[Sammy62]

Hello,
I am new to the forum. I just introduced myself but I am not sure it went thru, as I also filled our my profile and at the end did a save but I don't see any of my details
Here is my problem:
I bought a Bosch 1617 evs about 3 weeks ago. Installed in home made table. I noticed immediately that as I loosen the collet (1/2 or 1/4) that after 1 to 1-1/2 turns it binds again and I need use the wrenches again until it passes this hard spot. This happens on both 1/2 & 1/4 collets and whether I am tightening or loosening the collet.
Is this normal on this type of collets?
Thank you for your help in advance.
Sammy

 

[gdonham1]

Sammy what you are experiencing is normal. When you loosen the collet on porter cable and the Bosch, if you just loosen it a little you cannot get the bit out. You will keep turning with the wrenches and you feel it give. That second give is the collet releasing from an incline plane that tightening pushed it into. The Collet is a kind of W shape. The shaft on the bottom of the router has an inclined plane machined in to it. so as you tighten the collet is compressed and pushed down the inclined plane, locking the bit in the mechanical grip of the collet. Loosening the collet allows the collet to relax and be pushed back up the inclined plane and releasing the bit.

So the short answer is yes it is normal to have to loosen then keep loosening until the bit becomes loose.

I just bought a replacement Bosch 1617 EVS to put in a CNC Router. The old one sounded pretty ragged and there is a big nut at the bottom of the base around the shaft that holds the bearing in place. That nut has the edge chipped off. Since the CNC Router needs a smooth cutting router I got a new one from Amazon. The original router did not come with a base and I took the new base and put it on the old router and will use it if I get a nasty job that I just need a through down router for.

Good Luck

 

[sreilly]

As Chuck said this is the norm for all my Bosch routers that I have. It took me a while to get used to that as my old Craftsman routers, which I haven't used in a very long time, took just loosening the nut with the wrench and then you could finger turn the rest as I remember it.

 

[Sammy62]

Thank you both for the quick reply.
Actually, I was going to remove the body of the router from its base and inspect the threads on the shaft that mount the collet
I am glad this is normal. I didn't want to have to return this router. I like to way it starts and smooth running.
Thank you again
Sammy

 

[Stick486]

Sammy...
welcome to RF... glad you made it..

while yur rummaging around stop in at this link for some light reading...
you'll find a lot of information there on your collet...

 

[DesertRatTom]

Welcome. This spooked me a bit when I got my first 1617, but it's normal. Do take some time are read the material Stick posted. It's good information to know and will increase your safety. You can also use it in a table, lots of information in here about making your own table. All in addition to the CNC.

 

[MEBCWD]

Welcome to the Router Forums Sammy. Hope to see you post a few projects using your new router.

 

[RickKr]

You've had the explanation of what is happening. The router collet is one of the types that is referred to as "non-self releasing". Morse Taper (MT) collets and inserts are also non-self releasing. Many machine tool collets are "self releasing", such as 3C, 5C and R8, which are used in the spindles to hole parts being worked, or in the case of the R8 in milling machines, to primarily hold the tool/cutter that is doing the work.

I'd not thought of it before, but it may be helpful that the router collets are non-self releasing. Gives me a chance to grab the bit before it falls down into the cavity, not that there is far to go.

Rick