Just ordered a Bosch Rexroth EFC5610 1.5kW 230V 1 phase Inverter Drive

[G59]

Also ER11 nuts are available. Just google Balanced ER11 collet nuts and you get thousands of hits.

[jfong]

Yes, no point modifying anything in case you need to return it right away, before even putting any time on it.
That makes sense, but you know as well as I do, others might think this is OK to do all the time and run your machine like that.
OK for you as you have a good understanding of it.

I hope everything works out for you.

This might answer a question.

The first time I ever used/saw a ER nut, I said some colorful words. I really though the nut was machined wrong. A quick Google search taught me what that lip was for.

[A_Camera]

OK, thanks for explaining. I didn't think about that eccentricity, but it makes sense that it should be balanced out for perfect run.

[mactec54]

Yes, and balancing with the spindle means that if you damage that nut or want to have many so you can have your tool changes prepared then you can't buy any spares so you have to throw away that spindle and buy a new one. I think most people wait with that until the motor is dead. But sure, properly balanced nut and spindle is the best solution in an optimal world.

No the Nuts are Balanced individually by themselves, You can use any ER nut that is to the G2.5 spec's/rating, and they are not hard to find most suppliers have them, there are ( 2 ) types, that use different wrenches

[A_Camera]

Also ER11 nuts are available. Just google Balanced ER11 collet nuts and you get thousands of hits.

Well, I tried on eBay but didn't find any. I know eBay search function works differently in different countries, I have had a serious discussion about this with eBay some time ago, and they admitted this, which is pretty annoying to me because I travel a lot, and even if I use exactly the same computer and the same search criteria, I get different results. Anyway, right now and in my home grounds, I can't find any. I found some on Aliexpress for some horrible prices and also some in USA for even more (we are talking about over $40 each, so that's a no-no for a cheap motor. The cheapest I found is in Germany for 27€ piece plus 21€ for shipping, so that's also pretty expensive. I think I'll test the ones I have and compare those with the balanced one I received. If I can't measure, feel or hear any difference then I won't bother, and will continue using mine as they are. If I notice any serious issue I'll look more and in the meantime will use the balanced only. Anyway, thanks for explaining why and what to balance out.

It is pretty logical, this is done with car wheels/tires as well. I guess the larger the radius the more important it is, so I guess this is more important for the larger nuts than the ER11, but I can definitely see the point now.

[A_Camera]

No the Nuts are Balanced individually by themselves, You can use any ER nut that is to the G2.5 spec's/rating, and they are not hard to find most suppliers have them, there are ( 2 ) types, that use different wrenches

OK, thanks. Found a German site, they say it is balanced G6.3 which is up to 15k RPM. If I experience any issues I'll look deeper into it.

Clamping nuts ER11 | 1-7 | SW17 | balanced - Kemmler Pr

It is not specified how well balanced the nut I have is, I doubt it is up to the highest standard, but the runout is stated to be less than 0.005mm.

Yes, I know there are two types of ER11 nuts, I prefer the hexagonal type, these are the ones I have.

[mactec54]

OK, thanks. Found a German site, they say it is balanced G6.3 which is up to 15k RPM. If I experience any issues I'll look deeper into it.

I must be missing something here, the only Nuts you can use have to be rated for your spindle max RPM 24,000, a Nut that has been Balance checked for G6.3 15,000 RPM is not suitable for your spindle that will be running with a minimum of 18,000 RPM up to 24,000 RPM, Just remember your spindle can not run slower than 18,000 RPM because of your choice, to get an air cooled spindle

[A_Camera]

I must be missing something here, the only Nuts you can use have to be rated for your spindle max RPM 24,000, a Nut that has been Balance checked for G6.3 15,000 RPM is not suitable for your spindle that will be running with a minimum of 18,000 RPM up to 24,000 RPM, Just remember your spindle can not run slower than 18,000 RPM because of your choice, to get an air cooled spindle

Seems like a new misunderstanding here...

I didn't say I will buy those, just that if necessary, I'll look deeper into this, meaning, I'll look around and see what I can find for a reasonable price.

As for the minimum speed... well, I'll check that out. There is really no "brick wall" at 18k RPM, I have heard others saying that even down to 6k it is safe as long as the motor is not heavily loaded or run for very long. Most of my milling passes are fairly light, so I really don't think that running below 18k will be a big issue. But... as I said, I'll check. Remember that I am monitoring all the temperatures, including the spindle, so I am pretty sure I'll find the optimal limit easily.

