[ericks]

I need more help re the spindle motor please. The supplier is giving me the option to choose the collet size. Should i choose ER20 or ER25??

Many thanks
Erick

[ger21]

Do you have all the specs on the two spindles?

ER25 is a larger collet, which usually means a larger spindle shaft, and larger bearings. I've seen some ER25 spindles limited to 18,000 rpm, where an equivalent ER20 spindle was capable of 24,000 rpm.

[ericks]

Do you have all the specs on the two spindles?

ER25 is a larger collet, which usually means a larger spindle shaft, and larger bearings. I've seen some ER25 spindles limited to 18,000 rpm, where an equivalent ER20 spindle was capable of 24,000 rpm.

The spindle motor is a 18000 RPM unit. their 24000 rpm motor has ceramic bearings. They give an option for 20 or 25. I really don't think i need a 25....it's only a router after all. What do you think Gerry?

[ger21]

Not knowing anything about these spindles, It's hard to make a recommendation.
Collet size alone really makes no difference.

[LeeWay]

I would recommend the ER20 if I were buying it.
I have ER16, ER20 and ER32 that I use on my milling machines.
Both of my routers use ER20. It can hold a 1/2" tool and I think that is plenty big for a router.
Also collets may not be as widely available for the ER25. I haven't actually looked though. I use several collet nuts and many different collets for each router, so the availability of those are important.

[wizard]

The spindle motor is a 18000 RPM unit. their 24000 rpm motor has ceramic bearings. They give an option for 20 or 25. I really don't think i need a 25....it's only a router after all. What do you think Gerry?

Well im not Gerry but i see ER20 as the minimal size for a versatile wood working machine. This simply due to the collets ability to handle 1/2" diameter tooling. You would only go smaller on a machine dedicated to engraving or small parts. On the flip side you may not have much of a need or even the capability to go above 1/2" tooling.

By capability i mean a router frame that is stiff enough to make using larger tools worthwhile and a router motor with the required torque capability at lower speeds. There are other considerations that might indicate a larger ER collet. For example you need a large tool stick out to handle a pocket or odd feature. A larger diameter cutter will be stiffer in such a use case. In some cases the spindle will be stiffer also, it depends upon the specific spindles design. Another consideration is if you do a lot of profiling work a large diameter round nose cutter may be advantageous.

One thing a guy years ago tried to tell me (i have no way to test) is that a larger diameter tool will cut cleaner and last longer. This due to small cutters having aggressive clearances to work with the small diameters. This makes sense, to an extent, when you compare shaper cutters to router cutters and the results often seen on shapers. Hopefully somebody with experience can comment on this.

In general though i see 1/2" cutter capacity as the minimal size cutter on any reasonable robust router.

[ericks]

Not knowing anything about these spindles, It's hard to make a recommendation.
Collet size alone really makes no difference.

I can understand that....they have very little information on their equipment, which is obviously not good. Must say i like the way the motor frames are designed, saw one video where someone was ramping one up and down. Sounded quite smooth...

[ericks]

I would recommend the ER20 if I were buying it.
I have ER16, ER20 and ER32 that I use on my milling machines.
Both of my routers use ER20. It can hold a 1/2" tool and I think that is plenty big for a router.
Also collets may not be as widely available for the ER25. I haven't actually looked though. I use several collet nuts and many different collets for each router, so the availability of those are important.

Thanks....i really don't think i will use bigger than 1/2''.

[ericks]

Well im not Gerry but i see ER20 as the minimal size for a versatile wood working machine. This simply due to the collets ability to handle 1/2" diameter tooling. You would only go smaller on a machine dedicated to engraving or small parts. On the flip side you may not have much of a need or even the capability to go above 1/2" tooling.

By capability i mean a router frame that is stiff enough to make using larger tools worthwhile and a router motor with the required torque capability at lower speeds. There are other considerations that might indicate a larger ER collet. For example you need a large tool stick out to handle a pocket or odd feature. A larger diameter cutter will be stiffer in such a use case. In some cases the spindle will be stiffer also, it depends upon the specific spindles design. Another consideration is if you do a lot of profiling work a large diameter round nose cutter may be advantageous.

