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jlpollard · New Member

Has anyone ever tried using a truck bed type coating on their spring in a break barrel?
My Mendez is pretty loud and I was going to coat it in tar.
That got me thinking, usually a bad thing Cool

, the stuff you can put in your truck bed is a rubberized coating.
If you used that on the spring, how much FPS would you loose, or are there any other adverse problems anyone see?

Jim

Slavia · Moderator

I wouldn't do it for several reasons: First, it isn't rubbery. Truck bed liner is more of a plastic, and is stiff enough to probably flake off as the spring flexes. Second, it goes on thick enough to change the tolerances with the spring guides, which is an invitation to scrape off the spring. Third, the non-skid property is because it has grit in the mix, which would be like throwing sand in the innards of your gun. The same would apply to rubberized undercoating, minus the grit part.

You would be better off with thrust washers, fitted spring guides, and a buttoned piston. When they talk about putting "tar" on the spring, they're really talking about a tar/grease mix that sticks but retains lubricity. Try several samples of grease - put a dab between your thumb and index finger. As you pull your fingers apart a light grease just separates, while a stickier grease will form threads as the fingers move apart. That's the kind of thing they mean when they say "tar." Still grease, but thick and sticky.

jlpollard · New Member

I guess that makes sense.
I could get around the abrasive part but you're right about not being flexible enough.
O well...can't blame me for trying Laughing

radar · Silver Status Member

You might get away with mixing your own out of the real rubberized undercoating and some non-hardening grease to thin it. Never tried it. It might work. I just use Jim's tar from Air Rifle Headquarters.

AirGunEric · Site Admin

I have never liked the concept of a "tar" in an airgun to cut down on noise and believe Slavia has the right idea- if the noise is a big problem, spend the time and do things properly- guides and spacers.

radar · Silver Status Member

Chevota · Guest

The way to do it is to use Plasti-Dip, the problem is lube gets under it and separates it from the spring. Another prob is it can cause coil bind if too much is between the coils. I tried it once and it was quieter than tar and without the power loss, but it came off as I mentioned. I do however have a possible fix that I haven't tried yet, so if you want to experiment let me know and I'll tell you what it is.

AirGunEric · Site Admin

Why not post your "experiment" online- asking for people to contact you specifically on the issue defeats the point of an online forum for everyone to see things and perhaps learn something.

robert w · Senior Member

i have used plastidip and it will flake off screwdrivers so I wont put that stuff on a spring

garththomas · Veteran Member

Have you looked into putting a sleeve inside the piston as per a poor mans delrin spring guide. I have done this in both my QB57 Chinese air rifles and it has greatly reduced the noise, the price was right I used a plastic bottle and cut it the inside diameter of the piston so the edges butted, I cut it the length and cut out the cocking slot after it was in place.

Just to add I have used these for thousands of shots and they've held up really well. This is where I got it. http://www.gatewaytoairguns.org/GTA/index.php/topic,8330.msg68150.html#msg68150

garththomas · Veteran Member

I was looking at a schematic for that rifle and if you noticed a lot of slop of the spring inside that piston the I think a sleeve is worth a try, between the piston and the spring not the guide with the cocking notch. Also a different spring guide with a tighter fit could help. Better than gumming up the insides, JMO.

Slavia · Moderator

I'll assume that when jlpollard said "Mendez" he meant Mendoza. My Crosman/Mendoza RM577 had a lot of slop in the fit of the internal parts, so garththomas's sleeve suggestion might fit nicely. With the spring flexing for every shot I would be apprehensive about applying any coating that could flake off.

Amigo · Veteran Member

The only coating I use on my piston springs is "Red & Tacky", a Lucas Oil NGL 2 grease. It is very tacky as per Eric's described definition.
I apply it in a thin film to thoroughly coat all aspects of the wire.

As a side note, it also works well on lathe gears out-board of the head-stock gear case as it clings well during gear rotation.

I agree that well fitting spring guides are the best noise reduction fix and properly fitting guides will likely prolong spring life.

robert w · Senior Member

amigo, that lucas is very sticky isn't it? I never thought about using lucas grease. but after you said that I will get a tube out of the shop. another sticky grease is john deere corn head grease . I got some on my hands and it was 'ell to get off . I was out of tar and used some of the john deere grease and it stayed put very nicely

Mentolio · Veteran Member

So what kind of materials do you guys recommend using for a "spring sleeve?" Also, how tight do you want the clearance between the sleeve and the spring?