Weston 354

[camsaure]

Hi All, I am trying to convert an old Weston 354 ammeter that is 30 amps to the ten amp style, My 30 amp has only 1 turn of fairly heavy wire. Way back in the late 70s I rewound the amp gauge for a 30 VL and I seem to recall that it used a bit lighter gauge wire and had more turns. Does anyone happen to know he gauge wire and how many turns to make mine a 10 amp? Any help/tips would be appreciated. Thanks, Cam

[exeric]

I don't know if this will be any help but the 10 amp meter on my 1924 Big Chiefs was inscribed with "wind 2 turns", or words to the affect. I can't recall the wire gauge.

[camsaure]

Perfect, Thanks a bunch!!

[Robert Luland]

Be great if ya can throw up some pictures of your work on this as you go along. Bob L

[camsaure]

OK, I will try to take pictures and report on progress. I just ordered some 20 ga enameled armature winding wire. should be here in a couple days. It could be entertaining to watch an arthritic, fat fingered, shakey old fart struggle through this. LOL

[camsaure]

I wonder what the forum did with your picture. I finally got everything I needed to proceed and your picture is gone. DANG

[camsaure]

First carefully/evenly pry off bezel and crystal. then remove the 3 tiny rivets from case.weston1.jpg

[camsaure]

Remove round nuts from back and carefully remove innards from case.weston13.jpgweston2.jpg then you will find a sort of bridge over needle pivot held by 2 very small nuts. Also remove a black cover secured by 2 small nuts. Did I mention to do this in a very safe place so you do not lose or drop any of this hardware?(don't ask how I know). The needle assembly is extremely fragile so carefully lift it out and place in safe place. Then 2 sort of pedestal screws holing the faceplate and remove it.

[camsaure]

The repop face plate has a slightly different opening on lower edge then the original. weston3.jpg To remedy I simply placed the new face on top of the old face, works fine. But I am getting ahead of myself here. The next step is carefully lift straight up a black ferrous horse shoe shaped ring.weston4.jpg You will then find another bridge over the windings. remove it. The 30 amp meter had only 1 turn of heavier wire wound around each of the 2 poles. These wires can be snipped near the solder lugs, be sure to leave enough wire to be able to facilitate unsoldering. I would advise against prying open the lugs, they are brittle and will break off. The old wire is heavier gauge then what you will be using so you should still be able to insert the new wires. You can then slide the wire windings off the 2 poles paying very close attention to directions they are wound so you get your new ones right. There is insulating paper around the poles that will stick to the old windings as they are basically varnished together. So you will need to replace the paper. You need a small rectangular form to wind your new coils around. What I used was the rectangular portion of a pair of hemostats. It is slightly tapered so you can find the portion of it for the best fit. You then slide the windings over the poles and insulating paper. Then apply a bit of insulating varnish on windings.(I would think Glyptal would work for this also. Then you scrape the insulating varnish from the wire ends, trim to length and insert and solder to the lugs. While making sure to have enough clearance on all sides of wire to prevent shorts in the future.weston7.jpgweston8.jpg Then replace the ferrous horse shoe ring.

[camsaure]

weston9.jpg Then reinstall original faceplate and your new repop(I got it from Ebay) on top secured by 2 pedestal type screws.weston13.jpg Then carefully insert needle assembly and be very careful installing bridge across top so you do not damage bearing. If the needle appears to drag across face due to thicker face you can very carefully bend an offset in needle near the bearing.weston10.jpg

[camsaure]

Then replace the small black cover. insert assembly back into case and replace the tiny rivets in case and peen. I first tested with a small battery maintainer/charger set on 12 volts. The gauge indicated 7 amps and reversed connections indicated 7 discharge.weston11.jpg when I checked charger amps with a VOM it read approx. 6 3/4 amps. weston12.jpg Next I set charger to 6 volts and and gauge indicated 3 amps and VOM indicated less then a needle width under 3 amps. I guess that should be close enough and I really have no idea on how to make it any more accurate.

[camsaure]

Thanks to badger34 for details from his Weston 354. wire gauge 20 and four turns of wire. Another item that may be of help is; go to Ebay and get a cheap eyeglass/watch nut driver to help facilitate installing and removing the tiny hardware. Also a good light/magnifying glass is helpful.

[Steve Swan]

Cam, thank you for your outstanding thread! This will be of great help to all who go forward with an ammeter restoration!