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Gunner Asch[_6_] Gunner Asch[_6_] is offline
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Default Need 8-36 screw 2-1/2" long

On Wed, 10 Aug 2011 09:16:37 -0700 (PDT), wrote:

On Aug 9, 10:01*pm, "Denis G." wrote:
On Aug 1, 11:46*pm, Ivan Vegvary wrote:





Installing an old mortise lockset into a front door. *Lockset was purchased (quite pricey with door knobs, cover plates etc.) from a restoration hardware place. *They reconditioned all the parts and patinated (sp?) them all to look similar.


Problem: The threaded lock cylinder needs to be fixed from rotation with a radially applied screw that is over 2-1/4 inches long. *The existing threads in the bronze casing is 8-32. *I have three choices:
1) Find a screw of the proper length and 8-36 thread with a fillister head
2) Find any long 8-36 screw and turn down the head to fit the hole
3) Re-tap the threads for 8-32 which opens a whole world of screws.


The problem with option 3 is that all of my 8-32 taps (I have over 50) are about a 1/4 to a 1/2 inch too short. *Have any of you successfully lengthened an existing tap? *I have mig, tig & oxy but am worried about axial alignment on the tap extension. *


What are the probable result of re-tapping an 8-36 to an 8-32 in bronze? *Will I end up with a crappy loose thread fit?


BTW, tried McMaster-Carr and Fastenall. *At McMaster I cannot find 8-36. *At Fastenall, I do find 8-36 but maximum length is 1-1/4 inches. *I would need to buy quantity 100 but at least I would get to practice my screw-lengthening skills which should be easier than tap-lengthening.


All advice appreciated.


Ivan Vegvary


McMaster Carr lists a carbon steel 8-36 die for $11.80http://www.mcmaster.com/#dies/=djwfb3- Hide quoted text -

- Show quoted text -


Which was what I was going to suggest, make one. This is what lathes
are for. Chances are you only need a short length of thread at the
end, the rest just needs to be clearance sized for the hole. 8-36 is
a standard thread, just not used a whole lot. Only other place I've
seen that thread is on GI M16 cleaning rods.

Stan


For a thread that long..Id use the die instead of trying to cut the
thread.

Deflection would be a killer


Gunner

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