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Cut-down OEM spring guide as top hat?
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Author:  cbf123 [ Mon Jun 20, 2016 10:48 am ]
Post subject:  Cut-down OEM spring guide as top hat?

I asked this as a throwaway question in a different thread, but I thought it might deserve its own thread.

I'm going to rebuild the powerplant of my HW98. Stock it comes with what appears to be a Delrin spring guide but no tophat. Do you think it'd be worth using a cut-down OEM spring guide as a top hat (to help keep the spring straight)? Or does the top hat need to be a tighter fit on the spring?

Author:  Chevota [ Mon Jun 20, 2016 1:31 pm ]
Post subject:  Re: Cut-down OEM spring guide as top hat?

I don't see why not. What I do is make a plastic liner for the piston, which is basically like the oem metal one but it fits inside the metal one for a better fit. It acts as a guide but I do it for the noise reduction which it's very good at. If interested I can go into detail on how to make them.
Might as well button it while you're in there. This gun doesn't really need buttons like other guns do, but it still helps. What is does need for sure is grease on the cocking shoe, which imo should reapplied often. Also check to be sure the leading edge of the shoe is burr free and maybe put a slight bevel on it to help it surf over the grease rather than scrape the grease away. The reason is because it takes the brunt of the angular force of the linkage, which should make sense by looking at it when the barrel is ~90 degrees.

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Author:  cbf123 [ Mon Jun 20, 2016 4:06 pm ]
Post subject:  Re: Cut-down OEM spring guide as top hat?

Chevota wrote:
I don't see why not. What I do is make a plastic liner for the piston, which is basically like the oem metal one but it fits inside the metal one for a better fit. It acts as a guide but I do it for the noise reduction which it's very good at. If interested I can go into detail on how to make them.


Info would be appreciated. I've read about them before...what do you use for material? I've seen people suggest pop bottles, then other people who poo-poo that and insist on PTFE sheet. :)

Got any good links on buttoning? Thought about it, but haven't decided if I want to deal with the hassle.

Author:  Chevota [ Mon Jun 20, 2016 8:48 pm ]
Post subject:  Re: Cut-down OEM spring guide as top hat?

The liner I make from 2-liter bottles and it works perfectly. Some things to think about are thickness, size, cost, is it sandable, and misc other issues. For example the fit should be perfect (imo), so you'll likely screw up the first one or more. Or if you're not into that you could make it fit poorly which should still work, maybe. The thickness may need to be .030" or more so one sheet of .030 might be too hard to work but two .015 works great. 2-liter bottles vary but ~.015 +-.003 is the norm. You can try other kinds of bottles too, including white or translucent ones for whatever product as long as it's flat.
I do have some little teflon sheets (~30-50mm?) that are .0075" and .010" thick that I use for piston buttons. I think it's just some very tough plastic with some teflon in it, but the reason I use it is it's super tough and a good thickness for buttons. Plastic from retail blister pkgs is pretty frikkin tough too but usually a little thicker so it means you have to sand them down more, if needed and it usually is. If uninterested in sanding then maybe get one of those super thin collapse in your hand water bottles which are ~.003". Buttons are easy to make and install imo, the liner is much more work but I think well worth it.
Ideally you should email me at chevota at hotmail and I'll send you a complete tuning info pkg. It's about 100 pix so too much for here, but I can post just the liner and button pix if you want.

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