Deflection in new magnet clamp plates T 3277 - 0.008" - fix suggestion

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Model T Ford Forum: Forum 2011: Deflection in new magnet clamp plates T 3277 - 0.008" - fix suggestion
Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dare on Tuesday, December 13, 2011 - 06:56 pm:

Hi, l started to gap my magneto this morning and find in getting close, that the new magnet clamp plates ( T 3277 ) are made with a 0.008" deflection in the center, meaning that the leading and trailing edges are higher than the center, 0.001" or even 0.002" l could live with but eight is too much, can anyone advise a remedy please.

Cheers David.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Richard Gould on Tuesday, December 13, 2011 - 07:24 pm:

I've filed them in the past carefully aligning the file with the adjacent clamps. If you have a lathe with a large enough swing, you can turn the flywheel by using two trans shafts same as you would when balancing the flywheel.
You could simply pound the ends down with a hammer, or you could remove them and press them flat or even file them individually.
You will always have some unevenness in the height of the clamps, including clampt tilt; thats the nature of the beast. When setting gaps you have a pretty wide range of settings, .025-.040", so you should be able to get them within spec.
One thing to note, sometimes its not the clamp but the way the magnets sit or the variation in magnet height that causes uneven clearances.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ron Patterson-Nicholasville, Kentucky on Tuesday, December 13, 2011 - 07:38 pm:

David
I help folks rebuilding Model T flywheels and have heard your complaint about reproduction magnet clamps before. Replacing the reproduction magnet clamps with original Ford parts has always solved the problem.
I have done no research in this area, but I am beginning to think, once again, we have a poorly researched and improperly made reproduction part?
Did the reproduction magnet clamps come in a white plastic bag with the words "Antique Ford Parts" in a blue circle?
Ron the Coilman


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dare on Tuesday, December 13, 2011 - 08:21 pm:

Hmmmmmmmm, how do l not answer without offending someone ???
The originals that came off the car, had been sitting in a sump of rusty water for some years and well past any use, very very pitted., strangely enough the flywheel and most magnets seem to have come thru unscathed !!!!


David.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Erik Barrett on Tuesday, December 13, 2011 - 09:44 pm:

I have probably twenty five pounds or better of original magnet clamps. May I send you some with my compliments? I'll never use them all.
It has been our experience that many repro parts are inferior to good originals.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ron Patterson-Nicholasville, Kentucky on Wednesday, December 14, 2011 - 03:07 pm:

David
I did some asking around on your question. In this case my white plastic bag comment is off the mark. I have never had occasion to use the reproduction magnet clamps and was unaware of the common knowledge that the repro clamps are not as strong as originals. The two parts sellers I spoke with recommended always using original Ford clamps.
Part of your problem may also be the procedure you are using. Under the right circumstances it is possible to slightly deform the sides of even original parts.
From my experience it is important you make sure the magnets vee is seated as close as possible against the large bolts, the tips of the two adjacent magnets are as close as possible against the magnet clamp screw for support and the spools are not damaged. Unless damaged you can reuse brass spools, but used aluminum spools will commonly break when tightening the screws or pounding upon the ends of the magnets as Ford suggested. A combination of too much tightening and the tips of the magnets not being properly supported could your trouble. The clamp screws are brass and should not be over tightened and must be peened.
Hope this helps.
Ron the Coilman


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dare on Wednesday, December 14, 2011 - 05:37 pm:

Erik, l thank you very much indeed for your offer, but will you let me pay the postage to way down here.

Thank you David.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dare on Wednesday, December 14, 2011 - 05:41 pm:

G'day Ron, yes the bolt is hard up against the V in the magnet, held it in place firmly down against the bolt as it was being tightened......
I have to say a big thank you for your posting a month or so ago about giving the magnets a good hard smack, 3 perfectly good looking magnets ( so l thought ) after being hit/struck, showed rust and small cracks well within the magnets V , replacements obtained and charged, wow thats easy when you know how.

Cheers David.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Erik Barrett on Wednesday, December 14, 2011 - 09:30 pm:

If you need these things I would be happy to ship them to you for whatever it costs to get them there.
Fordially, Erik


Top of pagePrevious messageNext messageBottom of page Link to this message  By Allan Bennett on Thursday, December 15, 2011 - 02:41 am:

David,

I had occasion to rebuild a flywheel once which a profesional balancing outfit had re-assembled incorrectly. I got the heights close and got discouraged trying to get that last .005" I solved the problem by taking it to the local engine re-builder and they faced the keepers level on their flywheel grinder. Perfect! Just get them close first so the grinding takes the bare minimum off.

Hope this helps.

Allan from down under.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Dare on Thursday, December 15, 2011 - 08:36 pm:

G'day Allan, went a little further than that, began to measure the magnet heights from the back of the flywheel to top of magnets, quite a variance, the repro T3277 plates didn't help either making variances more so.
Like mentioned, l'll obtain another shaft and have the magnet areas where the plates affix to all machined to true, then an original set of plates on a good known true surface should see me to within a "bulls roar "..

Hopefully that plan seems do-able.
Would appreciate any advise to the contry on my plan.

David bulls roar


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ron Patterson-Nicholasville, Kentucky on Thursday, December 15, 2011 - 11:44 pm:

David
It is important to remember you are trying to index the magnet clamp height with the crankshaft mounting flange.
1
I frankly think your making this too complicated.
Try to borrow a KRW magneto gap gauge in 'stralia or make your own (there are homemade versions of this tool shown on the this Forum), follow the method in the Ford Service Bulletins and be done with it.
Ron the Coilman


Top of pagePrevious messageNext messageBottom of page Link to this message  By Allan Bennett on Friday, December 16, 2011 - 07:17 am:

David, Ron has nailed it. The magneto gap tool indexes the magnet heights to the flange which bolts to the flywheel, as it should. What you propose may not be true to the machined centre of the flywheel, and it will still be difficult to get all the heights the same.

A flywheel grinder indexes from the machined centre of the flywheel. Skimming the clamps means they are absolutely true to that centre.

Allan from down under.


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