BC-1000 Dial indicator spring

[retro-roco]

I've been working on assembling a BC-1000 (SCR-300) from parts I've been collecting for a few years. The recent efforts have been focused on the control panel, and all of the associated parts. Hardware has been refinished or replaced with new.

Reassemby of the channel dial led to the discovery that I was missing a special spring. The manual describes this spring as part #127 - Indicator, Dial Spring (Pointer)

.013" diameter music wire with 15-1/2 turns 1/16" diameter spring formed near one end; overall length is 1-3/4". Hooks formed at each end. The long straight end is painted bright red. - Special

Not exactly something you pick up at Ace Hardware... I decided to try my hand at making one...

The first one worked out ok, so I painted the long leg, and installed it. I decided to make a couple small tweaks, so I made a second. It worked great!
Next project will be the four phone jack seal retainer springs...

[YLG80]

Nice job.
I’ve juste finished with a BC-1000 front plate change back to the Korea war era design.(US marking)
Do you know how many turns should the dial spiral spring be stretched?
If you don’t pay attention to that spring during the dissassembly, dzing the spring relaxes suddenly !
Now that I know, I put a tape on top of the dial and the gear to prevent both of them to move during the disassembly.
But I have never found the info about the number of turns to stretch that spiral spring in the TM.

Yves
BTW If you need parts from a chassis, I have just purchased one to part out in spare parts + jacks in the original rubber protection.

[retro-roco]

Thank you for the kind offer. I am currently doing an external restoration only (making it look good!!)

My chassis has many wiring problems and broken and missing pieces. The main component that is badly damaged is the L3 coil and shield assembly we have discussed previously: viewtopic.php?f=36&t=297530&p=1725397

Everthing beneath the metal shield is destroyed. If you have one available, I can start making a list of the other parts I would be interested in too.

Regarding the spring, I have not found any directions on how it should wound during assembly...

[YLG80]

Thank you for the kind offer. I am currently doing an external restoration only (making it look good!!)

My chassis has many wiring problems and broken and missing pieces. The main component that is badly damaged is the L3 coil and shield assembly we have discussed previously: viewtopic.php?f=36&t=297530&p=1725397

Everthing beneath the metal shield is destroyed. If you have one available, I can start making a list of the other parts I would be interested in too.

Regarding the spring, I have not found any directions on how it should wound during assembly...

I'm pretty sure that your BC-1000 will look very nice, as your restored speedometers

Everything is on the chassis, including L3, all tubes and the crystals. I really don't know why that chassis was discarded.
Only what was attached to the front plate, and the front palte assembly are missing.

L3 coil (2 supports to hold the coil on the chassis are intact)

If you need other parts, let me know, I will carefully remove them from the chassis.
Hmm not sure I will give you the dust on that chassis !

Regarding the spring, I'm not sure it's critical as it is kind of an anti-backlash system.
I have assumed that a few turns were enough.
I'm winding the dial spring approximately as per that photo.

Untouched dial spring

Yves

[retro-roco]

Interesting that your spring appears to be a flat spring, while mine is a round wire type...

I am pretty sure that there is no fixing my L-3 coil...

[YLG80]

Interesting that your spring appears to be a flat spring, while mine is a round wire type...

I am pretty sure that there is no fixing my L-3 coil...
L3 coil-small.jpg

Yes, I have another BC-1000 with the round type spring.
Perhaps the flat type is a French change.

You are right, I meant the two parts riveted on the coil shield. This is a rather fragile assembly.
The coil is only blocked in the aluminum shield by the two square fiber plates on the top and the bottom side of the coil.
The shield itself is fixed on the chassis by means of the two parts like the one pointed by the arrow on your photo.

On my chassis all coil aluminum shields are intact.
If not you could have an annoying micro phonic effect with the chock and vibrations.
Yves

[retro-roco]

Yves

Just sent you a couple photo heavy emails...

[YLG80]

Yves

Just sent you a couple photo heavy emails...

Thanks for the info here !
I have an auto forward from gmail to my primary address but it seems that the attachments are too heavy and my primary server has refused to accept de mail !.
I will examine your pictures directly on gmail?
I return to you asap.
BTW you have a nice and clean chassis dated from 1945(except for the cuts made by a barbarian )

Two remarks after a quick look to your photos:
While your chassis is disassembled like that, take the opportunity to spray contact cleaner into the pots. I usually open them to clean up the carbon track.

Damaged wires going to the jack (green and red): you will need to uncover the jack by removing the black rubber housing and change the wires.
Usually in wartime chassis, the aged insulation rubber becomes like chewing-gum and is useless. I will check if I have the same type of wires in good shape from a French build.

Yves




.

[YLG80]

Yves

Just sent you a couple photo heavy emails...

Hi Kirk, just sent you 3 emails full of images with the missing components identification
Hmm less heavy .
Yves

[retro-roco]

Hi Kirk, just sent you 3 emails full of images with the missing components identification
Hmm less heavy .
Yves

Hmmm... still not seeing the emails. Wonder if they got blocked?

[YLG80]

Hi Kirk, just sent you 3 emails full of images with the missing components identification
Hmm less heavy .
Yves

Hmmm... still not seeing the emails. Wonder if they got blocked?

They were sent from my primary email address.Check your spam box
No warning telling me that they were not delivered.
Yves

[YLG80]

Hi Kirk, just sent you 3 emails full of images with the missing components identification
Hmm less heavy .
Yves

Hmmm... still not seeing the emails. Wonder if they got blocked?

I have just resent the 3 email via my gmail address.
The 3 emails have max 8mb attached files.
They just bounced back to my primary address with the auto forward. So they were sent.

[retro-roco]

Yes, I received them now. Thank you! Will take me some time to figure out your replies.

[YLG80]

I have sent you the requested drawings from the dial light and attachments.
Yves