[mactec54]

OK, thanks. Found a German site, they say it is balanced G6.3 which is up to 15k RPM. If I experience any issues I'll look deeper into it.
Clamping nuts ER11 | 1-7 | SW17 | balanced - Kemmler Pr
It is not specified how well balanced the nut I have is, I doubt it is up to the highest standard, but the runout is stated to be less than 0.005mm.
Yes, I know there are two types of ER11 nuts, I prefer the hexagonal type, these are the ones I have.

Then why bother to post what is not reverent, to what your needs are

Seems like a new misunderstanding here....

There has never ever been a misunderstanding, it seems everything anyone posts you come out with an incorrect reply, and say it’s just a misunderstanding

As for the minimum speed... well, I'll check that out. There is really no "brick wall" at 18k RPM, I have heard others saying that even down to 6k it is safe as long as the motor is not heavily loaded or run for very long. Most of my milling passes are fairly light, so I really don't think that running below 18k will be a big issue. But... as I said, I'll check. Remember that I am monitoring all the temperatures, including the spindle, so I am pretty sure I'll find the optimal limit easily.

6,000 RPM with light cutting, keep dreaming, even the water cooled have trouble running at 6,000 RPM

I guess yours is special because you brought it, its minimum rated speed is 18,000 RPM

That is why water cooled spindles are better, they can run slower, run a lot quieter, and have a longer life in general

[A_Camera]

6,000 RPM with light cutting, keep dreaming, even the water cooled have trouble running at 6,000 RPM

OK.

I guess yours is special because you brought it, its minimum rated speed is 18,000 RPM

Where is it specified that the minimum RPM is 18k? Anyway, did I say mine is special? No. I said "I have heard others saying that even down to 6k it is safe" and that I will check it out. Is there something wrong in that? After all, it is my motor.

So please, instead of using that sarcastic tone, read my post twice before replying, because I am surely tired of repeating that you misunderstood my post again... I start to suspect that you don't really read it, just fragments of it.

That is why water cooled spindles are better, they can run slower, run a lot quieter, and have a longer life in general

OK fine. I never said water cooled are not better, did I? I bought air cooled, it was my decision and if I don't like it I'll buy a water cooled one later. That's all, no big deal.

Another thing... as I said before, I respect your knowledge but don't appreciate your sarcasm and rudeness, in fact I am pretty tired of that tone. So if you can't write anything without that sarcastic rudeness than please don't write at all.

[mactec54]

Another thing... as I said before, I respect your knowledge but don't appreciate your sarcasm and rudeness, in fact I am pretty tired of that tone. So if you can't write anything without that sarcastic rudeness than please don't write at all.

The only one being rude and sarcastic is you, if you think what I have posted is rude and sarcastic, then you need to wait until I see you post more of your uneducated rubbish

[asuratman]

A_Camera,
When you wiring the VFD to motor, keep us posted. I have the same spindle as yours. I will purchase Hitachi VFD.

[A_Camera]

A_Camera,
When you wiring the VFD to motor, keep us posted. I have the same spindle as yours. I will purchase Hitachi VFD.

Don't worry, I will post the results and also demo whatever there is to show, even though mactec54 calls it "uneducated rubbish" which I suppose he regards as a not rude or sarcastic remark at all...

My cable just got delivered a few minutes ago. 4 x 2.5mm2 wire shielded motor cable designed for drag chain. Feels nice, but I will not start soldering yet because currently I am in discussion with the motor seller about the damaged foam (see pictures above) which shows that the motor was dropped before shipping. Have you modified the motor so that it now has a protective earth connection to the motor casing? If not, than you should really be careful with it. I don't recommend using it without, I will test mine but if the motor spins up and down on my desk then I'll modify mine immediately after, before installing on the CNC.

I was considering a Hitachi VFD as an option, but I decided to go for the Bosch because I felt that it is better documented and it has more features which I found very useful. It is also a vector controlled type (SVC = Sensorless Vector Control) so it won't lose torque on lower RPM and doesn't need super-expensive motor. It has a motor auto tuning feature, which I think is good when one is trying to use a Chinese spindle without much data... anyway, I will not know how well it is working for a few more weeks, since I have to wait for the VFD to be delivered and that won't happen until the end of May. In the meantime, I'll rebuild my power supply and control box...

[A_Camera]

The only one being rude and sarcastic is you, if you think what I have posted is rude and sarcastic, then you need to wait until I see you post more of your uneducated rubbish

[asuratman]

That 4 x 2.5mm2 wire shielded motor cable for spindle 1.5 kw is too big? It does not fit to connector on the spindle.

