98 Desert Fox: Main Page Getting Started: Tips for a New Owner    98 Desert Fox Exploded View and Schematic    Classic Fox Exploded View and Schematic Fox Troubleshooting    Troubleshooting: Air Leaks    Troubleshooting: Cycling Problems    Troubleshooting: Ball Breaks Tweaks: Things you can do for your Fox    Regulator Theory and Tuning    Trigger Work and Bolt Polishing    DIY Dial Velocity Adjustor Accessories: Aftermarket Parts for the Desert Fox

Tweaks: Trigger Stoning

Because of the blow-forward design of the mechanism, the Desert Fox has an excellent trigger out of the box. But it is a mass-produced marker and can be improved with some work. You'll need some cylindrical (pin) punches and a block with a hole in it to drive out the pins through the sides of the trigger frame and remove the trigger and sear. The safety must be pushed clear of the trigger frame from the left side (looking at the frame from the top, with the regulator closest to you). The frame contains a tiny spring-loaded ball bearing, so watch out! You'll need it to reassemble the frame.     Once you've got the parts out you will see that they have a dark pebbled finish from the EDM (Electro-Dischage Manufacture, a method of cutting metal with electrodes) and hardening process. Oddly, the parts are almost identical to the trigger and sear from an ICD 'Cat, though that is a totally different bolt mechanism. Use a diamond whetstone to remove the high spots and smooth the action. You only have to worry about contact points: the sides and top of the sear, and the sides of the trigger. Now comes the tricky part.   There are two contact areas that determine the 'feel' of the trigger: The rear upper corner of the sear where the bolt is held and then released, and the contact point between the trigger and sear, (back ledge of the trigger, front tip of the sear) where the sear is held and released. Note the parts are HELD and released, if the parts are altered too much then the trigger becomes unpredictable and unsafe. I recommend that you be conservative and concentrate on making the edges square and smooth and sharp while maintaining the same shape as the original design. In other words, clean them up, but don't change them. Some Automag tuning pages recommend grinding a sideways slope to the top of the sear to reduce the contact point to the high corner. This may be effective, but will also cause the part to wear more quickly. Be careful, and please don't hold it against me if you have to order a replacement trigger or sear.   When you have the trigger and sear squared up and thoroughly cleaned you are ready to look at shimming the trigger. To manufacture thousands of markers at a competitive price ICD must use relatively large parts tolerances, which they overcome with clever designs. The OEM trigger has a little side-to-side slop, and this can be taken up with a thin brass washer inserted on one side of the trigger as the pin is re-assembled. Get some number 6 brass washers from Home Depot and carefully file out the hole in one to slide over the trigger pin. Then use the diamond whetstone to grind the washer thin enough to just slide into one side. How thin? This will vary from gun to gun. You'll have to keep grinding and checking the fit until it's juuuussst riiiiigghht.   Now clean everything with alcohol and re-assemble the trigger frame. Start by installing the trigger and driving the pivot pen through the rear top hole. It's kinda tricky getting it barely through into the trigger slot so that you can locate the shim and trigger in place. Then you'll need about three hands to hold everything in place while you drive the pin the rest of the way through the trigger frame. This is all easier if you happen to have a second pin punch; slide it into the frame hole and use it to assemble and hold everything in alignment, then hammer in the trigger pivot pin to drive out the 'alignment' punch.   Now you can install the safety. Holding the frame in front of you, with the top up and the rear closest to you, start to insert the end with the scalloped ridges into the right side of the frame. depress the trigger to push it through the front trigger hole and stop when you get it just over the ledge on the other side of the trigger frame. Now turn the frame over so that the grip is up and the open (left side, before) safety hole is facing you. Look into the hole and you'll see a small hole at the bottom of the opening. Move the safety until the end is just on the far side of the hole and tilt the grip away from you. Then find the ball bearing that dropped out when you disassembled the safety and drop it in the hole. If gravity is working, it should roll right in. There is a tiny spring in the hole, so you may need to press the bearing down to finish pushing the safety into the other side. You should hear a 'click', and then the safety should work normally.   Next comes the sear. If you removed the back pin to detach the sear spring from the frame, start by driving that pin back in, so it is almost through to the far side of the sear slot, then hook one end of the spring over the pin and finish driving it into the center of the frame. Now hook the other end of the sear spring through the small hole in the bottom tab of the sear and slide it into place. Start driving the sear pin into the trigger frame and stop when it binds against the side of the sear. Now push the sear forward against the sear spring tension until the pin pops through the elongated hole in the middle of the sear. Finish driving the sear pin into the frame, apply some oil to the trigger and sear, and you are done.   Wooooo! You're done!   Obsessive Bonus Activities: Polishing the Trigger Pivot pin and filing the ends off evenly.

