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MartinHewitt's LG 3390

PostPosted: Fri Feb 09, 2018 10:31 pm
by MartinHewitt
Before I continue with the LG 1800 I'll try a manipulation of an LG 3390. Hopefully my CCG has made no mistake, because getting it open with two identical numbers would really be a disappointment.

Regarding the manipulation ... I can only recommend to make a hole into back cover at the position where the lever nose comes down into the cam gate. That is partly covered by the fence lever control device, but it is possible to look below the FLCD to the lever nose. With this hole you can really have a look and understand how the FLCD works. There are variations in the locks which determine when the lever is lowered and raised. There are different contact points depending on the lowering and raising. The variations are not as big as in a 3330, but I believe they are exploitable when the reading is more precise. I hope a 1/16th of a number will be sufficient.

Re: MartinHewitt's LG 3390

PostPosted: Sat Feb 10, 2018 9:15 pm
by MartinHewitt
Not easy at all. After nearly four hours dialing I mostly know the low areas of each wheel, have some good positions, but I still can't identify for sure any gate. Graphs are also changing depending on dialing a single combination or making a scan. Btw. the left CP is not really helpful and the right CP is in the range of 7 6/8th to 8 0/8th. In the last halve hour of dialing I have changed my method of reading the CP. Maybe that will help with future dialing. I wonder if a should increase the resolution from reading each 2.5th number.

Re: MartinHewitt's LG 3390

PostPosted: Sat Feb 10, 2018 11:40 pm
by MartinHewitt
My last graphs. From right to left: L50/R76/R, L50/R76/L, L50/R/L30, L/R15/L30.

Re: MartinHewitt's LG 3390

PostPosted: Sun Feb 11, 2018 12:04 pm
by MartinHewitt
47 is definitely a gate on w3.

Re: MartinHewitt's LG 3390

PostPosted: Sun Feb 11, 2018 4:40 pm
by MartinHewitt
Open in 353 minutes. 92/16/47. I will look for more colors so that the multiple graphs are not confusing me. Btw. the 6630 is IMHO more difficult to manipulate than the 3390.

Re: MartinHewitt's LG 3390

PostPosted: Sun Feb 18, 2018 3:46 pm
by MartinHewitt
Open in 202 minutes. 19/68/86. Finding a way to make consistent readings is very important.

Re: MartinHewitt's LG 3390

PostPosted: Sun Mar 25, 2018 1:36 pm
by MartinHewitt
Open in 77 minutes. 39/4/75.

Re: MartinHewitt's LG 3390

PostPosted: Fri Aug 10, 2018 10:39 am
by Deadbolt
Did you find any obvious weakness in the 3390 mechanism that could lead to malfunction? My local safe tech have a strong dislike to the 3390, as it is used on ATMs here and give him a lot of trouble as they malfunction. He will not disclose if there are any common faults or if they are different from time to time, suffice to say they are of bad quality and that he does'nt recommend them for my own private safes. Obviously, ATM locks see much use, and they will eventually wear out...

Re: MartinHewitt's LG 3390

PostPosted: Fri Aug 10, 2018 11:04 am
by MartinHewitt
The obvious weakness is the construction of the fence lever control device and drive cam from zamak cast. When the pin on the cam or lever is worn or broken of there is no chance to open the lock. This provides a lot of business to safe men. The reliability of the 3330 was much better, but AFAIK it isn't produced anymore and the 3390 should take its place. The more high end LG locks (1985, 1947, 3332) are much more robust due to to better quality. If you are stuck with 3390 check regularly the condition of the cam, lever and control device (aka tomahawk). I can't give you a recommendation on what "regularly" should be. Spontaneous inspections should always be done when the behavior of the lock changes. (Needs suddenly more force for turning the dial, needs multiple tries to open the lock, and so on.) If you see any worrying wear or defects, the parts should be replaced. As for normal people parts are not so easily available that means probably a replacement of the complete lock. The high end locks can also break, much more seldom. There e.g. the pin mounted on the cam can get stuck and stops to rotate. This increases the likelihood of a malfunction. So a more seldom inspection can't hurt there either.

Re: MartinHewitt's LG 3390

PostPosted: Fri Aug 10, 2018 10:16 pm
by MartinHewitt
Photo of the 3390. Problematic points circled. All thin, moving, sliding Zamak parts. If anything breaks or is worn to much the lock probably won't open because the lever stays where it is.

Re: MartinHewitt's LG 3390

PostPosted: Fri Aug 10, 2018 10:43 pm
by Deadbolt
Thanks! My sample has the "fence lever control device" made out of plastic. Hmmm could it be better than all Zamak? Somehow I doubt it...

Re: MartinHewitt's LG 3390

PostPosted: Fri Aug 10, 2018 10:55 pm
by MartinHewitt
Doubt it too.