BEST SFIC types

[Trip Doctor]

Aright, so much for that idea I guess . I thought the pinning might have been a bit more restricted and the destance between the shearlines was a lot smaller.

[maxxx]

SFIC A2s are nifty little cylinders. Pop the lid on a pinning kit and your first clue will be there are 25 tiny pins. Its a complex lock. Three shear lines should be easy to pick? Not really, not talking about $10 Kwikset here.

Two will open the lock, but only the Control shear line will remove the core. And it is stiff and hard to rotate even a few degrees. Especially with a special pick.

If you popped the control line on a A2 with a normal tension wrench on a A2 TD keyway, you: are the big kahuna. The ayotolla of rock and rolla. Muffie the magnificent.

[WOT]

SFIC A2s are nifty little cylinders. Pop the lid on a pinning kit and your first clue will be there are 25 tiny pins

Not quite. ALL SFIC, A2, A3 and A4 will have 3 pins per chamber minimum, but can have 4 or more for a master keyed setup.

Two will open the lock, but only the Control shear line will remove the core. And it is stiff and hard to rotate even a few degrees. Especially with a special pick.

Not quite. You're assuming a 4-pin two operating cut and one control cut configuration. There are ONLY two shear lines. The control and operating. Master keying may create additional operating and control depths, but these do not create new shear lines. Shearline is the physically moving line of the cylinder itself and Best locks have two independent shear lines.

Control can be tight even with a proper key especially something that's sat for decades since the last time it was removed. These maybe better off being drilled out. If it's a frequently used lock and worn out, recombinating a brand spankin' new cylinder would be killing two bird with a stone anways.

[Raymond]

Info note: Using an IC specific pick helps the picker focus on the control sleeve but nothing really helps focus on the opening shear line.

WOT? I've worked A2, know about A4, but have never been exposed to A3. What's the differencee there?

Ijust posted this chart on another question. Use it in good health.

BEST A2
Bottom Top Pins Control Bottom
Pins 2 0.025 Cut Stack Total
3 0.038
0 0.110 4 0.050 9 347
1 0.123 5 0.063 8 335
2 0.135 6 0.075 7 322
3 0.148 7 0.088 6 310
4 0.160 8 0.100 5 297
5 0.173 9 0.113 4 283
6 0.185 10 0.125 3 270
7 0.198 11 0.138 2 257
8 0.210 12 0.150 1 245
9 0.223 13 0.163 0 233
14 0.175
15 0.188
16 0.200
17 0.213
18 0.225
19 0.238

[lostlink]

Its a complex lock. Three shear lines should be easy to pick?

There are only 2 (two) shear lines.....................

[lostlink]

Its a complex lock. Three shear lines should be easy to pick?

There are only 2 (two) shear lines.....................

Opps..........WOT already said it..........

[lostlink]

I've worked A2, know about A4, but have never been exposed to A3. What's the differencee there?

The A3 is a discontinued system.......
It is a single step system with key cuts of 0 to 6. The pin sizing is at .018" increments with the number one top pin at .018" which is the downfall of the system. The very slim number 1 pin at .018 would cause problems in the system (as well as a number 1 pin @ .0125" would in the A2 which is why it was never used). Pin stack total for A3 is at .398.

Which is why the A4 was developed @.21" increments..............

.........................

[lostlink]

I've worked A2, know about A4, but have never been exposed to A3. What's the differencee there?

The A3 is a discontinued system.......
It is a single step system with key cuts of 0 to 6. The pin sizing is at .018" increments with the number one top pin at .018" which is the downfall of the system. The very slim number 1 pin at .018 would cause problems in the system (as well as a number 1 pin @ .0125" would in the A2 which is why it was never used). Pin stack total for A3 is at .398.

Which is why the A4 was developed @.21" increments..............

.........................

I mean .021" increments...........

[WOT]

Info note: Using an IC specific pick helps the picker focus on the control sleeve but nothing really helps focus on the opening shear line.

