Got a new toy and a question of collets

[Fazerruss]

Morning all, I picked this up yesterday from a member ( thank
you Frank you are a top bloke )


Well chuffed


I've been after a small cutter grinder for a while so this couldn't be missed.

Now as far as I understand these take U2 collets but the max size is quite small. I want a full set to sharpen all my end mills and I found these which seem to convert to a bigger size ER collets.
Will these fit and what's the difference between ER 25 and 32 holders? Is it just the max size the holder so you can have a wider range?

These I belive are the collets for my machine....


https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/371555448808

But I want to use something like these....

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/141936091124

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/141936092946

Thanks all

 

[Fazerruss]

Ps I will now be able to have perfectly sharpend tungsten's

 

[Wendelspanswick]

My milling machine uses U2 collets inside a 4MT holder, the largest collet is 17.5mm.
If you have a search on Deckel there is lots of information on these collets and the adaptors that are available.
The thing to watch with ER collects is the tool is held externaly rather than internaly so it's not as rigid and the distance the tool sticks out increases.

 

[Fazerruss]

So the ER 25 set should do me.
It seems the biggest U2 collet available is 18 mm and they are expensive and my end mills go up to 20mm.

I'm a bit green with other collets and tapers as everything in my workshop is either MT2/3 and my mill uses Clarkson Autolock collets and holder.

 

[Kram]

ER32 only holds 20mm. ER40 holds 26. The number is the OD of the collet holder and is bloody stupid way to name them.

 

[Wendelspanswick]

ER32 only holds 20mm. ER40 holds 26. The number is the OD of the collet holder and is bloody stupid way to name them.

My bad! I had always assumed it was the maximum OD of the tool it could hold.
I will delete my post!

 

[Fazerruss]

ER32 only holds 20mm. ER40 holds 26. The number is the OD of the collet holder and is bloody stupid way to name them.

Any idea what the OD of the chuck is for ER 32 collects?
Ideally I could do with it being under 40mm so I can slide the holder back to accommodate longer bits.

 

[KMP]

@Fazerruss The standard ER32 closing nut is 50mm outer diameter with a 40mm inner thread, the collet body if parallel will be 40mm. If you look at the ArcEuroTrade collet section it will show you the nut dimensions for the various ER ranges. As said earlier the ER32 is the smallest that will take a 20mm collet.

Keith

 

[Kram]

M40x1.5 thread for the standard. There is another type holder and nut ERx-M that might be smaller but have a different thread. Had a quick look I cant see any in the 32 size.

ER chucks stick out quite a bit. Looks like that tool has very limited travel. I would recommend them but it doesn't seem a good choice for this. Can you bore out the standard collet to 20mm?

 

[Fazerruss]

M40x1.5 thread for the standard. There is another type holder and nut ERx-M that might be smaller but have a different thread. Had a quick look I cant see any in the 32 size.


ER chucks stick out quite a bit. Looks like that tool has very limited travel. I would recommend them but it doesn't seem a good choice for this. Can you bore out the standard collet to 20mm?

The standard collet on this machine is only 16mm diameter so I doubt what I said earlier about max size of U2 collets won't be correct.
To have enough meat left I assume the max size would be around 14mm.
If I go ER 25 then hopefully the chuck will be small enough to clear the slider and then make a bespoke collet for 20mm end mills

 

[Agroshield]

The thing to watch with ER collets is the tool is held externally rather than internally so it's not as rigid and the distance the tool sticks out increases.

Could you translate the above to English please. I think what you are trying to say is that the gripping part of the ER collet is further from the spindle face than with a traditional collet.

We are talking here about a cutter grinder, where he will be removing a couple of thou at a time so rigidity is hardly a primary concern.

ER32 only holds 20mm.

FYI, if you look around it is possible to get up to 22mm ER32 collets. Sometimes these can get you out of trouble.

Any idea what the OD of the chuck is for ER 32 collets?
Ideally I could do with it being under 40mm so I can slide the holder back to accommodate longer bits.

You could make a raising block for the workholding part of the grinder (male dovetail on bottom, female on top - look at the one available for a Taig lathe for the concept). I don't know how this would affect where the tool is presented to the wheel. The raising block, if made long enough, may also help with the point below.

I think the biggest problem you will have is lack of length on the female dovetail on the lower part of the grinder. The back of the ER holder will be in front of the workholding spindle; with the cutter you are grinding bottomed out on the ER holder, you may be off the back end of the dovetail before there is room to get the cutter to the wheel.

I wonder if you could reverse the motor and use the other side of the wheel to gain some length.

Have a look at the various attachments people have made for Quorn grinders as something there might inspire you.

 

[Wendelspanswick]

Could you translate the above to English please. I think what you are trying to say is that the gripping part of the ER collet is further from the spindle face than with a traditional collet.

We are talking here about a cutter grinder, where he will be removing a couple of thou at a time so rigidity is hardly a primary concern.



FYI, if you look around it is possible to get up to 22mm ER32 collets. Sometimes these can get you out of trouble.



You could make a raising block for the workholding part of the grinder (male dovetail on bottom, female on top - look at the one available for a Taig lathe for the concept). I don't know how this would affect where the tool is presented to the wheel. The raising block, if made long enough, may also help with the point below.

I think the biggest problem you will have is lack of length on the female dovetail on the lower part of the grinder. The back of the ER holder will be in front of the workholding spindle; with the cutter you are grinding bottomed out on the ER holder, you may be off the back end of the dovetail before there is room to get the cutter to the wheel.

I wonder if you could reverse the motor and use the other side of the wheel to gain some length.

Have a look at the various attachments people have made for Quorn grinders as something there might inspire you.

The point I was trying to make was that with the original collets the tool is held within the bore of the spindle, with the ER collets none of the tool is held within the spindle, the whole length of the tool is held outside the spindle.
For instance with a 75mm long endmill you can have as little as 5mm sticking out of the spindle face with the U2 collets whereas with the ER system the minimum you will have sticking out from the spindle face is at least 75mm.
This means that when the spindle is pivoted the arc is bigger so fine adjustment is made more difficult and any play/misalignment is magnified.

Edit: Thinking about it with that amount of stick out you might not be able to achieve the correct angles of the tool to the wheel as it may be beyond the range of the machine.

 

[Fazerruss]

Sharpening end mills won't be a problem even with an ER collet protruding out further as there is enough clearance. As of yet I don't have any ball end mills so sharpening a radius is not an issue. I could always make a collet to suit that particular cutter when required.
I just don't fancy making a full set of collets as I have enough projects as it is so the plan is to buy a MT3 shank ER25 collet chuck and turn it down to the same size as the collet holder. I will then have a cheap set of collets to use for straight sharpening which is the main reason I bought this.

 

[Kram]

FYI, if you look around it is possible to get up to 22mm ER32 collets. Sometimes these can get you out of trouble.

Are these available to buy? I have a few lengths of 22mm so would be very useful. I knew its possible to grind them but not something I want to attempt.

 

[Agroshield]

Are these available to buy?

They must be as I have one. Mine came from China via eBay probably 6 years ago. You can also get oversize ER40.

Regofix sell them (but sit down when you look at the price)

http://www.allesguteusa.com/ecommerce/collet/er32-collet-individual.asp
http://www.ebay.co.uk/itm/Spring-Co...hash=item1e8a87e651:m:mxK0xTrn5B8r06-GipmW_dQ

Same supplier and still expensive.