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Omal Hinge Borer Troubleshooting2/5/21
I recently inherited an almost functional Omal Hinge Boring/Insertion Machine. I believe it is the "Easy Bore" model.
I believe that green button controls pneumatic valve(s) for the main piston, as well as two small pneumatic clamps.
It could be an electrical button in which case valves controlled by it are most probably some solenoid controlled valves (i.e. they open or close with electrical signal).
It could also be just a push button of the pneumatic valve that is controlled mechanically by that button, and the rest of it is inside the control box.
Starting and stopping of the drilling motor is probably controlled by some electro-mechanical limit switches that get mechanically triggered by the head traveling up and down somewhere along the way.
Your pneumatic cylinder is double acting so the problem is with the air supply at the bottom side of it (that's why it's not going up). I would suggest opening that control box and see what's inside, or try to peak from underneath it.
If possible try to read the name of the part, find out what it is and than find locally available equivalent replacement. Save yourself money and time by not trying to find the original part.
"I believe that green button controls pneumatic valve(s) for the main piston, as well as two small pneumatic clamps."
Not the two small pneumatic clamps. That's the black switch bellow :) Sorry.
Thanks for your help.
I am with you on thinking this is an air flow/valve problem, I will follow the air lines as you suggested.
For further explanation, here is how the machine is supposed to work. There is a switch you turn 90 degrees to engage pneumatic hold clamps (that works).
I'll post if I find anything out.
If there's a constant flow of air through the clean-out hose than most probably that is where the machine is loosing pressure and there simply may not be enough of it to pump the piston up.
Sticky valves is my guess. Have you ever added air tool lubricant to the air supply? How clean is the regulator filter? Try plenty of drops of oil in the supply line and numerous cycles to free up the mechanism. Next step is disassembling the works for a deep cleaning and checking the seals.
Thanks Oggie and Tom for your time and responses. I will try everything you all suggested and let you know how it turns out.
To answer you Tom, likely was not maintained with oil.
Tried multiple cycles of oil and it didn't change it's behavior.
Is it likely enough that this has failed and that it warrants buying a new one and swapping it out? Depending on where I purchase, it's around a $40-$50 part. Would I be better off doing some further diagnostic before I begin throwing money at it?
I have never worked on pneumatic tools like this and don't have an understanding of how they operate. Once again - appreciate the help!
It depends how much you value your time.
Replacing that part is straight-forward operation. Those are quick connectors (just push-in to connect the hose, and depress the ring and pull-out to disconnect it), and everything should go very easy. Just make sure you buy new ports (those things that accept that black air-hose); they need to have the right thread size that will fit into your new part and have to accept exactly that diameter of your black air-hose).
I'm not expert on pneumatics, but it looks like every major industrial country has it own standards regarding the threads used in pneumatic/hydraulic industry.
Or, if there's some pneumatic supply shop in your area it may be even faster.
There are a few possibilities;
The seals in the cylinder are the most likely cause.
The green push button valve may not be functioning properly. It is simply a pneumatic valve to route the air pressure to the top or bottom cylinder chambers.
The guide bearings on the posts may be gummed up with dust, debris, rust, etc., but that is highly unlikely
I swapped out the pneumatic valve behind the green push button and am still having the same problem.
I'm suspicious about the seals being the problem, because there would probably be some problems with going down operation and drilling too since it's the same piston that goes up and down.
However, it should not be a problem to open the cylinder.
If I was in your place I would check if that valve at the bottom gets correct control signals.