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Clog Expedition

Version A Version B Version C
Version A Version B Version C
 
Version D Version E Version F
Version D Version E Version F
 
Version G Version H Version I
Version G Version H Version I

Overview


I have seen photos of two earlier Clog handled ascenders with frames like my Version A and cams like those on my handleless Clog ascenders Versions A through E. I would like to get a pair of each for my collection. If you have ones that you can part with, please email me.

Version A
(#2159)

Front Rear
Front Rear

Technical Details

I acquired this ascender in 2017 as part of Bob Thrun's collection.

Version A is 195 mm. tall, 109 mm. wide, 25 mm. thick, and weighs 238 g.

The ascender shell is a roughly "D" shaped piece of unfinished 4.2 mm. thick aluminum bent to form a rope groove on one side and to hold the cam pivot and safety on the other. The handle opening is fairly large, and a molded rubber hand grip is glued to the shell. A 15.3 mm. hole at the base of the shell serves as a rope attachment point. A second 15.3 mm. hole provides a means to attach non-load-bearing slings to the shell above the cam. The rope channel is 15 mm. wide.

The cam is a skeletonized steel casting with a (4.5)^4(4.3)^4 conical tooth count. The teeth are well made compared to those of some other toothed ascenders. The cam radius increases from 43 to 57 mm. over an angle of 41°, giving a 22° cam angle. The inner cam face radius reduces from top to bottom to accommodate various sized ropes. The cam and cam spring are mounted on a solid 7 mm. steel pin. The pin is expanded at both ends to keep it in place. The cam safety is a crudely machined aluminum lever mounted on a 3 mm. roll pin in the same shell channel as the cam. A second spring serves as a safety spring. Normally this spring holds the safety where it blocks the cam from opening. When the end of the safety lever is depressed, the opposite end pivots upwards so that the cam is no longer obstructed.

There are no markings on the shell of this ascender. "CLOG" is cast on top of the cam.

Comments

The only significant difference between Version A and Version B is that Version A does not have "CLOG WALES" inside an ellipse stamped on the shell.


Version B
(#24, 2158)

Front Rear
Front Rear

Technical Details

I acquired this pair from Mountaineering Outfitters in Driggs Idaho in August, 1980, but the ascender is at least five years older than that, since Version D was available in 1976. I acquired another left-handed ascender in 2017 as part of Bob Thrun's collection.

Version B is 195 mm. tall, 109 mm. wide, 25 mm. thick, and weighs 237 g.

The ascender shell is a roughly "D" shaped piece of unfinished 4.2 mm. thick aluminum bent to form a rope groove on one side and to hold the cam pivot and safety on the other. The handle opening is fairly large, and a molded rubber hand grip is glued to the shell. A 15.3 mm. hole at the base of the shell serves as a rope attachment point. A second 15.3 mm. hole provides a means to attach non-load-bearing slings to the shell above the cam. The rope channel is 15 mm. wide.

The cam is a skeletonized steel casting with a (4.5)^4(4.3)^4 conical tooth count. The teeth are well made compared to those of some other toothed ascenders. The cam radius increases from 43 to 57 mm. over an angle of 41°, giving a 22° cam angle. The inner cam face radius reduces from top to bottom to accommodate various sized ropes. The cam and cam spring are mounted on a solid 7 mm. steel pin. The pin is expanded at both ends to keep it in place. The cam safety is a crudely machined aluminum lever mounted on a 3 mm. roll pin in the same shell channel as the cam. A second spring serves as a safety spring. Normally this spring holds the safety where it blocks the cam from opening. When the end of the safety lever is depressed, the opposite end pivots upwards so that the cam is no longer obstructed.

The words "CLOG WALES" inside an ellipse are stamped on the inner shell surface, and "CLOG" is cast on top of the cam.

Comments

This ascender combines a very well made cam with a poorly executed shell and safety. The cam is identical to the cam on the handleless Clog Versions E, F & G. There are no sharp edges on the ascender in either the rope channel or the sling attachment holes, but the cam pin does have a sharp lip. I don't like the way the cam pin is expanded, I would prefer to see round head rivets used here.

Clog ascenders are quite large. This makes them popular among snow and ice climbers, who must wear heavy mittens while climbing fixed ropes. Of course, the large size is a disadvantage for caving. The ascender is easily opened with one hand, but only the wrong hand. It is very difficult to open the right-hand ascender with one's right hand without going through some severe contortions. The ascender can be removed from the rope by simply depressing the safety with one's thumb and lifting up on the handle. It is much more difficult to put the ascender on the rope with one hand, particularly the proper hand. Normally it becomes a two-handed operation.

