hi About powerful welding machine that have higher welding current. i think that if main goal is to deposit as much as possible metal than it is good. like in structural steel manufacturer but in my case people- customers will bring caliber-micrometer- indicator - all imaginary measuring instruments to see how close deposited part to original print-model. i think in this case use of smaller wire will be better - 0.022 something like that. yes it will take longer time to deposit but accuracy of part is most important part. maybe in the future possible to use two welders - like one for rough and one for finish work-- heavy welder will fast deposit as much as possible and small welder will do only external boundary to make part more accurate -- close to the print dimensions etc. some ideas
aram On Thu, Jul 31, 2014 at 8:27 AM, Dave Cole <[email protected]> wrote: > My phase converter is wired very close to this diagram. > > http://www.metalwebnews.com/howto/ph-conv/fig1.html > > I've made two of them using surplus 10hp 3 phase motors. For a while I > could buy surplus 10hp motors that were new for > about $200. That was about 14 years ago. > > I made one for my Dad that is wired like the one in the picture. As long > as you hold down the start button, the additional starting caps are > in the circuit. When you release the button the starting caps fall > out. Those are needed just to get it spinning. > > Mine is a little more basic.. I throw the disconnect on and hold down a > button which switches in the starting caps. Same idea, different manner > to start the converter motor. > > The caps are adjusted to optimize phase currents in load motors. I've > used this converter to supply power to a 3 phase transformer to increase > the voltage to 480 volts - 3 phase to test drives. After the power is > passed through a transformer, the currents and voltages are very well > balanced. I used to use real starting caps but if you holld the > button down too long the caps blow with a bang. So I now use regular > power caps for everything. A timer could be used to switch out the > starting caps also.. But it doesn't take much skill to start up the > converter via a button. > > The biggest motor I have run off this converter is a 10hp motor on an > air compressor. That was no problem but I turned down the max pressure > from 175 psi to 150psi to minimize motor heating due to the unbalance in > the motor currents. I often run a 5 hp lathe off the converter. > > > Dave > > > On 7/31/2014 3:55 AM, andy pugh wrote: > > On 30 July 2014 23:04, Dave Cole <[email protected]> wrote: > >> Phase converters are pretty easy to make if you have a spare 3 phase > >> motor. > > I made a partially succesful one once that also stepped-up the > > voltage. Neutral between star-point and a phase, and then the three > > phases from the phase ends. It needed a 1/4 hp single-phase (or a > > rope) to spin it up, but once it was spinning it continued to spin. > > > > It wasn't a particularly well balanced 3-phase. > > > > > ------------------------------------------------------------------------------ > Infragistics Professional > Build stunning WinForms apps today! > Reboot your WinForms applications with our WinForms controls. > Build a bridge from your legacy apps to the future. > > http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Infragistics Professional Build stunning WinForms apps today! Reboot your WinForms applications with our WinForms controls. Build a bridge from your legacy apps to the future. http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
