Problems with a Dremel

[Stone]

Yesterday I went out and bought myself a Dremel. This One. It came with a free engraver, a flex shaft a planer and a lawn mower blade sharpener.

So I was playing with the different bits I got (70 or so) and I decided to put a cutting blade on They don't have a shaft, so with a little research I found out I need to use a #402 Mandrel. This is where the problems started to arise.

I quickly found the mandrel, inserted it into the dremel, and I figured I just took the screw off, then screwed the cutting disc onto the mandrel. So I tried to take the screw out, but the entire thing just kept turning. No matter how much I tightened it. So, I took it out to the garage, and put it in a vice. I got the screw out, well, the screw head and about a millimeter of the screw shaft.

So now I have a broken mandrel, and no way of using the cutting discs, sanding discs, or polishing disks, until I go and buy a new mandrel bit. I won't be going back to Home Depot until tomorrow though, so I wanted to ask if screwed the head of the mandrel was the right thing to do, or if there is some trick to getting it off? I searced google, but all I found was a bunch of places selling the #402 mandrel, not how to use one.

So, my question is, how to properly use a #402 mandrel, with a cutting disc. Any help is appreciated

[.Maleficus.]

Do you have any pics of what you mean? I'm sort of confused on what happened.

[alexanderH]

I personally have never encountered such a unit. But it sounds very similiar to what I had come with my craftsman rotary tool. And I busted it to the same degree you did. Couldn't find any help, and fankly it seemed stupid that such a device would hold so many different tools. So I went out and bought a tool specifically for cutting discs, made by dremel with no screws involved. But for the other tools I had to get one with a screw in it, and I showed the guy at the hardware store and said that it can happen to them when they come in the box. But I replaced it with the piece you got, the 402 and had no problem with the new one. Even in a craftsman all you do is unscrew the screw, had to use a vice the first time but be gentle. And then place your tool and replace the screw.

[crazybillybob]

The craftsmen rotary tool is a Dremel XPR (just diffrent color )

What happened is that you over tightened the little screw... Not the first ones to do it either Here's a trick use the smallest diameter screw driver you can find when you tighten down that screw (why?? because the smaller the diameter of the screw driver the less leverage you have on the screw head, and the looser the screw is...get the idea) You really only want to snug the screw up, that means run the screw in until it touches the cutoff wheel, and the cutoff wheel touches the shaft (the screw should be a tad tighter to turn..not much just a tad) once to that point tighten it no more then a 1/4 turn this will keep you from cracking cutoff wheels and breaking the screw. Also after you've been cutting for a bit that shaft and screw heat up..this will make them expand and get tighter, so before you unscrew it..let it cool down a bit (if your in a hurry, grab hold of the shaft with a big pair of pliers for a couple of minutes to speed cooling). Follow these simple rules and your mandrel will last 10+ years (I've got one that is 15+ years old Yes I'm one of those "Old" guys around here )

Good luck!

CrazyBillyBob