[A_Camera]

That 4 x 2.5mm2 wire shielded motor cable for spindle 1.5 kw is too big? It does not fit to connector on the spindle.

You made me worried... so I had to check. It fits, but it is a tight fit.




Will not be an easy task to solder, but I have managed more difficult tasks in my life, so I guess I manage this time also. If I have problems I'll order a 4 x 1.5mm2 but the Bosch specs says 2.5mm2 so I'll use that if possible.

Note that the above image is just showing a temporary fitting. I'll fix the final one as it supposed to be, but what is important is that the shield fits the collar without problems.

[mactec54]

You made me worried... so I had to check. It fits, but it is a tight fit.




Will not be an easy task to solder, but I have managed more difficult tasks in my life, so I guess I manage this time also. If I have problems I'll order a 4 x 1.5mm2 but the Bosch specs says 2.5mm2 so I'll use that if possible.

Note that the above image is just showing a temporary fitting. I'll fix the final one as it supposed to be, but what is important is that the shield fits the collar without problems.

We would love to see how the final connection is made, because no matter what you do it will be incorrect

This show's how not to wire/assemble these plugs, this being a bad example, I hope others that need to wire plugs like this see this post, and research on how to do it correctly, and use the correct wire/cable size for the job in hand

As asuratman has already said. your cable is way to big for a 1.5KW spindle, the Bosch wire specs have nothing to do with your spindle needs, there specs are for what the max of the drive can output, not what you are attaching to it, like your spindle with a Max of 7 Amps

The cable you have is good for a 3KW spindle with a safety factor, you have a max of 7 Amps, even a quality cable of 1.5 wire size will give you a 22 amp rating, which is enough for a 2.2KW spindle with safety, and way more than what you need for your spindle, but this size cable will fit the Plug correctly that these Spindles have, what you have does not

It also show how far off the Bosch Specs are as they have the same size cable listed for the input and the output as the same, you don't have to know very much to see that this is incorrect for your needs, the input see's roughly twice the AMPS as what the output does, so go figure

[A_Camera]

If I have problems I'll order a 4 x 1.5mm2
Note that the above image is just showing a temporary fitting.

We would love to see how the final connection is made, because no matter what you do it will be incorrect

This show's how not to wire/assemble these plugs, this being a bad example, I hope others that need to wire plugs like this see this post, and research on how to do it correctly, and use the correct wire/cable size for the job in hand

As asuratman has already said. your cable is way to big for a 1.5KW spindle, the Bosch wire specs have nothing to do with your spindle needs, there specs are for what the max of the drive can output, not what you are attaching to it, like your spindle with a Max of 7 Amps

The cable you have is good for a 3KW spindle with a safety factor, you have a max of 7 Amps, even a quality cable of 1.5 wire size will give you a 22 amp rating, which is enough for a 2.2KW spindle with safety, and way more than what you need for your spindle, but this size cable will fit the Plug correctly that these Spindles have, what you have does not

It also show how far off the Bosch Specs are as they have the same size cable listed for the input and the output as the same, you don't have to know very much to see that this is incorrect for your needs, the input see's roughly twice the AMPS as what the output does, so go figure

https://en.wikipedia.org/wiki/Electr...United_Kingdom




Yes, the Bosch manual as well as the Wiki page is over-dimensioning the cable, I know that very well, but it's called "safety margin" in my territory and the way I see it, there is NOTHING wrong with safety margins, at least not where I come from.

In the meantime... I'll carry on if you don't mind, and also still waiting for your evidence that my air cooled spindle is not possible to run below 18k rpm. After all, you have said that: "its minimum rated speed is 18,000 RPM" WHERE is it rated? Again, I am not saying you are wrong, but it would be nice to see where that rating comes from.

[G59]

If you can fit bigger wires then what's the problem?

Too small and now it gets serious, but you know that already.

I wouldn't worry too much about it as my last build using Yaskawa drives I put in whatever I had available. As long as it's within the minimum specs. When using connectors, now that can get trickier to properly solder. Mactec only sounds like he's being critical, but I think he's looking out for the others that will stumble on to this thread, that don't have a clue as to what they are doing.

[G59]

As for spindle minimum speed, if you google it, the spindle you have is considered useless under 8000 RPM. From what I gather, no torque below that and too much heat generated in the armature. It's not just one person saying it, even those with Shapeko variants are stating it.

Personally I have no experience with any of the Chinese spindles so I'm gonna sit back on the sidelines and not get involved.

Good luck.