The rubber hand grip is very comfortable, but is excessively heavy. The hand grip provides some insulation in winter conditions, but there is a rib of the aluminum shell exposed next to one's palm so the protection is not complete. In many climbing systems (e.g., the lower ascender in the Mitchell System) ascenders are pulled up the rope from above. Clog ascenders are not as easy to grasp from above as some others (such as the Jumar).

The ascender is attached to the harness by a carabiner through the bottom attachment hole. Clog eliminated carabiner attachment holes from later expedition ascenders because of two cases of carabiner failure (see D. Moorhouse, Clog Climbing Gear, Off Belay #30, Dec. 76, pp. 54-55). These were caused by sideways gate loading on carabiners lodged incorrectly in the attachment hole. This could happen also occur with Petzl's, S.R.T.'s, handled C.M.I.'s, etc. I caution against using carabiners for attaching slings to ascenders.

Clog ascenders also have a disadvantage shared by all handled ascenders using a sheet metal shell. When crossing a sharp lip, it is very easy to carelessly place the ascender so that the cam grips the rope just above the lip, while the base of the handle sticks out over the pit lip. When weight is transferred to the ascender sling, the shell tends to bend 90°. This effectively destroys the ascender. Milled or cast frame ascenders, such as the C.M.I., Jumar, and S.R.T. are more likely to survive this mistake.


Version C
(#2156)

Front Rear
Front Rear

Technical Details

I acquired this ascender in 2017 as part of Bob Thrun's collection.

Version C is 195 mm. tall, 111 mm. wide, 24 mm. thick, and weighs 222 g.

The ascender is very similar to Version B, so only the differences will be noted. The hand grip is plastic molded onto the shell. A small extension on the base of the plastic hand grip protects the inside bottom of the handle opening so that slings can be tied directly through the handle.The lower attachment hole was eliminated due to the safety concerns mentioned above. The shell is blue anodized.

The words "CLOG WALES" inside an ellipse are stamped on the inner shell surface."CLOG-WALES" is molded into both sides of the plastic hand grip. "CLOG" is cast on top of the cam.

Comments

All of these changes are improvements, except one. Clog eliminated carabiner attachment holes because of two cases of carabiner failure (see D. Moorhouse, Clog Climbing Gear, Off Belay #30, Dec. 76, pp. 54-55). These were caused by sideways gate loading on carabiners lodged incorrectly in the attachment hole, but without the hole there is no easy way to prevent ascender rotation on horizontal or sloping ropes. The resulting design is something of a nuisance, since slings must now be tied through the handle. Unfortunately, the slings pull towards the outside of the ascender, i.e., away from the rope and towards the hand. This causes the ascender to pivot slightly when loaded, leading to lost efficiency

The hand grip is less comfortable than the rubber one of Version B, but is superior in terms of weight and durability. It also completely surrounds the aluminum shell, providing better cold weather protection.

I still wish the cam pivot had been changed, since I really don't trust that style rivet.


Version D
(#25, 2157)

Front Rear
Front Rear

Technical Details

I acquired this pair of ascenders from Avalanche in Pittsburgh, Pa. in April, 1978. At the time it was the current production model. I acquired two more pair in 2017 as part of Bob Thrun's collection.

Version D is 195 mm. tall, 107 mm. wide, 25 mm. thick, and weighs 230 g. The rope channel is 14 mm. wide. The cam radius increases from 43 to 57 mm. over an angle of 41°, giving a 22° cam angle. The tooth pattern is (4.5)^4(4.3)^4.

The ascender is very similar to Version C. The cam safety is a more elegantly shaped steel casting, and is mounted with a steel round head rivet. It functions in the same manner as the safety for Version C.

"CLOG-WALES" is molded into both sides of the plastic hand grip, and "CLOG" is cast on top of the cam. The shell markings present on Version C were eliminated.

Comments

The new cam safety looks mich better, but the improvement is mainly cosmetic.


Version E
(#1505R, 1567)

Front Rear
Front Rear

Technical Details

I acquired a right-handed Clog Expedition, Version E ascenders from Richard Biggs in 2009, and a pair from Mike Ford in 2012.

