# adapter plate construction question



## kd0afk (Jan 21, 2013)

A am making an adapter plate for my milling attachment and aluminum is the choice I made for the plate. It need to have a dovetail spud to mount on the cross slide. 
Would it be better to turn the whole thing out of aluminum spud and all or turn the plate flat and make the spud out of stainless? I want it to me sturdy.


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## Rivergypsy (Jan 21, 2013)

Maybe best to give more of an idea or sketch on what you're up to? I'm guessing a vertical slide, but not sure...


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## kd0afk (Jan 21, 2013)

Here is a rendering of it. Not to scale. It is upside down also, the foot will point downwards.


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## pkastagehand (Jan 21, 2013)

.... would be to not use aluminum.  Although maybe a hard one would work.  AL galls pretty easily.  I don't know how well it would dog down.  Or if it galls in use may not want to come apart again.

I did this umpteen years ago on a very old lathe I once had to adapt a Sears milling attachment.  I had a chunk of cast steel or something that I used.  It did work pretty well for light milling.  Made my Lil' Brother on it.

It could go either way on the number of pieces.  I did a one piece.  You could do two pieces maybe loctite to bond or press fit?  Maybe you could get away with AL for the main plate and I am assuming the dovetail nub is where the dogging will take place and I would switch to steel or cast iron there maybe.

Paul



kd0afk said:


> A am making an adapter plate for my milling attachment and aluminum is the choice I made for the plate. It need to have a dovetail spud to mount on the cross slide.
> Would it be better to turn the whole thing out of aluminum spud and all or turn the plate flat and make the spud out of stainless? I want it to me sturdy.


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## jack620 (Jan 21, 2013)

I wouldn't use Al either.  You need to tighten the two screws fairly tight to secure the milling attachment against movement.  There's a very good chance you'll distort an Al dovetail and jam the attachment in the hole in the cross-slide.
Chris


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## kd0afk (Jan 21, 2013)

So a stainless steel spud mounted in the aluminum plate. The plate is 6061 AL. I will be making the plate a full inch thick and threading the spud all the way through with a 1" thread locktighting it in place and probably hitting it with a punch a few times. The shaft the attachment pivots on will also be stainless and threaded into the center of the spud with a 1/2"-20. For some reason the attachment I have has a shaft hole instead of a spud.


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## MachineTom (Jan 21, 2013)

Al is not a great choice even for the plate, instead of threading the AL plate make the spud larger on the top than the bottom(dovetailed end) then have a shoulder to stop it in the plate, and even have a shaft for fitting into the vertical slide. 

The baseplate for the milling vise on my Myford Lathe was no more than 5/8 CI. Find some 5/8 steel plate and mill away.


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## kd0afk (Jan 21, 2013)

Aluminum is all I have to work with and it cost me $25. Unless someone wants to trade me this piece of al for a piece of steel I'm using it.
If I use the aluminum can't I drill and thread it at 1"x20, machine the tapered spud and turn down a shoulder leaving a collar for a shoulder and a 1" shaft  and thread that. Then drill and tap the top of that for the pivot shaft for the attachment. The spud will have a shoulder. I think a lot of the stress would be taken off of the plate this way.


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## kd0afk (Jan 21, 2013)

For anyone who wants to trade, The al is 5" dia. x 1.5"


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## kd0afk (Jan 21, 2013)

There aren't any metal yards around here. Ebay is all I have right now.


MachineTom said:


> ...... Find some 5/8 steel plate and mill away.


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