synchronar magnets

[clockace]

to all synchronisti's: the slider magnets seem to have varying degrees of magnetism and seem to be somewhat difficult to recharge. i have found a source of permanent magnets in almost to perfect size. they are a neodymium material in 1/16" x varying lengths. i got some in 1/4' length and some in 3/8' length, which is the exact length of the slider magnets. because they are smaller in dia you will need a carrier for them. i have used 2 things. one a brass rod about .080" in diameter which i drilled to hold the 1/16" magnet. the other is a piece of s/s tubing i got at ace hdwe store that is .083" in dia. it has a 1/16" bore. perfect. cut to a 3/8" length it is just the thing to replace the older magnets. however, since these magnets are more powerful they are a bit too long. the reeds will come on with the slightest movement of the slider. in a collet on the watchmakers lathe with a carbide graver i shortened the magnet by about 1/16-3/32". insert in the tube and center it. with a drop of loctite it will stay in place. you may have to experiment with the length. they are not expensive. 10 of them cost $2.80 + shipping. the web site is: www.kjmagnetics.com they have no minimum order and you can order online. regards, peter i don't know why my pictures are so crummy. suggestions?

[retroleds]

.... i don't know why my pictures are so crummy. suggestions?

Pete:
Your picture is only 150 X 200 - too small for any good detail. Capture and/or crop your photos to 600X600 at least. The website info section has more on using ImageShack here. http://www.dwf.nu/viewtopic.php?t=1868

[Sully008]

Peter,

Is this the magnet you purchased?

http://www.kjmagnetics.com/proddetail.asp?prod=D18

I'm just wondering if you actually need the sleeve since the magnet is stronger? Still waiting for those "v60s" to arrive, I haven't forgotten. Stupid cross-border shopping, takes forever.

[bucko170]

Clockace/Pete,
The photo's look ok to me, there are some nice photo's on your Image shack profile, especially like the Sinclair photo's - first time I have seen one that close up and in that much detail, the picture of the analogue is intriguing, what is it?

[Synchroserious]

[quote="clockace"] the slider magnets seem to have varying degrees of magnetism and seem to be somewhat difficult to recharge.

If you have a strong horse shoe magnet with North and South poles gapped about 1/4 " it is real quick and easy to recharge the original alniko magnets.Sometimes flipping the poles arround in the slider or using the magnet on the other side makes it all work better.

Quote,clockace
i have found a source of permanent magnets in almost to perfect size.however, since these magnets are more powerful they are a bit too long. the reeds will come on with the slightest movement of the slider. you may have to experiment with the length.

This experimenting is important,especially on a MK IV. If the switch is too sensitive it will briefly turn on the "away" reed switch when you don't want it to, simply from letting go of the slider while held"toward".
Example:If you are in stopwatch mode and have the left slider "away" displaying running seconds/10ths/hunderedths and want to stop the split timmer on the right the spring back action of the slider(in the case of an over sensitive switch) spring will send the watch back into watch mode.

There is a low supply of the original large magnets. So if one can make their own ,GREAT In any case the alnikos that i charge up and install on modules i make will always stay charged enough to work.When first sent out there is extra "play"or sensitivity but not too much so that after some years when the magnets weaken there still will be enough travel to activate functions properly.It would then require sliding a tad further to activate thats all.If however a high strength magnet is slid over and arround the top of a watch already assembled you could cause all strength in one of the poles to be too weak and that would be the only reason to need to recharge them.(same thing would be true with a Neodymium)

One thing my dad did not like on MK I and MK II,s was how the Ragen staff used reeds that had to be soldered too close to where the lead seals to the glass.Not only does this run the risk of overheating and breaking the seal due to the glass and lead having different coeficient of expansion rates, it also makes the reed more prone to breaking from a shock.He also discovered that a supplier had sent Ragen some with a tiny spec of glass inide the tube from an error in manufacturing them.Of course everything tested fine but all of a sudden one day (usualy months) after it was sent out that spec of glass would lodge itself between contacts and cause it be an intermittant switch.The first clue was that shaking your wrist would dislodge the spec and the reed worked fine again,that is until it found it's way back between contacts at a later date.

Reedswitch improvements made since 1985 FAQ's

Are the reeds used smaller than the old type ? YES
Are they soldered too close to where lead and glass seal? NO
Are they a better quality reed ? YES
Can they be adjusted so that even a weak alniko magnet will activate them? YES
Are they less breakable than the old type reeds? YES
Rateings:Reed used with battery underneath PU 15/20
Reed used with no battery underneath PU20/25

[clockace]

hi howard, i wondered how to recharge the magnets. i now need to locate a horseshoe magnet like you describe. i have found that flipping the magnets over or on the other side will work. the one i am having trouble getting to work consistently is the rear magnet. there often times does not seem to be enough travel on the rod to activate the switch. the module i just switched the chip on is like that. the date will not set even with the magnet off the rod. i did finally get it to advance by using the neodymium magnet by itself. i suspect the rear magnets have lost enough of their charge to not effectively work the switch. peter