Camlock stud cutout radii? (was - is there a correct way?)

[Timleech]

Tim,
I have done a fair bit of work on D1-3 studs and have full engineering drawings.
I have found out that a lot of what's there isn't needed.
Those side radii are not always needed and it depends on the type of cam fitted.




If the side radii are omitted and the sides flatted off they fit and work fine.
What is critical is the diameter of the main cutout and it's position.

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John (or anyone)

I've just made 18 threaded blanks for D1-8 metric studs, just (!) have to cut the radius and locking groove now, still working out how I'll go about it. The sample I'm working from has a main cutout of apparently 1.125" diameter, but this is 'feathered off' towards the free end of the pin. Is this common/essential/unnecessary? I haven't seen any D1-8 pins with that side radius shown in your drawing, but some of my D1-3 have it

Thanks
Tim

[Black_Moons]

Iv seen a sorta side radius on my pins, but that was due to giant maring when the chuck came partialy loose during a parting operation..

Hate to hijack, but what is the radius 'stud cuttout radii' for D1-4 or a D1-X pin chart to awnser both the OP's and my question?

[John Stevenson]

Get a lump of square or hex, belt a thread in it to match the studs, bung it in the mill vise with the new pin sticking out. Lob a 1 1/4" end mill or shell mill in the spindle and with it positioned with the DRO [ use an existing stud as a position setup ]

Support the sticky out end on a packed up vee block and clamp it down so it can't unscrew. plunge feed the cutter.

You may need to do a couple of passes with a 1 1/4" cutter.

Swap to another pin and do that.

[Timleech]

Get a lump of square or hex, belt a thread in it to match the studs, bung it in the mill vise with the new pin sticking out. Lob a 1 1/4" end mill or shell mill in the spindle and with it positioned with the DRO [ use an existing stud as a position setup ]

Support the sticky out end on a packed up vee block and clamp it down so it can't unscrew. plunge feed the cutter.

You may need to do a couple of passes with a 1 1/4" cutter.

Swap to another pin and do that.

I'd got something along those lines in my head, I've centre drilled the outer end of the pins specifically so that supporting them with dividing head tailstock is an option - could even have the threaded support in the DH chuck, but I'm thinking of trying to arrange cutting the locking groove in the same setup.
Doesn't answer my question though - is a purely circular cutout OK, the ones I'm working from have it opened out a bit at the free end? I'll have to check with some others.

Tim

[John Stevenson]

Tim,
Only worked on D1-3's and these were circular, even bought a set from J&L in the first place but found that they were available in UNF and metric and I wanted BSF,....... typical, hence making some.

I took the drawings from a brand new set and on the D1-3 a slug of 0.750" steel was a perfect fit.

Could the 'taper' be wear ? Because it's the free end that takes the grunt.

[Timleech]

Tim,
Only worked on D1-3's and these were circular, even bought a set from J&L in the first place but found that they were available in UNF and metric and I wanted BSF,....... typical, hence making some.

I took the drawings from a brand new set and on the D1-3 a slug of 0.750" steel was a perfect fit.

Could the 'taper' be wear ? Because it's the free end that takes the grunt.

No it's not wear, it starts roughly at the (visibly abraded) contact point with the cam and continues to the end of the cutout. Those are on a catchplate, I'll take some off a chuck to compare.

Thanks
Tim

[Timleech]

I've checked some brand new D1-11 (P-BI brand) pins tonight, they show the same 'fairing off' at the free end of the cutout. Thinking very roughly about the geometry, in my head, I wonder if it makes the locking more secure as the cam is bearing on a slightly reduced 'angle'?
I'll make them initially with the purely circular section cutout and see how well they work.

Tim

[John Stevenson]

Tim,
Those pins I gave you that are for a smaller fixing, are they tapered as well ?

I only have about 6 or 7 sets of D1-3 here, nothing else on camlocks so i can't check.

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[Timleech]

Tim,
Those pins I gave you that are for a smaller fixing, are they tapered as well ?

I only have about 6 or 7 sets of D1-3 here, nothing else on camlocks so i can't check.

.

I'll have a look tomorrow. It's dark & wet out there at the moment !

Tim

[John Stevenson]

What about being haunted ?

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