Bulldog OAR ascender/descender

[surveyor]

Thanks, The rack is made from standard steel roller links (ANSI rated at over 14,000 lbs breaking strength). basically I used half the rollers as the standard roller chain, in order to make room for the rope to pass through the device. Each master link has a side plate with a spring steel clip which engages with slots in each pin, which allows the bottom link to be attached to the top hole in the hitch climber pulley. The headstock is my own design.

 

Personally, I think the OAR is superior because it has almost zero sit back, and is mid-line useable, and the very durable steel links are easily replaceable.

[surveyor]

I continue to work on the OAR, and believe I have made an improvement, both to the way it fairleads, the smoothness of release, the grip on rope, and it is slightly lighter then my other three arm OAR. The video shows a working mule, I plan to add a beefier spine once I receive a material order. I do not show in the video, but I have machined a groove on the inner part of the arms in order to ease the passage of fatter ropes through the device. It likes my Yale half inch rope, and works also with my weight on Imori, tachyon, rocketline, and KMIII, it creeps only on velocity. because of the cantilever bottom arm, the grip there is more proportional to the climbers weight, as it will release for my young son with his light weight also. This OAR also will self tend with KMIII and Rocket line when there is little or no weight on the hitch attach point. I hope to receive feedback from a gathering of arborists who I am sending a demo unit to in Florida this coming week.

 

 

 

 

[Old Mill Tree Care]

I absolutely love the look of this.

The only question I have is how long do the friction parts last and how easy is it to change them?

I know I depends how often on climbs.

 

I used a Lockjack for years and changing the clutch is cheap and simple. Will the OAR be similar?

 

 

Sent with my iPhone from me, to you!

[BenR]

Hi Old mill,

 

I trialled an OAR for a while. The wear parts are replaced really easily. They are essentially motorcycle chain links. Good device that has great potential.

[Old Mill Tree Care]

Hi Old mill,

 

I trialled an OAR for a while. The wear parts are replaced really easily. They are essentially motorcycle chain links. Good device that has great potential.

 

Would you buy one though or stick with what you've got?

 

 

Sent with my iPhone from me, to you!

[BenR]

I think it is a great piece of kit, but it was a bit of a fiddle getting it to run perfectly on different rope. However, Gordon seems to have improved it quite a lot since the version I tried. For the moment I am sticking with what I have. I almost went for a rope runner too but I short on cash and want to see how it develops. These days I'm not so keen to try stuff until it is up to mass production standards. The first wrench was great and then kevin improved it. Kind of waiting for the same to happen with the OAR and the rope runner. Just ordered a drum for my unicender though

[kennyjames]

Where to buy it ? What is price ?

[surveyor]

The Bulldog OAR is still a work in progress. As I receive feedback I try to make improvements. It is likely that it would be improved by spring-loading the bottom arm, so that it "sticks" as it transitions from ascending to descending, especially on a narrower rope. Being biased about the OAR I am awaiting further feedback from some seasoned arborists.

[surveyor]

I have made a functional improvement to the Bulldog OAR by adding a spring to the lower arm. Thanks to my son for helping with the video, and for all who have commented on the Bulldog OAR.

[BenR]

Looks awesome mate. Much improved on the version I tried a few years ago. How is the self tending with the spring added in?