"SteveB" wrote in message
news:V0Qvd.28917$Ae.14761@fed1read05...
I am looking at Foredom tools to use them for finishing work on light
welds.
I will also be touching up the veining on stamped rods that look like tree
limbs. I need a tool that will use a wheel or cutter, and cut veins up to
1/8" thick, but mostly less. The welds I need to dress would amount to
1/4
to 1/2 square inch. Not a lot.
Does anyone have any suggestions as to which unit would be the best for
this. They come in all sorts of horsepowers and RPMS. A Makita grinder
is
14,000 rpm, and these go up to 18,000.
I say this from the perspective of one who has, and uses, three flex shaft
machines: Dremel, Foredom, Pfsing.
Yours is a heavy duty operation. The weak point of the Foredom tools (and
any other flex shaft machine) is that the flex shaft coupling springs
breaks -- twists off. You have to consider torque in addition to top-end
speed and a spindly flex shaft seriously limits torque. I don't know the
Makita but I assume that it caters to the die-grinder crowd. As such, it
will be beefy but the handpieces won't be interchangeable with the Jewelry
industry standards (see below). But you rarely go wrong with Makita. The
difference between 14,000 and 18,000 RPM is of little significance. You
can't really make good use of anything above 10,000 without some kind of
coolant. Also, sustained high-speed operation overheats the coupling, the
handpiece, the bearings, and leads to premature wear. I've never had a
motor burn out. I almost never go full-throttle on my flex shaft machines.
Slower speeds with good torque are probably more important than top speed,
unless you're planning to do a lot of dentistry.
Should I just bite the bullet, and go for the big one since it has a foot
pedal to vary the speed and compensate for different work?
A flex shaft machine without a foot pedal is almost useless. If you're
budget limited, go to the sewing machine store and plug your Dremel into a
sewing machine foot pedal. The Dremel has an AC/DC motor so the cheap foot
control works just fine. Lot cheaper than Dremel's foot control.
Would the smaller ones like 1/6 or 1/8 hp be an invitation to burnout?
Not merely an invitation, but a guarantee.
Or would a top of the line Dremel be acceptable?
Not a chance. Good high-speed performance, but really funky with respect
to collets, chucks, etc. A Dremel is what you get if you can't afford to
buy a Foredom or other professional grade flex shaft machines.
How about replacement tool cost comparisons?
With Dremel, you're stuck with the Dremel handpiece and chucks and almost
nothing worthwhile comes on the used tool or auction market. With Foredom,
you have a wide variety of handpieces. You can't use 1/4" tooling with the
dremel. Serious limitation. As for bits, burs, saws, grindstones, sanding
and polishing discs, etc. As long as you have a good handpiece with a
variety of collets, you buy these almost any place other than at a Dremel
retailer.
I suggest you consider the following handpieces:
1. Big collet chuck handpiece for 1/8 to 1/4" tooling. Essential for what
you're planning. 1/4" tooling is generally cheaper than equivalent Dremel
tooling.
2. A Jacobs chuck ball bearing hand piece -- good for everything else and
high precision.
3. A quick-change collet chuck if changing bits becomes a bother.
4. A hammer -- used by diamond setters to set prongs, but you might find it
useful.
The nice thing about the Foredom and other top-of-the-line flex shaft
machines is that there is an industry standard for the hand pieces. They
are interchangeable -- push-pull, click-click. Foredom (and others) make
about 20 different kinds of industry-standard handpieces. I've bought
junky, burnt-out, flex shaft machines just to get the handpiece.
Boris
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