The Triumph A 2/4 upgrade mandrel is very rare because most of the time you see an A it has the B upgrade mandrel on it which will fit but you have to move the upper bed plate all the way to the right so the belt will not hit so the screw holding the bedplate down will be all the way to the left and not centered in its lug.
All the upgrade mandrels and feedscrews are stamped. My article below and the copies of the Edison letter should answer all your questions, if not please let me know. I have a Triumph A with a B mandrel on it. No other companies made them to my knowledge. Edison made 2/4 upgrade mandrels and pulleys for the Concert, the early Spring Motor, and the ABC triumphs. Steve I was able to find a copy of a letter Edison sent to his dealers telling about the different mandrel upgrades for the home and triumphs. If the dealers needed a letter, how much more will this information help us? Here are some things that I have found from the letter and myself. The lengths of the triumph feed screws are as follows: The A is 4 27/32" and is marked T D A I and TA on the feedscrew and the mandrel. The B is 5" and is marked T D B I, TBI, or just a large TB on the mandrel and the end of the feed screw is also marked. The C is 5 1/4" and is marked T D C I on the feedscrew and the mandrel. I have never seen a C except for a pulley. The D and E (and F I assume) is marked T D only. The pulley is marked with an A B C or D. Homes: The home is marked H B I, IHB or H A B I for the A & B and H C for C. The home D and higher is marked H D. If you put a Triumph B mandrel on a Triumph A you have to move the upper bedplate to the right all the way to compensate or the belt hits where it goes through the lower bedplate. My Triumph A has a B mandrel on it. I believe the pulleys are the same, and think the shifters on the C kits have the lip like the D and higher does, but I have only seen one home C and one triumph C with the kit so I can't say for certain. 7 or 8 Triumph C's are known and the Home C is very uncommon. Until I saw this letter on eBay (I did not win it but purchased a photocopy from the winner) I did not know they made 5 different ones. If anyone wants a copy of the letter e-mail to them please contact me. Steve >From Terry Baer: The model C used a unique mandrel assembly with "captured" bearing. Picture an early two minute mandrel shaft. Remove the mandrel and turn down the area under the mandrel to about 5/16" leaving the larger 5/8" feedscrew. Now slip on a bearing that is 5/8 OD 5/16 ID. Now slip on a mandrel with smaller 5/16 holes on both ends. Now slip the whole assembly in the top works. ________________________________ From: john9ten via Phono-L <phono-l@oldcrank.org> Sent: Wednesday, January 27, 2016 7:26 PM To: Antique Phonograph List Cc: john9ten Subject: Re: [Phono-L] Edison Triumph A 2/4 minute conversion kit? No access to my books right now, would it be different than the one for the triumph model b? John robles -------- Original message -------- From: Richard Rubin via Phono-L <phono-l@oldcrank.org> Date: 01/27/2016 3:29 PM (GMT-08:00) To: phono-l@oldcrank.org Cc: Richard Rubin <richard_ru...@hotmail.com> Subject: [Phono-L] Edison Triumph A 2/4 minute conversion kit? I have heard tell here and there that Edison, and possible some other companies, produced 2/4 minute conversion kits for the Triumph model A phonograph, but I have never seen one, and I'm not sure I know anyone who has. Can anyone out there confirm the existence of such a beast? If so, have you ever seen one for sale, and what did it go for?
