ****************** Beginning of Sherline text. The main difference between a lathe and a mill is that on a lathe, the work turns and the cutting tool is stationary, while on a mill, the tool turns and the work is stationary. Because of the tremendous number of operations that can be performed on a vertical mill, it is commonly regarded as the most important machine in the modern machine shop... the work horse of the industry. At first glance a vertical mill looks similar to a drill press, but there are some important differences, such as a spindle that can take side-loads as well as end loads and an accurate method of moving the work in relation to the spindle on all three axes. The SHERLINE MILLING MACHINES can perform all of the tasks and operations that a large commercial machine can perform. Operations such as milling, fly cutting, precision drilling, and boring are all routine tasks for the SHERLINE. Because the tool turns rather than the work, much larger parts may be worked on in a mill (these parts need not be round). The work is securely held, thus extremely accurate hole patterns can be drilled or bored using the SHERLINE vertical mill. The longer "X-axis" throw also increases the machine's versatility over that of the Lathe with the vertical milling column attachment. It is an extremely rigid, accurate tool which accomplishes tough machining jobs with ease. Model 5000 (5100) The Model 5000 (5100 metric) features a solid 10" (254mm) aluminum base, precision machined dovetailed slides with adjustable gibs, permanently lubricated spindle bearings, adjustable pre-load anti-backlash feed screws on "X" and "Y" axes, two 1-5/8" (41mm) laser engraved aluminum handwheels, one 2-1/2" (63mm) laser engraved handwheel with thrust bearings, and many other features found only on the best commercial machines. This machine along with a SHERLINE LATHE will enable you to complete almost any job in your own machine shop. *************** end of Sherline text These can be controlled both manually and by stepper motor. For a one-off you would use manual control. If you have a lot of identical pieces to be done, then you make up a jig to hold the case/panel in place and produce a control file that tells the CNC machine how to make the shapes you want cut. You get identical results each time. Fr. Tom McGahee {Original Message removed}

Hi all, To add my two cents worth to the discussion, I use the following method extensively for small quantities:- - Draw a template for your box cutouts and holes etc on your PC. - Save it to disk! - Print it out on paper, one copy for each box you are making. - Glue it to your plastic box using a glue stick. This template negates the need to measure and mark out anything! - Use drill bits with the cutting edge ground back to vertical to drill all your round holes - works great. - For square holes (eg LCD windows) I use about a 4mm drill in a drill press and use it like a router bit. With a bit of practice you can do this amazingly fast and still keep well within the lines printed on your template. - Finish off the square holes by filing to the edge of the lines on your template. A clever design makes sure that a label covers all your not so perfect handwork. - Put the box in warm water with a little detergent to remove the paper template and glue. Brent Brown Electronic Design Solutions 16 English Street Hamilton, New Zealand Ph/fax: +64 7 849 0069 Mobile: 025 334 069 eMail: @spam@brent.brownKILLspamclear.net.nz

I have one and I use it more than my 30" table Rockwell Mill. Thomas McGahee wrote: {Quote hidden}> If you are REALLY interested in a great way to drill your own > PCBs and fabricate holes and slots and any shape desired in > panels and cases, you should take a few minutes and check out: > http://www.sherline.com > In particular, take a look at the Sherline vertical mill: > #5000-CNC (inch version): > Standard vertical mill w/ 10" base plus 3 stepper motor mounts > (Metric P/N 5100-CNC) > $750.00 > > This has the stepper motor mountings so you can put three > stepper motors on and have yourself a PIC numerically controlled > drill press/milling machine. A quick excerpt from the data available > at the website: > > ****************** Beginning of Sherline text. > > The main difference between a lathe and a mill is that on a lathe, the work > turns and the cutting tool is stationary, while on a mill, the tool turns and > the work is stationary. Because of the tremendous number of operations that can > be performed on a vertical mill, it is commonly regarded as the most important > machine in the modern machine shop... the work horse of the industry. At first > glance a vertical mill looks similar to a drill press, but there are some > important differences, such as a spindle that can take side-loads as well as end > loads and an accurate method of moving the work in relation to the spindle on > all three axes. The SHERLINE MILLING MACHINES can perform all of the tasks and > operations that a large commercial machine can perform. Operations such as > milling, fly cutting, precision drilling, and boring are all routine tasks for > the SHERLINE. Because the tool turns rather than the work, much larger parts may > be worked on in a mill (these parts need not be round). The work is securely > held, thus extremely accurate hole patterns can be drilled or bored using the > SHERLINE vertical mill. The longer "X-axis" throw also increases the machine's > versatility over that of the Lathe with the vertical milling column attachment. > It is an extremely rigid, accurate tool which accomplishes tough machining jobs > with ease. > > Model 5000 (5100) > The Model 5000 (5100 metric) features a solid 10" (254mm) aluminum base, > precision machined dovetailed slides with adjustable gibs, permanently > lubricated spindle bearings, adjustable pre-load anti-backlash feed screws on > "X" and "Y" axes, two 1-5/8" (41mm) laser engraved aluminum handwheels, one > 2-1/2" (63mm) laser engraved handwheel with thrust bearings, and many other > features found only on the best commercial machines. This machine along with a > SHERLINE LATHE will enable you to complete almost any job in your own machine > shop. > > *************** end of Sherline text > > These can be controlled both manually and by stepper motor. > For a one-off you would use manual control. If you have a lot of identical > pieces to be done, then you make up a jig to hold the case/panel in place and > produce a control file that tells the CNC machine how to make the shapes you > want cut. You get identical results each time. > > Fr. Tom McGahee > > {Original Message removed}