Version E is 196 mm. tall, 105 mm. wide, 28 mm. thick, and weighs 243 g. The rope channel is 16 mm. wide. The cam radius increases from 43 to 57 mm. over an angle of 41°, giving a 22° cam angle. The tooth pattern is (4.5)^4(4.3)^4. The cam pivot is a semi-tubular rivet.

"CLOG-WALES" is molded into both sides of the plastic hand grips, and "CLOG" is cast on top of the cam. The first right-handed ascender frame is stamped "T1185." The second is stamped with three illegible digits ("552"??) and "784C." The left-handed ascender is stamped "SECOND" in two places, "4 84," and "TES ED."

Comments

The date stamp indicates that these were made in 1984 and 1985. Version E differs from Version D by having a different shape to the cam safety. The safety on earlier versions has flat sides, while the safety on Version E has a raised nubbin on the end near the cam. This raised nubbin pushes against the outer lip of the cam channel, centering the safety in the channel. The Version E safety is also anodized.

The left-handed ascender is interesting because it was a factory second with cosmetic blemishes. Since I acquired this one used, I cannot tell what the original blemish was. Mike wrote, "These are date stamped 1984 and are cosmetic seconds due to what was considered poor black spray paint job but I think they are A1."


Version F
(#1505L)

Front Rear
Front Rear

Technical Details

I acquired my Clog Expedition, Version F ascender from Richard Biggs in 2009.

Version F is 196 mm. tall, 105 mm. wide, 28 mm. thick, and weighs 243 g. The rope channel is 16 mm. wide. The cam radius increases from 43 to 57 mm. over an angle of 41°, giving a 22° cam angle. The tooth pattern is (4.5)^4(4.3)^4. The cam pivot is a semi-tubular rivet.

"CLOG-WALES" is molded into both sides of the plastic hand grips, and "CLOG" is cast on top of the cam. The ascender frame is stamped "T586."

Comments

The date stamp indicates that this ascender was made in 1986.

The orange color on the cam is surface rust - these cam is not plated.


Version G
(#171, 1555)

Front Rear
Front Rear

Technical Details

I acquired a left Clog Expedition, Version F ascender from Terry Wilkins in 2004, a complete pair from from Lawrence Rowles in 2011, and another pair from Steve Swanchak in 2015.

Version G is 195 mm. tall, 105 mm. wide, 28 mm. thick, and weighs 237 g. The rope channel is 16 mm. wide. The cam radius increases from 43 to 58 mm. over an angle of 41°, giving a 23° cam angle. The tooth pattern is (4.5)^4(4.3)^4.

"CLOG-WALES" is molded into both sides of the plastic hand grips, and "CLOG" is cast on top of the cam. Each frame is stamped with the letter "C."

Comments

Version G differs from Version F by having a countersunk rivet rather than a semi-tubular rivet for the cam axle. Neither cam safety is anodized. The Version G pair that I acquired from Lawrence Rowles is anodized purple, the others are black.


Version H
(#218, 2166)

Front Rear
Front Rear

Technical Details

I acquired this pair used from Anthony Morton in 2007, but it is clearly a much older design. I acquired another right-hand ascender in 2017 as part of Bob Thrun's collection.

Version H is 195 mm. tall, 104 mm. wide, 25 mm. thick, and weighs 228 g. The rope channel is 16 mm. wide. The cam radius increases from 43 to 58 mm. over an angle of 41°, giving a 23° cam angle. The tooth pattern is (4.5)^4(4.3)^4.

"CLOG-WALES" is molded into both sides of the plastic hand grips, and "CLOG" is cast on top of the cam.

Comments

Version H differs from Version G by having a plastic thumb safety catch instead of an aluminum catch. Since the catch is unlikely to break, this change also has little impact on the ascender's functionality.


Version I
(#26, 172, 2167)

Front Rear
Front Rear

Technical Details

I acquired this pair from Exkursion in 1993. I acquired a third (right-hand) ascender used from Terry Wilkins in 2004. I acquired another left-hand ascender in 2017 as part of Bob Thrun's collection.

Version I is 194 mm. tall, 105 mm. wide, 26 mm. thick, and weighs 236 g. The rope channel is 17 mm. wide. The cam radius increases from 43 to 58 mm. over an angle of 41°, giving a 22° cam angle. The tooth pattern is (4.5)^4(4.3)^4.

"CLOG-WALES" is molded into both sides of the plastic hand grips, and "CLOG" is cast on top of the cam.

Comments

Version I adds a pin cam stop to the Version H design. This keeps the cam from sticking when the ascender is off rope, but has no function when the ascender is in use.