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Nova DVR drill press

P

PeterT

Ultra Member
Premium Member
Maybe some Darwinian evolution in power tools? Kind of looks like an integrated VFD. And once they have that, can add all kinds of crazy program features. Maybe its the future?
https://www.youtube.com/results?search_query=Nova+DVR+Drill+Press

I've always wondered why Asian hobby mills don't come with VFD straight from the factory. A lot of the motors & electronics come from that part of the world anyways & I would think it would cut out a healthy chunk of the mechanical drive line. Maybe the torque/rpm is still too far to span?

I think I'm going to VFD my bench drill press one day just for the operational flexibility & to learn about the blinky boxes. The iron itself is good. But the motor wont die. Only the Guccibag washing machine & dishwasher motors die!
 
You better make sure it has a LONG warranty that is supported / honored by manufacturer. Or be good in fixing broken electronics. Warranty is ONLY 2 years (!) implication Chinese cheap VFD inside.... "manufactured and assembled in China" Even Everlast welder has 5 years.

Also looks like very light duty - not much meat on her - and yes power rating even at 1.75hp is BS - also not needed in such feather-light machine. Motor power is 1250W - hence they said 1.75hp ... b/c they have motors that are 100% efficient (sure). Of note is the fact it is not a DC motor - it looks like regular 120/240 motor with a VFD and a little computer. Head looks like fiber reinforced plastic - better not hit it with anything.

1583257437482.png


Does not look too "heavy duty" especially with just MT2 spindle. On the other hand it may go up to 5500 rpm. Swing looks like no more then a 12" Maybe 13". Machine weight is not included in the manual.

Note cheap $10 Chinese chuck on it... Same as BB model. What a rip off.

Price is out of this world. Add 200 shipping and tax we are talking well over $2000 for it (!!!)
 
Ya just to be clear, I’m not advocating buying it. It’s crazy expensive & some features seem silly. More that the price of electronics coming down & maybe we will see more machines with VFD type electronic speed control vs pulleys & gears to vary speed from fir the most part single phase residential power so relatively limited rpm range motors. I don’t think it’s a cure all though.
 
I have one like this and I love it, you can adjust RPM just with simply turn a button . What I like when you have a specific RPM you could have it. I don't know if that machine will last long but ,That was a long time I was waiting for that option.
 
Oh no one denies that having a speed controller is cool - I have var speed control on mill and lathe and it is very nice feature. The problem is that you can get a var in a lathe for far less and also in a better made machine - it is 1700 USD - 2300 CAD. plus shipping and tax and you are at ... over 2600 CAD (!)

Actually just by accident found it on sale at KMS for 2000 CAD plus tax - so 2100. It is another Nova but under King brand? Then there is 1300 Rikon with VAR *and* same MT2 6" spindle.... hmmm I feel that same Chinese factory is starting to make a lot of these. PA has small var for 450 but I think I once saw there larger one.

Both of my drill presses are gear based so changing speeds is also very fast - I just paid so much less for mine.
 
PeterT said:
Maybe some Darwinian evolution in power tools? Kind of looks like an integrated VFD. And once they have that, can add all kinds of crazy program features. Maybe its the future?
https://www.youtube.com/results?search_query=Nova+DVR+Drill+Press

I've always wondered why Asian hobby mills don't come with VFD straight from the factory. A lot of the motors & electronics come from that part of the world anyways & I would think it would cut out a healthy chunk of the mechanical drive line. Maybe the torque/rpm is still too far to span?

I think I'm going to VFD my bench drill press one day just for the operational flexibility & to learn about the blinky boxes. The iron itself is good. But the motor wont die. Only the Guccibag washing machine & dishwasher motors die!
Click to expand...
Could you tell me what is VFD ?
 
VFD => Variable Frequency Drive (entraînement à fréquence variable). It allows you to change the RPM of a 3-phase electric motor electronically by adjusting the frequency.
 
The normal rotational speed of a 3ph motor not under load is defined by the frequency of input current and number of poles the motor has minus some slip. At 60Hz in North America a 2 pole motor has a speed just under 3600 rpm, 4 pole motor just under 1800 rpm. A VFD plays around with that 60 HZ and makes it say 30 HZ - decreasing speed to just 1800 / 900. You can go even lower but remember that cooling fan on your motor is also going to spin slowly. Also torque of a motor decreases with speed. So yes you can go 2 Hz but the actual power is going to be ... low.

For a 4 pole motor you can also go up - say to 120 hz and get 3600 rpm or so. This is not recommended for a 2 pole motor (i.e. over-speed to 7200 rpm).

The main issue with a VFD is the problem of the low speed ==> low torque. When you are going slow, you usually want a lot of torque but with a VFD setup this is where you get the least. This is resolved to some degree with simply having huge motors in your machine - you still have plenty of power if you over-sized the motor by factor of say 5.

VFD is also used as a soft start for large motors - large motors draw a lot of current at start, but with a VFD that start can be a gentle one with low draw.

VFDs also have build in, or you can add extra, capacitor based break - i.e. they can slow down the motor considerably and quickly - a useful electronic breaking system.

VFDs are not designed to run multiple motors - problem is that a VFD has limited capacity and a start or stop of additional motor may shock it too much - think of a VFD as a little power plant with a max rated capacity or like a generator. Usually something as small as coolant motor or small resistive load such as a lamp are not an issue - but if you have two similarly sized motors that need to start / stop you are in trouble.

VFDs can also generate 3ph from 1ph power if rated for such operation.

