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What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic heavy)

PostPosted: Wed Mar 09, 2016 7:11 pm
by GWiens2001
Needed to mount up a safe lock today, and decided it was time to give pictures of what is inside the lock. It may help to know the terminology. Keep in mind that I am not a safe tech, and anybody should feel free to correct anything I have written in error.

This pictorial is of a Sargent and Greenleaf 6730 safe lock. Some safe locks will be identical, or nearly so, while some others can be very different. However this is a very common lock.

Mounted, it looks like this:

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With the only exception being that they have a change index, which is 8 ½ numbers off. Here is a picture where I used a file to add the index mark at the correct location.

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Here are the parts and the primary tools needed. The parts include the lock body, dial, dial ring, dial ring bushing, spline key and screws. The tools are screwdrivers, a fine point marker and a hacksaw. Also have a display mount.

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To start, take off the back cover of the lock by removing these screws.

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This is the bolt. This is what the lock uses to block the boltwork of the safe door.

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This is the lever.

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Here is the lever already removed in steps below, but showing another angle.

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This is the fence.

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This is the drive cam. This part can be lifted out if the dial spindle is not yet installed.

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The bottom side of the drive cam has a post that engages the fly of the first wheel.

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This is one of the wheels. (More about them later).

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The drive cam has several parts to cover, Some we will deal with later. But here is the area where the nose of the lever drops in. The four grooves are possible locations for the spline key. More on this later.

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Right contact point. You don’t need to know what that means for now, just so you know what the term refers to.

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Left contact point.

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This is the nose of the lever, mentioned above.

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The lever spring, which pushes the lever down towards the center of the wheels.

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The change key hole in the wheel.

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A fly. This is one of three in this lock. This is what allows the lock to be dialed in opposite directions, but still be able to open with the same combo when everything is working correctly. More on them later. But this fly is rotated to the limit in one direction.

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And rotated in the other direction.

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This is where the fence is mounted in the lever.

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This is one end of a pivoting, spring loaded lever called the relocker. The back cover presses down on this end, and lifts the other end out of a hole in the bolt.

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Here is the other end. Since the back cover is off, the relocker is engaging the bolt. Even if the correct combination is dialed, the bolt can not be drawn in.

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Relocker engaged in the bolt…

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And disengaged. Used my finger to act as the back cover on the other end, lifting the relocker out of the hole in the bolt.

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This is the back cover end

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Pressed down

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Here the fence is down inside the gates.

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This is one of the gates. Each wheel in the lock has one, and all must be lined up under the fence for the lock to allow the fence to drop and unlock the bolt. (Remember, the drive cam has already been lifted out).

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When the drive cam is installed, and the drop zone is not under the nose of the lever, the lever is held up like this. If you look at the lock body just above and to the left of the lever in this position, you can see that the lever can not be moved inwards, and since the bolt is attached to the lever, the lock can not be unlocked if the lever can not drop down.

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And when the gates are lined up and the drive cam (still removed in this picture) has the drop zone under the nose, the lever drops down like this, clearing that molded blocker in the lock body.

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Two ways to line up the change key holes with the back cover if you don’t have the combo. One is to use a tool (in this case, the change key is used). Line up the gates, and use the tool to turn it until the nose of the lever stops it.

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Put the back cover on, and look in the change key hole. Lined right up!

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If the change key does not go all the way in, the wheels are not properly aligned. Here am holding the change key up just enough to pretend the deepest wheel is not lined up.

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It should go all the way down, so the flag is entirely below the back cover.

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That would allow the key to be turned. This is the ‘locked’ position of the change key.

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And unlocked.

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The other way is to line up the indexes in the change key holes in the wheels with the screw holding the lock body onto the safe. You can see the index on opposite sides of the change key hole. This is something that it is important to check. When the wheel is locked (Ready for normal usage of the lock), the index should be like this:

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When the wheel is unlocked (ready for the combination to be changed), the index will be aligned parallel to the outer edge of the wheel.