can these Shermin machines be hooked up so a computer and move the base of the milling machine?? which model?? ----- Original Message ----- From: "Brian Kraut" <KILLspamengaltKILLspamEARTHLINK.NET> To: <RemoveMEPICLISTTakeThisOuTMITVMA.MIT.EDU> Sent: Thursday, May 04, 2000 9:09 PM Subject: Re: Openings in Project boxes [OT] {Quote hidden}> I have one and I use it more than my 30" table Rockwell Mill. > > Thomas McGahee wrote: > > > If you are REALLY interested in a great way to drill your own > > PCBs and fabricate holes and slots and any shape desired in > > panels and cases, you should take a few minutes and check out: > > http://www.sherline.com > > In particular, take a look at the Sherline vertical mill: > > #5000-CNC (inch version): > > Standard vertical mill w/ 10" base plus 3 stepper motor mounts > > (Metric P/N 5100-CNC) > > $750.00 > > > > This has the stepper motor mountings so you can put three > > stepper motors on and have yourself a PIC numerically controlled > > drill press/milling machine. A quick excerpt from the data available > > at the website: > > > > ****************** Beginning of Sherline text. > > > > The main difference between a lathe and a mill is that on a lathe, the work > > turns and the cutting tool is stationary, while on a mill, the tool turns and > > the work is stationary. Because of the tremendous number of operations that can > > be performed on a vertical mill, it is commonly regarded as the most important > > machine in the modern machine shop... the work horse of the industry. At first > > glance a vertical mill looks similar to a drill press, but there are some > > important differences, such as a spindle that can take side-loads as well as end > > loads and an accurate method of moving the work in relation to the spindle on > > all three axes. The SHERLINE MILLING MACHINES can perform all of the tasks and > > operations that a large commercial machine can perform. Operations such as > > milling, fly cutting, precision drilling, and boring are all routine tasks for > > the SHERLINE. Because the tool turns rather than the work, much larger parts may > > be worked on in a mill (these parts need not be round). The work is securely > > held, thus extremely accurate hole patterns can be drilled or bored using the > > SHERLINE vertical mill. The longer "X-axis" throw also increases the machine's > > versatility over that of the Lathe with the vertical milling column attachment. > > It is an extremely rigid, accurate tool which accomplishes tough machining jobs > > with ease. > > > > Model 5000 (5100) > > The Model 5000 (5100 metric) features a solid 10" (254mm) aluminum base, > > precision machined dovetailed slides with adjustable gibs, permanently > > lubricated spindle bearings, adjustable pre-load anti-backlash feed screws on > > "X" and "Y" axes, two 1-5/8" (41mm) laser engraved aluminum handwheels, one > > 2-1/2" (63mm) laser engraved handwheel with thrust bearings, and many other > > features found only on the best commercial machines. This machine along with a > > SHERLINE LATHE will enable you to complete almost any job in your own machine > > shop. > > > > *************** end of Sherline text > > > > These can be controlled both manually and by stepper motor. > > For a one-off you would use manual control. If you have a lot of identical > > pieces to be done, then you make up a jig to hold the case/panel in place and > > produce a control file that tells the CNC machine how to make the shapes you > > want cut. You get identical results each time. > > > > Fr. Tom McGahee > > > > {Original Message removed}

Yes! The models referred to below (5000/5100) both have the necessary mounts to allow you to attach stepper motors to all three axis. It is not at all difficult to control these things. There are even commercial software packages available that will give you all the control you need. I have done work on a unit that uses a Motorola 68HC11 to provide intelligent control of all three axis using a single high speed serial connection to a PC running Windows95/98. It is even EASIER to do the control using a PC running good old DOS!!! BUT!!! For the kind of simple control that you would need to route holes and rectangular cutouts and the like, you can easily do all the math stuff on the PC side. As to controlling the steppers, that is a piece of cake. I have done all of the following: 1) Use one parallel port. This has 12 latched outputs and 5 real-time inputs. 4 bits can directly control a stepper motor. You need to have the parallel port outputs drive transistors or FETs so you have sufficient drive current for the stepper motors. Use some of the inputs to provide limits switch information and homing information. You need homing information for each axis. You can leave out limit switch info if you want. If you DO implement limit switches they can all share a single input. 2) Use a single serial port. This requires a PIC or some other controller connected to the PC. The PIC must receive the serial data and then control each of the three axis stepper motors appropriately. It is useful to either use xon/xoff protocol or hardware handshaking to control the flow of data. The PIC UART transmitter should be used to inform the PC that the requested action has been performed. (Like an ACKnowledge). If limit switch info indicates that a limit has been reached, the PIC makes sure that appropriate action is taken, including informing the PC. 3) Use a commercially available multi-i/o board. You can get a cheap one for about $100. You can get them with many different configurations, but something like the 32 bit model, which is 4 8 bit ports is best. 4) Roll your own. Not all that hard. A few 8 bit latches, some glue logic, a simple address/port decoder and you are in business. ************* I cannot go into great detail about the hardware/software right now, but suffice it to say that a PIC 16C74 is more than sufficient to provide the necessary i/o and "intelligence". Fr. Tom McGahee {Original Message removed}

