Originally Posted by Cartierusm  I'm trying to make an adjustable plate for a tripod and I'm going to use the standard 60 degree dovetails. The dovetail needs to fit smooth with very little if no play at all. I am an accomplished machinist but never having made dovetails before I'm not sure how easy it is to get a tight fit that moves easy. Or since most machines use a gib is there always a need to have an adjustment. This is not machinery that's being made so the unit won't be moving all day long. I do have anodizing setup and it will be anodized for wear protection.
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making a very fine fit with a dovetail is no different than other close fit you've machined - you just have to work carefully so there is minimal clearance. that means careful measurement and the trick with dovetails is to use something like ground pins to measure them. work out the math - or formulas are a google away and then then you can mill down a an exact fit, say a thou clearance - pics below illustrate this.
working carefully can make them to where they slide easily but won't fall out under their own weight.....but...if its for motion (as opposed to very occasional adjustments, I wouldn't make one without a gib. Gibs are simple to make, they don't have to be fancy tapered ones, just a flat piece of material with the angles milled on (you used the actual dovetail to hold the gib to mill the angle on).
Also, AL wouldn't be my first choice, esp if there is a lot of motion - you say its not moving all day but also that its anodized for wear which suggest some amount of motion
getting it the right distance from the edge (this is a small adjustment dovetail for a cut knurling tool i made)
adjustable parallel to measure inside
outside is straightforward
