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#16

Posted: Thu Oct 01, 2009 12:19 pm
by cressy
many thanks for that bit of info phil, its sorted now and runs properly. without knowing that, the mounting point for it looked like one of the mountings for the motor. he he! just waiting for my plinth materials to arrive now!

#17

Posted: Thu Oct 01, 2009 12:21 pm
by pre65
I use a Technics mat on my 401 as mine came without one. As you say they are thick, and fit perfectly. :lol:

The motor/disc do not move, the magnet does ! You will see when you start stripping !

Take photos as you strip down and it will be a useful aid when you put it back together. :wink: I'm glad I did !! :)

#18

Posted: Thu Oct 01, 2009 12:55 pm
by Mike H
So was it just seized up then?


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#19

Posted: Thu Oct 01, 2009 3:14 pm
by cressy
strangely no, on the bottom of its mounting theres a screw and locknut arrangement like a tappet adjuster on a car top end so it can be adjusted. too loose and the control on the top plate wont stay where you put it, too tight and the magnet wont move at all. it was tightened right up, so moving the control moved the entire motor assembly after the springs in the linkage stretched to their limit. i suspect thats why one of the springs was stretched out of shape. it will have been turned to change the speed and instead of the magnet moving, the 'control end' will have moved without the rest of it moving and buggered the spring

the magnet was out of sight underneath the top plate so i didnt even see it was there. clever little arrangement. i think it contributes to the rock solid sound these decks give as i think it forces the motor into giving more torque by resisting its movement without actually touching it. the stall torque on these motors must be enormous!

#20

Posted: Thu Oct 01, 2009 6:24 pm
by Mike H
Interesting, so maybe lubricant dried up? Or someone else has done it up more for some reason.


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#21

Posted: Thu Oct 01, 2009 7:51 pm
by Greg
Hi Anthony,

I'd avoid a full strip down of the chassis unless you are determined to do a very thorough restoration. Generally all the contol linkages should be more or less sound unless some bodger has been messing about. All they should need is an application of grease on any places where there is interference with the chassis or other linkages. The original grease present can be used as a guide. For the pivots I particularly like spray grease because it will infiltrate simple bearings before the solvent evaporates leaving the lubricant as and where you want it.

The only parts you should need to look at are the motor and the main bearing in terms of stripping and reassembly. The main bearing comes out easily and is easily serviced and refitted. The motor is more complicated but well within your capablity. Regardless of what the manual says, the only way to service and lubricate the motor properly including the top and bottom bearings is to strip it down. To aid reassembly, before you remove any drive wheel or other part, always feeler guage it's location to a corresponding surface/component so you can set up precisely on the rebuild. As previously mentioned, worry about that speed control link so as not to damage springs. The 301 motor in terms of service is basically the same as the 401.

I have intended for a while to write up a comprehesive service instruction for the 401 but to date have failed. In the meantime, here are some links you might find helpful.

http://www.ebsystems.1cis.com/g301_m.htm

http://www.ebsystems.1cis.com/images/late01.jpg

http://www.vinylengine.com/phpBB2/viewtopic.php?t=4206

If you explore the links within the Vinylengine post, that should get you to a guide on stripping and reassembling the motor.

Come back if you need anthing else.

Regards,

Greg

#22

Posted: Thu Oct 01, 2009 7:54 pm
by pre65
Ant - a set of BA spanners will make things a lot easier for you !

#23

Posted: Thu Oct 01, 2009 9:32 pm
by cressy
cheers for those links greg i'll have have a good look through them before i do anything more. a bearing strip is a certainty anyway as ive seen enough supposedly good bearings turn out to be either shot or in need of work to leave its condition to chance. knackered bearings'll make even the best deck in the world sound like a pile of crap!

at the moment im disinclined to faff too much other than a bit of cleaning up, simply because everything now works as it should. the only thing that needs anything other than a clean is the platter break. it needs a new pad as the original has perished

only other thing im slightly concerned about is the motor springs as there is some surface rust on them all and judging by the condition of the linkage springs i removed to put the new set in its likely they're past their best by a long way.

buuuuut, all the work is simple errr 'recommisioning work' as now theres nothing inherently wrong with it now. quite why the speed control mechanism was torqued right up so it didnt move is a mystery to me, there doesnt seem to be any reason why.

re ba spanners phil, am i right in assuming you man imperial sized ones? if so i think i can track some down in my grandads workshop, used to be a million of them down there before he passed away

#24

Posted: Thu Oct 01, 2009 9:38 pm
by pre65
BA = British Association.

The BA (British Association) sizes were formulated in 1884 and standardised in 1903. Later it was recommended to use them for all sizes below 1/4" instead of BSW/BSF. They are mostly used in electrical and instrumentation applications and continued in common use in the UK more or less until metrication in the 1970s when its use started to decline. Although odd numbered BA sizes have been made and are listed, they are quite rare. In the UK the even number sizes from 0BA down to 8BA are still readily available from electronic component suppliers such as RS Components, but the smaller or odd number sizes are often only available from model-making suppliers and companies offering parts for restoration work.

My BA spanner set came from my Dad ! :wink:

#25

Posted: Thu Oct 01, 2009 9:51 pm
by cressy
sounds promising for having a look in the workshop then as he made model aeroplanes, the big radio control ones with the little petrol (i think) powered motors. things like spitfires and hurricanes. i'll have a pike about next time im there

#26

Posted: Fri Oct 02, 2009 5:47 pm
by Mike H
If you'd ever had a Britsih car from about 20+ years ago you'd find all the electricals are BA, the remainder being AF with maybe the odd UNC and Whitworth thrown in for good measure. Not forgeting the possibility of the occasional left-handed nut. Phil should know all about them :D


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#27

Posted: Fri Oct 02, 2009 6:05 pm
by pre65
Aha ! LH threads eh ?

Many years ago TVR sent the first (original) Griffiths to a USA motor show, but for some reason they had run out of LH thread hubs for the wire wheels. So they fitted 4 RH thread hubs and gave instructions that no one must actually drive the car.

Of course someone did and (as one would expect) two wheels fell off !! :lol:

Makes you feel a twit when struggling to undo a nut and then finding it's LH thread. I don't think it's very common fitment these days though ?

#28

Posted: Fri Oct 02, 2009 6:37 pm
by Mike H
I hope not ~ tends to be locking tabs and things like that? Must say though metric don't half make things simpler

Yes I've been caught out with LH threads as well, eventually the penny drops maybe should try it in both directions, just to make sure .. and lo and behold ...

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#29

Posted: Sat Oct 03, 2009 2:15 pm
by Ali Tait
All the old panels and switchgear at work(which is almost every site) use BA sizes for wiring connections.

#30

Posted: Mon Oct 05, 2009 6:52 pm
by cressy
anyone got a template for the plinth for a 401? my plinth stuff has come finally so i can start cutting drilling filing and probably bleeding............