Criterion Boring Head Models?

[rwm]

I am looking at Criterion boring heads. I see two different 202 models. On the silver part, one is labeled DBL 202 and the other is labeled 202B. What are the differences? Is one an older model? Which one do I want?





Also- how can I tell if the shank is removable or integral? Can you tell by looking?

 

[Ulma Doctor]

I am looking at Criterion boring heads. I see two different 202 models. On the silver part, one is labeled DBL 202 and the other is labeled 202B. What are the differences? Is one an older model? Which one do I want?





Also- how can I tell if the shank is removable or integral? Can you tell by looking?

Hi Robert,
sorry, i don't know the difference between the 202 & the 202B
but the integral shaft is pictured in PIC1

in the picture below you'll see the shank's parting line

 

[mksj]

No difference for R8 arbor mounting, the flat top is a CNC style (CB-202, CB-203, etc.) which the head can mount to a larger flat surface on other types of holders or extensions (head to shank adapters). I have the CB-202, works well, and a Narex VHU-36 for anything larger/facing.

 

[rwm]

I remain confused. In pic #1 that I posted the shank indicates a 7/8-20 thread, so I do not think it is integral?
Same item:


I still don't know the difference between the DBL202 and the 202B. They look to be the same. I cannot find this in Criterion's literature.

 

[jwmelvin]

I have a DBL-202A, which takes 3/8” boring bars. Maybe the -202B is the version that takes 1/2” bars?

I imagine [mention]mikey [/mention] would know.

 

[mikey]

I remain confused. In pic #1 that I posted the shank indicates a 7/8-20 thread, so I do not think it is integral?

I still don't know the difference between the DBL202 and the 202B. They look to be the same. I cannot find this in Criterion's literature.

All the 2" heads in the DBL-series have 7/8-20 threads. As pointed out by Mark, this allow these heads to fit many different tool holders.

There is no difference between a DBL-202 and DBL-202b. I can't recall when they stopped using the designators on the tool holder part of the head but the "b" means the head takes a 1/2" dia. boring bar in all three bar holder holes. The model "a", or DBL-202a, takes 3/8" bars in the center and outer bottom holes and a 1/2" bar in the horizontal hole. Boring range and all other features are the same between the "a" and "b" models.

 

[rwm]

Do they make an integral shank that cannot be removed or are they all removable? I have heard both stories.

Also- Any reason I would not want the 203 model? I will need to buy boring bars anyway so I could buy 1/2 or 3/4". My mill is a PM 727v so the 3" head is probably overkill but is there a downside if I get one at a good price?

 

[davidpbest]

I have the 202 and 203 and also a Wohlhaupter UPA 3 (see below). I have used these on an RF-45 as well as my PM-935. The 203 is definitely a beast for a mill like the 727, but it all comes down to the diameter requirements. A Wohlhaupter or Narex might be a better choice than buying 2 Criterion heads. Just a thought. I found my Wohlhaupter on eBay and it was obviously used but in terrific shape. You might want to check out this one on eBay (has R8 shank, but it just the head and doesn't have all the accessories which I've never used). More info on this type of head here.

 

[rwm]

That Wohlhaupter is beautiful. What size boring bar does it take? I suspect it will bid up high!

 

[davidpbest]

That Wohlhaupter is beautiful. What size boring bar does it take? I suspect it will bid up high!

Ask the seller to measure the boring bar receiver hole diameter. It could be metric (12mm) or imperial (1/2"). The one on eBay is smaller than the one I have. The kit I have is imperial, takes 3/4" tooling, but comes with collets that shim that down to either 1/2 or 3/8".