Cushion spring gap

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paul hoogendoorn
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Cushion spring gap

Post by paul hoogendoorn » Wed Apr 15, 2020 6:26 am

The latest sets of KW points I have received have excessive cushion spring gap, some as much as .0020 inch. Although I can manage to tune my coils correctly using my ECCT there is still a concern that erratic cushion spring bounce or flutter can occur. Apparently there was an article in the Jan - Feb 2018 issue of the Vintage Ford Magazine written by Mike Vaughn on how to crimp the cushion spring. Has anybody perhaps got a (soft) copy of this article or point me to a link where I can access same? Thanks.

Paul Hoogendoorn, Port Elizabeth, South Africa.


Humblej
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Re: Cushion spring gap

Post by Humblej » Wed Apr 15, 2020 8:49 am

Lightly tap the rivet with a small hammer.

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Mark Gregush
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Re: Cushion spring gap

Post by Mark Gregush » Wed Apr 15, 2020 10:29 am

I found it took more then a light tap to close up the gap. The Vice-grip tool that was made and sold in the past to crush the rivet, the offset on the bridge next to the rivet is different on the newer points it is closer to the rivet then the older points, so things don't line up. I used a radio chassis hole punch with the smaller dies to do the job and kinda snuck up on getting the correct gap. The wider gap will kinda work, but is not correct. I have a page of instructions that show the wider gap as being ok, but to me they were drawn up wrong in regards to the gap and as an excuse for them being made wrong in the first place. Paul I think maybe you have too many 0's in that number, might it be .020? The correct gap would be in the ball park of .005.
Last edited by Mark Gregush on Wed Apr 15, 2020 12:40 pm, edited 1 time in total.
I know the voices aren't real but damn they have some good ideas! :shock:

1921 Huckster
1925 Cut down pickup


Topic author
paul hoogendoorn
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Re: Cushion spring gap

Post by paul hoogendoorn » Wed Apr 15, 2020 10:56 am

Thanks Mark. Apologies! That should have read .020 gap.Tapping the rivet makes it expand and will restrict cushion spring movement.


Chris Barker
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Re: Cushion spring gap

Post by Chris Barker » Wed Apr 15, 2020 12:05 pm

I have tapped many rivets to reduce the travel to c. 0.005" and I have never had trouble with the rivet swelling.


Allan
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Re: Cushion spring gap

Post by Allan » Wed Apr 15, 2020 9:09 pm

I used a dremel cut-off wheel to notch a .010" feeler gauge strip, so that it could be inserted between the point body and the spring. Then when tapping on the rivet you cannot go too far and get the gap too close. A couple of light taps after removing the strip gets things as close as needs be.

Hope tis helps, Allan from down under.


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paul hoogendoorn
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Re: Cushion spring gap

Post by paul hoogendoorn » Thu Apr 16, 2020 4:17 am

Thanks for the tip Allan. Chris, maybe you can share your method? Thanks.


Chris Barker
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Re: Cushion spring gap

Post by Chris Barker » Thu Apr 16, 2020 5:18 am

I do like the feeler gauge method - I'll use it next time, though maybe a bit thinner than 0.010".

I just tapped and looked until they seemed like my others or until I could insert a feeler gauge alongside the rivet.
The hew ones are usually much too big (0.020"+) but I think 0.004 to 0.008 is fine.


jab35
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Re: Cushion spring gap

Post by jab35 » Thu Apr 16, 2020 12:09 pm

Why isn't the cushion spring gap set correctly and consistency by the manufacturer? I know, this is a rhetorical question, but making these things to spec isn't exactly rocket science ,,,,,. The need to adjust new parts with a hammer or vicegrip just seems wrong to me. Stay safe everyone, jb


Scott C.
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Re: Cushion spring gap

Post by Scott C. » Thu Apr 16, 2020 12:41 pm

The first ones that I bought were all over the place from .010" up to .020". The most recent ones were much better, most were right at .005". But, some still up to .012". What I have been doing to set the cushion spring gap correctly, is using the little brake rivet setting press that the vendors sell. It works really well.


jab35
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Re: Cushion spring gap

Post by jab35 » Thu Apr 16, 2020 2:45 pm

Good tips from Scott and others, thanks. My rant should have also stated that I'm thankful for the availability of these parts; the adjustment is more of an annoyance than anything, and a number of creative approaches have been offered. I've used everything from a $50,000.00 mechanical testing machine at work to a 'calibrated' c-clamp device, to a hammer to get the desired clearance, and correspondingly, the desired coil ttf performance. jb


Harry Lillo
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Re: Cushion spring gap

Post by Harry Lillo » Thu Apr 16, 2020 8:31 pm

Paul, I believe you made a very specific request for the Mike Vaughn article on pages 18 and 19 of the January/February Vintage Ford magazine.
Did anyone send a copy to you yet? It is a very well written article.
I have it open in front of me and may be able to scan and send it to you if you still need it
Harry Lillo
Calgary


Topic author
paul hoogendoorn
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Location: South Africa

Re: Cushion spring gap

Post by paul hoogendoorn » Fri Apr 17, 2020 4:40 am

Yes please Harry I would appreciate a scanned copy. My personal email address is paulhoog@absamail.co.za. Look forward

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