Metric to Imperial Shanks?

Shopping for end mill bits. I see many are 4mm or 8mm shank. I have the 1/8" collet adapter for my DeWalt. Is there a way I could use those bits via some kind of converter or must I use only Imperial? Thanks!

Ex. The mm shank sizes on these bits.

Elaire Corp makes collets in 4,6 and 8mm

Dewalt Style Palm Router Collets

What do you think is the best step? Should I get a larger metric collet and then an adapter?
Basically it looks like 8, 6 and 4mm bits are more readily available / come in kits than 1/4" and 1/8" shank bits and I want some advice about how to build my collection of bits.

Thanks folks.

The metric shank diameter tools are less expensive and work great. But do yourself a favor and get the right size collets from Elaire. The adapters are nothing but trouble, when they work at all they add runout and when they don’t work the tool will either slide out or get stuck. Use the money you save on the tools to purchase the correct collets.

If you search eBay you will find lots of inexpensive metric end mills and vbits

Thank you! I’ve been trying to work in mm anyway b/c it’s easier to be more precise and simply logical. Glad to hear metric tools are also the right idea.

that funny bc i tend to feel that it is harder to find metric shank mills than imperial ones

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Most of the sets I see on Amazon are metric. I don’t have a car and there are no local stores, so I’m stuck buying online.

yup that is my experience too.
with 1/8 - 3mm you can force the collet though to fit both. With 1/4 - 6mm this isnt possible anymore…

Y’all are kind of confusing me now… which collets can I use for both? Which should I not buy? Should I do metric or imperial? These things are expensive and I’m trying to build a basic set of tools to make things to sell. I’m not at a point where I can be buying a bunch of parts. :confused:

start with an 1/8 collet

that is 3.175mm, so you can force it to hold 3mm bits too. Note that I don’t recommend it,but it is possible.
you cannot put 1/8 bits in a 3mm collet.

You can’t go wrong if you get a 1/8", 1/4" 4mm and 6mm. You can easily find any tool you will need in one of those shank sizes.