Can one machine do paste dispense, pick/place, drill holes, etc? - Page 1
Forum section: electronics / general

author: Merlysys
author_rank: Regular Contributor
timestamp: October 08, 2015, 11:43:52 am
content: I am researching PnP machines and see that it is basically a CNC machine with a specialized head. For hobby and low volume purposes a machine whose head can be changed to:dispense pastepick and placedrill holes...maybe even remove copper from copper clad boardsHas anyone made such a device? If so please detail here.If not...I was looking into building own PnP by following plans freely available but now thought of changing the project to one with a changeable head. Is that realistic, what problem will I encounter? I know the machine will have to be powerful enough and also agile to handle heads with such broad characteristics.Which forum is best for getting help for such a device?

author: Bud
author_rank: Super Contributor
timestamp: October 08, 2015, 01:57:49 pm
content: You forget milling, laser engraving, and chocolate cake 3d printing.I say do not waste your time but since you are not going to listen anyway i wish you luck.

author: Kjelt
author_rank: Super Contributor
timestamp: October 08, 2015, 02:28:48 pm
content: Quote from: Merlysys on October 08, 2015, 11:43:52 amBUZZER wrong answer.A CNC machine has to be build very sturdy because it has to take large forces during the milling (esp. the horizontal forces on the router) and you don't want it to be misplaced 1/100 of an inch during the milling. First parameter of importance for a CNC: sturdyness Second parameter: accuracy Third parameter: speed.A P&P machine has to move very fast but has little to no forces during the vertical axis only placements.First parameter of importance for a CNC: accuracy Second parameter: speed.Paste dispenser with a syringe is incredibly slow , use a stencil and it takes seconds.If you think one machine can do it all, it will take forever to do everything since it has to do milling it has to be sturdy which means it will be slow, way to slow to be usefull for P&P.

author: CrashO
author_rank: Unknown
timestamp: October 08, 2015, 02:45:49 pm
content: Cirqoid comes to mind. Only "affordable" (still way to expensive for my hobbyist taste) machine doing all you ask for, albeit beining pretty slow..Runs at about $3000if you want all the options on it, and you manually have to switch out certain parts if you want to transfer from milling to paste, etc.I have no experience with the machine itself, but came across it a while ago whilst searching for lowcost cnc's

author: eneuro
author_rank: Super Contributor
timestamp: October 09, 2015, 05:55:33 pm
content: Quote from: CrashO on October 08, 2015, 02:45:49 pmMakeing prototype driled PCBs without manufactured vias doen't make to much sense, so I'd rather looking for decent speed PnP with CV-so building myself oneThis shown here It is so slow that doing PnP manually looks like might be much faster since yuo have to watch what this m,achine is doing-you can't let it automatically change tools, etc.For me is useless even for prototyping.Removeing copper layer by CNC methods creates damage to PCB core, and make those PCBs mechanically weak

author: Falcon69
author_rank: Super Contributor
timestamp: October 09, 2015, 11:01:08 pm
content: I don't think it would be possible to have one do all. The problem is, for milling purposes, as someone has already stated, the machine needs to be built very ridgid and the gantries usually are heavy because of this, which would effect speed. Because of that, even if you had extra stepper motors to mechanically automatically switch different steppers or servos to operate different modes of the machine for speed/accuracy/ridgidness, those faster servos/steppers would have trouble moving the mass of the gantry that would be needed for the milling purposes.There's alot of factors to configure. One of which is impossible to get around and that is physics.You could however built a milling machine that could do routing, laser cutting,plasma cutting, and even 3D printing. One set of steppers or servos could handle that as speed is usually not a HUGE factor, but it won't do P&P because of the speed needed to do that, or accuracy.

author: Spikee
author_rank: Frequent Contributor
timestamp: October 09, 2015, 11:08:23 pm
content: My CNC can do 6m/min reliable with pretty much no step loss. Even turning it up to 9 or 12m/min should not be to hard.This is a ~10K machine (new)A pnp only has to be as fast as you want it to be. Higher speed = more maintenance because you are hauling around a reasonably heavy head and bed at high speed.But for prototyping work / hobby work is is more than adequate. You could even make the head detachable and put a light pnp head on it to solve the problem.As long as you have G-CODE generated for what you want to do ... a CNC can all do it.Edit:Cheapo china closed loop steppers(2nm) can do 6m/min milling with a 20Kg head no problem , no step loss. The higher speed spindles used now on machines are not that heavy. I'm not talking about the 30KW big VMC's used in factories with a few hunderd kg head. Talking about <10Kw machines made from steel / epoxy granite (with steel structure). Who weigh generally in the 300-500kg mark. Those big Factory VMC's are 5000kg and upwards made for 24/7 use and cost 500K euro.It is all about software these days ,not hardware.Talking about hobby / small company stuff here. So what if it does 1-3K CPH it is plenty for a few proto's or even small runs. If you need more than just send it to a third pnp party. Will be cheaper than investing another 100K because you want to place a few more components an hour. In that case just buy a decent pnp for the side...