24 replies to this topic

[481IceDragon]

A friend of mine went to paint his Nitefinder and lost his plunger head and o ring. I'm wondering if there's anyone who knows of a good material to completely replace the plunger head and o ring. Thanks for any help.

Edited by 481IceDragon, 26 February 2013 - 11:17 PM.

[KoRnEd]

It would probably be easiest to buy another one.

[DartSlinger]

Yes, but we also hope to improve the seal as his is couplered as coops (sic) tutorial shows (youtube) (sic) and he wants to upgrade the seal and spring.

Something like a rubber washer and a polycarbonate circle would probably work. Just go to the hardware store and see what fits. A rubber washer that has an O.D. slightly larger than I.D. of the plunger tube would create an excellent seal, and just screw it onto the plunger with a screw and a polycarbonate circle or metal washer.
If you are really looking to improve performance, you should consider putting a homemade plunger into it.

Edited by DartSlinger, 27 February 2013 - 12:39 AM.

[481IceDragon]

It would probably be easiest to buy another one.

Yes, but we also hope to improve the seal as his is couplered as coops tutorial shows (youtube) and he wants to upgrade the seal and spring.

[MAV13]

Newer nitefinders have a tapered plunger tube. This means that any replacement head that seals properly at the plunger tube opening will be too tight at the end. That said, you can get a good-enough moving on to perfect seal using the stock plunger head with silicone grease and some teflon tape.

Edited by MAV13, 27 February 2013 - 12:34 AM.

[DICE134]

See if you can find small metal washers that fit in the NF plunger tube, glue a piece of PVC in the ,middle that has a smaller OD(basicly make a sandwich),fill the "sandwich" with epoxy putty, put o-rings around the PVC piece, drill a hole through the "sandwich", and then screw it on to your plunger rod.

Edited by DICE134, 27 February 2013 - 07:26 AM.

[spencerak]

I have used a 1" rubber washer sandwiched between 2 7/8" washers and that has worked pretty well. That is until my spring broke my plunger rod, the poorly taped hole got stripped and the head came off.

[481IceDragon]

See if you can find small metal washers that fit in the NF plunger tube, glue a piece of PVC in the ,middle that has a smaller OD(basicly make a sandwich),fill the "sandwich" with epoxy putty, put o-rings around the PVC piece, drill a hole through the "sandwich", and then screw it on to your plunger rod.

I have used a 1" rubber washer sandwiched between 2 7/8" washers and that has worked pretty well. That is until my spring broke my plunger rod, the poorly taped hole got stripped and the head came off.

Thanks guys, I'll make sure to experiment with both.

[T da B]

The "washer sandwich" is nice because it is cheap, easy, and takes up very little overall length. Make sure to make your fender washer on top as small as possible--this will prevent the creation of a vacuum between the dart and plunger head if you load before you prime. In addition, make your lower fender washer as big as possible in order to prevent open-ended springs from hooking over the rubber washer and also to allow the rubber washer to seal well on the forward stroke. My plunger heads are usually as follows (from top to bottom): 6-32 bolt, #6 washer (metal or neoprene), small fender washer, neoprene washer, biggest possible fender washer.

P.S. If your open-ended spring keeps hooking over the neoprene washer, you may need to add a "spring spacer," which is a piece of something that fits over the plunger rod and under the spring to keep it centered near the plunger head.

[sublimedom777]

#13 O rings available in the Plumbing repair section of Home Depot is a good replacement/upgrade for NFs.

That is all.

[Samurai kidd]

Newer nitefinders have a tapered plunger tube. This means that any replacement head that seals properly at the plunger tube opening will be too tight at the end.

This isn't quite true of replaced plunger heads. Because rubber washers and skirt seals ares so flexible, they can actually be wider than the PT and still have a low coefficient of friction, even lower than the original plunger head with seal improvements.

[quertyman]

One word, Bathtub plugs. They are my new favorite PH and can be made to fit in any plunger size. I can do this by
1. getting different sizes
2. tightening fender washers around it to expand it to the plunger size
3. sand it down on my drill press to make it fit perfectly.
+ The thick rubber nature of it lets you use it as a "padding" for the plunger tube.
+ They are set at a ok price (around 2.30$ each)
+ They are widely available.

