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On another thread, Barry Daniels posted a link to precisebits.com. I was looking for something else when I came across this.

http://www.cncsharktalk.com/viewtopic.php?f=9&t=785

It's about runout in newer production lots of the Bosch Colt. I have not check my dates yet. I'm thinking all of my stuff is pre-2011. Has anybody experienced problems with their Colt? I have three and would be seriously stressed if this were my case. Clearly, I have not had issues. But I still want to test them.

Mike

go look at simon fay's post in the classifieds. he is selling his and has lots of info regarding runout

Zeke, thanks for the tip.

Mike

Figures, I just purchased a Colt right after Christmas. Clinton

I've got one and I love it. No problems here. And for what I use it for it could have .01 runout and never cause me any issues. I mean this is wood it moves and changes with the weather I can't see where a few thou runout would effect anything. At least not for me. I don't use the router for anything super precise.

The issue isn't as much with the wood moving -- runout will effect the actual cut of the router. It is the same principle with a drill. The general rule is the you don't want more runout than 10% of the diameter of the bit -- this means that for very small diameter bits, you need almost no runout. The runout can come from the collet, poorly tapered spindle, bad bearings, and other things -- although, the things listed are usually the first things to check.

In my limited experience, Bosch collets are just poorly made in general but are otherwise, very nice routers. If you can source a precision collet for them, they are a great way to go. Also, collet reducers introduce a lot of runout -- and so, even a good collet + reducer is probably going to be problematic for very small end mills (1/32" and smaller). For bits bigger than that, then you have a wider tolerance range regarding acceptable levels of runout.

I used to have a Colt--and as has been said elsewhere, the stock Bosch collets aren't great. I had a fair amount of runout in mine, but when I replaced it with a Precise Bits collet, things improved a lot--runout wasn't as good as it is on my dental handpiece or my Colombo spindle, but still quite good. I routinely ran fairly tiny carbide endmills in it and didn't have a problem with either precision or bit breakage.

From my experience, the problem wasn't nearly so much in the router as it was in the collet. An easy fix. I thought it was a nice little router. I was using it on a small CNC machine and sold the machine or I'd still probably have the Colt. This was a 2011 model Colt, so things might have changed since that time.

Dave

Understandable simon. Its just that I personally dont do anything requiring that sort of precision. I dont use any real small bits in my colt anyway, I use the dremel for that and it seems to get the job done. I spend all day as a machinist dealing with tight tolerances, so when its time for guitarbuilding I like to leave the stresses of high precision behind. I can see how the runout can be an issue for some, just not for me. I really havent noticed much runout in mine either. Cuts pretty true, but then again Ive never tested it. Maybe I got a good one Any how I do appreciate you bringing this to everyones attention because for some this could be a big issue. For others not so much. Looks like maybe these manufacturers should stop importing the overseas junk and get some quality american made parts (I used to make a lot of stuff for power tools, these days not so much. I cant compete with chinas prices. I just dont understand why my employees wont work for the same pay as a 12 yr old chinese boy. Oh well )