Evaluations of the Mutual Power Alpine 6500:
Richard Lucas, November 14, 2005:
Place of purchase: Mutual Power
Date of purchase: 10/2005
Warranty: 5 years, 1 year on electronics
Electronic rotational tensioner, 6 point mounting, 2 glide bar clamps, upright unit
As background, I've been a CS since 2001, and used an
Alpha Revo 3000 before I got this machine. I currently go to college and don't find a lot of time for
tennis at the moment, but I still get out whenever I can.
I ordered the machine on October 17, received it a week later. It came with a number of hex keys, tools,
12 sets of string, 2 wrenches, and 2 instruction manuals, one for the tensioner, and one for putting the
machine together and some basics on stringing. I disagree with the part of the manual that basically says
it is okay to double pull. Again, this isn't a huge issue with me because I already know how to string
but it worries me for someone who buys it as their first machine and uses only the manual to learn. Put
it together that night (took about 45 minutes), but didn't have a chance to string on it for a few days.
When I received it the brake was closed extremely tight and it was necessary for me to use a vise-grip
and a wrench to loosen it. Once that was done the brake works fine. There was a small issue with the way
the tensioner fit onto the bar that is normally used for a crank tensioner. Basically, the tensioner is
held against the bar using 2 bolts. The bolts were a bit too short, so the tensioning unit would lean
back a little. I cut up an old mouse pad to take up the space and now it stands up as it should.
Once everything was set up and plugged it in and checked the tension. Pulled at 60 lbs. just like it was
set. Now for the review.
Similar mounting to what I was used to from the Revo. Basically it holds inside the frame at 6 and 12,
and has 4 mounting arms that hold on the outside. Nothing really different here than the standard. This
machine uses K-shaped supports instead of the V-shaped that the Revo had. They appear to be a little
sturdier than the V-shaped supports. The supports occasionally cover a grommet making it a bit more
difficult to reach with the string, but this is pretty much unavoidable with this style of mounting.
The knobs don't catch the string as much as the knobs on my Revo did. The mounting post on one side is
stationary and the other side can move back and forth to allow for different sizes of frames. This is
moved by loosening three hex screws, moving it, and then closing the screws again. This could potentially
be a pain if stringing a number of different frames in a row, but for me is no problem. The posts can be
adjusted up and down for height as well. Obviously you can change them too much or the clamps won't be
able to hold the strings. These are also adjusted using hex screws.
These appear to be basic glide bar clamps. No diamond dusting, just small grooves in the teeth. I doubt
that helps with gripping the string and I would have preferred if they weren't there, but they are. After
a quick cleaning and a few frames, the clamps glide along the bar with ease and hold tension perfectly
well. I'm still getting used to the glide bars but I am liking them more and more with each two-piece
string job I do. It is a bit annoying to have to move them 3 or 4 times when doing an ATW pattern. Still
pretty easy to use and I'm starting to get the hang of them. I will need a few more frames before I'm
completely comfortable with them to the point that I was at with the Revo dual action clamps. Originally
the clamps used a small nut that had to be adjusted by a wrench to tighten the clamps. These are set down
into the clamp a bit, so a wrench could not be used normally, it had to be put in perpendicular to the
clamp in order to adjust them. I switched out these nuts with simple 6mm wingnuts so I can adjust
them by hand. It really helps out a lot and doesn't annoy me nearly as much as the wrench method.
I'm still considering switching to Neos clamps, but I may not do that for awhile for a number of reasons.
According to the guy I talked to from Tennis Machines the Neos clamps are about a half an inch shorter,
which means I would have to move the mounting posts down, but it is still a viable option. Neos clamps
are $65 each plus shipping, so I'm hesitant to buy them unless I'm absolutely sure they will fit.
While the machine is sold as an "electronic" it is more like a rotational lock-out machine.
I have yet to notice it pull on the string after initially reaching the set tension. Earlier today I set
the tension to 60 lbs. and had it pull tension on my calibrator. I left it there holding tension for 20
minutes. I checked on it periodically to see what tension it was at. I also checked to see if the
rotational tensioner had rotated past the point where it originally stopped. After the 20 minutes it had
not moved anymore. To me, this is not a big deal because I am used to a lock-out machine (this machine
produced a slightly stiffer string bed, but not as stiff as a true constant pull machine). It took a
slight 2 pound adjust to get to the same feel I got from the Revo. Over the 20 minute test earlier today,
the tension read by the calibrator dropped to 56 lbs. after the 20 pounds. While the tensioner does not
appear to pull on the string after the initial tensioning, the tension is still consistent and produces
consistent jobs. If constant pull is of huge importance for you, then this is not the machine for you.
The tensioner can be set anywhere along the bar, I have the tensioner set as far back on the bar so that
I have 360 degree racquet rotation. This means that I need more string to reach the tensioner, but the
racquet rotation is nice to have. I'm considering eventually upgrading to the Wise tension head, but
again, money is not something I have at this point. Overall, the machine does its job very well. The
machine is not perfect, but it does what it is supposed to. Overall, I am happy with the machine. By
placing the tensioner on the bar, it gives me the option to change it to a crank machine, or add on a
Wise tension head later on. If the Neos clamps do fit, there is the potential that the machine would
have Neos clamps, Wise tension head, and a quality mounting system for around $1300. Even without the
upgrades the machine is still of high quality and I am pleased with my purchase. If I had more money
to spend, I likely would not have even considered Mutual Power, but I do like the machine. With more
money I would have probably gone with either a Neos or a high end Gamma or Alpha, but for the money
that I spent, I'm extremely happy with the jobs that I can produce.
Note that the information on this page reflects the personal subjective opinion of the evaluators. If you disagree, please send in your own opinion.