WOT? I've worked A2, know about A4, but have never been exposed to A3. What's the differencee there?

They're all the same in theory, except the pin height increments. Every BEST SFIC is based on 110mil + n*x for bottom pin and n*x for top pins and sum of all is equal to the 398 mils.

Let x be pin's number.

n values:
A2 12.5 mils
A3 18 mils
A4 21 mils

So, A2 would be (398-110)/12.5 = 23.04 --> integer 23
A3 = (398-110)/18 = --> integer 16

The key ALL share the same depth/height for cut #0, then then height decreases by the same increments as above for each cut depth, so you'll likely have to find someone with a Framon #2 to get A3 and A4 keys made since A2 is the most common and I don't think many locksmiths are aware of A3 and A4.

A2 does not have a #1 pin except for the BP and requires a cut depth separation of >2 (but does not require two step progression, so 1&2 can't happen, but 1&4 can. in true two step progression, it would be in INCREMENTS of two, so 1,3,5,7,9 only)

All in all, I believe A3 offers more usable bittings than A2, as A3 allows each and every one of 0 to 6 to be used while often time, A2 is likely set up for two-step progression which only allows five bittings (odd or even) per chamber.

[Raymond]

Thanks for the info. I just did not have any good reference on A3. I had been thinking about using 7 depths, 0-6, and reasoned that since the control sleeve at the pin area is .125 inch thick, that .125 / 7 would equal .018 inch. This system would use a normal A2 0 pin as a no-cut and a A2 9 length as the #6 cut. The other five pins would be in increments of .018. This would make more usable combinations using single step progression versus two-step progression commonly used in A2. Why has it become so outdated? Even an .018 master wafer can be used safely in a lock with tight tolerances.

[WOT]

Thanks for the info. I just did not have any good reference on A3. I had been thinking about using 7 depths, 0-6, and reasoned that since the control sleeve at the pin area is .125 inch thick, that .125 / 7 would equal .018 inch. This system would use a normal A2 0 pin as a no-cut

I'm not following what you're saying. The "0" pin is only avaiable for the bottom pin and A2, A3 and A4 all use the same 110mil pin for #0 bottom pin.

and a A2 9 length as the #6 cut. The other five pins would be in increments of .018. This would make more usable combinations using single step progression versus two-step progression commonly used in A2. Why has it become so outdated? Even an .018 master wafer can be used safely in a lock with tight tolerances.

They're not quite the same. A2 9 =222.5mils A3 6 = 218 mils. You're off by almost 1/200" and that's pushing it.

[lockeymoto]

I learned something new, cool thread. interesting topic

[jpb06080]

Getting back to the earlier posts on this thread, does anyone have any experience with all three of the IC tension wrenches peterson offers? are there any other companies making similar tools? I have the A wrench, and works pretty good on the C and AA keyways (havent tried any others). I'd like to get the other two, but would appreciate any advice from someone who has more experience with them.

[WOT]

Getting back to the earlier posts on this thread, does anyone have any experience with all three of the IC tension wrenches peterson offers? are there any other companies making similar tools? I have the A wrench, and works pretty good on the C and AA keyways (havent tried any others). I'd like to get the other two, but would appreciate any advice from someone who has more experience with them.

I've made one from a street sweeper bristle, but I've never had a success. Grabbing just the control lug is quite hard without inadvertently putting torque on the center lug, which causes the operating shear to bind...

I just opened an SFIC group for you SFIC enthusiasts..
http://groups.yahoo.com/group/SFICLocks/

[Abus]

In all honestly, whether the control shear wrenches work well has quite a bit to do with the "personality" of a particular lock. Sometimes the housing (knob, etc) binds on the control lug a little, which makes picking the control shear line hard, and makes picking the operating shear easy.

Occasionally, you can use a top positioned tension tool and put a very short and shallow control tension tool in the lock at the same time to "select" the operating shearline. Not very often, but I've had it work.

Also, sometimes you can spray in lube to get the operating shearline more freed up than the control.