24-03-2015, 04:45 PM
UPDATE: Thoughts welcome with regard to the following issues:
If I'm understanding the head mechanism correctly, the head is supposed to return back to position against a small return spring. The head is mounted on a sliding bracket that's supposed to glide along the chassis. A lever pushes the head forwards by friction on a pointed cam (or whatever) and the spring is supposed to return it.
Here's the problem: It could be a combination of dried grease or simply distortion but the head doesn't exactly slide back and forth. It's easily done with your fingers but the spring doesn't supply anything like that amount of pressure. So, I started by painstakingly lubricating all surfaces in friction. True, one way to do this would be the hard way - take the heads off altogether, clean area and re-grease. However, I tried an oil drip around edges and allowed oil to run behind surfaces using a straw. I thought I'd try that first in case I have a hard job finding new springs or rivets and so on. I know people use lithium grease but this would be hard to drip feed and I experimented with just oil and lots of movement of the parts. It's eased up a fair bit now but definitely not enough for the spring to do its job. I took the spring off as I suspect it's worn out and tired.
I'm a bit bothered by the fact the heads can wobble a bit side to side if you rock them gently. It's not a tight fit and there's play in the rivets.
Anyway, I'm now wondering if I could simply up the spring pressure and also even it out. I find it strange the factory used a return spring on one side so possibly I could add another spring the other side so the pull is distributed evenly, reducing friction on bearings and rivets. I'm going to have a look about to see where I can get springs.
Not sure I'm that keen on the overall design as the eject mechanism very vulnerable to wear and use.
If I'm understanding the head mechanism correctly, the head is supposed to return back to position against a small return spring. The head is mounted on a sliding bracket that's supposed to glide along the chassis. A lever pushes the head forwards by friction on a pointed cam (or whatever) and the spring is supposed to return it.
Here's the problem: It could be a combination of dried grease or simply distortion but the head doesn't exactly slide back and forth. It's easily done with your fingers but the spring doesn't supply anything like that amount of pressure. So, I started by painstakingly lubricating all surfaces in friction. True, one way to do this would be the hard way - take the heads off altogether, clean area and re-grease. However, I tried an oil drip around edges and allowed oil to run behind surfaces using a straw. I thought I'd try that first in case I have a hard job finding new springs or rivets and so on. I know people use lithium grease but this would be hard to drip feed and I experimented with just oil and lots of movement of the parts. It's eased up a fair bit now but definitely not enough for the spring to do its job. I took the spring off as I suspect it's worn out and tired.
I'm a bit bothered by the fact the heads can wobble a bit side to side if you rock them gently. It's not a tight fit and there's play in the rivets.
Anyway, I'm now wondering if I could simply up the spring pressure and also even it out. I find it strange the factory used a return spring on one side so possibly I could add another spring the other side so the pull is distributed evenly, reducing friction on bearings and rivets. I'm going to have a look about to see where I can get springs.
Not sure I'm that keen on the overall design as the eject mechanism very vulnerable to wear and use.