VFDs usually don't have build in transformer circuit and thus cannot provide voltage step up.

VFDs have some distortions in the power they provide.

As to the drill press in question the manufacturer and online stuff makes it a bit of a mystery as to what exact setup is - most of the video stuff is from 2016 / 2017 and it seems to be 100% paid promotion. It is not 100% certain whatever the setup is 380v 3ph motor with a VFD or a DC motor like in mini mill - even the size of the machine is a mystery - on picture above the machine is small - on video it towers over presenter - manufacturer makes it a mystery as to its size.

You can add VFD to your current drill press - usually it is easier to get a VFD for 3ph motor - and upgrade to cheap say 3ph 2hp motor 4pole. With this setup and recommended 1/2 speed to 2x speed VFD settings if you setup the drill press belts to say speed of 300 rpm the range at your fingertips will be 150 rpm - 600 rpm. If you were to go with large 5hp motor setting it at say 500 rpm with belts your useful range would be 125 - 1000. Chinese VFDs are cheap but they do break down - I had one die after less then a year. Hence why warranty on the drill press is just 2 years. Better quality from China is possible - see Everlast welders with 5 year warranty.
 
I saw before an other brand and it was nice. The variable speed was made with a system like a skidoo clutch . I forget the company made ? I buy mine in Ottawa OFS Ottawa Fastener Supply ,before I get my Nova the other brand was there ,I wait to long before I make my move and it was gone, a man say wait the new model will be better ? and it was the Nova.
 
Tom Kitta said:
VFDs also have build in, or you can add extra, capacitor based break - i.e. they can slow down the motor considerably and quickly - a useful electronic breaking system.
Click to expand...

Good summary.
Did you mean resistor for braking or is it really capacitor?
 
Ooops yes it an extra resistor(s) you can add for dynamic breaking.

DC motors BTW have their highest torque when stalled - they generate a lot of torque when going slow BUT they have less HP rating when going slow as well - DC motor torque - speed curve is a line. The rated power is in the middle - i.e. you get maximum power output of DC motor at the middle of speed its rated for.

Above I think confuses pp a bit - the high torque mini mill does not need a back gear but when going at its slowest speed and max load it does not draw its rated 500w.

Or to flip it the other way - a 2hp DC motor going slowly has similar torque to a 1hp AC motor that was geared down.
 
So our Variable speed lathe on board the ship is a 13" Clausing Colchester - 10 Hp but.....Probably only puts about 2 to 3 HP or less into some of the operations at say 30 to 50 RPM. I have stalled it out before at the lower running when a cutter went funny. My 1 Hp gear head SM lathe at home seems to cut equally proficient in most operations. I do lack the top end 3500 RPM though.......
 
Yes you are correct:

1583438841564.png


So if you use VFD and decrease speed by 1/2 to 30 hz you get 5 hp instead of 10 hp in your machine. If you go further - decrease to say 15 Hz you now have 2.5 hp output out of your motor.

So if you want to use a VFD you can oversize the motor based on your needs at lowest speed.

On your VFD there is a display that shows the Hz - if it is very low when you are turning at low RPM then you now know why you can stall the lathe with a heavy cut - it is no longer a 10hp gear head but maybe just a 2hp gear-head.

Note that the same stuff happens when you over-speed the motor - you loose torque ... well nothing is free - if it span 2x as fast and torque was the same then power needed would double - cheap way to buy small motor and make it twice as powerful with ease ;)
 
Ma Nova viens de me lâcher il y a un message dans l'écran Low Voltage la personne qui m'a téléphoné m'a dit que c'était probablement une des deux board une est $200.00 l'autre est $800.00 très décus 3 ans seulement et les problèmes commence. OFS a Ottawa vont la vérifier pour $ 30.00 mais au moins une semaine d'attente. Avez vous des suggestions pour une press drill a vitesse variable ? j'ai déjà vue la Power matic il y a aussi la Wen 4225 se sont des systèmes a clutch semblable aux motoneige en changent la position du bras la vitesse augmente ou diminue. Tout conseil est bienvenue. Si mon message est difficile a comprendre ,je peut essayer de l'écrire an anglais. merci
 
Marc Moreau said:
J'ai vu avant une autre marque et c'était sympa. La vitesse variable a été faite avec un système comme un embrayage de motoneige. J'oublie la société faite ? J'achète le mien à Ottawa OFS Ottawa Fastener Supply, avant d'avoir mon Nova, l'autre marque était là, j'attends trop longtemps avant de déménager et c'était parti, un homme dit d'attendre le nouveau modèle sera mieux? et c'était le Nova.
Click to expand...
C'était une Powermatic mais je ne sais pas si elle était bonne pour le métal ?
 
Marc sorry to hear of your troubles if you would like I would offer to have a look at it for you, with a meter I may be able to do some troubleshooting if the boards are accessible we could do a check over for bad solder connections and check power supply voltages we might get lucky and find something fairly easy to fix it or narrow it down a bit. I am in Ottawa.
 
Ok I have friend here who doing electronic he is suppose to come tomorrow . If he don't find nothing I will probably send you a message. Thank You
 
Is it possible to find a motor with variable RPM to replace my Rexon press drill tire to work with the belt and pulley. The Nova will probably go to the junk yard . Will never buy this again .
 
Well for AC motor modern RPM control is with a VFD - old school would be something like a two speed motor (which was common BTW in drill presses). There are 3 speed motors as well but I only seen them as a fan in a furnace - so 1/2 hp maybe 1 hp max - google says 1 hp is possible.
 
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