Should I care - 6.5mm instead of 1/4" DA collet

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ctwo
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Should I care - 6.5mm instead of 1/4" DA collet

Post by ctwo »

I bought a nice used 180 DA collet set 1/4 to 3/4 in 32nds. The 1/4 is actually 6.5mm. It might work but obviously loose.
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Rich_Carlstedt
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Re: Should I care - 6.5mm instead of 1/4" DA collet

Post by Rich_Carlstedt »

Many Collets have a .015 range .
6.5 mm Is .010 larger than .250" ~ so you should be fine
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ctwo
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Re: Should I care - 6.5mm instead of 1/4" DA collet

Post by ctwo »

The Kennametal catalog says this system max collapse is 0.005". 6.5mm is actually 0.006" larger and that is what is measures. This is an Erickson branded collet. Parlec specifies 0.016" max collapse.

It seems to hold and has typical runout that I get, 2-5 tenths. I was just worried about it spinning or cracking eventually. Maybe less likely with the smaller sizes?

Some sites only recommend them for drilling, but I still plan to use them for milling too, just taking it a little lighter.

I hate to be the guy that complains but he listed all of the individual sizes and could have said it was 6.5mm, and it wasn't particularly cheap.
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Re: Should I care - 6.5mm instead of 1/4" DA collet

Post by Rich_Carlstedt »

When I said Range .015, I meant collapse only .
You never want to go oversize
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ctwo
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Re: Should I care - 6.5mm instead of 1/4" DA collet

Post by ctwo »

You never what what to go oversize?

I am actually now thinking the larger sized collets, like a 19.25mm collet in place of a 3/4", would fair better than a 6.5mm collet in place of a 1/4", because there are more slits and fingers to flex and hold.

Or I'm overthinking it. It's just that 1/4" and 3/8" are my most common cutters in this system.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
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ctwo
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Re: Should I care - 6.5mm instead of 1/4" DA collet

Post by ctwo »

Well, this is no good. I contacted the seller and requested a partial refund. They refunded me the entire purchase and told me to keep them. Now I have to fix this.
Standards are so important that everyone must have their own...
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Mr Ron
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Re: Should I care - 6.5mm instead of 1/4" DA collet

Post by Mr Ron »

ctwo wrote: Tue Jan 12, 2021 5:07 pm Well, this is no good. I contacted the seller and requested a partial refund. They refunded me the entire purchase and told me to keep them. Now I have to fix this.
What a deal!
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Re: Should I care - 6.5mm instead of 1/4" DA collet

Post by Lew Hartswick »

:-) "DA" was a haircut style. The first thing that comes to mind when I see it. I really hate abbreviations that aren't accompanied by the full description the first time they appear.
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ctwo
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Re: Should I care - 6.5mm instead of 1/4" DA collet

Post by ctwo »

It wasn't really the kind of outcome that makes me feel totally warm and fuzzy inside...

I think I made a technical error in how I presented what these collets are. I think they are properly called DA180 collets. I am sure that at clears up the confusion.

Apparently, ER collets are the most widely used clamping system today. I discovered that the R stands for Rego-Fix, who patented the design. The letter R was appended to the universally known E designation, which I've not heard of, but if I did, I might have thought ER was connected the very popular R8 collet, but there I do not know what the R stands for, much less the 8. I am surprised that ER collets are more popular than C5 collets, which I would have almost bet money on being the most widely used. Besides me, who doesn't have a set of C5 collets and a couple of those collet blocks?

It did not take me a long time to find out what DA stood for, and that is double angle, which seems fitting. I could not determine what the numbers mean, however. There are several sizes, such as DA200, DA300, etc. I also have a set of DA200 for smaller tools.

This was all good because now I know what a D.A. haircut is.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...
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