Tool Turret Problems on Mirac

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blacksofstichill
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Tool Turret Problems on Mirac

Post by blacksofstichill » Tue 18 Apr , 2006 23:14 pm

Hi there.

I hope someone can give me some tips with this! I have a 1994 Mirac with the 8 Station Tool Turret which I bought from my old College when they stopped their engineering courses. A few weeks ago it developed a problem where it changes to the wrong tool (e.g. loads tool 6 instead of 7) but actually thinks it has the correct tool loaded. I adjusted the rotation sensor slightly which seemed to sort things out at the time.

However, over the last two weeks there has been a ticking noise whilst the turret is rotating and tonight it has started to load the wrong tools again! When I removed the aluminium cover over the rotation sensor it had coolant inside it despite the cover being well sealed down. Is there a seal from the front of the turret which may have failed?

I have a manual for the machine but in typical fashion I don't seem to have the page with the parts diagram or list for the turret.

Does anybody know anything about the following:

1. What may be causing the ticking noise?

2. Where might the coolant get into the housing about?

3. Is it normal for the rotation sensor to require regular adjustment or is this problem caused by turret wear/coolant ingress?

Sorry for the massive explanation!

Best Regards,

Gary

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Post by Denford Admin » Wed 19 Apr , 2006 9:24 am

Hi,

As have have used a few different types of turret over the years, can you get some more details of the make and model ? - Some have name plates on them.

If we know which one we are talking about, we can see what further info we can find.

Regards,
Admin

blacksofstichill
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Post by blacksofstichill » Wed 19 Apr , 2006 9:34 am

Hi again,

There are no name plates on the Turret but it has a red painted square block below the drive motor with a large Machined 2-piece Aluminum Housing behind it which has the Rotation Sensor in it. I had been told that it may have been a turret manufactured by yourselves. I can check more details tonight if required, just let me know what I need to tell you.

Cheers,

Gary

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Post by Denford Admin » Mon 24 Apr , 2006 13:45 pm

Looks like no-one else is going to help you, so all I can do is tell you what I know:

Sound like its the Denford DM08 turret
As far as I know this has an 8 way rotary switch which can be aligned slightly to get the turret to hit the right positions. If it works sometimes and not others, then its probably the switch itself thats worn or the contacts are dirty (also check the wires and joints for corrosion or breaks)

Apparently there is a large machined alloy block which covers it all up with an o-ring seal.

The logic is:
run motor forward looking for a binary match to the requested position + the strobe input
reverse motor and look for clamped input
stop the motor

I think older machines had the logic as a hardwired relay board - newer ones use the Baldor controllers logic

blacksofstichill
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Post by blacksofstichill » Tue 25 Apr , 2006 22:59 pm

Hi again,

Thanks for the info, that does sound exactly like what I have, with the O ring seal, etc.

I took the rotation sensor to bits (not recommended for people with big hands, very fiddly!), cleaned all of the contacts for each of the tool positions and put it back together again. I adjusted the sensor until it looked like it was aligning itself properly.

Due to the problem I have with the coolant getting into the sensor housing I decided to drill and tap a small drain hole in the bottom of the housing......This way I can take a drain plug out after using the Lathe and I will be able to tell if there is coolant in the housing or not without removing the cover.

The ticking noise when the turret rotates is still there but as long as everything still works it should be okay I hope!

I would like to replace the seal (if there is one) to stop the coolant getting into the sensor housing though, can anyone provide me with an exploded diagram and parts list for this turret?

Cheers,

Gary

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Post by Steve » Wed 26 Apr , 2006 8:45 am

I will ask our drawing office if they can find a drawing and e-mail as a pdf to you.

Regards,

Steve

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Post by Denford Admin » Wed 26 Apr , 2006 10:27 am

Get the full assembly dwg here: http://www.denfordata.com/projectimages ... rawing.pdf

Here is the section view of the DM8 turret to let you know if you have the same one:
Image

blacksofstichill
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Post by blacksofstichill » Wed 10 May , 2006 13:02 pm

Hi again,

Sorry for the delay in getting back to you......That does look like the correct turret, I'll have a closer look at the downloaded drawing and see what parts I might need.

Many Thanks for your help!

Gary

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