I have a brand new Ryobi router model ERT241200. Am I supposed to insert the 1/4'' collet into the cavity where the collet nut is, then insert the bit into the collet and tighten the collet nut? I thought this was the obvious thing to do, but the collet does not fit in the cavity - it (ie the collet) is slightly too big. Am I supposed to apply a lot of force and tap/punch it in? I have not found the manual helpful on this point. I am new to all this and any help would be greatly appreciated!

There are 8mm to 6mm adapter sleeves available. If you take the collet along to a power tool store they may be able to supply you with a suitable 6mm collet. I can't find what type of collet is in the router, but I'm betting it is a ER-11 type in that size range.

https://www.maritool.com/images/ER11-Collet-1.jpg

Hello there
Seems like the RE175 manual is not longer available at Ryobi.

This is from the manual for the RE180 which MUST be similar to the re175. Manual download here https://manuals.ttigroupna.com/system/files/5849/original/RE180PL1_448_trilingual_05.pdf?2014

From page 7 ....To remove the bit:

Place the wrench provided through front of router base
onto collet nut and turn counterclockwise to loosen.

Loosen the collet nut and remove the bit.

Release the spindle lock

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On some models the collet stays put on purpose. You don't have to remove the nut either. But if you really do have to remove the collet and it is the type that is supposed to come out (maybe you need to use the 1/4 inch collet) then just stick a bit into it without the nut and give the bit a sideways whack with a piece of wood. If the collet has been pressed in tight by the nut without a bit in place, then you won't be able to fit a bit into it, and maybe the collet is ruined. Find the largest diameter shaft you can to fit into the hole and pop that sideways. Good luck.

Have you tried taking out the collet and cleaning it and the cavity where it goes? If there is any wood dust present it may be causing the problem. If that doesn't fix it, you may need a new collet.

Get a new collet and nut the 1/2" collet is crappy, it is too thin and pushes out of the nut easily.

You may also make sure that the collet did not seperate from the nut. remove the nut completely and if the collet is not attached, remove the collet from the spindle, insert inthe nut and then insert the bit through the collet while holding it and then put the hole thing back on the spindle (mtor shaft) and tighten it.

I would suggest going to Dewaltservicenet.com and typing in your model number for an owners manual for this tool. If you still need more help let me know and I will try.

Collets can be found on amazon, here: Amazon com craftsman router collet. I hope this was helpful. Cheers

could be a couple things. First how is the shank on the bit e.g. is it worn down, second is it the right size for the collet being used (have to ask) and what is the condition of the collet and collet nut. What I would do is make sure there is nothing to prevent from completely tightening the collet nut. Also make sure if the collet locks into the nut that it is properly installed. Lastly make sure that you use the wrenches provided to tighten the assembly. If this doesn't help please provide the model number and brand and I will do some more research.

You have, I presume, already locked the spindle and loosened the collet nut with the wrench, have you not?
Once the nut is loose, you should be able to remove it by spinning it off the threads by hand. Then insert the 6 mm collet cone into the collet,
carefully thread the collet nut back onto the collet, and tighten it with the bit in place.
Sometimes bits are a snug fit, especially into a new collet. If you have some fin sandpaper you can gently chamfer the very end of the bit where you first insert it into the collet, and this may help to insert it. If you have to, push a bit.
I have noticed that some companies tend to mill the shafts of their bits a little too close to the exact tolerance, or even oversize them slightly, and this can cause frustration when inserting their bits. In exceptional circumstances, I have resorted to polishing a couple of small bit shafts with very fine (600 grit or so) emory cloth, just to allow the bit to enter the collet. I would not recommend this with a new router collet, unless you have checked the bit with a micrometer and it is oversize. Odds are you just need to break things in a little.
The force need not be brutish, but you may need to use some force, yes.

If I've managed to answer your question or solve a problem, please take a moment to kindly rate this post....thanks!