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Focus wont stay when let go of knob. how do you lock and hold .is the focus knob supposed to feel loose slides in and out but also moves up down left and right.
The focus knob is not supposed to feel like that. On my Celestron it had almost become detached from the focus lever which attaches to the main mirror inside the tube. There is a threaded shaft and locknut which had become loose.
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Is the ignition sparking? When you press and hold down the buttons, the ignition should be sparking at the centre electrode. At the same time when you hold the buttons down, the gas valve is manually held open to release the gas. The spark is then supposed to ignite the gas. Hold the knobs down for about 3 to 5 seconds after ignition and the gas valve will stay on. If it lights but the flame wont stay on, it could be anything from a partially blocked aeration port to a worn knob. When you push down on the knob, it is supposed to press down on an electromagnetic lock which keeps the gas valve open when the flame is burning. When the knob or shaft isn't pushing down enough, it doesn't keep the gas valve locked and the flame will go out as soon as you let the knob go.
This sounds like a bad activating circuit. The ignition switch is suppose to send juice to the Alternator. Also the plastic plug connectors holding the small wires into the Alternator can ride up and miss the metal tabs they are suppose to fit on. Mechanics often pull the metal connectors out of the plastic connector, then slide the metal connectors onto the Regulator tabs inside the Alternator opening. The Mechanics slide the plastic connector housing over the already attached metal connectors and call it a day.
The Celestron manual for this scope has nothing to say, but on the underside of the focuser assembly, between the 2 focus knobs, you may see 2 screws. They might be thumbscrews or some other screwhead type. One is the adjustment for the focuser internal clearance, or looseness, and the other is a focus travel lock. If present, try backing both off 1/2 turn from tightness, and then experiment to see which is which. The focus lock will have no effect until tight, when the focuser will cease moving, as is now. The other screw will gradually remove looseness and rattle from the focuser until it just moves smoothly, with no back and forth loose feeling at the knob. If neither of these screws is visible you will have to take it to a binocular and telescope shop, where they should not charge much.
The knob you are talking about is called the x-axis control knob. It does not directly affect the focus. What affects the focus is the slight manipulation of the stage and or slide while you are adjusting the x-axis control knob. It only takes the slightest pressure to throw the focus off very far. Theoretically you could completely remove the specimen holder and move the slide around with your fingers.
The specimen holder may need to be replaced but without further more detailed knowledge of the mechanical problem I cannot instruct further.
theres locking pins that hold it in gear that kind of resemble a door latches it`s my guess that there springs are no good and they just are staying open allowing it to slip back out of gear.
The right hand shaft knob contains the coarse focus locking clutch adjustment mechanisim( big name-simple design). This solution applies if you have the model with the fine adjustment wheel mounted in the base and may or may not apply if your fine focus is in the left-hand knob.
Inside the right hand knob ( as viewed from the rear of the scope) is a threaded disk/nut which has two pins (Slightly and for reasons I don't understand: they are offset vertically, they have different pin diameters and different pin lengths) In theory, they lock into the bushing within the knob proper to keep tension on the clutches while keeping the knob from falling off.
The repair can proceed in two ways depending on if the disk/nut has totally been unscrewed from the focus shaft.
Gently pull the left knob and as you do turn it slowly to see if the pins reseat. If they do you'll feel a slight lurch outward of the knob. Hold gentle outward tension( so as the pins remain seated) as you turn the knob clockwise until the slippage in the clutches is so lessened that your knob is firm and the focus adjustment is operating to your liking.
IF that didn't work it is likely that the threaded disk/nut has come off the shaft and will need to be reset and screwed back down. The disk is easily cross threaded and you'll need tweasers or micro plyers or a hemostat and/or a flat headed finishing nail. Plus I recommend a small bottle of LOC-TITE(tm) semi-solid thread sealer--NOT the kind that freezes the threads
As you unscrew the knob counter clockwise pull on the knob to slid it off the shaft it should come off in your hand revealing about 6-8 washers on the shaft. These are the clutches so be careful not to loose them.
The knob should have a slight rattle and that is the disk nut. To get to the disk/nut put a small finishing nail head first into the shaft whole and push to release the plastic knob insert cover out being careful to not loose the disk/nut.
