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How to adjust a microstop countersink cage?

rotoiti

rotoiti

Well Known Member
My countersink cage and cutter kit from Avery came with no instructions. I am not sure how to set it for a proper c/s depth. I see no markings on the cage itself.
 
What you have to realise is there is a Microstop Gremlin that sits in the workshop.

You have 2, one is 3/32, the other is 1/8.

No issues.............

However, you come to use it after some weeks and the thing...... well, it just doesn't cut the same, so you have to fiddle and faffle and re adjust the darned thing.

As time moves on, believe me, you acquire an art - it is called the suicide deburrer countersink method.

Not something from Kill Bill, just a knack to use your deburrer to countersink the odd hole to accommodate a rivet :D:D
 
Heh, so I was expecting a bit more science to it. I did my practice piece by trial-and-error and thought that there must be more to the adjustments :) Apparently, there isn't.

Thanks all for the replies!
 
The practice piece you mention is the key

Never do your first cut on the real part or assembly and try to do everyone straight with a similar amount of pressure. In rare cases I had to use a bare countersink cutter and that really make you appreciate the tool.

Bob Axsom
 
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Buy some cheap aluminum angle from ACS, something easily clamped in your vise or to your bench, and use it for setting and testing every time you need to change.
 
Just a little warning.
Pay attention when machine countersinking holes in a corner of a part (end of wing spar for example). If you are not straight you will remove too much metal.
Now I believe you have some holes to countersink. ;)
 
+1 what Bob says.

I set my csinks up for flush and marked the cages with red fingernail polish so I could find flush again after using them for countersinking under a dimple. Even so, using the practice piece to check first, the flush setting has moved a few clicks over time. I also drill and dimple a small piece of aluminum the same thickness as the skin I'm planning to use to gauge the correct depth of the underlying countersink (also on scrap first).

I've also resorted to using a deburring tool when room is an issue or I want to slowly get to the correct depth, and definitely for 1097 rivets for plate nuts.

==dave==
 
AND, don't forget that the nut that secures the cage after setting has LEFT HANDED threads. :)

Bird
 
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Go on ebay and buy a second or third one.. then you can have one for each size - Nice to not have to re-adjust when you change the cutter. With a 3rd unit - you can cut away half the cage in case you need to do a CS in a corner or close to an angle.
 
Cutter Type

What is the best type cutter to use? I have seen single to triple on
the bits. Comments appreciated.
 
I have both single and triple cutters and find they both cut well. The think the key is high cutting speed - + 2000rpm and a sharp cutter (i.e. not old and worn)
 
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