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Macrograb B52 Version A
Macrograb B52 Version B
Micrograb B53
Micrograb B53A
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| Macrograb B52 Version A | Macrograb B52 Version B | Micrograb B53 | Micrograb B53A |
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I acquired my Macrograb, Version A from On Rope 1 in September 2000.
My Petzl Macrograb B52, Version A is 114 mm. long, 92 mm. wide, 51 mm. high, and weighs 336 g.
The Macrograb looks and functions like a Type 1 Lever Cam Ascender, but it is marketed as a rope grab. The frame is milled from aluminum (much like the Rock Exotica ascenders). The rectangular-shaped rope channel is 20 mm. wide. The inside of the shell has a milled depression that the cam forces the rope into. This spreads the load on the rope, and may increase the holding power of the ascender. It is claimed to help reduce rope damage under shock loading, but I can't confirm this. Rock Exotica pioneered this feature, and Petzl acquired it from them.
The cam has 5 rounded teeth, and is held by a cable keeper that doubles as a spring that applies a significant closing force to the cam. The keeper is attached to the cam by a small set screw. The cam axle is an 8 mm. Allen-head cap screw secured with a lock nut. The top of the rope channel is rounded off so that the rope does not bend over any sharp corners. In addition to the axle hole, the frame has three small holes. One is for the keeper, and a second, drilled from the side, accepts an set screw to hold the keeper in place. The third hole, through the back of the frame, does not serve any obvious purpose.
The front of the frame is stamped with an arrow pointing up,
the Petzl logo, "12≤Ø≤19mm,"
"1/2"≤Ø≤3/4," "
"EN567," "CE 0197," an icon showing how to
rig the cam, and Petzl’s Reading-Is-Dangerous icon. The rear
of the frame is stamped with "001966" which I assume
is a serial number or date code. The frame spine is stamped with
"USE ONLY APPROVED 12"-3/4" (12-19mm) SYNTHETIC
ROPES," "CHECK UNIT BEFORE EACH USE," and "REMOVE
FROM SERVICE AFTER SUBJECTED TO LOAD OR FALL." The rear of
the cam has an arrow stamped on it, I don't know what it intends
to show.
Remove from service after it’s been loaded once? Are you kidding me? I understand for a hard fall, but not for a simple static load. Why do Doctors let Lawyers live?
The Macrograb is a clunky-looking device. Its a shame that Petzl couldn't round the inside of the rope channel, after all, most of us use round ropes instead of square ones. The cap screw axle is a cheap way to mount the cam, and it makes it excessively difficult to put the Macrograb on rope or take it off. Petzl supplied a 5 mm. Allen wrench for the cap screw but forgot to provide a wrench for the nut. This is rather surprising, since they included a 2.5 mm. Allen wrench to remove the two screw holding the cable to the cam and frame! It really doesn't matter, most people will quickly lose both Allen wrenches.
The minimum rope size specified for the Macrograb means that it will only be of interest to the "bigger is better" crowd. They are welcome to it.
[ Top | Micrograb B53 | Micrograb B53A | Return to Rope Grabs ]
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I acquired my Petzl Macrograb B52, Version B in 2017 as part of Bob Thrun’s collection.
My Petzl Macrograb B52, Version B is 114 mm. long, 90 mm. wide, 53 mm. high, and weighs 340 g.
Version B has an 8 mm. hole drilled throug the shell, directly in the rope path above the cam.
Version B has the same markings as Version A, except the rear
of the frame is stamped with "03093K" instead of "001966"
I do nt know what the extra hole in the shell is for, and the instructions don't give an explanation.
This Macrograb came with three Allen wrenches and three replacement keeper cables.
[ Top | Macrograb B52 Version A | Micrograb B53A | Return to Rope Grabs ]
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| Front View | Rear View | Side View |
I acquired my Micrograb from On Rope 1 in September 2000. I acquired another in 2017 as part of Bob Thrun’s collection.
The Micrograb is a smaller version of the Macrograb. The frame is milled from aluminum. The rectangular-shaped rope channel is 15.7 mm. wide. The inside of the shell has a milled depression that the cam forces the rope into. This spreads the load on the rope, and may increase the holding power of the ascender. It is claimed to help reduce rope damage under shock loading, but I can't confirm this. Rock Exotica pioneered this feature, and Petzl acquired it from them.
The cam has 8 rounded teeth, and is held in place by a cable keeper that doubles as a spring that applies a moderate closing force to the cam. The keeper is attached to the cam by a small set screw. The cam axle is an 8 mm. Allen-head cap screw secured with a lock nut. The top of the rope channel is rounded off so that the rope does not bend over any sharp corners. In addition to the axle hole, the frame has two small holes. One is for the keeper, and a second, drilled from the side, accepts an Allen screw to hold the keeper in place.
The front of the frame is stamped with an arrow pointing up,
"EN567," "9≤Ø≤13mm,
"3/8"≤Ø≤1/2," "
"CE 0197," an icon showing how to rig the cam,the Petzl
logo, and Petzl’s "reading
is dangerous" icon. The rear of the frame is stamped
with "00175L" which I assume is a serial number or date
code.
The Micrograb is another clunky-looking device. Its a shame that Petzl couldn't round the inside of the rope channel, after all, most of us use round ropes instead of square ones. The cap screw axle is a cheap way to mount the cam, and it makes it excessively difficult to put the Macrograb on rope or take it off. Petzl supplied a 5 mm. Allen wrench for the cap screw but forgot to provide a wrench for the nut. Things are even more hilarious than on the Macrograb: the cam set screw requires a 2 mm. Allen wrench while the frame set screw requires a 1.5 mm. wrench. In all, three wrenches are provided to be lost at the first opportunity.
I suggest that anyone seriously considering the Petzl Micrograb look at the PMI Grip-Tech Jr. before committing themselves.
[ Top | Macrograb B52 Version A | Micrograb B53 | Return to Rope Grabs ]
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I acquired my Petzl Micrograb B53A from On Rope 1 in 2016.
My Petzl Micrograb B53A is 76 mm. long, 81 mm. wide, 34 mm. high, and weighs 144 g.
The frame is milled from aluminum. The rectangular-shaped rope channel is 15.3 mm. wide. The inside of the shell has a milled depression that the cam forces the rope into. This spreads the load on the rope, and may increase the holding power of the Micrograb. The top of the rope channel is rounded off so that the rope does not bend over any sharp corners.
The cam has 7 rounded teeth. The cam axle is 7.5 mm. in diameter and held in place by two set screws. A captive spring pushed the cam to the closed position.
One side is [printed with "Pat. Pend.," "EN567:2013," "10≤Ø≤13mm," "16B0009514307," "CE0082," a scanner conde, and "EA[." The other side has a printed Petzl logo and is stamped with an up-pointing arrow with "UP" inside, book-with-an-"i" icon, and "MICROGRAB." The spine is printed with the UL "CLASSIFIED" logo, "MEETS NFPA," "1983 (2012 ED.)," "T MBS 5kN, and "10≤Ø≤13mm."
The Micrograb B53A has bettter lines than the B53, but I am still not impressed. I like the thumb tab, but that is about it.
Although Petzl supplies an Allen wrench, I would think that they could find a better way to open the B53A for rigging than relying on such a tiny tool.
I still haven't found a square rope to fit the square channel.
Enough said, this isn't something that I would put up with for what I do.
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