You are here:

Locksmithing/Vintage U.S. Post box combo


Antique U.S. Postal Box
Antique U.S. Postal Bo  
Hi Andy,

I am hoping you can help me out with this, I'm sure simple, antique mailbox. We purchased the house six years ago and discovered soon after this antique mailbox tucked away in the wall of a spare closet. Obviously once used by prior owners as a safe of sorts.  Every so often I tinker with it trying to figure out a combo. It is built in and to remove completely would mean taking down the wall. I have looked on the Internet and not found much info on these boxes. I was wondering if you knew how many letters would be used in the combination. Or which way to turn to get to the letters. In the past I have tried blindly to figure it out. Any help about this style rotary combination lock would be much appreciated. I will add a picture in hopes it will help you identify it.

Thank you in advance!


First off, I don't specialize in or work on postal box doors.  As far as not finding much info concerning them, the internet only searchs based on the words "YOU" use to describe the item, if you don't correctly phrase an item the results may be limited.   Phrases may not be what or how YOU would describe an item, but you have to anticipate how someone else my phrase it.

I did a simple search for "antique postal box doors" and was rewarded with around 11 million possibilities.  Amazing to me is everyone using the word "vintage".   Sorry but this is one of my pet peeves.  The word vintage has to do with the age of a wine harvest or bottling of a particular harvest, as in the year of the harvest.   While it does have to do with "age", I'm not one who goes for the "bastardization" of a word, simply because a lot of people use it to describe "old stuff".   So while your door might be an antique (over 100 years old), or a collectible item, it is NOT a "vintage" piece.
Again I'm not chastising you for the use of the word, as it is being used by everyone to describe ANYTHING slightly old.   I guess I'm simply more of a purist.   The other word I hate is the word "Patina".  This word is REALLY over used by snobs in the antique world, who have no idea of what Patina actually is, which is the greenish oxidation forming on copper or brass objects.   While some items may look better with this color, oxidation is NEVER a good thing, for instance RUST is a similar oxidation of steel or iron, but no ones says what beautiful "rust patina".

Again sorry for my slight diatribe, this usually happens after a particularly long week.

Back to YOUR subject.   Without having the door in my hot little hands to figure out, I'm going to have to take a guess on its operation.   Most simple locks like this generally have 3 numbers or letters, the dialing sequence would be either LRL or RLR.   While there might actually be two combinations which open the lock, I would stick with one sequence for now.   Once you get it open, you should be able to figure out the other.   I'm going to recommend starting out with RLR with the following sequence:

3 times Right to the first letter,
2 times Left to the second Letter,
1 time Right to the third letter - stop - turn or slide small knob.

Note:  left is counter clockwise, Right is clockwise.  DO NOT count the revolutions of the dial, count the individual letter as it arrives at the 12 o'clock index mark.

with a total of 26 letters this would give you approximately 17,576 possible combinations to try.   By dialing the first and second letter, and then trying each letter for the third letter while turning the knob, you can cut your dialing down significantly to around 700 possible combinations - plus the third letter.   You should be able to run through all these in a couple days.   Set up a spreadsheet with all the possibilities so that you can keep track of where you are.

You can also check out "antique Postal Box doors" to see if this helps.

Again sorry about the diatribe, but the misuse of these words, sometimes drives me nuts.

Hope this helps,  


All Answers

Answers by Expert:

Ask Experts


Terry V. Andreasen (Andy)


Safe and Vault related Questions; Antique Safe Repair and Restoration; With over 42 years in the Safe & Vault industry, if I can't answer your question I know where to get the answer. Current Project: Restoration of an Ely Norris Cannonball Safe from the early 1900's. Will answer Safe & Vault related questions concerning age, value, restoration, moving, opening & repairing, parts, operation and history. Note: It is not my intention to teach you to open safes or to provide information which may aid in the unlawful opening of a safe. I will not give out drill points or information which I deem inappropriate.


44 years in the Safe & Vault Industry. Owner and Service Manager for one of the largest Safe & Vault companies on the West Coast. Graduate of Lockmasters Safe Lock Servicing, Safe lock Manipulation and Safe Deposit Lock Courses. Graduate of Locksmith Institute. Certified Instructor for the California Locksmith Association teaching Basic and Advanced Lock Servicing, Basic Safe opening and Repairing. Factory Trained by AMSEC, LORD Safes, LeFebure, Mosler, KabaMas, LaGard and Sargent & Greenleaf Author of "The Coffee Table Guide to Antique Safes".

SafeCrackers International and the National Antique Safe Association Safe & Vault Technicians Association (SAVTA)

The Coffee Table Guide to Antique Safes

Graduate of Locksmith Institute 1972 Graduate Lockmasters Safe Lock Servicing 1974 Graduate Lockmasters Safe Lock Manipulation 1975 Graduate Lockmasters Safe Deposit Lock Servicing 1985 Instructor Certified - California Locksmith Association - 1985 Factory trained by AMSEC, MAJOR, STAR, Johnson-Pacific, Kaba-MAS, Allied-Gary, ISM, Lord, Brown Safe, EXL, Mosler, Diebold.

Awards and Honors
2009 - 2015 - Listed in AllExperts Top 50 Experts. All Expert Categories - Safes & Security Containers, Locksmithing, Antique Safes. Retired US Army Chief Warrant Officer (CW4), with 39 years of total service. With numerous awards from Vietnam, Desert Storm and Operation Iraqi Freedom. US Navy - 1971-1981 US Army Reserve 1984-2013 US Army Retired

Past/Present Clients
US Secret Service, FBI, BATF, Local Law enforcment agencies, Diebold, Hamilton Pacific, Red Hawk Int., Chubb International, Bank of America, Wells Fargo Bank, Mechanics Bank, El Dorado Savings Bank, many Credit unions and smaller banks. McDonalds, Togos, BurgerKing, TacoBell, Carls Jr. FoodMaxx, SaveMart, Lucky's, Albertson's, Raley's, Safeway, NobHill, Bell Markets, PW Markets. Great America, Century Theatres, Cinemark Theatres, UA Cinemas, and many homeowners and small businesses. Provide warranty service for lock and safe manufactures. Service Area is Northern California (Fresno to Oregon and Western Nevada)

©2017 All rights reserved.