Atlas 7B Disassembly and Teardown! Pic Heavy!

Weldo

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Heyo! I've not found a good resource for this subject so I'm gonna try my hand at supplying some info to the community.

Backstory, I got an Atlas 7B just a few weeks ago and upon close inspection it appears someone had lubed it all up with heavy grease as opposed to the recommended No. 10 or 20 oil. So in the interest of keeping this thing in top shape I want to disassemble it as much as possible and give it a good cleaning/lubing before I start to use it. After all machines like this will become more and more rare as time rolls on so I think we in the hobby have a duty to preserve them as best we can. I don't really think of this machine as "mine", rather I am its current steward. Someday, God willing, some other person will enjoy it for many years to come.

On to the greasy stuff!

The following pics are the state of the machine as received.

Under the grease cup on the right side (as viewed by the operator) of the pinion shaft someone had pressed in a zerk fitting thus rendering the grease cup useless.

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This may seem to be an upgrade at first but as I found out on my Atlas lathe countershaft, the temptation when using a zerk and grease gun is to apply much more grease than necessary. Even one pump of the gun is many times more than needed. A grease cup should be turned about one full turn each time the machine is used. This meters out a very small amount of grease, just enough to squeeze a little fresh lube into the bearings. This zerk will be removed and lubing will be handled by the grease cup.

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This is the opposite side of the same pinion shaft. It should have a grease cup similar to the pulley side. The cup has been replaced with a zerk. Based on the huge globs of grease inside the machine it is evident that too much grease has been pumped in.

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A closer look. This fitting will be replaced with a grease cup that has 1/8"- 27 NPT threads. Again, a single turn of the cup each time the machine is used will supply adequate fresh grease.

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Next, the manual calls this part the "Neck and outer bearings" for the large crank gear inside the machine column. This too should be an oil cup and lubed with No. 10 oil. Here you can see it packed with grease.

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This grease must be flushed out.

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In this pic we can see grease applied to the ram. On my machine there was a zerk fitting on the left side ram slide and just an open hole on the right. The factory spec for this is again light oil, the idea being that the ram will "float" on a film of oil like a car's crankshaft and connecting rod bearings. The ram will be removed and cleaned and lubed with oil.

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Finally here are several shots of the internal parts inside the column. The column casting houses the main crank mechanism. Oil is spec'd for all these parts with the exception of the gear teeth. The gear teeth are recommended to be occasionally coated with a small amount of "graphite gear grease".

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The amount of grease inside the machine is excessive and will be thoroughly cleaned out. As mentioned before all the parts inside the column are to be lubed with No. 10 motor oil or equivalent.

The grease used through-out this machine may not technically be bad for it but it does have a few negative aspects. One drawback of grease is the lack of cleanliness in operation. Any machine in which grease is so heavily used will inevitably leave your hands, clothes and tools also coated in grease. Grease will collect dust and grit more so than oil. Because it is so sticky it is not easy to flush out debris from grease coated parts like it is with oil. Since oil is relatively thin and fluid, any accumulated dust and tiny chips can be flushed out with liberal application of more oil. The excess it then wiped up and a clean machine is obtained.

So this is the start of my journey into the Atlas 7B! Stick around, I'll be posting lots more pics and detailed tear down info in the coming days/weeks. Hopefully this will help future hobbyists!
 
First up, Ram removal! Due to the length of the process this will be broken up into a few different posts.

Let's get dirty!

First remove the ram adjusting handle. You will have to remove the oil cup first to allow the handle to thread off the stud.

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Inside the casting are two slotted screws. Remove them as well.

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Now the block can be removed.

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The next most obvious thing is the ram guides. They hold the ram in its channel. The bolts are 1/2". That hole you see is where one of the zerk fittings was. It should be an oil cup.

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Atlas seemed to make extensive use of serrated lock washers.

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All bolts removed. The round head screw in the bar just holds a light bulb bracket. It can stay in place.

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The hold down bar is lifted up and we find a stack of very thin shims. The manual says this is a stack of shims consisting of four 0.002" leaves and two 0.001" leaves, so 0.010" total. Thus adjustment can be made in 0.001" increments to account for wear of the ram or its ways. If play in the ram appears worse than the spec'd 0.001-0.002", a shim can be removed to allow the hold down bar to clamp the ram more tightly.

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Next the bolts for the right side are loosened.

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And we can see the shim stack for the right side.

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Now the felts and wipers must be removed. There are two slotted screws in each one.

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Felts and wipers removed. In this pic we can also clearly see the adjusting gib for the ram.

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The right side wiper revealed a broken screw. The lower screw is broken off in the hole, the sharp break snagging some felt. I may attempt to remove it but it's probably not critical.

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At this point the ram can be lifted from its ways. There was significant suction holding it down due to the grease. In the pic it is propped up on a cedar shim.

