PHBH Slides between 40 and 45

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storkfoot
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Fri May 17, 2013 12:19 pm

Am I correct in assuming that you can't buy 41, 42 etc but it's normal to modify a 40 with a dremel to achieve the desired effect?

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Angry Bloke
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Fri May 17, 2013 1:12 pm

Thats what I'm just about to do Paul ,although as the difference between a 50 and 40 is only approx 1.2mm I was going to use a fine file to ensure the cutaway remains flat. :D
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coaster
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Fri May 17, 2013 1:20 pm

Is there any guide for how much to remove to achieve the different stages?

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Angry Bloke
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Fri May 17, 2013 1:40 pm

coaster wrote:Is there any guide for how much to remove to achieve the different stages?
Ive not seen one but I have a new 40 and 50 at home so was intending to measure and pro rata the results -

I will post the measurements when I get home ;)
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storkfoot
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Fri May 17, 2013 5:44 pm

That's the problem. You are dealing with a difference of 0.5mm from the base to the top of the arc. Therefore, it is 0.1mm you need to take off at the top of the arc to make it a 41. There isn't much scope for error!

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coaster
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Fri May 17, 2013 6:12 pm

storkfoot wrote:That's the problem. You are dealing with a difference of 0.5mm from the base to the top of the arc. Therefore, it is 0.1mm you need to take off at the top of the arc to make it a 41. There isn't much scope for error!
I don't know about a fine file, it sounds like a calloused finger would be rough enough.....some fine emery at least :?

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Angry Bloke
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Fri May 17, 2013 7:58 pm

It's less than I thought, the cut out on a 50 is 5mm and on a 40 its 4.1mm ;)

Lets say its a 1mm difference to allow some tolerance on my vernier

So presumably on a 45 its 4.5 , 42 =4.2 etc

As Colin says you could drag it across a 5 o'clock shadow and shave .1 mm off :D

I'll try some fine emery and see how it goes :)
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warts
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Fri May 17, 2013 9:43 pm

When I was doing this with 36 PHF Del Orto's, I just turned a smidge off the bottom of the slide. This was dead easy and repeatable on a lathe with a digital read out. Which was just as well as I had two to do each time.
It was easy to detect the effect too.
Maybe the Del Orto manual has these dimensions, but I don't recall being aware of them when I was doing it.

storkfoot
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Sat May 25, 2013 11:45 am

Well about 10 or 15 passes with a small flat file, finished off with a very fine emery, and I have a noticeable leaning out of the flat spot I was trying to get rid of. Not completely gone but I am loathed to take any more off. With hindsight the original idea of a dremel would have been a disaster :-)

Adam_Winstone
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Sat May 25, 2013 11:57 am

I'd modify mine with a phone, card and call to a Dellorto dealer. As stated, there is little room for error.

Adam

PS - The irony being that I modify Dellorto needles by hand so really am in no place to make such a comment ;)

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