One thing a guy years ago tried to tell me (i have no way to test) is that a larger diameter tool will cut cleaner and last longer. This due to small cutters having aggressive clearances to work with the small diameters. This makes sense, to an extent, when you compare shaper cutters to router cutters and the results often seen on shapers. Hopefully somebody with experience can comment on this.

In general though i see 1/2" cutter capacity as the minimal size cutter on any reasonable robust router.

Interesting....i will keep this in mind for sure, Thanks

[Heavymetalcnc]

Generally, the only reason a larger tool will last longer than a smaller tool is not enough RPM. In most cases, max spindle speed is just not enough to truly run a small diameter too fast enough. Where surface footage is much easier to obtain with a larger tool.

[paul3112]

For collet ranges. 13mm will let you use 1/2 wood working bits.
https://www.aliexpress.com/store/pro...694319c5ZC3l11
For PCB drilling the ER 11 adapter night be useful
https://www.aliexpress.com/store/pro...5c9acf6cKR9AIE
Note** only a couple of the smaller sizes of the ER11 collets needed. The 100mm ER11shank might need to be reduces ,Z height issues.
Hope that helps

Paul

[ericks]

For collet ranges. 13mm will let you use 1/2 wood working bits.
https://www.aliexpress.com/store/pro...694319c5ZC3l11
For PCB drilling the ER 11 adapter night be useful
https://www.aliexpress.com/store/pro...5c9acf6cKR9AIE
Note** only a couple of the smaller sizes of the ER11 collets needed. The 100mm ER11shank might need to be reduces ,Z height issues.
Hope that helps

Paul

Thanks Paul

[ericks]

Spindle update....currently i am considering buying the spindle motor from another supplier, Hertz's customer service is not great

[mactec54]

For collet ranges. 13mm will let you use 1/2 wood working bits.
https://www.aliexpress.com/store/pro...694319c5ZC3l11
For PCB drilling the ER 11 adapter night be useful
https://www.aliexpress.com/store/pro...5c9acf6cKR9AIE
Note** only a couple of the smaller sizes of the ER11 collets needed. The 100mm ER11shank might need to be reduces ,Z height issues.
Hope that helps

Paul

That would be ridiculous to use a ER11 Collet chuck in a ER 20 or even a ER 25 spindle, the amount sticking out of the spindle would not be good even if you had the extra room, it does not matter what size he goes with you can get collets down to 1mm with any ER chuck spindle size you use

Any ER collets you buy want to be in the .0002" or .005mm if not you are wasting your money

[ger21]

That would be ridiculous to use a ER11 Collet chuck in a ER 20 or even a ER 25 spindle

+1

I use 1/8" ER32 collets with 1/32" bits.

[skrubol]

That would be ridiculous to use a ER11 Collet chuck in a ER 20 or even a ER 25 spindle, the amount sticking out of the spindle would not be good even if you had the extra room, it does not matter what size he goes with you can get collets down to 1mm with any ER chuck spindle size you use

Any ER collets you buy want to be in the .0002" or .005mm if not you are wasting your money

Unless your Z can't get close enough for small, short tooling.

A better solution might be additional spoil board though.

[paul3112]

That would be ridiculous to use a ER11 Collet chuck in a ER 20 or even a ER 25 spindle, the amount sticking out of the spindle would not be good even if you had the extra room, it does not matter what size he goes with you can get collets down to 1mm with any ER chuck spindle size you use

Any ER collets you buy want to be in the .0002" or .005mm if not you are wasting your money

There you go ..another solution..just get a 1.0mm collet

[ericks]

Well....i have now given up trying to buy a Hertz spindle motor, i tried from Hertz themselves and one of their suppliers

[ericks]

After some issues i ended up buying two Hertz spindle motors....1.5 Kw and 2.0 Kw. I could not justify spending 170 euro shipping for just one spindle motor. Initially i was going to use a 0.75 Kw spindle motor but realized that it may be under powered for my router. So now my panel design have to change to accommodate for the increase in power consumption. I had to dump the PLC....and i need to add another main relay.

Lesson......plan and design properly and safe yourself time and money!

[e-motion]

Very nice Eric