401 bits

301, 401, plinths and assorted idler stuff
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cressy
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#1 401 bits

Post by cressy »

hi guys, having fixed the amp i can now turn my attention to other things, such as the planned phono stage and colins 401.

the 401 requires abit of cleaning up, maybe a respray as it seems theres some corrosion under the paint on the chassis in some places. i personally couldnt care less about the 'lets keep it exactly the same as it left the factory' approach, so if i do respray it it'll be in flourescent purple (only kidding!). however, im not sure what the base material is. im assuming its a cast alloy of some type so im not sure if i'll need to use an etch primer. any ideas?

secondly, having been over it with a fine tooth comb, the only thing i can find that needs addressing mechanically is one of the springs on the fine speed control mechanism. i was going to replace them all with a solid bar each until i realised the springs were there to decouple the linkage from the motor and stop it feeding back into the chassis through the linkage.

however, my usual sources for slightly odd bits of things have turned nothing up for the springs. does anyone know of a supplier who can source these?

also having spoken to will at owston i have a few tweaks to be getting on with to to the platter (i.e damping various places). any other ideas as i have not dealt with a 401 before? cheers in advance
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pre65
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#2

Post by pre65 »

Go for the purple !
Life is what happens to you while you're busy making other plans. John Lennon

G-Popz THE easy listening connoisseur. (Philip)
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Toppsy
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#3

Post by Toppsy »

Ant,

If I were you I would use an etch primer before spraying. Just try on a small area first to see if you get a reaction. The chassis looked to me to be some sort of magnesium alloy casting, but I may be wrong.

The springs was the only thing I found needed replacing. Have you tried a google search for second hand 401 parts/spares?

EDIT
Ant have you tried Loricraft?
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cressy
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#4

Post by cressy »

no i havent tried loricraft, i'll give them a go, re the chassis, thats exactly what i was thinking, either zinc or magnesium alloy, kinda like a car alloy wheel.
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pre65
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#5

Post by pre65 »

Ant, is this any help ?

http://i111.photobucket.com/albums/n146 ... eck009.jpg

I took a few pictures before stripping mine for a service. (so I knew where it all went when re assembling)
Life is what happens to you while you're busy making other plans. John Lennon

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Mike H
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#6

Post by Mike H »

I doubt magnesium is involved, just an aluminium alloy looks like. Or the sort of stuff model cars were made of.

Could try etch primer, or I would just wire brush it and use acrylic


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cressy
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#7

Post by cressy »

thanks for the replies guys, i tried the loricraft website but it says they dont sell spares unfortunately. im going to email perfectsound as they seem to be able to supply spares, hopefully this type.

next question, partnering arms. i have a jvc ua5045 10" gimbal arm that i'll be trying with it, but this needs a rewire and the sagged counterweight decoupling sorting out. but id like the panels opinion. simply because ive only heard 401s with 4 arms. wills schroeder, gregs with the rega (i forget which one it was, origin live silver?), someones (sorry forgot whose) with the terminator arm and simons with the 'stick' arm. so one of each type i can think of funnily enough but not for any length of time to form an opinion either way (apart from wills schroeder which is always jaw dropping anyway).

and, having an unfortunate lack of time and even less when our new baby is born, around february (im getting lax with the quick builds!) i'll have a right job on trying to make another arm :lol:

i have an interesting plinth idea up my sleeve that doesnt involve a lack table :lol: but i'll report back on that when i get the materials. again cheers in advance again guys
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#8

Post by Bizzie »

I have done a full strip down and respray of my 401 and it's an aluminium alloy and you do need to use an etch primer.

My local auto paint supplier did a fantastic match for the paint colour it a subaru colour I have the can somewhere with the code on it if you want it and they put a small amount or laquer in the paint to give it the same type of semi matt finish.

Unfortunately when I sprayed mine outside it started to spit with rain anI picked it up to move it before the paint had fully hardened and put a mark in the finish with my nail so it needs doing again some time.
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#9

Post by cressy »

cheers for that bizzie, i'll get some etch primer for it. before i start faffing!
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#10

Post by cressy »

does anyone know if 301 and 401 springs are interchangeable? reason being is i found a spring set for a 301 that has 2 large springs that appear to be the idler springs and the 3 little ones that appear to be for the speed adjustment linkage. id rather not waste the cash though if theyre no good. cheers
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#11

Post by Greg »

Hi Anthony,

I've just checked my spare 401 chassis against a late 301 belonging to James which is with me at the moment. Both spring sets are visually identical so you could be onto a good deal there. My word of caution is that when servicing the motor, the speed adjuster is disturbed and the springs on its linkage are easily stretched out of shape. In perfect condition these three springs should be totally compressed when not under tension.

Regards,

Greg
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#12

Post by cressy »

thanks for that greg, that was the problem colin had told me about, one of the springs was stretched and was causing the linkage to not move as it should. re the motor, i think im going to leave it alone for the time being as its working perfectly. the linkages need regreasing and the bearing will get a strip and rebuild out of caution. but the motor is silent and spins up quickly with no vibration thats out of the ordinary so id rather not disturb it. its actually in alot better fettle than it looks
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#13

Post by cressy »

well i replaced the springs on the linkage and it still doesnt work as it should............bugger. i think a full strip and rebuild is in order. cant do any harm though. i'll need to take it to bits to see how the linkage actually works at the motor end. it seems to move the entire motor tighter in to the idler at the moment so acts like a clutch. should it do this? i cant tell exactly how it works without stripping it down............. i'll get my thinking cap out (its abit dusty, hasnt been used in a while :lol: )
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pre65
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#14

Post by pre65 »

The motor speed regulator works by passing a magnet over a steel disc attached to the motor spindle. The position of the magnet determines the amount of "drag" !

Or at least that is how I understand it.
Life is what happens to you while you're busy making other plans. John Lennon

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#15

Post by cressy »

ahhh so is the magnet fixed and the motor movable? or is the magnet on the other end of the linkage so the motor shouldnt move ? further investigation is needed methinks.............
a tip if you wanted to change the mat, i was talking to will at owston who advised that the small lip on the platter makes it a little tricky to get a mat that fits properly. a technics mat from an sl 150 fits perfectly its exactly the same size as a garrard standard mat. and a damned sight thicker so should damp the platter alot better
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