Is that Yaskawa?We put a VFD on this PEXTO roller which you can see on the lower left of the machine. Works awesome.
Dang you know your vfd's! Yes it is a Yaskawa. Have you had good or bad experiences with this brand?Is that Yaskawa?
I've been researching and the Hobby Machinist Forum has lots of information. Mark Jacobs (mksj) there has developed some very nice setups for Precision Matthews lathes. The PM lathes are somewhat similar to mine, except they are gear drive spindles, and mine is a belt drive.
My lathe is essentially identical to a Jet BDB-1340 (not the BDB-1340A, which has a different style of quick change gearbox) the the extent that many of the part numbers in the manual match the Jet numbers of the BDB-1340A! It has a D1-4 chuck mount and a 1-1/2" spindle bore. It was made in 2004, but hardly used before the motor burned up. It is one of many Asian lathes of that period that seem identical except for the name on the headstock!
I ended up buying a Hitachi WJ-200-015LF because of Mark's extensive wiring diagrams. They make it straightforward to do the installation, wiring, and programming. I'm going to use a 2 HP, 1725 RPM, 3 phase motor with a 145T frame size. This should give me a great range of spindle speeds, and I can change the belts if I need to slow it way down, and engage the back gears if I need to. I'm putting a magnetic tachometer on the spindle so I won't have to do calculations.
Here are a couple of photos of the machine after some clean up. It was covered with dirt, oil, and swarf. It looked really ratty when I inspected it, but it turns out that most of the dirt layer was actually the cosmoline from the factory! The face plate and 4-jaw chuck still had paper wrapping, and the mounting pins had never been installed in the 4-jaw. It came with the stand, steady and follower rests, turret tool post, two dead centers, headstock Morse Taper reducer, tool kit, and a keyless drill chuck for the tailstock.
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Dang you know your vfd's! Yes it is a Yaskawa. Have you had good or bad experiences with this brand?
Yaskawa is top tier.
It is a 5hp motor attached to a tubing roller. Ive always been told to double the vfd's size for single phase input hence why I was looking for a 10hp vfd. It seems like every vfd I see is rated for 3 phase input to 3 phase output at least those in the 10 hp range, or even 7.5 hp range for that matter. Having alot of trouble finding one rated for 1 phase input to 3 phase output that is 10hp.You can use a 20hp Hitachi SJ-P1 to power a typical 10hp from single phase. I’m doing it and it works well. It’s rated to do it.
What is the 10hp motor connected to?
Thanks for the info and the website address!Look at your motors full load amps (FLA). The attached document shows you each drives rated output with single phase supply. It's the motor current that matters, not HP. I am using this drive, supplied by single phase 240, on two CNC machines with great success. They are great drives. I buy them from https://www.driveswarehouse.com
I just bought a 30hp SJ-P1 to replace a dying A500. it actually came with a printed addendum for single phase use.Look at your motors full load amps (FLA). The attached document shows you each drives rated output with single phase supply. It's the motor current that matters, not HP. I am using this drive, supplied by single phase 240, on two CNC machines with great success. They are great drives. I buy them from https://www.driveswarehouse.com
I just bought a 30hp SJ-P1 to replace a dying A500. it actually came with a printed addendum for single phase use.
I am somewhat confused, which is easily done mind you. I thought a VFD was built to either have single phase input or three phase input. One or the other but not both. I know some are converters for the output but the input is either single phase, or it is 3 phase, they are not able to have both a 3 phase or a 1 phase input depending on what the installer has wired in their shop correct? Reading some comments it almost seems as though a vfd can run on single or three phase input on the same unit but I thought it was just one or the other.I just bought a 30hp SJ-P1 to replace a dying A500. it actually came with a printed addendum for single phase use.
the more you know about how VFDs are built, the more sense it makes.I am somewhat confused, which is easily done mind you. I thought a VFD was built to either have single phase input or three phase input. One or the other but not both. I know some are converters for the output but the input is either single phase, or it is 3 phase, they are not able to have both a 3 phase or a 1 phase input depending on what the installer has wired in their shop correct? Reading some comments it almost seems as though a vfd can run on single or three phase input on the same unit but I thought it was just one or the other.


That look a bit tighter than the recommended 10cm/4" top clearance but otherwise I like what I see.
I'm not sweating that piece at all.That look a bit tighter than the recommended 10cm/4" top clearance but otherwise I like what I see.


