Why would you choose either ER32 or ER40 collet for PM-1022V?

[ChazzC]

I was trying not to go into the weeds with non-standard thin wall ER collets. But here is a 26mm ER32. It's in the "use at your own risk" range of thin.

26mm ER32 collet

I’ll have to get one for my collection (I hope I don’t cut myself on the front & back edges)

EDIT: I received my ER32 26mm collet from Ali (ordered 10/5/24, so 10 days total travel time) and from an appearance perspective very pleased with it – no burrs and nicely finished. I also figured out how "they" make these oversize collets work:

https://www.hobby-machinist.com/threads/oversize-er32-collets-undersize-ones-too.114634/

And a 32mm ER40

Personally, I have a full rack of 5C. My main ER collets are ER20 and a few ER16 for my mill but I have not ventured into ER collets on the lathe at this point. When I do I'll probably set up some gang tooling on my cross slide using my existing ER20 collets and tools.

No sense in getting a 5C closer & set for my 7x16

 

[Aaron_W]

There are a few more tooling options for ER32 than ER40, but in recent years I've seen that changing. When I was collet shopping, 5C and ER32 were the only common type for collet blocks. Now you can get them in a variety of ER sizes. Spindexers are still pretty much limited to 5C and ER32.

Unless you really want a spindexer, I'd probably just go with ER40, as it is a little bigger and getting the ER40 chuck is an easier (and probably cheaper) option.

Collets are something that you will likely end up with a variety of, some serve different uses, and smaller collets are smaller. ER32 is my main collet size, but I also have ER16 as that collet chuck is about 1/4 the size of the ER32 chuck and on a small lathe that difference in size can make a difference.

 

[Larry$]

I should have added that I have some 5C collets with square and hex internal shapes. Bought for specific projects so I don't have the complete range. No idea if ER collets also come in various patterns.

 

[ChazzC]

I should have added that I have some 5C collets with square and hex internal shapes. Bought for specific projects so I don't have the complete range. No idea if ER collets also come in various patterns.

Haas sells tap collets but they only grip the square tail end of the tap. I know someone makes/sells a limited range of square & hex collets, but can’t remember who. I’ll add the link when/if I can find it.


Found it:

MariTool

 

[jwmay]

.

Having not found a need, or space for multiple sets of collets, I settled on ER40.

There’s not, to my mind, any significant trade off in choosing one over the other.

This stuff doesn’t have to be a scientific exercise in buying the most perfect setup ever. PM ain’t gonna steer you wrong.

Some of the advice you’ll get here is from the perspective of men who are running a business. Justifiably, they often have much, much more than the kit required for hobbyists.

 

[cneuor]

.

Having not found a need, or space for multiple sets of collets, I settled on ER40.

There’s not, to my mind, any significant trade off in choosing one over the other.

This stuff doesn’t have to be a scientific exercise in buying the most perfect setup ever. PM ain’t gonna steer you wrong.

Some of the advice you’ll get here is from the perspective of men who are running a business. Justifiably, they often have much, much more than the kit required for hobbyists.

As a novice machinist, I hope that I can rely on their decision. However, as other people mentioned, I see more accessories made for ER32, and I wonder why PM chose the other size. The same goes for their decision to go with the chuck mount that this machine has, which is not so common and creates headaches.

 

[jwmay]

I wonder why PM chose the other size. The same goes for their decision to go with the chuck mount that this machine has,

Aha, well…far be it from me to speak for a fellow member.

But if I were to guess, I’d say the ER40 goes to 24mm. And the chuck mount thing is a trade off to meet a price point.

Then after you’ve set up your inventory, it’s really just an expensive headache to change things that don’t really matter much to most buyers.

 

[m1kemex]

There’s not, to my mind, any significant trade off in choosing one over the other.

Of course there is and it's been explained along the thread. 5C collets have internal threads for a depth stop. They grip only on one side, so they can clamp very narrow parts.

Truth is that 5C are lathe collets and ER are drill / mill / grinder collets. They can switch roles to some extent, but they were designed with different purposes in mind: 5C to hold parts and ER to hold tools.

 

[Aaron_W]

Of course there is and it's been explained along the thread. 5C collets have internal threads for a depth stop. They grip only on one side, so they can clamp very narrow parts.

Truth is that 5C are lathe collets and ER are drill / mill / grinder collets. They can switch purposes to some extent, but they were designed with different purposes in mind: 5C to hold parts and ER to hold tools.

I think it is also worth pointing out that the collet tooling some of us mentioned being more widely available for ER32, is primarily mill tooling, not lathe tooling.

 

[WobblyHand]

I have an ER-40 chuck on my 10x22. I bought an ER-40 collet set from PM. I also added on to the set to go from 26mm to 32mm. The 32mm collet I use for 1.25" stock. I got the larger collets from AliExpress. They're not super awesome, but honestly, they are fine for my use. Haven't checked all of the large collets but the 32mm one is about 0.0005" TIR.

Using the Shars set tru ER-40 chuck. First one I received during the pandemic and it had a poorly machined taper. I took pictures of it and Shars agreed with me that it shouldn't be like that. Returned the bad one and got a good one. Very easy to dial in sub 0.0001" TIR.

Pretty sure PM has a similar chuck. I wouldn't hesitate to get PM's chuck.