edit: I spoke to the tech at gst9 shop and cinching down the 2 jig halves firm is what supposed to do. So I believe that all their jigs are not dead nuts. i was told they have 8 machines that make the jig. Maybe there are variances that result in the trigger housing/rear rail pin to be off a slight amount that causes the rear rail to not be parallel with the front.
Project #1 = all good but the rear rails were .02-.03 lower than front. Ie the holes were drilled a tad too low.
project #2 = Blank drilled in leveled quality drill press with the bit square to the floor like in #1. The rear rail holes on this one were .03 on one side and .02 on the other too far to the rear so the rail pin holes did not line up. WTF!!
Both #1 and #2 rails have same measure from pin hole to rail +/- .002.
I had 2 jigs with 2 frames and the 2 block pins were positioned fine on both frames. After lots of measuring and thinking and comparing I came to the conclusion that the rear part of the jig with the trigger pin guide gets slightly warped once the 2 jig sides are bolted together TIGHT. This makes the rear parts of the jig bend slightly together creating an angle to the guide hole that misses target.
By over tightening down the bolts I bent the jig! Of course after figuring out the above I read through the instructions to find their emission error but they clearly say DO NOT OVER TIGHTEN!!
So there ya go! Attached is a pic of the jig and you can see that the center portion mates up but there is a gap on the outsides. The front dosent matter but the rear does. I had assumed that the jig was flush so never looked when it did it..twice in a row.
I made a post somewhere bitching about polymer80 and their rear rails so I take it back! be calling them tomorrow. Hope this helps others who know it all and dont read instructions fully. But in my defense the jig should be flush! it might be better to just tape this one like you do with P80 jig.
Project #1 = all good but the rear rails were .02-.03 lower than front. Ie the holes were drilled a tad too low.
project #2 = Blank drilled in leveled quality drill press with the bit square to the floor like in #1. The rear rail holes on this one were .03 on one side and .02 on the other too far to the rear so the rail pin holes did not line up. WTF!!
Both #1 and #2 rails have same measure from pin hole to rail +/- .002.
I had 2 jigs with 2 frames and the 2 block pins were positioned fine on both frames. After lots of measuring and thinking and comparing I came to the conclusion that the rear part of the jig with the trigger pin guide gets slightly warped once the 2 jig sides are bolted together TIGHT. This makes the rear parts of the jig bend slightly together creating an angle to the guide hole that misses target.
By over tightening down the bolts I bent the jig! Of course after figuring out the above I read through the instructions to find their emission error but they clearly say DO NOT OVER TIGHTEN!!
So there ya go! Attached is a pic of the jig and you can see that the center portion mates up but there is a gap on the outsides. The front dosent matter but the rear does. I had assumed that the jig was flush so never looked when it did it..twice in a row.
I made a post somewhere bitching about polymer80 and their rear rails so I take it back! be calling them tomorrow. Hope this helps others who know it all and dont read instructions fully. But in my defense the jig should be flush! it might be better to just tape this one like you do with P80 jig.
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