Armature/coil Spacing

Stealth Ninja

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Can some one shed some light on this for me please? what should be the size of the gap between the armature bar and the coils? Im thinking a around 2mm from the info Ive found on here. I was reading a tuning guide and he was talking about "shimming" the underside of the coils the close the gap, but from what Ive read on needle depths, pushing the armature bar down to see the length of needle that protrudes, I would have thought 2mm. can any one help? :icon_confused:
 



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troub1edsou1z

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Can some one shed some light on this for me please? what should be the size of the gap between the armature bar and the coils? Im thinking a around 2mm from the info Ive found on here. I was reading a tuning guide and he was talking about "shimming" the underside of the coils the close the gap, but from what Ive read on needle depths, pushing the armature bar down to see the length of needle that protrudes, I would have thought 2mm. can any one help? :icon_confused:
can you be more specific? it seems you are descibing 2 different things. 1 bieng the shimming of coils. typically this is done so that when the abar is pressed down it hits flush against the front coil, while haveing a small gap at the rear coil. the smaller the gap at the rear coil the better. ideal is about the thickness of a business card, but you never want the abar touching the rear coil. the other thing your talking about im a bit confused on. are you refering to the airgap (distance between bottom of abar and top of front coil) which in turn helps determine your stroke (distance the abar travels from highest point to lowest point), or the length of needle you want protruding from tube with abar pressed down. your needle depth can be 1.5-2mm
 

Stealth Ninja

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Yes thats whats thrown me. In the guide it wasnt clear that it was only the rear coil that had to be shimmed and I was under the impression that it was both. So i was confused as to how I was going to get a 2mm length of needle if there was only a 1mm gap on the front coil. Now youve explained it in clearly it makes alot more sense, thanks.
 

Leighton

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What is the air gap when a bar isn't depressed to coil with contact screw touching for a shader
 

Leighton

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What is the air gap for a shader when armature is at rest without the contact screw touching
 

TexasPT

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air gap where? Obviously if the contact screw isn't touching there is an infinite amount of possibilities. If you mean between the top of the coil and the armature bar, that depends on rear spring tension. If you mean between the spring and armature bar...again, too many variables.

I don't think this question can be answered the way it's presented...sorry.
 

Warhorse_Tattoos

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Yes thats whats thrown me. In the guide it wasnt clear that it was only the rear coil that had to be shimmed and I was under the impression that it was both. So i was confused as to how I was going to get a 2mm length of needle if there was only a 1mm gap on the front coil. Now youve explained it in clearly it makes alot more sense, thanks.
You do shim your front coil to get contact before it hits the rear.