For these reasons I think they should become a new standard instead of expensive skirt seals.

Edited by quertyman, 27 February 2013 - 11:11 PM.

[MAV13]

One word, Bathtub plugs. They are my new favorite PH and can be made to fit in any plunger size. I can do this by
1. getting different sizes
2. tightening fender washers around it to expand it to the plunger size
3. sand it down on my drill press to make it fit perfectly.
+ The thick rubber nature of it lets you use it as a "padding" for the plunger tube.
+ They are set at a ok price (around 2.30$ each)
+ They are widely available.

For these reasons I think they should become a new standard instead of expensive skirt seals.

This. If you don't want to just replace it with a new stock head, which is the most reliable option.

[481IceDragon]

This. If you don't want to just replace it with a new stock head, which is the most reliable option.

I don't plan on buying a new nitefinder for one part. I need to replace the whole plunder head and cap. I think I'll try each of these ways, combined with some heavy amounts of lithium grease. Thanks for the help guys.

[thedom21]

Just buy a rubber grommet and a nylon spacer with two metal washers, perfect seal every time as long as you know how to use a screwdriver.

[481IceDragon]

Just buy a rubber grommet and a nylon spacer with two metal washers, perfect seal every time as long as you know how to use a screwdriver.

Would I just need to buy a grommet the same diameter as the NF plunger tube?

[DartSlinger]

Would I just need to buy a grommet the same diameter as the NF plunger tube?

That's obvious isn't it? You can't insert a grommet into a hole smaller than the grommet. Just go to the hardware store and test fit the grommets.

Edited by DartSlinger, 28 February 2013 - 10:59 PM.

[481IceDragon]

That's obvious isn't it? You can't insert a grommet into a hole smaller than the grommet. Just go to the hardware store and test fit the grommets.

No, to someone with no experience with these grommets, or homemade parts, it's not obvious. When he said perfect seal every time, that kind of sounds like 1 size fits all, "as long as you know how to use a screwdriver"

I wouldn't have asked if I knew the answer.

[DartSlinger]

No, to someone with no experience with these grommets, or homemade parts, it's not obvious.

The only way you get this experience is by going to the hardware store and trying the different possibilities, and, therefore, seeing what works. No one on any forum can give you experience: that can only be acquired by you. All we can do is give you advice on what worked for us.

[481IceDragon]

The only way you get this experience is by going to the hardware store and trying the different possibilities, and, therefore, seeing what works. No one on any forum can give you experience: that can only be acquired by you. All we can do is give you advice on what worked for us.

I wasn't asking for experience. i was asking for more information. I was trying to find out more about that method of creating a seal before I went and bought parts, and the nearest town is 25 minutes away, so it's not practical to go to a store to try and figure something out, when half the kids that work at our menards are under 18 and don't know the difference between anything beyond basic hardware, and therefore are of no helpfulness.

[thedom21]

It's going to be a tight fit in the inside of the plunger tube but rolling it along some fine grit sandpaper with some pressure should fix that. Just bring your plunger tube to the store and find one that fits nicely or is just little to tight.

[Samurai kidd]

I found a sort of red rubber washer in my basement. It's about 1/8" thick and shaped like a fender washer (Small hole, wide body), with a very slight cup. It fits perfectly inside of a nitefinder plunger tube.

Anybody know from my description what these are called? I'll get a picture when I find my camera.

[DartSlinger]

I found a sort of red rubber washer in my basement. It's about 1/8" thick and shaped like a fender washer (Small hole, wide body), with a very slight cup. It fits perfectly inside of a nitefinder plunger tube.

Anybody know from my description what these are called? I'll get a picture when I find my camera.

It's just a rubber fender washer that was probably used due to the shape distortion.

[Samurai kidd]

It's just a rubber fender washer that was probably used due to the shape distortion.

I'm convinced it's different. It's much thicker and the rubber feels softer.

[DartSlinger]

I'm convinced it's different. It's much thicker and the rubber feels softer.

Fender washers can come with virtually any thickness or durometer.