Boring Head repair?

Dynahoe Dave

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I got chance to get a Criterion DBL-202 - but the gib is cracked from the main piece.

How does this effect operation? Make it not usable?

I am only guessing, but it looks like this kind of break might make adjusting annoying. But if I added a coulpe of roll pins, or solid pins to keep it from falling out / loose, could that work?

I can't imagine that the thin web really did much as far as carrying the load of the boring bar against the work.

I read some boring head threads, and I know the outer 2 gib screws are for adjusting the sliding, and the center one is for locking the slide once it is set.

From what I saw in other threads, it seemed like the DBL-202 is better than the el cheapo import ones, which I want to avoid. The really nice ones, obviously are BIG $, and I am not running a business..

I have a J-head 1HP Bridgeport mill.
 

JimDawson

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1 or 2 pins should work. And yes those are nice boring heads.
 

mikey

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Dave, did you already buy it? If not, I would pass on this head. The gib is important and it needs to work properly if the lower/sliding part of the head is to work as it should. If the gib is loose, even if you guide it on pins, it may not stabilize the lower part of the tool solidly. I'm guessing at that but personally, I would want an intact gib.
 

Dynahoe Dave

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I got it cheap, about what the el cheapo import ones go for. I'll figure out a way to fix it. It will be easier to evaluate once it is in hand.
 

tcweb

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Can you post some pictures of your repair? I picked one up - similar situation.

Also, one of the expansion plugs (dorman 550-004) is missing. Recommend buying a new one, or turn a replacement on the lathe?

-Tom
 

Dynahoe Dave

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Once I got it in hand, I looked at it. Checked how it moved, and how the set screws were set. Decided to try making some holes. It worked fine as is, so I have not gone after adding the pins yet. I did only make holes out to 1.25" diameter, not sure if bigger might show up some other problem.

I tried to find information on what a 550-004 is, but got almost nowhere. One site has a PDF catalog thatmight show it, but I have to sign up for a free trial before I can view the full thing, so that's not happening. Looking at the head, I can see only one place one might have been, covering the fine threads of the diameter adjusting screw from the side opposite the scale. It makes sense that that should be covered, but mine is missing one also.
 
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