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DENNIS MIN 03-13-2010 13:31:42 71.48.125.180 262133 Report to Moderator	forgot to add message... [Reply]   [No Email]
PJH 03-13-2010 18:55:12 71.171.215.99 262152 Report to Moderator	Re: Long post on level controls in reply to DENNIS MIN, 03-13-2010 13:31:42   Dennis, I saw your questions on the previous post. I'll try to comment on the level knobs and adjustments, altho I've never used that exact instrument. The knurled part around the eyepiece will adjust the focus of the crosshairs. You set it to your eyes and shouldn't have to fiddle with it any more, unless it gets bumped or someone else uses it. The knob on the right side of the barrel should be the focus adjustment. You'll likely use it on every shot. The four capstan screws located axially around the barrel are the crosshair screws. I recommend you don't mess with them. In 35 years of using surveying instruments, I've never seen the need to fool with them. The knob directly below the eyepiece and pointing in toward the center of the instrument is the motion lock knob. Loosen it to the left to make large changes in the direction you want to look. Lock it back down when you get close, and then use the slow motion knob right beside it to zero in on the rod. The four knobs near the bottom are the leveling screws. When you turn them, one must extend while the other shortens. Turn the barrel of the instrument so the level bubble is over two of the leveling screws and level it in that direction. Then turn the barrel and do the same with the other two leveling screws. Probably will have to do this again both directions for good level. The leveling screws should never be forced, but must be snug. Forcing them could warp the base plate, and too loose will allow the top to "flop". A little tip - as you level the instrument, the bubble will move the same direction as your left thumb. It looks like there might be a degree plate right below the barrel yoke, and if there is, there should be a plumb bob hook dangling from the underside, seen after you unscrew the instrument from the storage base. A surveyors level is most accurate if you take balanced shots. ie - set the level in the center of the work area. To check the bubble accuracy, simply level the instrument and rotate it to various positions - it should remain level anywhere you turn it, but the round nuts at the ends of the level vial may be turned if adjustment is needed. They are lock nuts, and usually a tool that looks like a small pin is inserted in holes in the sides of the nuts. I've used a small nail - the tool is easy to lose. Also - some instruments have a tiny protective sliding cover over the eyepiece. A tiny pin slides the cover open. I don't think this particular instrument has that feature, but it may. Several people over the years have thought they bought defective instruments because the cover was closed and the sight tube was therefore "dark". Also - the crosshairs can be thrown out of focus so much that it appears they are "gone". You'll see this a lot at auctions - I guess someone wanting other prospective buyers to think the instrument is defective? There I go again assuming the worst. . . I'm thinking you have already figured out most everything about it - sorry for the long post - hope it helps. Paul   [Reply]   [No Email]
dennis min 03-13-2010 20:01:25 71.48.125.180 262158 Report to Moderator	Re: Long post on level controls in reply to PJH, 03-13-2010 18:55:12   PJH, Thanks for the outstanding reply and information! I tried to find anything out about this, and the info was scant. I was curious about the reticle-adjustment though. If the reticles were messed with, I was wondering if it"s worth my time to "adjust" these screws. I was also wondering what the other 4 screws were. I kind of thought there were some gun-scope folks that maybe had performed this adjustment and could advise me about it (or against it). I got kind of intimidated when I saw all the math and trig involved in surveying, which is where I got most of my info from. Geez, those folks know their stuff! I did not pay much for this instrument, and plan on keeping it for my own use like setting landscaping block, setting concrete forms, mostly low-precision elevation-type work. Again, thanks. D.   [Reply]   [No Email]
PJH 03-13-2010 21:14:47 71.171.215.99 262161 Report to Moderator	Re: another dreadfully long post on level controls in reply to dennis min, 03-13-2010 20:01:25   Dennis, I'm not sure what you're refering to as the reticle screws? If they are the four capstan style screws around the barrel of the scope - again, I wouldn't mess with them. If your crosshairs are broken (something I've only seen once in 100's of instruments) you will probably need to send it off for repair. Make sure they aren't simply out of focus. They can be completely invisible if the crosshair focus control is turned to the extremes. That focus control is around the eyepiece, or the reticle as some folks call it. Your eyebrow will touch the crosshair focus control as you look thru the eyepiece. I've never used that particular model of instrument, but they are all pretty similar. Level math is pretty straightforward. Everything is worked off of the heighth of instrument, or