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A somewhat common problem is when one or more of those change indexes are out of phase with the others. Perhaps two are locked and one is unlocked. A symptom of that would be the lock not functioning, and the combination seems to change itself. So be sure to check that all of them are aligned like this before using the lock…

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Waaay in the lock, you can see the torque adjuster. Will cover that later.

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Another visual way of confirming whether the change key hole is turned correctly is to look at the next hole on either side. Here, you can see a thin gap between the brass part inside and the inside edge of the hole. This is locked (ready for use).

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And when there is no gap, the wheel is unlocked (ready for combination to be changed).

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OK, now to remove the lever. Take out the bolt.

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Lift the lever up a little, and you can see that spring better. Do not just keep pulling up the lever, as you do not want to bend the spring.

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Lift it just enough for the fence to clear the wheels, and allow the lever to rotate until the spring is no longer under tension. Yes, it does turn all this way around to achieve that.

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Unhook the lower part of the spring from the bolt and remove the lever.

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This is the hole in the bolt that spring end fits into.

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OK, lever is removed. Here’s what is left.

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Press down the back cover end of the relocker lever.

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With the relocker lever out of the bolt, the bolt can be pulled out. Slowly so you don’t launch the ball bearing.

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The top side of the bolt. The indent on the left edge is where the relocker holds the bolt. The hole is threaded and is where the screw that holds the lever to the bolt fits.

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Flip the bolt over, and you see one additional hole. This is an index hole, and the bearing goes partly in here when the bolt is withdrawn, and in the threaded hole with the screw when the bolt is extended.

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OK, the bearing.

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Remove the bearing, and you can see the spring underneath it.

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Remove the spring.

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Bolt withdrawn position

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Bolt extended position.

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Here you see the relocker lever, spring, and pin that retains it.

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This is the pin that retains it.

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Why don’t I remove it? Because it is staked in place from the outside of the lock body.

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OK, now to remove the wheels, flys, spacers, and so forth.

In the center, at the top of the tube is a retaining clip that is flat spring steel that wraps around.

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Use a hook or pin to pull the top end outwards and upwards.

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Keep moving the hook around, lifting more of the spring up, until it is entirely off the center tube,

Now this is one of the flys.

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It will just lift up.

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This one is different than the other two flys, because it is made to be engaged by the drive cam. The part that rises above the top of the fly is a fair bit taller than the other two flys. Here is a side view.

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No fly!

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Lift off the first wheel.

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If you look at the bottom of the wheel you just took off, you will see a post sticking down. This is the part that will engage the fly of the wheel below this one.

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Now you can see the copper spacer below the first wheel.

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Lift that off, too.

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Next remove the fly from the second wheel.

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Side view of this fly. The fly from the next wheel is the same as this one. You can see that on the top of the fly, the tab does not rise above the top surface.

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Remove the second wheel. (That grease is from the factory. This is a brand new lock that I am taking apart).

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And the next copper spacer

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Third fly

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And third wheel.

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Now remove the brass spacer. Different color, and it goes below the third wheel.

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Now you can see the torque adjuster. By using an allen wrench, you can turn that small gear, which will move the big metal part.

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Look closer, and you can see that the big part has three tabs that are angled down.


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The torque is supposed to be adjusted at the factory, and should require no adjustment according to the manual. So mark the location before removing it.

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Here are the ramps that part moves on. If moved one direction, it applies more lifting force to the wheels, requiring more torque to turn the dial. Turn it the other way, and the part goes down the ramps, reducing lifting force and required torque.

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This is that gear that is turned with an allen wrench.

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Can’t remove it, because it is also staked in place from the outside of the lock body.

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Here are the internal parts, laid out in order.

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The wheels do have differences. The top two are the same, each with a post on the bottom to engage the fly of the next wheel down.

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But the bottom (third) wheel is different. No fly below it, so no post. If it had a post, it would scrape on the parts below.

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Another difference can be seen only if you look very closely. The top two wheels have serrations underneath, along the same circle as the post.

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The bottom wheel does not.

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I don’t know the reason for the serrations, unless it is meant to help hold the fly better. Hopefully one of our real safe techs can explain them for me/us.

