How can insert CNC Drill bits in Makita MB3700B

Hi Everyone,

I brought new MB3700B trimmer and I find CNC drill bit can’t fit in collect/nut of trimmer so there are adaptor for small CNC drill bit to fit in?

See picture of different size of CNC drill bit and Trimmer drill bits

https://shop.v1engineering.com/collections/parts/products/makita-1-8-collet Ryan sells it, it is from Elaire Corp. Does this fit your router?
Otherwise check out https://www.elairecorp.com/ directly, they might be able to make a custom one.

@Tokoloshe 's suggestions are good ones assuming your router takes the same collets as the RT0701C. It probably does, but you might want to do some research first. And I believe the MB3700B comes standard with a 6mm collet, so you might be looking for a 3mm collet. I don’t know if the 1/8" collet Ryan sells will handle 3mm shank bits. Note that they make 6mm shank bits in smaller cut sizes and even tapered bits with small ball ends. Not ideal, but they might get you up and running until you can source a smaller collet.

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I found internet to order in South Africa, ER20 Collet

link: https://www.gadgitechtrading.co.za/products/er20-collet?_pos=1&_sid=d87853c23&_ss=r

So how can I put this E20 collet 3mm adaptor into Makita trimmer?

I don’t think this is what you are looking for. Take the nut off the bottom of your spindle and pull the collet out and see what it looks like. Others on this list can give you better information, but I think Makita routers need some sort of conversion to use ER-style collets. A quick search yielded this web page with a breakdown diagram of this style of collet and some information on the conversion:

Hi Chris,
I know this is a 3 year old post and I hop that you ended up working this out? I know this is an old post and not sure if there is another thread for the same question/issue. But I have found myself here when trying to also sort out this delimena and for anyone else that is finding this thread I would like to offer my solution. I have both the Makita 3700B and the RTO700C, they have very different collets
Screenshot 2023-10-27 224153
The 3700 uses the cone collet (right) and the one on the left is used by the RT0700C and other (RT0700CX3, RT0701C, RP0900K, 3621, 3621A). In your case Chris, I would choose the following Collet Reducer from the website you linked.

I found a similar product here in Australia and it works well. But I wanted to be able to use variable speed so I bought the TR0700C and the reducing collet from Ryan’s shop @vicious1

Hope this helps others whom stumbles accorss this same question.