I have a Cat 299D2 XHP, which at the outer edge of the tracks measures 77 inches. I'm finding buckets at 72" and 84". This machine will be used to scarify some glacial hardpan till with a ripper, then the bucket to dig up the hard earth and move it. I can't decide whether I should get the narrower one for strength, or the wider one for capacity, given that the digging will be fairly hard.
I would want to be wider than the tracks so 84 with teeth for tough going
You can get 78" buckets. Look at Virnig or Bradco buckets. Bigger capacity and better built than OEM CAT buckets. I would agree that 84" is better especially for a tracked machine. Since you are ripping it first, you likely would not see an impact on the ability of the machine to dig with the larger bucket. I have an 84" Bradco with a tooth bar on it, that works great if you need to dig and break the material out, the key here is to get a bucket without the extended lip, since the tooth bar extends beyond the lip of the bucket by about 6" and CAT's bucket breakout performance is not very high. You lose some capacity with that bucket verse the extended lip version, but it works better with the tooth bar.
Wow, better built than Cat. Without the lip. Would I necessarily need a ripper with a tooth bar? This is very hard stuff... been under a mile-high glacier during the Ice Age.
Everything we deal with is glacial moraine. I know the material well. There are several styles of buckets, there is an extended lip which means the distance from the front edge of the bucket to the back is longer, great for grading, leading edge of bucket is easy to see. The regular bucket is shorter from leading edge to the back of the bucket. This reduces capacity but just like an excavator bucket the shorter the distance the greater the breakout force. The tooth bar bolts to the front of the bucket and fits over the cutting edge, it increases the regular bucket to essentially an extended lip version. If you bolt the tooth bar to an already extended lip bucket you will have trouble breaking the bucket out of virgin material, especially with a CAT. That is why starting with a regular lip bucket is important if you are going to put a tooth bar on it.
Glacial till up here is more on the lines of working with conglomerate and is very high in silica. It was marginal to rip with a Komatsu 375 or D10 Cat and a single shank ripper. If you are going to work with it expect high wear rates and lots of broken stuff.
The top pic is the extended lip version. It is 38" from leading edge to back of bucket, the bottom is a regular grading bucket with the tooth bar. It measures 32" from front to back, about 38" from tips of teeth to back of bucket. The tooth bucket is a Bradco and the extended lip is Virnig.
Gee, Bradco and Virnig are pretty proud of their buckets, aren't they? ($2,100) I also need a scarifier, but the only two options I've found sure don't seem very strong. https://clfab.com/products/xr-ripper/ https://bobcatbucket.com/product-catalog/bucket-attachments/ripper-scarifier-attachment/ I did find a good tough one, but it's in Australia!
I was able to get two Virnig buckets last year for around 1600 delivered a piece. A 78" and an 84". Did you talk to someone from Virnig? The Virnig buckets can be had with curved steel on the inside of the bucket, but the back of the bucket is a 90 degree back. It prevents the material form sticking as easy on the inside, but you can use the back of the bucket to backdrag. Very cool feature, which is the reason I like their buckets so much.
I have a Bobcat Scarifier that I have had for years. Has 6 tines on it. Works well, pretty simple. Not sure if they still make them or not.