Sizing a hammer/breaker to your mini

[mrdenial]

I've been looking at replacing my 2001 cat 302.5 with someone stronger and with a cab. I want something that can handle a decent hammer in case I run into some rock...which we have a ton of here in bend.

I've tested an HR16 by Terex, seemed like a nice machine.
It's a 7700lb machine with a bucket force of 8000lbs and a stick force of 3600lbs. One thing I noticed is that the cylinder for the main stick is on top instead of below. The sales person that it's to prevent damage.

I'm also interested in 2005 model or older Cat 304cr. From what I've heard they are nice machines. ~9500 lbs versus the new ones at about 10,500.

As far as a hammer goes, the local Terex dealer is putting a atlas copco PB 310 on their HR16. They say that the PB 310 is rated for a 11k to 19k machine, but th HR16 handles it just fine.

Cat says that they will only rent you a 500 ft lb breaker for the 304 or 305. It seems like if the HR16 can handle a PB 310 which is a 750 ft lb breaker, the 304 or 305 should be able to handle a PB 420 (1000 ft lb). The older 304s have about 19 gpm on the aux. and the PB 420 need 16-24. I'm guessing cat doesn't want the liability of letting you rent a hammer that's rated for a bigger machine.

Does anyone have any experience sizing a hammer to their mini?

Thanks,
Daniel

[Nac]

It all has to do with the GPM and the weight of the hammer some hammers are heavy and when you boom all the way out the machine gets tippy. I run an Atlas Copco hammer it rated for 900 lb class on my Komatsu PC-45

[mrdenial]

What year is your komatsu? Sounds like it's about a 10k machine. Do you have any problems with your unit tipping? Is it a zero tail swing?

Do you know if your hammer the 420?

It sounds like if the GPM is right and the machine handle it without tipping you are okay. The other thing I was wondering was if putting a large hammer on the machine would beat the crap out of it. I was told that the atlas copco was a little easier on the machines and they were less noisy.

Thanks for the response.

[Ford LT-9000]

You really want to put a breaker on your machine you will rattle the machine apart busting the rock in the Pacific Northwest area. Rock breakers are more for concrete and asphalt.

If you really want a breaker find a realitivly cheap used machine just for rock breaking purposes. So the hammer pretty much never leaves the machine.

As for breaker seeing as your in Oregon look into a Stanley or Rock Ram breakers the Stanley breakers are not too bad. Like I said they beat the crap out of your machine people that say they don't doesn't know what hard rock is.

[Nac]

It is a 2003 Komatsu PC-45 it about 11,000 lbs i have no problems with it being tippy. But Ford LT-9000 is right it is best suited for concrete or asphalt or shot rock.

[Ford LT-9000]

If you do get jobs where you have rocks that can't be dug or moved you should find a good small blasting contractor. Sure it adds to the project but your not beating the crap out of your machine. If your doing demo like Nac does a breaker works good.

[mrdenial]

Thanks for the input. I was thinking of using the hammer when I ran into rock digging the utility trenches or if I'm doing a digout for a foundation and needed to take off 6 inches or so of rock in a confined area. All of our rock is lava rock which can break easy...or hard depending on the composition. Basically, I was thinking of putting about 40 hours max/year on the machine using a hammer.

-Daniel

[Bob Horrell]

If you are only going to use it 40 hrs a year, I would rent. I always rent a machine and a hammer when needed. That way I don't beat up my equipment. Hammers are hard on your pins no matter how well you grease them.

[TES]

Cat 305CR,Cat H63 Aux Hyd Hammer, QCoupler, Hyd Thumb, 18" and 30" buckets.Amazing machine with a perfect sized hammer for blasting up small boulders, masonry work, demo's etc. Thumb is perfect for setting stones for boulder retaining walls.Email me for more info?

[mrdenial]

That seems like a nice machine. I ended up purchasing a 304CR as it's a bit lighter. I've heard people say that the 305 is a much better machine, but it's also close to 10k more...

[TES]

Both and the 305CR has a bit more oomph! when diggin in deeper harder soil. I needed a little more weight to handle the H63 and this does the job for me. Perfect for small foundations (mostly residential) and with the added hydraulic thumb the little beast has no problem ripping apart small 1-2 story ranch style homes. For anthing taller than 1.5 stories i wouldnt reccomend either. Anyway tell me about your 304? any attachments? what type of digging do you do?