Criterion DBL 203

[richz]

Just got this boring head but it was completely disassembled. I believe I have all the correct parts. I searched on line but could not find any parts breakdown. All I have found at Criterion’s site was they said the two outer set screws are factory adjusted. Would anyone have a parts breakdown and know how to correctly adjust the outer set screws. I am assuming that they would be adjusted like a regular gib but I have been wrong before.

 

[MrWhoopee]

Just got this boring head but it was completely disassembled. I believe I have all the correct parts. I searched on line but could not find any parts breakdown. All I have found at Criterion’s site was they said the two outer set screws are factory adjusted. Would anyone have a parts breakdown and know how to correctly adjust the outer set screws. I am assuming that they would be adjusted like a regular gib but I have been wrong before.

Yes, just gib adjusting screws. Snug them up until the movement starts to bind, then back them off a smidge. Every boring head I've ever seen has had someone use them to lock it or otherwise played with them.

 

[devils4ever]

Yes, mine have the two outer holes covered in wax or something to prevent messing with it.

 

[mikey]

Would anyone know how to correctly adjust the outer set screws. I am assuming that they would be adjusted like a regular gib but I have been wrong before.

I am attaching the original document from Criterion that should answer your question.

Note that each of the three gib screws has a ball bearing underneath it. That ball bears directly on the gib; the screw only presses on the bearing.

Note also that the center screw is used to lock the tool holder in position once you adjust it; it is not used to adjust play in the gib. The two outer gib screws are only used to adjust play in the gibs; they are not used to lock the tool holder in place.

Finally, let me say that the instructions from Criterion are a bit vague. Adjust the gib screws after the head is cleaned and lubed properly. When adjusting the outer two gib screws, turn the main leadscrew and tighten one of the gib screws until you take up all play between the ball and gib; it will feel solid. Then back off and just bring the ball back into very light contact and stop. Now do the same with the other outer screw. The tool holder part of the head should now move smoothly but should have zero play or movement inside the body of the head. Adjusted as above, it only takes a light snugging of the center screw to lock the tool holder in place for use.

 

[Eyerelief]

Are there bearing balls under the gib and gib lock screws?

 

[mikey]

Yes, three screws with a ball bearing under each screw.

 

[Eyerelief]

My bad Mikey. I went right to the document without reading your post. You describe the head and the setup process well.

 

[richz]

Thanks for the info guys.