Has Anyone Re-Wrapped a DonnyFL FX Moderator to make it Quieter?
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Took the DonnyFL FX moderator apart and found that the internal baffle is fixed to the front end cap and cannot be removed. I might try to find one of the stock empty tubes so we can further this project but for now I’m afraid it is stalled.
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Your call, Mike; but replacing the integral spool/endcap it part of the deal. That is how the Shogun insert works.
That said, certainly, the empty tube variety is more versatile. The designs below may be wider than you are thinking, but are inserts for an empty DFL extender tube. While one looks like it could take a felt wrap, it was not configured for it. The other one has my interpretation of a Tesla valve.
That said, certainly, the empty tube variety is more versatile. The designs below may be wider than you are thinking, but are inserts for an empty DFL extender tube. While one looks like it could take a felt wrap, it was not configured for it. The other one has my interpretation of a Tesla valve.
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Cost for the design/s is zip. I show images and provide STL/s. You can have it/them printed by anyone you like, or do it yourself. If you ask me to recommend someone to print for you, I have two guys that do good work and are not greedy. You would negotiate with them in private. The amount of material and print time will be the main drivers for the cost. At this point, I don't know the outside dimensions of your moderator, so I don't want to guess at the price.
This exercise is experimental with some chance that the results may not impress you. My goal is for you to prefer the sound of the replacement insert. Evidence of that would be that you elect to keep it installed, rather than put the stock parts back in. In addition, grouping ability needs to be better, or the same as stock. Certainly not worse.
If you use a dB meter to help make that decision, you need to take steps to ensure the meter does not clip (max out the reading), because then all inserts will measure the same. Ditto for not having a loud trap/target too close to the meter. It is possible for one muffler to measure a few dB lower than another, but for you to prefer the sound quality or tone of one that measures a few dB higher. Any significant difference will be immediately obvious to your ears.
So, as long as you realize that this is not a developed product that is being offered, but an experiment, your expectations should not be disappointed. If we go back to the beginning; the point is to combine a larger number of conical air strippers with a felt wrap, to see what happens.
This exercise is experimental with some chance that the results may not impress you. My goal is for you to prefer the sound of the replacement insert. Evidence of that would be that you elect to keep it installed, rather than put the stock parts back in. In addition, grouping ability needs to be better, or the same as stock. Certainly not worse.
If you use a dB meter to help make that decision, you need to take steps to ensure the meter does not clip (max out the reading), because then all inserts will measure the same. Ditto for not having a loud trap/target too close to the meter. It is possible for one muffler to measure a few dB lower than another, but for you to prefer the sound quality or tone of one that measures a few dB higher. Any significant difference will be immediately obvious to your ears.
So, as long as you realize that this is not a developed product that is being offered, but an experiment, your expectations should not be disappointed. If we go back to the beginning; the point is to combine a larger number of conical air strippers with a felt wrap, to see what happens.
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For reference, this is Mike Allen's FX DFL moderator version:
donnyfl.net
Based on Mike's question and the discussion above, I did three 3D printable insert design variants for Mike to try out. As no money changed hands, I am making the STLs available to anyone who wants to try them. They are all intended for .25 caliber - or smaller.
Version 1 and 2 are the closest to the FX DFL insert, although the felt wrapping section is a little shorter. This is to enable fitting in the cone that blends the 20 mm OD section into the 31 mm section. That cone is to enable 3D printing with supports off.
Version 3 has more open air space between baffles, with just enough open space around the periphery to take two layers of 1 mm thick felt. The idea is to span the "flats" over the open windows, and tie down the felt with wire ties in the grooves near the ends of the slotted section of the moderator. In other words, Version 3 is not trying to flow much air through the felt. Rather, the felt is intended as a very poorly sprung "trampoline", to reduce pressure wave reflection.
This, while Versions 1 and 2 have a substantial air space between the 20 mm OD section and 31 mm OD section. The idea is to use a "felt" material that is not impervious to air. Not if you stuff that entire space full of material; else you have just reduced the expansion volume of the moderator substantially. A thin layer of closed cell foam that loosely contacts the ID of the metal outer casing would be OK, because it does not take up most of that secondary air space; but acts as a poor pressure wave reflector.
The point of the exercise was to mimic the DFL design, but use more efficient conical air strippers. Version 1 has one more baffle than Version 2. Else they are the same.
See images comparing the three versions below. Version 1, 2 and 3 appear top to bottom.
