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red16v · 24th Mar 2020, 10:06 am

I cannot really help but offer the following. I have seen (and used!) very similar spool/reel retaining mechanisms on RCA 2” videotape recorders. The mode of operation was that a reel of tape would be loosely offered up to a platter, which would sit between the top of the motor and lower part of the top of the mechanism in photo 1 and then the spool would be pressed firmly down onto the platter. As the spool is pressed down the splines (also shown in photo 1) would spring out and grip the inside of the centre of the spool. The inside of the centre of the spool has a least one vertical groove in it which should engage with the splines - if it didn’t you gripped the spool firmly and twisted it until they engaged. As you initially pressed the spool down (and the splines came out to engage with the inner grooves on the spool) so the top part of the hub sprang out - that is the black part on the top of the mechanism with the three cross head screws in it - it should be quite proud of the spool when a spool is placed on it and pressed down. To release the spool you pressed down firmly on the top of the ‘black part’ with the palm of your hand which caused the splines to loosen and retract and the spool would then be ‘ungripped’, released and ‘jump up’ by a quarter inch or so so that it could be easily lifted off the machine. A variation of this method was to have retractable ball bearings in place of where you have vertical splines. A neat way of doing this which Ampex did not follow - patents maybe?

Might I suggest you peruse this group, perhaps join and ask you question as there is lot of knowledge there from around the world.
http://www.quadvideotapegroup.com/

PS. I have not seen a red Memorex spool in the flesh in all the many years I spent in Videotape. I think it is an early product, later Memorex spools have a foam face under one of the flanges to ease tape handling. If you ever decide to sell it I would’ve very interested!

PPS. If these are what I think they are and do not feature the ‘spring splines’ you could try simply twisting the top of the hub mechanism (the part with the 3 cross head screws) and see if that manually causes the splines to move in/out. The motors do look unsophisticated so they could be an early model?

May I ask where you obtained these bits and pieces from?

24th Mar 2020, 10:06 am	#2
red16v Heptode Join Date: Jul 2006 Location: Winchester, Hampshire, UK. Posts: 638	Re: Two inch tape hub motors identify I cannot really help but offer the following. I have seen (and used!) very similar spool/reel retaining mechanisms on RCA 2” videotape recorders. The mode of operation was that a reel of tape would be loosely offered up to a platter, which would sit between the top of the motor and lower part of the top of the mechanism in photo 1 and then the spool would be pressed firmly down onto the platter. As the spool is pressed down the splines (also shown in photo 1) would spring out and grip the inside of the centre of the spool. The inside of the centre of the spool has a least one vertical groove in it which should engage with the splines - if it didn’t you gripped the spool firmly and twisted it until they engaged. As you initially pressed the spool down (and the splines came out to engage with the inner grooves on the spool) so the top part of the hub sprang out - that is the black part on the top of the mechanism with the three cross head screws in it - it should be quite proud of the spool when a spool is placed on it and pressed down. To release the spool you pressed down firmly on the top of the ‘black part’ with the palm of your hand which caused the splines to loosen and retract and the spool would then be ‘ungripped’, released and ‘jump up’ by a quarter inch or so so that it could be easily lifted off the machine. A variation of this method was to have retractable ball bearings in place of where you have vertical splines. A neat way of doing this which Ampex did not follow - patents maybe? Might I suggest you peruse this group, perhaps join and ask you question as there is lot of knowledge there from around the world. http://www.quadvideotapegroup.com/ PS. I have not seen a red Memorex spool in the flesh in all the many years I spent in Videotape. I think it is an early product, later Memorex spools have a foam face under one of the flanges to ease tape handling. If you ever decide to sell it I would’ve very interested! PPS. If these are what I think they are and do not feature the ‘spring splines’ you could try simply twisting the top of the hub mechanism (the part with the 3 cross head screws) and see if that manually causes the splines to move in/out. The motors do look unsophisticated so they could be an early model? May I ask where you obtained these bits and pieces from? Last edited by red16v; 24th Mar 2020 at 10:17 am.