HI. Suppose you took a rod reading on the flowline of the upstream end of a pipe culvert and read 5.0 on the rod. A shot of 5.5 on the flowline at the downstream end would indicate 0.5 feet of fall in that run of pipe. If you were to assign an elevation of 100.0 to that same upstream flowline, then the HI would be 105.0. Subtract the 5.5 reading at the downstream end and you would have 99.5 for an assumed elevation. You could shoot anything within range and subtract the reading from your HI of 105.0 to establish a relationship. If you're working in hilly terrain, it gets mildly complicated. Your rod will be too short, or you'll be looking into the ground below the rod. Then you've got to learn how to make a "turn". It basicly involves establishing an elevation on a solid object, such as the downstream flowline of the pipe I mentioned earlier. You know the flowline of the DS end is 99.5. Pick up the instrument and re-set it for convenient readings, take a new shot on the DS flowline (say 12.5) and add 12.5 to the known elevation of 99.5 - your new HI is 112.0. Now you subtract every shot at your new set-up from the HI of 112.0. You can carry an elevation for miles using this method, but if it's critical work, you must make a complete "loop" back to the original or another known elevation to prove your accuracy. Otherwise you are "open ended", and may be working off of a busted shot or math error. You should be able to complete your loop within a couple hundredths of a foot, depending on what level of accuracy you're needing, of course. A tip: On "turns", add your backsight readings and subtract your foresight readings. And remember to keep your shots balanced. Your rodman should take the same number of steps walking to you as he takes walking on past you. More boring info that you probably already knew :-) Paul   [Reply]   [No Email]
dennis min 03-13-2010 21:28:01 71.48.125.180 262162 Report to Moderator	thanks in reply to PJH, 03-13-2010 21:14:47   PJH, Don"t go selling yourself short. I pretty much understood what you"ve written, at least enough for me to get outside tomorrow and try a few elevations, both open and closed, just to see. Did you happen to see the vernier scale picture? I am still trying to figure that one out. 60 minutes per degree, but I am struggling how to add/subtract the minutes from the degrees. Perhaps it"s too far past my bedtime for heavy thinking. Again, I appreciate your help. D.   [Reply]   [No Email]
dennis min 03-13-2010 20:23:22 71.48.125.180 262160 Report to Moderator	Hopefully a few more photos in reply to dennis min, 03-13-2010 20:01:25   PJH, Perhaps a few more questions for you, if you don't mind. 1. Is the small hole in the bottom whre the plumb bob gets hooked to? 2. The degree wheel is measured one degree increments, how do I read the 30-60-30 vernier? I assume it's in minutes?   [Reply]   [No Email]
PJH 03-13-2010 22:07:35 71.171.215.99 262165 Report to Moderator	Re: Hopefully a few more photos in reply to dennis min, 03-13-2010 20:23:22   Dennis, there's usually a small open wire hook hanging fron the center of the base. If you plan to use the angle feature, you'll probably want to see if you can re-fashion one there. You should also check your leg set. Some have the hook or even a wire loop attached to the center of the tripod legs. Yours may be that type. On the degree scale - that is considered a 30 minute vernier, and it's unusual to what I'm used to. I would consider the number 60 to be zero. With that thought in mind, your angle reading would be 0 degrees, 25 minutes right of zero. The 60 line is about midway between the zero and the one degree lines, and the first tic left of the right 30 would be the 25. As I ponder that scale, I am puzzled how one would set an angle of say 0 degrees 50 minutes. I think you would line the left 20 on the upper scale with the left 3 degree line on the circular scale. The 30 right plus the 20 left should put you at a total of 0 degrees 50 minutes right of zero. The main thing to be aware of is the location of the vernier center with the degree circle. If you're somewhere between 0 degrees and 1 degree, your vernier will finish the story for you. If it's 3/4 of the way to 1 degree, then obviously you'd look for a reading around 0 degrees, 45 minutes. Your instrument may also have a plate lock on it. That allows you to lock your degree circle to the scope rotation, take a shot while you're set to zero, then lock the bottom motion. Then you can loosen your "top" motion lock and turn to a desired angle. Hope I've helped you and not made it worse. . . Paul   [Reply]   [No Email]
PJH 03-13-2010 17:57:14 71.171.215.99 262150 Report to Moderator	Re: Disregard please....trying photo posting in reply to DENNIS MIN, 03-13-2010 13:31:42   Good Job Dennis - a Dumpy level. You're doing better than me at pictures. Paul   [Reply]   [No Email]
PAGlenn 03-13-2010 16:39:24 76.116.1.225 262144 Report to Moderator	Re: Disregard please....trying photo posting in reply to DENNIS MIN, 03-13-2010 13:31:42   Hey! Nice photo!   [Reply]   [No Email]
DENNIS MIN 03-13-2010 13:33:53 71.48.125.180 262134 Report to Moderator	got it...photo worked this time.... in reply to DENNIS MIN, 03-13-2010 13:31:42   sorry about all the fuss.....   [Reply]   [No Email]