OK, that about does it for what is inside the lock! Hope it answers more questions that it creates. ;)

Gordon

Re: What Is Inside an S&G 6730 Safe Lock?

PostPosted: Wed Mar 09, 2016 7:46 pm
by Malekal
yeah.... nope! more questions! More curiosity! Want one!

Re: What Is Inside an S&G 6730 Safe Lock?

PostPosted: Wed Mar 09, 2016 8:50 pm
by GWiens2001
Someone has stated to me that the OP lacks enough pictures, and requested one more. Well, if I must. :roll:

If you look at the above picture, you can see in the cutout section where the brass of the lever and the center spindle of the wheel are locked together. That is when the wheel is locked. When it is unlocked, it looks like this:

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The lock originally used in the post is already packed up for a trip over the pond. So grabbed another lock for the extra pic. That is why the second one does not have a brass inner ring or teeth. Anyway, there you go! :lol:

That was the specific extra picture requested. It was not just a general request for more pics. ;)

Gordon

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Thu Mar 10, 2016 4:18 pm
by MrAnybody
Oh my, oh my. Palms are sweating. This is awesome beyond awesome.

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Thu Mar 10, 2016 8:48 pm
by jharveee
Thanks!
This post, most likely saved my safe lock. Been thinking about taking it apart to see how it works.
I'll just stare at the photos. :D

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Thu Mar 10, 2016 9:19 pm
by GWiens2001
jharveee wrote:Thanks!
This post, most likely saved my safe lock. Been thinking about taking it apart to see how it works.
I'll just stare at the photos. :D


Is this the safe lock you have? If not, what kind do you have? If I have one, I may take it apart and do a photo-shoot for you, jharvee. ;)

Gordon

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Fri Mar 11, 2016 7:53 am
by escher7
Great detail Gord. Supplements many safe books etc. that have fewer specifics.

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Fri Mar 11, 2016 9:11 am
by mdc5150
Great stuff Gordon. This thread seems like it should be a little sticky.

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Fri Mar 11, 2016 9:36 am
by Oldfast
Good stuff here Gordon. Lots of time & thought involved to lay it all out
in a logical and simplistic way. Should be VERY helpful to those starting!

Many of us (myself included) are guilty of trying to get started by cracking our first safe!! lol
As exciting as it is, it's NOT the best way to begin. What you've laid out here is the best start;
understanding the parts that make up a lock and what they are called. Next step would be to
understand how these pieces interact with each other; how does it keep the safe locked, and
how does it allow you to unlock (retract the bolt)? After that, a good deal of time should be
spent with wheel movement; what will the lock allow, and not allow you to do from the dial.

p.s. I was kinda surprised to see such globs of grease in between a couple of those wheels.
Maybe just a mishap at the factory? Not only is that an excessive amount, but it's not really
a lubrication point either (according to S&G's service manual). And in terms of how much
to apply, S&G's manual states, "a thin, almost invisible layer." Anyway, maybe it was just
a stray glob from the factory. But from what I seen on w2, I'd give this thread a XXX rating.

Thanks for another great and helpful piece of work Gordon.
EDIT: And I spot no corrections worthy of mention. Nicely done.

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Fri Mar 11, 2016 1:35 pm
by jharveee
I have the S and G 6730 and also the La Gard 3330.
Have been told as well, "No Need to touch the Torque Adjuster" as it has been set at the factory to optimum setting.
Of course, being told not to touch it, has made me wonder what will happen if I do.?

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Sat Mar 12, 2016 2:18 pm
by Altashot
Wow Gordon, can't get any deeper than that!
Beautiful write up!
One thing though, you didn't wear your white gloves! :razz:

M.

Re: What Is Inside an S&G 6730 Safe Lock? (EXTREMELY pic hea

PostPosted: Sat Mar 12, 2016 2:59 pm
by GWiens2001
Altashot wrote:Wow Gordon, can't get any deeper than that!
Beautiful write up!
One thing though, you didn't wear your white gloves! :razz:

M.


Figured people would think I was pretentious if I used the white gloves in the pics. So for every pic that might have my hand, I took off the gloves. ;)

:mrgreen:

Gordon