Answers
The sits was 18 foot deep 48 ft by 60 ft.? that the contractor had done an OSHA slope on the sides. The sides would not stand. The project stood still for 2 months. In the picture we put in a foot of rock. This was for tanks to allow gravety to drain from the plant
I came in to do the shoring. I drilled and cement steel beams and placed wood lagging.
The excavator is medium stick. I don't think it would matters that much the size of boom & stick. The guy that sold this told me told me it was 20 ft. I was not happy to find out that it was 18 ft. and I think a 20 ft. would work just as well. But then this was close to what I needed foe the long reach work. This operates as 3rd member. We use 3rd members on other applications but to dig is another story, that is why a pattern changer make it part of you.
Pattern changer would do the following.
Boom hoist stays the same.
Crowd control changes to operate bucket cylinder on origional stick.
Bucket control changes to operate bucket on add-a-stick.
Aux circut control changes to operate crowd cylinder on origional stick.
This is because I don't want to change the hydraulic lines to accomplish what a flick of a switch will do.
You could take the crowd cylinder complety off and put a piece of steel in place of the cylinder, which is a lot of work.
I can pull into a site and be up and running in a very short time.
I hope this answers your questions.
I also have a 5 ft. extention for the stick on a Komatsu 150 that dig 25 ft. deep in confined areas and 35 ft of reach.
http://www.darrylmueller.com/komext.jpeg
I answers all the questions