which stepper motor would you use for the sherline mill or lathe?? Do stepper motors come set up to step in different increments or is this what you are doing when you build your pic controller?? Thanks in advance... If you have a specific stepper motor that you have used on these particular machines, let me know. ----- Original Message ----- From: "Brian Kraut" <spamBeGoneengaltspamBeGoneEARTHLINK.NET> To: <TakeThisOuTPICLISTEraseMEspam_OUTMITVMA.MIT.EDU> Sent: Thursday, May 04, 2000 9:09 PM Subject: Re: Openings in Project boxes [OT] {Quote hidden}> I have one and I use it more than my 30" table Rockwell Mill. > > Thomas McGahee wrote: > > > If you are REALLY interested in a great way to drill your own > > PCBs and fabricate holes and slots and any shape desired in > > panels and cases, you should take a few minutes and check out: > > http://www.sherline.com > > In particular, take a look at the Sherline vertical mill: > > #5000-CNC (inch version): > > Standard vertical mill w/ 10" base plus 3 stepper motor mounts > > (Metric P/N 5100-CNC) > > $750.00 > > > > This has the stepper motor mountings so you can put three > > stepper motors on and have yourself a PIC numerically controlled > > drill press/milling machine. A quick excerpt from the data available > > at the website: > > > > ****************** Beginning of Sherline text. > > > > The main difference between a lathe and a mill is that on a lathe, the work > > turns and the cutting tool is stationary, while on a mill, the tool turns and > > the work is stationary. Because of the tremendous number of operations that can > > be performed on a vertical mill, it is commonly regarded as the most important > > machine in the modern machine shop... the work horse of the industry. At first > > glance a vertical mill looks similar to a drill press, but there are some > > important differences, such as a spindle that can take side-loads as well as end > > loads and an accurate method of moving the work in relation to the spindle on > > all three axes. The SHERLINE MILLING MACHINES can perform all of the tasks and > > operations that a large commercial machine can perform. Operations such as > > milling, fly cutting, precision drilling, and boring are all routine tasks for > > the SHERLINE. Because the tool turns rather than the work, much larger parts may > > be worked on in a mill (these parts need not be round). The work is securely > > held, thus extremely accurate hole patterns can be drilled or bored using the > > SHERLINE vertical mill. The longer "X-axis" throw also increases the machine's > > versatility over that of the Lathe with the vertical milling column attachment. > > It is an extremely rigid, accurate tool which accomplishes tough machining jobs > > with ease. > > > > Model 5000 (5100) > > The Model 5000 (5100 metric) features a solid 10" (254mm) aluminum base, > > precision machined dovetailed slides with adjustable gibs, permanently > > lubricated spindle bearings, adjustable pre-load anti-backlash feed screws on > > "X" and "Y" axes, two 1-5/8" (41mm) laser engraved aluminum handwheels, one > > 2-1/2" (63mm) laser engraved handwheel with thrust bearings, and many other > > features found only on the best commercial machines. This machine along with a > > SHERLINE LATHE will enable you to complete almost any job in your own machine > > shop. > > > > *************** end of Sherline text > > > > These can be controlled both manually and by stepper motor. > > For a one-off you would use manual control. If you have a lot of identical > > pieces to be done, then you make up a jig to hold the case/panel in place and > > produce a control file that tells the CNC machine how to make the shapes you > > want cut. You get identical results each time. > > > > Fr. Tom McGahee > > > > {Original Message removed}

The stepper motor mount provided by Sherline will accomodate ANY type 23 stepper motor. Type 23 refers to the mounting arrangement only (mounting hole pattern and size, diameter of shaft). You are free to use whatever type of stepping motor as long as it uses a type 23 mounting arrangement. You are free to use single stepping, half stepping, microstepping, or any other drive style you want. The torque does not have to be all that high, since the screw drive of the xyz axis effectively "gears down" the velocity and increases the mechanical force. If you will be working metal, it is best to get a robust stepper. For working plastic you can get away with very lightweight steppers. It is best to get steppers that have the shaft coming out both ends, so that you can also affix the manual rotary handles supplied with the machine. Fr. Tom McGahee {Original Message removed}