LNL AP problem with consistant seating depth

[hexbasher]

ok. i ended just ripping my LNLAP apart and taking the subplate into work

subplate measures 0.942 and the step on the drive hub measures 0.932 = 0.010 play...i double checked the 0.010 by checking in on the granite with a height gage

i then made a 0.009" bronze shim on the lathe

not hard, not impossible, but you need some know how to do this

assembled:

WORD OF WARNING!
haha, i gouged my sub plate!!

i only brought my #16 shell plate into work because its the only one i've have yet to use (i own a #8 and #10 but i have yet to use them due to lack of small pistol primers)

my #16 shell plate has 0.005 bow on the back face (the center is thinner compared to the outside edge)

this gave me a hell of a problem fitting (ie sanding) my bronze shim till things wouldnt bind...i honed little chamfers on my #16 shellplate

^^^these little edges are what gouged my subplate because they dig in with the amount of bow

im going to check my other two plates at home tonight to see if they are bowed too..i may have to call hornady over this

i managed to smooth things out a bit, but right now there's definitely a high spot when i rotate my shellplate...i'll hold off on any more work until i get home and check the other plates..but i am going to prussian blue this to find that high spot...

i should have check this the second i started to fit the shim...stupid me rushing my side-projects

solutions:
-call hornady and replate #16 plate if out of spec
-a second shim is needed inbetween the subplate and shellplate (if my other plates are flat)
-grind/turn my #16 flat...(if other plates are flat)


man, this takes me back to my days of MRO machining

 

[hexbasher]

i ended up lapping the back side of that #16 plate after i checked it again on the granite

besides the 0.005 bow from center to edge, the other edge was all over the place (+/- 0.001") which was also added to the gouging/high-spots

the depths from the top side to the steps (where the shells are held by) where +/-0.01mm (too lazy to grab my inch depth mic) which is pretty good



i got the feeling i may have to "tune" each plate

 

[nevanevan]

I am still waiting on my arbour kit to arrive and loading must be accomplished, however I have posted a picture below that might counter my orignal opinion. The tallest feeler gauge I can push under the shell plate with minimum resistance is .004-.005 thou on every stage of the press. Does this mean that shimming the arbour will be a useless result? Maybe I received one of the better presses that doesn't have .014 thou clearence, or is this the absolure wrong way of measuring this kind of information?

 

[hexbasher]

nevanevan

because your sheelplate is flexing around, shoving a feeler gage under the plate is not an accurate measurement. you really need to pull the subplate and measure...a normal pair of calipers is all you need to measure it


as an update to my last post, my #8 shell plate is flat within 0.002" and my #10 is 0.0015".....guess my #16 is a bit off...

 

[nevanevan]

So I tore apart my press today (was actually super easy to do) and got some measurments. It appears that using my standard caliper I was able to measure 0.942" on the drive axle below

And 0.935" on the subplate, I placed the subplate on the flatest peice of 1/2" aluminum that I have just lying around, image below

I know the method is crude, but it looks like I could maybe shim about .004-.005" of clearance out of the press. Hopefully shims arrive next week and I will update. If anybody sees that I measured incorrectly I will have at it again. Thanks for all the help.

 

[hexbasher]

it doesnt matter how "accurate" youre measuring, you only need to measure the DIFFERENCE...and since you used the depth rod on your calipers for the both you should be very close

hummm, the machining on your subplate is different than mine

 

[nevanevan]

Good to know. My press is about 7 years old. I think it was just after they changed the style to the ez-ject system.

 

[slicknova]

OP - Did you end up reading this thread? http://www.ar15.com/forums/t_6_42/349532_Hornady_OAL_issue_fixed_.html

It was a link on the last page of the one suggested by thump_rrr
I think It applies more to OAL....seems to be a issue acknowledged by hornady, BUT they do say the press is designed to be run with the 5 stations being used. Curious, how old is your press?

 

[nevanevan]

I called hornady on Friday of last week. They advised me that the OAL will stabilize when only all 5 stations are occupied with brass. They claimed it was due to shell plate flex.

I tore the subplate off again after receiving the precision shim kit I ordered, My measurment of 0.007" gap allowed me to insert a maximum of .001" shim for it to still work!! That being said, with this shim installed, there is no case movement when cycling the press and it seems to be really smooth.

 

[theDuck]

After seeing the shim 'fix' I gave it a try. I'm glad I saw the picture of measuring the sub plate with it upside down. Makes a difference. Anyway I had a difference of .005" between the hub and sub plate. I put in a .004" shim. That little bit took out the fifth station tilt and made the whole workings solider. It was definitely worth doing for me.
I got the package of Precision Brand Arbor shims from an industrial supply for $16.94. Now I have a bunch of extra shims.

 

[slicknova]

I did the shim kit mod today. Was only able to fit .0025 worth of shim in, Or I would have binding if the shell plate was at just the right spot. This leads me to believe I have a bent shell plate or subplate. Either way, definitely notice a difference in how the press indexes and how "tight" the shell plate is.