Metal type for shotgun magazine tube extension

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hammermill
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Joined: Sun Jun 27, 2010 10:43 pm
Location: pendleton or

Re: Metal type for shotgun magazine tube extension

Post by hammermill » Tue May 29, 2012 11:08 pm

i hope this helps blindhog has offered help many time

parkerizing tutorial

http://www.blindhogg.com/parkerizing.html

heed the advice about the kitchen

Harold_V
Posts: 17080
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Metal type for shotgun magazine tube extension

Post by Harold_V » Tue May 29, 2012 11:45 pm

The method I use is accomplished with the old style knurling tool, not the scissor type. I can't address that one, as I've never used one.

Any diameter can be knurled successfully, assuming you're knurling a diamond pattern. The knurling tool permits the knurls to wander side to side, compensating for irregular diameters.

Oil the part and knurling tool well while knurling.

Once you have established the proper knurl, it is highly unlikely to split, assuming you keep the rolls deep enough in the part.

There's two different knurling types. One is when the knurl starts at the end of a part, the other when you knurl a specific area on a shaft, without starting at an end.

For the first example, where you start from the end, set your knurling tool so the rolls are dead parallel with the part, as you will knurl in both directions. Set your feed rate so you're feeding at least .010" per revolution. More is acceptable. Start the spindle at a reduced speed, well below machining speeds (varies with the diameter). Move the leading edge of the knurling tool over the part by about 1/16". Quickly plunge the tool in to the part, so that you get a deep knurl. Stop the spindle and examine to see if the knurl has split or not. It usually does not. Once you have established the knurl you desire, back off the cross slide a little, but keeping the rolls engaged with the knurl that was just created. Engage feed and allow the tool to run to the opposite end of the desired knurl. When you get there, feed deeper, and reverse feed, or reverse the spindle. Repeat until you are satisfied with the depth.

If the knurl splits, chamfer or (completely) turn off the bad knurl and try again. Do not leave any of the bad knurl, for that will (mis-)time the rolls once again.

To start a knurl in a prescribed area, without having an edge at your disposal, repeat the above, then when you have the piece marked (pencil marks can define the area you desire to knurl), start the spindle at a slow speed, and quickly plunge the knurling tool deep in to the part, all the while quickly moving the carriage to the side. Stop the spindle to see if you have achieved the desired pattern. If so, engage power feed and run side to side, deepening the knurl to the desired depth. If the pattern splits, move to a new area and repeat the process. Once you have established the desired knurl, and of adequate depth, you can knurl over the bad portion and correct the pattern. If you aren't deep enough with the rolls, that may not happen, so ensure that you are knurling at a respectable depth when trying to correct a bad knurl.

When starting from an end, it's not uncommon for the end to be somewhat deformed. If you hope to have a square corner, allow material to face the part afterwards, of if a chamfer is acceptable, you can usually chamfer the edge and remove the deformed area.

Luck! Trust me, this method works. :wink:

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.

Harold_V
Posts: 17080
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Metal type for shotgun magazine tube extension

Post by Harold_V » Tue May 29, 2012 11:46 pm

hammermill wrote:i hope this helps
Thanks, hammer. Copied and saved.

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.

737mechanic
Posts: 349
Joined: Thu Jun 04, 2009 6:27 pm
Location: Dallas

Re: Metal type for shotgun magazine tube extension

Post by 737mechanic » Wed May 30, 2012 3:07 pm

hammermill Thanks for that link. I just ordered some manganese phosphate and figured I will do it myself as I am sure there will be plenty of other stuff I will want to parkerize.

Harold_V Thanks for the info I am going to try that next time. Sounds like it would work more consistently than what I am doing.

737mechanic
Posts: 349
Joined: Thu Jun 04, 2009 6:27 pm
Location: Dallas

Re: Metal type for shotgun magazine tube extension

Post by 737mechanic » Mon Jun 04, 2012 1:44 pm

Here is the finsihed product. Turned out great. The parkerizing is really easy and looks good.
Attachments
DSCN2691.jpg
DSCN2698.jpg
DSCN2696.jpg
DSCN2695.jpg

Harold_V
Posts: 17080
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Metal type for shotgun magazine tube extension

Post by Harold_V » Mon Jun 04, 2012 2:53 pm

I gotta say, that sucker turned out really well.

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.

hammermill
Posts: 2938
Joined: Sun Jun 27, 2010 10:43 pm
Location: pendleton or

Re: Metal type for shotgun magazine tube extension

Post by hammermill » Mon Jun 04, 2012 3:07 pm

so you gained 2 rounds in capicity?? did you have to change the spring?? looked nice when as was said and done.

737mechanic
Posts: 349
Joined: Thu Jun 04, 2009 6:27 pm
Location: Dallas

Re: Metal type for shotgun magazine tube extension

Post by 737mechanic » Mon Jun 04, 2012 5:09 pm

Thanks guys, I am really happy with it.

hammermill I gained 2 rounds and yes I had to put a wolff spring in it because the factory spring was too short.

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