The thread is sized to accept a 25 mm x 1 mm pitch male thread, straight off the printer. It is suggested that you print just the threaded portion of the part for a trial fit, using the stock endcap; before printing the whole part. You can make (the same) small adjustments to both the X and Y axis calibration in your slicer, to make the thread fit tighter or looser. Leave the Z axis at 100 %, or a pitch error will be induced.
The part and thread diameter dimensions I used are based on a history of PETG prints, produced by AGN members miksatx and TorqueMaster. You are free to print your own parts, or have anyone make prints for you. But if you asked for my recommendation, it would be the above two members.
All three STLs are in the same ZIP file - attached below.
Please note: These parts must be printed vertically, with the threads up. Else the internal cones are not self supporting during printing. Slicer support settings need to be OFF.
1.36 x 5 inches FX/DonnyFL – DonnyFL International
This is a custom size that comes with your FX airguns if you decide to upgrade the suppressor. Same length as the Tanto but slightly larger in diameter, comparable to the FX factory suppressor. This weights around 4.7 ounces. Comes with protective red tube for easy transport and storage.
donnyfl.net Based on Mike's question and the discussion above, I did three 3D printable insert design variants for Mike to try out. As no money changed hands, I am making the STLs available to anyone who wants to try them. They are all intended for .25 caliber - or smaller.
Version 1 and 2 are the closest to the FX DFL insert, although the felt wrapping section is a little shorter. This is to enable fitting in the cone that blends the 20 mm OD section into the 31 mm section. That cone is to enable 3D printing with supports off.
Version 3 has more open air space between baffles, with just enough open space around the periphery to take two layers of 1 mm thick felt. The idea is to span the "flats" over the open windows, and tie down the felt with wire ties in the grooves near the ends of the slotted section of the moderator. In other words, Version 3 is not trying to flow much air through the felt. Rather, the felt is intended as a very poorly sprung "trampoline", to reduce pressure wave reflection.
This, while Versions 1 and 2 have a substantial air space between the 20 mm OD section and 31 mm OD section. The idea is to use a "felt" material that is not impervious to air. Not if you stuff that entire space full of material; else you have just reduced the expansion volume of the moderator substantially. A thin layer of closed cell foam that loosely contacts the ID of the metal outer casing would be OK, because it does not take up most of that secondary air space; but acts as a poor pressure wave reflector.
The point of the exercise was to mimic the DFL design, but use more efficient conical air strippers. Version 1 has one more baffle than Version 2. Else they are the same.
See images comparing the three versions below. Version 1, 2 and 3 appear top to bottom.
The thread is sized to accept a 25 mm x 1 mm pitch male thread, straight off the printer. It is suggested that you print just the threaded portion of the part for a trial fit, using the stock endcap; before printing the whole part. You can make (the same) small adjustments to both the X and Y axis calibration in your slicer, to make the thread fit tighter or looser. Leave the Z axis at 100 %, or a pitch error will be induced.
The part and thread diameter dimensions I used are based on a history of PETG prints, produced by AGN members miksatx and TorqueMaster. You are free to print your own parts, or have anyone make prints for you. But if you asked for my recommendation, it would be the above two members.
All three STLs are in the same ZIP file - attached below.
Please note: These parts must be printed vertically, with the threads up. Else the internal cones are not self supporting during printing. Slicer support settings need to be OFF.
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I added a wrap of Magic Eraser (the thinnest made) to a Tanto.
It quieted things down modestly.
Enough so that I have continued to use it.
And accuracy has not been affected.
FWIW the Magic Eraser worked better in the moderator than it does as a cleaning pad
It quieted things down modestly.
Enough so that I have continued to use it.
And accuracy has not been affected.
FWIW the Magic Eraser worked better in the moderator than it does as a cleaning pad
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I am in discussions with miksatx to print these and I’ll be doing some testing. I’ll report back!
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Version 2 with one of my Tanto end caps screwed down. tight fit the closer you screw to the bottom. had to use some super lube. reprinting a Version1 had to make some changes.
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Someone talked about removing the felt from a donnyfl, and replacing it with cork. I have the cork, but have not tried it yet…
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A Combination of a deep cone baffle + felt wraped curls have been done before, years ago by LANE .. but were he live at that moment moderators were banned.. he discontinued making them and he stay doing regulators and pcp parts.. years ago I had some make me one like the ones he used to make .and my 90fp .22 condor sound like is was damaged..you could actually only here the hammer strike..
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