Tweaks: Bolt Polishing

The bolt on the Desert Fox has a couple of critical contact points. The sides of the rear flange ride against the inside walls of the aluminum Upper Receiver and should be polished to reduce friction. The flat forward face of the same flange is the contact and release point for the sear.     The Bolt rotates slightly each time the marker is fired. The compression of the spring causes it to twist and it makes the bolt precess as it unweights on the cocking stroke. This means the sear latches onto a new section of bolt each time it catches. So to get the sear to release consistently, the bevel for the face must be consistent all the way around the rear flange. Check it before polishing, and if you need to, lightly file the edge to make the same chamfer around the circumference.   The easiest way I've found to polish the bolt is with the 'Scotchbrite' type plastic steel wool (there's an Oxymoron for ya). This is now available in different grits equivalent again to steel wool, in auto parts stores. I've used the 1, 0, and 0000 grades to gradually work out scratches pretty easily. Take the pad and lay it on the edge of your worktable and then rub the part back and forth over the surface. Damn easy. While you are at it, you may want to look at the ends of the Mainspring and file and polish them as well.   Finally, check the white Delrin Bolt Tip to make sure the surface is clean and unscratched, and that the face that comes into contact with the paintball is smoothly rounded. The lighter grades of Scotchbrite work wonders on the Delrin, but it's soft, so go lightly. The sides of the bolt tip seal against the inner diameter of the firing chamber, so a good fit means less blow-back and better efficiency; don't go too far!

Tweaks: Adjusting the Trigger Limits

ICD provides for screws to set both ends of the trigger range on the Desert Fox. This is something that would require custom mods or a replacement trigger frame on markers like the Autococker and Automag. Nice job, ICD!   The limit screw that sets the distance the trigger moves forward is screwed into the bottom of the upper receiver above the trigger spring, a standard black socket head cap screw. Do this limit first. Note the position of the screw before removing it, then back it out and apply blue, medium strength Loctite to the threads to keep it from moving once you've set the best location. Loctite takes a few minutes to set, so you've got time to work. Screw it back into the upper receiver and advance it a little beyond where it was when you started.   Now comes the trial and error part of the program. Reassemble the marker and gas it up. Squeeze off a few shots with a plugged barrel but no paintballs. Still working fine? OK, de-gas and tear it down again, adjust the screw out a little more, then re-assemble and try it again. What we're looking for is the point where the trigger will not release and catch the sear for the next shot. You'll know it when the a second pull on the trigger does not fire, or the marker fires erratically. Now take the thing apart again and turn the screw back IN 1/4 to 1/2 a turn, then test again. The trigger should work reliably, but the trigger stops moving forward at the shortest point possible.   The rear stop adjustment is much easier. Now we're adjusting the setscrew in front of the trigger, which should be accessible with an allen wrench from outside the gun. Again, remove the screw and apply medium Loctite so your adjustments will stay where you want them. With the marker gassed up as before, shoot a few cycles, then adjust the screw in. Repeat. Repeat. Repeat. When the gun will not fire reliably, back off the screw 1/2 a turn and test the trigger a few rounds. Now the trigger should stop moving just after the sear releases and marker fires, and your trigger movement is minimized.   Note: Some folks have written and are missing this screw. Look at the bottom of the trigger frame, in front of the trigger, between the two large frame screws that hold the upper and lower receiver together. There should be a small setscrew there. If all you see is a small threaded hole, then the screw is missing. No big deal, just go down to the hardware store and buy a 1/4 inch long 8-32 setscrew to insert in the hole. It will probably be around 35 cents. Then follow the directions above to set the rear limit. My 'Fox came without the screw, but I chalked it up to Skanline.   You've now finished the trigger job on your Desert Fox. It should feel smoother, lighter, and faster.

Disclaimer:   The Desert Fox is not a difficult marker to work on, but there is some chance that things could go wrong. If you are uncomfortable about working on the regulator or trigger of your marker, Don't Do It! These tips assume some mechanical aptitude and use of the correct tools. If you mess something up, you'll have to replace it.   Indian Creek Designs has an excellent warranty, and they stand behind their guns. If you have a problem and ship it to them, they promise 24 hour turnaround on repairs. There are many testimonials on the web to back this up. They will also do upgrades based on production improvements.   ICD wants me to make it clear that this is not an official ICD site. Any changes you make to a marker under warranty may void that coverage. Don't blame them, don't blame me. There, that should cover it.   the ICD Official Corporate Website   Finally, Don't use an unsafe marker, and Be Careful with CO2 and Paintballs. Paintball markers are not toys, so be an adult and take responsibility for your own actions...

Links: 'Fox info on this Site

98 Desert Fox: Main Page Getting Started: Tips for a New Owner    98 Desert Fox Exploded View and Schematic    Classic Fox Exploded View and Schematic Fox Troubleshooting    Troubleshooting: Air Leaks    Troubleshooting: Cycling Problems    Troubleshooting: Ball Breaks Tweaks: Things you can do for your Fox    Regulator Theory and Tuning    Trigger Work and Bolt Polishing    DIY Dial Velocity Adjustor Accessories: Aftermarket Parts for the Desert Fox   ICD 'Cats ICD Barrels: Aftermarket Barrel Review Basic Airsmithing Links to ICD Resources on the Web

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