Rotary (Moto) Tools

Moto tools are an excellent aid to modelers.  In many instances they make cutting, grinding and sanding faster and more accurate.  The reason I purchased my first Dremel tool was because I had nothing that could cut music wire.

The downside to moto tools that the bits are expensive — especially when you are starting out.  It never gets any better because the bits do not last very long.  Garnite bits wear down and steel bits become dull quickly.

In spite of these shortcomings, moto tools are excellent and great time savers.

Also see

• Power Tools for Model Building
• How to Make a Router/Shaper Table for use with a Moto Tool

Safety

Always wear eye protection when using a moto-tool regardless of the accessory you are using.

High-speed rotary tools can be very dangerous!  Anyone who has ever used an emery cut-off wheel has seen one shatter.  The pieces get thrown everywhere.  I can not count the number of times I have had a wheel shatter.  This is usually due to putting too much force on the tool or putting a side load on the wheel.

Another dangerous accessory is the wire brush.  These are either brass or steel, but they both present the same hazard.  Specifically, the wires break off and get thrown everywhere.  They get under the skin very easily and can also be thrown into your eyes or other places where you do not want them.

Rotary saw blades will cut through your skin like a hot knife through butter.  Be especially careful of these tools.  Never hold the tool in one hand and the work in the other.  Always secure the work and hold the tool with both hands for maximum control and safety.

Lastly, if a bit is out of balance, you will know it because the bit will not turn true and the tool will vibrate.  Usually you will hear the bearings complain in the form of a nerve-shattering screaming sound.  Unbalanced bits will destroy the bearings in a moto-tool very quickly if not instantly.  The larger in diameter the bit, the more critical it is to make sure it is balanced.  Use a dressing stone to bring garnite-type bits into balance.

Moto Tools

I have used variable speed Dremel models for years.  A problem with the corded tool is that for some materials is too powerful and cuts too fast even on the slowest speed.  This can cause wood to burn and plastic to melt.  Bits heat up quickly and long before the job is finished.

The smart thing to do is let the bit cool periodically before it over-heats, but that can make some jobs take a very long time.  An over-heated bit can lose its temper and become dull almost immediately.

I purchased a Mini-Mite (bottom of photo) also made by Dremel.  I use it much more frequently than the full sized models because it is less powerful.

Due to its lower power and lighter weight, I have better control of it, mis-cuts are less likely and it is less likely to melt plastic.

I mainly use my moto-tool for cutting with a circular saw blade and emery wheels, sanding with a sanding drum and routing.

Other hobbyists use moto-tools for carving and other types of wood work that really are not applicable to the kinds of models I build.

Chucks, Collets and Accessory Bits

Every Dremel tool I have purchased has come with their standard chuck and collet assembly.  While it works just fine, it isn't real convenient and it's not very versatile.

The tool comes with only the 1/8" collet which works for 95% of all bits made for rotary tools.

Some smaller bits have 3/32" shanks which means you'll need to purchase the 3/32" collet.  At some point I purchased all the collets.  There are four different sizes as shown here.

I don't know what the actual size of the smallest collet is but I've yet to have a bit so small that the collet couldn't hold it.  The other two sizes are 1/16" and 3/32".

At some point a Jacob's style chuck became available.  Unfortunately it doesn't fit every model Dremel model because of the randomly chosen housing style which is a Dremel standard.  See my tirade further down this page.

The Jacob's chuck rubs against some nose pieces and can't be used.  I actually have two different Jacob's chucks.  Some of my Dremels can't use either one.

I wouldn't use a Jacob's chuck on a corded model anyway.  They are designed to be hand tightened and I think it's a safety risk to use this type chuck in a more powerful model.

I do use Jacob's chucks in both my Mini-Mites.  It eliminates having to change collets.  It doesn't close far enough to use micro drill bits which is why I have the chuck adapter shown at the bottom of the above photo.

It used to be that you could buy a Dremel tool without any accessory bits.  I haven't seen it sold that way in a while, but if you can find the tool without bits then I suggest you purchase it that way.

Dremel says you get <insert number here> accessories with the tool, but most of the accessories are not real useful.  For example, you may get 25 sanding disks which count as 25 of the 60 or however many accessories.

On the day you die, some lucky descendent will receive 24 of those disks in brand new condition.  There are probably only a couple accessories in the package you will actually use and you will save money just purchasing them separately.

There are other manufacturers who make accessories that fit moto-tools giving more choices.  It pays to shop around.  I have a nice set of bits for a moto-tool.  When I got my new Microlux drill press, I needed to play with it of course, so I made a little holder for my bits from a scrap of press board.

I do not use the emery grinders very often because I do not really have a use for them and when I do, the job is usually too big for a Dremel.  Actually, the Dremel can handle it, but the grinders wear down quickly.

The bits I use the most are sanding drums, cut-off wheels and rotary saws.  The straight router bits get used fairly frequently as well.

On the left is a saw set made by Gyro.  It was a fairly expensive set, but it is a one-stop shopping thing.  You get everything shown in the image in one package rather than paying even more for them individually.  The blade I use the most is mounted on the mandrel (top left).

Dremel Tirade

Dremel comes out with a new moto-tool model every couple years that is not compatible with their old models.  The new model never fits the old accessories (drill press, router base, etc.) because for some reason each Dremel model has a different shape housing than every other Dremel model.  Can anyone tell me what's wrong with round?

The adapters that are supposed to make any given housing compatible with various accessories such as the drill press, router base, etc. are cheap, soft plastic that not only don't fit very well, but they aren't very secure either.  In every case that I've used an adapter, the Dremel could move easily even when fully tightened in place.

In addition to this the accessories I have purchased (drill press, router base and a few others) haven't been very accurate and usually had a lot of play or were too flexible.

I bought their drill press many years ago and it had so much slop and play in it that it was worse than drilling by hand.  There was not a built-in way to adjust it.  It was made to fit the moto-tool model I had at the time.  I can only imagine how much worse the situation would be if I used one of their equally bad adapters with a new model in the old drill press.

My moto tools have not lasted as long as I think they should.  The bearings wear out quickly and are expensive to replace.  I used to abuse my Dremel by always running the tool at full speed and using bits that weren't balanced.  I can't blame Dremel for that, but since then I've been very careful to use the tool properly at the lowest appropriate speed for the task and by either balancing the bit or not using bits that couldn't be balanced.

The bottom line is that I am really frustrated and aggravated from buying a new tool every couple years and having all their expensive, poorly made accessories become obsolete with each new model.  I have not found their support to be very helpful in resolving any of these problems.  Repairs are expensive and slow.  By the time the repair is paid for, I've paid 60% of the cost of a new tool.

When this one dies, I will take a good look at the offerings from other companies (by the way, the Craftsman model is a Dremel in disguise).  I love moto-tools, I just do not care for the poor quality tools offered by Dremel.

Personally, I would pay top dollar for a high end moto tool having the best bearings available.  I want the housing to be round so that accurate bases can be made in my shop or by third party manufacturers.  I think a good moto tool housing could be made from aircraft aluminum tubing.

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