PDA

View Full Version : Timing? Best diameter for front rod..


DriftPunch
June 18, 2002, 07:26
I'll be using the 2 rod method. What do you use for the front rod that goes through the handguard retainer screw? I want a dowel or a brass rod of some type. I measure the screw at about .2 inches, and I doubt that that's a standard size anwhere. Do you pick the next smallest size, and shim it with toothpicks or something?

hockeyfan_019
June 18, 2002, 08:28
I seem to remember that I used 3/16 drill rod last time and it worked great as-is. Someone else suggested automotive brake line since they're a tad stiffer (less sag) but either should do nicely. Make sure each rod is about 3' long though, so you have an adequate length to ensure that they are parallel... HTH

Fred
June 18, 2002, 09:24
I use a pair of 3ft long 3/16" rods from the local Home Depot. However, I find that you need to use some rubber bands to hold all in place especially for the one going through the gas block. The droop is not a big problem if both rods are the same length as the doops will match. Been doing it this way for a while now and find no problems. One of these days I will take the effort to make a tighter fitting sleeve for the front sight so I can delete the rubber bands.

sportsnut
June 18, 2002, 10:41
3/16" rods from Home Depot. Never needed a rubber band. Mark the middle of the rod with a permanent marker and you are ready to go.

DriftPunch
June 18, 2002, 11:41
Cool! Thanks!

Uncle Buck
June 18, 2002, 12:33
Just balance the rod in the hole. If you wedge it in or band it, it may not read true. Also make sure that the hole in the gas block is clean and free of burrs. I use 1/8 inch TIG/OA welding fill rods. It doesn't matter if they droop as long as they droop equally. You can check them for straightness by balancing them on the same flat surface and sighting down the center. The closer the two rods are together in the optical plane, the more accurately you can judge how parallel they are. Always double check by bore sighting. Put the lower on, cradle the rifle on the bench or table and use a mirror to sight down the bore and then check the sights to see if it agrees horizontally with the bore axis.

Steve D
June 18, 2002, 13:24
I got a drill rod from McMaster Carr for $2.47 part number 88645K35 that was .204" in dia for my imbel kit I took gauge pins and measured the largest size that I could fit in the gas block that way you do not have to balance the rod. Measure you hole dia and to be sure the size you need. HTH

goose
June 18, 2002, 14:44
Pardon my ignorance, but what is a drill rod. What are they used for?

Steve D
June 18, 2002, 14:55
I do not know what the story is behind the name but drill rod is a generic term used to descibe steel rods that have a fairly tight tolerance there are many different grades of drill rods they can be hardend with air or oil depending on the compostion. Theycan be fine grain coarse grain high carbob etc.. depending on the application. I chose the cheapest Grade 0-1 because I did not care how hard it got when you heat treat it. HTH

Fred
June 18, 2002, 16:48
While I agree that one does not have to use rubber bands I find that it works better. I also have marked the center to get the rods placed right the first time. The rubber band solution just allows the rods to settle down faster than without. However, if you have all the time in the world be my guest and leave off the bands. I have yet to put together a FAL that pulled to one side because of not being timed correctly.

7.62FMJ
June 18, 2002, 23:26
I use an AR15 cleaning rod assembly through the hole in the barrel and a .30 cal cleaning rod on the rear of the reciever. Remember also to use your bolt with its rat-tail to hold the rear cleaning rod in place. :p