To clean the threads and insure an easier repair screw the disk onto the focus shaft to insure the threads are clean.
This next part works better with the scope lying on its left side.
This part is optional but not necessary to get the scope back in operation. Place a tiny amount of LOC-TITE thread sealer on the shaft threads. This will make the knob clutch adjustment more stiff but will also reduce the likelihood that the knob will be adjusted out too far again. The loosening occurs when the knob is turned before the operator realizes the pinion gear limit has been reached or by someone who dosen't understand correct opperation of the focusing assembly.. So long as the clutches are engaged the and there is no slack in tension the disk/nut shouldn't come off the shaft again.
Observe the pins in the disk/nut and match them up with the holes in the aluminium/brass knob bushing. You'll have to wiggle the disk around to get it reseated properly. Once you do, hold the disk firmly against the bushing to keep the pins seated as you put the knob back over the shaft, pushing it all the way down against the shaft.(The clutches are springy so don't worry about it locking in place just now).
You may prefer to hold the disk/nut and knob firmly with a finger and spin the left hand knob counter-closkwise for easier threading of the nut but remember this will also move the focus arm. Not a problem if you start with the focus in the range centered.
If using the right knob: Turn the knob clockwise feeling for the threaded shaft maiting back up with the threads. IF it cross-threads, back it off try again. Once the threads are engaged keep the outward tension on the knob so the pins don't slip out. When you/ve screwed it down far enough, the clutches will take up the slack and keep the knob from slipping away from the disk/nut. You'll know the clutches are engaged when the focus shaft turns.
If you are happy with the repair slip the knob cover back on and snap in place. It if falls out place a little of the thread sealer on the rim and try again.
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The smart mix knob is connected to a piston that slides up and down into the automix assembly. This piston has come off of the smartmix knob and left the unit on water only setting. Sometimes the smart mix knob breaks on the bottom side letting loose the piston.
This can be a difficult repair. You have to unscrew the flow indicator window and remove the fan and screen(pay attention to how they come out, most people want to put the pointed end of the white screen down. It goes up.) Place a piece of 2X4, a book, something underneath the machine, between the rear wheels. This will lift the wheels into the air, and keep everything in place when you remove the hood. Take the 6 screws out that hold the hood and lens. As you remove the hood try to do it slowly and pay special attention to any hoses that might try to pull off with it. If you don't get those hoses back into the right place, the machine will not work. The piston will probably be stuck into the automix assembly when you get the hood off. It is a three inch black cylinder with an O ring on it. If you hold the hood upside down and place the cornered side of the piston into the corner of the housing between the knob and the solution chamber, you should be able to hook the winding on the knob with the piston and then turn the knob to screw the piston down into the windings. It won't lock into place, but hold it there well enough to put the machine back together correctly.
If you feel like you're forcing something when putting the hood back on, you probably are, so stop and check to make sure all the hoses are where they are supposed to be.
The smart mix knob is connected to a piston that slides up and down into the automix assembly. This piston has come off of the smartmix knob and left the unit on water only setting. Sometimes the smart mix knob breaks on the bottom side letting loose the piston.
This can be a difficult repair. You have to unscrew the flow indicator window and remove the fan and screen(pay attention to how they come out, most people want to put the pointed end of the white screen down. It goes up.) Place a piece of 2X4, a book, something underneath the machine, between the rear wheels. This will lift the wheels into the air, and keep everything in place when you remove the hood. Take the 6 screws out that hold the hood and lens. As you remove the hood try to do it slowly and pay special attention to any hoses that might try to pull off with it. If you don't get those hoses back into the right place, the machine will not work. The piston will probably be stuck into the automix assembly when you get the hood off. It is a three inch black cylinder with an O ring on it. If you hold the hood upside down and place the cornered side of the piston into the corner of the housing between the knob and the solution chamber, you should be able to hook the winding on the knob with the piston and then turn the knob to screw the piston down into the windings. It won't lock into place, but hold it there well enough to put the machine back together correctly.
If you feel like you're forcing something when putting the hood back on, you probably are, so stop and check to make sure all the hoses are where they are supposed to be.
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