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Question about how to use Feickert Protractor

Greetings from Oregon,

I'd been following the discussion about the Feickert Protractor and finally decided to order one.  I'd been using the GeoDisc for setup, and I wanted something a little more precise.  I have been working with the protractor this evening, and the directions on the second step are not entirely clear.  The first step is easy enough - set up the protractor with the gauge pin over the pivot point (easy to find on a unipivot) and adjust the cartridge to the bulls eye in the geometry you want (I'm using Baerwald).  Moving to step two things become unclear

My first question:
Step 2 says "..we don't need to aim over the pivot point anymore. Please rotate the Protractor so that the stylus tip touches the cross hairs at step 2."  The picture shows the stylus sitting right on the target.  Correct me if I'm wrong, but that's not physically possible.  The cross hairs at step 2 are a fixed distance away from the cross hairs at step 1.  There's no way to rotate the protractor to make this happen.  You have to move the tonearm over to step 2, right?

My second question:
Assuming that I'm moving the tonearm over to the lines for step 2 on the protractor, should the stylus fall right on the bullseye as it did at step 1?  Mine doesn't, but I assume there's nothing I can do about it without having the whole tonearm assembly remounted.  It's a VPI Prime, which doesn't appear to have any adjustments for pivot-to-spindle distance.  

I hope the questions make sense, as it's not easy to explain without having the protractor in front of you.  Hopefully, someone with experience using the Fleickert can help.  

Thanks for any advice!
Scott
  
smrex13
smrex13 OP
423 posts
 
Thanks for the quick response.  I'm still a bit confused about a couple of things - maybe I'm just having an off night :).  First, I don't think I can change the P2S distance on the VPI Prime, at least not that I can see.  The manufacturer recommends 258mm, and the measurement on the protractor is 261mm.  

I'm not sure I explained the problem clearly.  According to the instructions, the first step (it doesn't mention the P2S) is to place the gauge pin over the pivot point and then place the cartridge on the lines marked "Step 1" (actually printed on the protractor itself) to adjust the overhang.  I don't have any problem getting that dialed in with a little patience.  

So, once I have that dialed in, it asks me to move to the lines on the protractor marked "step 2" (which are on the outisde part of the protractor) by rotating the protractor.  However, the protractor only moves in a circular motion, so as long as the stylus is over the lines marked "step 1" it can't ever be over the lines marked "Step 2".  It's like placing your stylus over track 3 of a record and then trying to rotate the record until your stylus is over track 2.  You'll just go in circles.  You have to move the tonearm over to "Step 2", presumably without moving the protractor, to make sure that the arc is correct.  Or am I missing something?

Here's a pic 
 http://www.maestrogarage.com/data/maestrogarage/product/feickert_protr_1.jpg

Sorry if I'm just dense....

Thanks, Scott



drrsutliff
299 posts
 
Yes you move the tonearm to the crosshairs in the second step.  The first step is to get the overhang correct.  Rotate the protractor some and swing the arm out to step two to set the alignment at the second point.  You are then checking the cartridge (stylus) alignment at a second (null?) point.  The cartridge should ultimately show correct alignment at both points and point 3.  To move from one to the other requires rotation of the turntable platter (alignment jig) and moving the arm.
smrex13 OP
423 posts
 
@drrsutliff thanks, that makes sense.  I'll give it a shot this evening and see how it works out.  
lewm
6,770 posts
 
If the factory recommended P2S for your tonearm is 258mm, and if you are reading 261mm with the Feickert, then you probably should investigate whether you can loosen the joint between the vertical shaft at the pivot point and the arm board, in order to move the pivot so as to comply with the recommended P2S.  This ideally would be done BEFORE proceeding with any additional steps.  Check the underside of your arm board.  You should see a large nut or some other fastener that holds the tonearm in position in the horizontal plane and that would allow some movement of the tonearm pivot, if you loosen it a bit.  Without correcting the P2S, you may have some difficulty achieving Steps 2 and 3. (Or you may not; there is usually some margin for error.)
larryi
1,972 posts
 
The Feickert can be used as either a one-position protractor (locked in place and not moved to make the adjustment-easiest use) provided that the exact pivot point can be determined and the arm is pointed exactly over that point.  Alternatively, you can use the twin null point grids for any given alignment scheme, but, you have to then move the protractor or rotate the platter and determine for yourself how to move the cartridge back and forth and side to side so that it can fit both the inner and outer grid (provided of course you move the protractor when going from one position to the other).  If you use the protractor as a single point protractor, the result is correct when the adjustment also works when you use the two grid part of the protractor.  A lot of people don't like the two grid approach because of the need to move the protractor and one can get confused as to which movement will be needed to get closer to a fit at both positions.  The two grid approach requires more trial and error to get a good alignment, but, ultimately, correct alignment is assured only when the two grid approach is a perfect fit.  With the one point alignment, you have to achieve perfection in locating the pivot point, something that is not often easy to achieve.
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