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Another view of the underside of the ram from the front. There's still some linkages holding it to the machine.

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It appears that the ram adjusting rod must be freed somehow in order to remove the ram completely. The ram adjusting rod runs parallel with the ram inside the ram. It's a small Acme thread like the one on a lathe cross slide. We can see it in the above picture running through the block in the center of the ram. This rod is the means by which the ram position is adjusted.

Before the rod can be removed be sure to turn the square key at the rear of the ram such that the cast iron block into which the adjusting rod is threaded is somewhere in the middle of its travel. If the block it all the way towards the front of the ram, there will not be enough room to allow the rod to be separated from the ram. This will be important later.

We'll start by removing the lock nuts at the rear of the ram.

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Behind the two nuts is a brass washer.

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The next part took me a while to figure out. There is affixed to the threaded rod a bevel gear. This gear is pinned to the threaded rod with a solid pin and must be removed in order to separate the ram from the linkage underneath. The trick is to use a small punch and tap out the pin through the oil hole at the rear of the ram. Let the ram overhang the column to the rear and turn the threaded rod until the pin is lined up vertically with the oil hole on top of the ram.

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The pin taps out fairly easily. Be careful it doesn't hit the floor and go missing!

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This is where it is important that the cast iron block was moved to about the middle of its travel on the adjusting rod. It the block is located all the way to the front of the ram there will not be enough clearance for the rod to be tapped forward within the ram. The block will hit the front end of the adjusting slot in the ram.

Now that the bevel gear is unpinned from the threaded ram adjusting rod we can tap the rod toward the front of the machine. The pic is just for illustrative purposes, in actuality I used a wood block between the hammer and rod. Protect those threads!


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Here the rod is pushed all the way through the ram.

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After passing through the ram enough the rod drops out of the way. Light can be seen from the other side of the hole.

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At this point you can reach underneath the ram and slide the bevel gear off the threaded rod.

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This is the bevel gear and its pin.

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Now the ram can finally be removed. You lift straight up and you may have to move it to the rear a bit to disengage the threaded rod from it's bore. What's left is the linkage with a threaded rod and the cast iron block still attached.

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Hopefully it's clear from this pic why the cast iron block has to be placed toward the middle/rear of its travel. You must tap the rod a few inches toward the front of the machine to get the rod to clear its bore in the ram. The slot in the top of the ram will limit how far the block can move.

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Another view.

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Now to remove the block and rod.

There's a set screw that holds the large pivot pin firmly in place. 1/8" allen.

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Remove it all the way. Just backing off slightly is not enough since there is a flat spot milled into the pin for the set screw. If you only back it out a 1/2 turn or so the screw will catch the shoulder of the flat spot.

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The pin was tight on my machine so I used a brass drift to tap it out.

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I then had to prop up the linkage to allow room for the pin to pass by the ways. A small wood block was used.

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Try not to let the pin fall to the floor, roll under a table, disappear for a few minutes and get covered in saw dust and spider webs.

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The ram position adjusting rod and block can now be removed.

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The following pics show the bevel gear that mates with the one on the adjusting rod.

Here it is on the underside of the ram.

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The collar on the top side must be removed via a set screw.

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Then the gear can be passed through and out from the bottom.

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That's all I got done so far. Stay tuned!
 
Oh! More info! Thanks man!

To be clear this thread is certainly not meant to be a definitive work on the proper disassembly of this machine. This thread is just how I managed to muddle through the process. There are probably better ways to do everything I attempt!
 
Great job on the photo disassembly. I am still not sure about the oil gitt in the "Neck and outer bearings" assembly, it has two taper bearings, I packed them with grease at the time of reassembly. I did install a new gitt oiler, but have still not put oil in there. I am not sure how oil would get to the bearings in the first place, it is a pretty good distance between the bearings and oiler is in the center space between them. To me it didn't make sense, they grease the back bearings, but not the main bearing and it's turning a lot slower speed. When you think about it, it is a lot like front wheel bearing in a car, two tapered bearing with a place between them. Also grease is a lot better these days than in the past, so don't turn the grease caps as much as was recommend by Atlas. I did talk to a friend that was an application engineer for Chevon, he recommend a grease that would do the job. But, I over oil the thing, especially the sliding block and the ram. I also modified the oiling groves on the ram ways, gib, sliding block for better oiling placement.
 
Oh wow, thats great!

I'm actually surprised about the ZERK on the pinion 'other' side (side with the door) isn't original. Mine 7B is basically factory-original with the exception of that (and the missing oil cup on the other side). I've now ordered _2_ of the oil cups from your last thread, I guess I'll be replacing both :)
 
But, I over oil the thing, especially the sliding block and the ram. I also modified the oiling groves on the ram ways, gib, sliding block for better oiling placement.

Same here :) My shaper looks like a crime-scene with Vactra2 instead of blood. I basically hose down anything/everything with oil whenever I use it.
 
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