Great info thank you very much for clarifying.Most modern 3 phase input VFD's, can be run off of single phase in a derated mode, many smaller factory VFD lathes and mills allow single phase or 3 phase input. In essence a single phase VFD is just an oversized 3 phase model, and the most common single phase VFD's are 3 Hp and under, a few have 5 Hp models. Beyond that it is not practical for VFD makers to offer models specifically for single phase use, but many provide a derating for single phase input. The typical derating for single phase was a factor of ~1.7, but it can vary widely based on the application and VFD model. It is not enough to match up the Hp rating, you need to look at the VFD output in amps for the particular load. Newer VFD's that I have seen come to market have much more significant deratings for single phase use. Example below is for the DURApulse GS20 & GS20X Drive 230V Class – 3-Phase Model-Specific Specifications the factor is 2. Older VFD did detect phase loss for inputs, on some it could be disabled, others it could not. Newer VFD's measure input THD, which is increased with single phase input, Yaskawa drives indicate that the phase loss is not to be deactivated for single phase use, it can cause damage and void the warranty.
Both my mill and lathe which have 3 Hp motors use 3 phase input VFD's and are setup to run off of either single phase or 3 phase power. I have done a number of VFD installs with smaller machines up to 10 Hp using 3 phase input VFDs running off of single phase in a derated mode. Never had any issues. A 3 phase input VFD can also be run off of a RPC, the degree of derating is reduced but is not a factor of 1, so I usually up-size the VFD to the next larger model. It is also recommend to use a DC buss choke on derated VFD's running single phase which help reduce the THD/ripple. Example below is my mill with a factory installed VFD, I extensively modified the control system and added a DC buss choke.
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That is a very clean looking install.Here’s my setup for my Rockwell 20” drill press. It’s a 3HP Huanyang VFD, with controls broken out for forward, reverse, and a jog button for power tapping. I also have the second selector switch set up to switch between two pre-programmed high and low speeds, or allow speed control via the potentiometer on the VFD. Run and stop is controlled by the push buttons on the drill press, and the switch is a DPST 30A disconnect. The goal here was to make it so I never really have to mess with the VFD during the course of normal operation.
Still needs labeling and a metal cover plate, but it’s all working.
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Very nice terminal feature use! That's the true beauty of VFD usage.with controls broken out for forward, reverse, and a jog button for power tapping. I also have the second selector switch set up to switch between two pre-programmed high and low speeds, or allow speed control via the potentiometer on the VFD. Run and stop is controlled by the push buttons on the drill press,
Lol! Got to love the brutal honesty!"Oh ****" button mounted where the original on/off switch was mounted.

I would be concerned of getting metal chips, or other shop debris getting into that VFD. In any type of shop environment I would not mount a VFD in the open, unless it had a sealed enclosure.Here's my very modest contri: A KBDF-27D from KB Electronics, powering a 1.5 HP motor on my 1982 vintage Taiwanese lathe.
Cheers
Mark B
Great looking machine! Is that the Revolution design from Housemade? Was it fun to build, and would you do anything different if you had to do it over? I'm asking because I have a BG build on the back burner. I have a functional BG already but I want something more rigid and powerful.Not really a conversion but just finished building my belt grinder with vfd
Great looking machine! Is that the Revolution design from Housemade? Was it fun to build, and would you do anything different if you had to do it over? I'm asking because I have a BG build on the back burner. I have a functional BG already but I want something more rigid and powerful.
Did you put a fan inside your enclosure, and if so is it filtered? I've heard reports of some enclosures next to a beltgrinder acting like vacuum cleaners, sucking in the dust and depositing it inside the enclosure, unless they had a filter over the fan. If filtered, I assume you have to clean the filter now and then or it'll get clogged, correct? No experience of that myself, it's just hearsay. Wondering what your experience is, or is it too early to say?
Anyway, nice sano* build.
*sano= '60s hot rod slang, short for sanitary, meaning clean and bitchin'.
Thanks for sharing
Mark B


that's how the industrial revolution started. Build machines that enabled you to build better machines - then we went to the moon!Funny thing is I could really have used the BG to build the BG :/.
Funny thing is I could really have used the BG to build the BG :/.
Not sure if I seen the first that you mentioned I watch alot of you tube lol.Have you watched Jeremy Schmidt build his? I think it was on the video where he was making an optional add-on for it when he started shaping something with an angle grinder and then said "oh wait, I almost forgot, I have a belt grinder now"
Also notable (but not for you making your BG, that ship has sailed), check out Fireball Tool's YT channel for a pretty cool way to remove the inside weld from square tubing. He made a slug with a HSS cutting bit like a lathe tool, then dragged that through the tube with a piece of all-thread. The cutting step went fast, but he probably spent more time making the cutter than you did to just hand-file it. And the tool, once made, might not even work on your next square tube because they don't put the weld in the same place relative to the square corners. Still, I thought it was clever. Might be useful someday if you ever need to do it on a tube that's too long to hand-file, can't reach the center.
www.phoenixphaseconverters.com