Wednesday, November 23, 2011

Improved Seal Technique

I've been doing light mods on Nerf Blasters for awhile now, but one of the performance upgrades that I've always had trouble with was improving the seal around the O Ring.  I've tried different types of Tapes, but the problem I run into is getting the right thickness around the plunger tube.  When I was working on sealing up electrical bits on a Laser Tag blaster, I brought out my Liquid E Tape (it paints on with a brush and dries in about 4 minutes) and had an idea.  Since the Liquid Tape can be applied evenly in coats, I thought I could make a good seal around the O Ring with it.  After testing it on a few blasters and figuring out how thick to get it, I've pretty much worked out the kinks in this idea.  

Liquid Tape can be purchased at most retailers and hardware stores.  Mine is "Performix" brand that I picked up at Wal-Mart.  They run a little over 4 bucks a bottle and underneath the cap is the paintbrush applicator.  It goes on pretty well.  All you have to do is remove your O Ring and apply it evenly around the end of the plunger tube.  Get the first coat as even as you can (if you can still see orange, it's too thin).  It'll take forever to dry if you use too much though, so don't put this on in gobs.  After 4 minutes, apply a second coat to finish it up.  The bottle says to let it dry for 4 hours for a permanent set.  After that, put your O Ring back on and add a little bit of silicone grease.  This should be a near-perfect seal for Reverse Plungered blasters.  It may require different thicknesses on other types of blasters.  

Liquid Electrical Tape can be removed relatively easily, so if you find you've applied too much, you can get it off after it has dried.  Don't try to take it off while it's still wet.  It makes an awful mess.  The one you see in the pictures was for my Longstrike Blur.  While the Stock Spring that I tried it out on was too weak for this perfect seal, the Orange Mod Works Stage 1 Kit for the Longstrike pushed through it just fine (and is quite powerful too!)  This version had 3 coats on it.  I'll be experimenting more with this Liquid Tape and if I find any other good uses for blaster modifications, I'll post 'em up here.


  1. How much difference have you noticed in range and accuracy? I've got a nerf crossbow that might benefit from this discovery. It's been modded to fire tag darts, and it gets great ranges though I had noticed the plunger seal is pretty poor.

  2. @ Skurj, Range seems consistently better compared to a blaster with just it's AR out. Accuracy really comes down to the dart, and the blasters I've been working with for this fire Streamlines... so it's hit or miss. I haven't done any measured range tests, but preliminary testing shows enough of a performance boost for me to bother posting about it.

  3. Nice. If I do it I'll let you know how it turns out.

  4. On a side note, you really are a pioneer in your field. Up there with Stefan Mohr and whoever put the first brass barrel in a nerf gun, IMO.