Mark 7

[ray1942]

Methinks the geometry is such that it will 'work' both ways. It will provide less assist in the 'new' direction due to that geometry. Conjecture here, I have never seen it on a 'new' M7.

To my way of thinking, the way the lift assist mounts to the upper & lower way tubes at the pivot end requries a lift shock with a short travel (in inches of travel) to operate. To lift with the pivot point at the other end and without moving the shock mounting point would require a lift shock with a long travel (in feet of travel). To see what I mean look at the pictures of the lift assist on the SS website and watch Nick's installation video linked on that page. http://www.shopsmith.com/ownersite/cata ... assist.htm

Ray1942

[JPG]

To my way of thinking, the way the lift assist mounts to the upper & lower way tubes at the pivot end requries a lift shock with a short travel (in inches of travel) to operate. To lift with the pivot point at the other end and without moving the shock mounting point would require a lift shock with a long travel (in feet of travel). To see what I mean look at the pictures of the lift assist on the SS website and watch Nick's installation video linked on that page. http://www.shopsmith.com/ownersite/catalog/mvmisc_liftassist.htm

Ray1942

I have. Notice the location of the gas tube to the arm attached to the way tubes, and visualize its motion when tilted 'normally' towards the 'right' end.

The arm rotates up to a position almost directly above the attachment point of the other end of the gas tube near the bench tubes.(the gas tube is almost vertical when ss is raised). The path of the other end of the gas tube is circular from a point (below the bench tubes and towards the center of the ss) up to a point nearly above the lower end attached to the bench tube.

Now consider its motion if ss is tilted to the left. The end attached to the arm will move not only up, but also towards the left end(further towards and beyond the center[left to right]). It will start below the bench tubes, raise to a maximum height above the way tubes and then descend all while moving towards the left end. The mechanical advantage(lever arm length) will decrease as the ss is raised.

Not actually having one to observe first hand, this may be hyper imagination at work. I do however think it plausible!

[dusty]

I have. Notice the location of the gas tube to the arm attached to the way tubes, and visualize its motion when tilted 'normally' towards the 'right' end.

The arm rotates up to a position almost directly above the attachment point of the other end of the gas tube near the bench tubes.(the gas tube is almost vertical when ss is raised). The path of the other end of the gas tube is circular from a point (below the bench tubes and towards the center of the ss) up to a point nearly above the lower end attached to the bench tube.

Now consider its motion if ss is tilted to the left. The end attached to the arm will move not only up, but also towards the left end(further towards and beyond the center[left to right]). It will start below the bench tubes, raise to a maximum height above the way tubes and then descend all while moving towards the left end. The mechanical advantage(lever arm length) will decrease as the ss is raised.

Not actually having one to observe first hand, this may be hyper imagination at work. I do however think it plausible!

I have spent more than just a few minutes sitting on a bucket in the shop staring at the Mark V and trying to envision it going left. Frankly, I don't see how it is possible with out a "redesign" for a unit to tilt both directions.

I don't believe the motion of the piston would even be correct.

Furthermore, I have not seen Shopsmith implications that it would work either. There has been some discussion that due to the heavier headstock the lift assist may need a larger cylinder but no discussion of the Mark & Lift Assist at all.

[JPG]

I have spent more than just a few minutes sitting on a bucket in the shop staring at the Mark V and trying to envision it going left. Frankly, I don't see how it is possible with out a "redesign" for a unit to tilt both directions.

I don't believe the motion of the piston would even be correct.

Furthermore, I have not seen Shopsmith implications that it would work either. There has been some discussion that due to the heavier headstock the lift assist may need a larger cylinder but no discussion of the Mark & Lift Assist at all.

True! That concerns me as well! It may be that part of the difference in the gas tube is a 'quick' disconnect fitting on one(both) end(s).

Not having one I am forced to rely totally on conjecture. Some dimensions would contribute greatly to proving or disproving my 'hypothesis'. Distances from right pivot to positions of both ends of the gas tube (both lowered and raised[bench tube end does not change]) and distance below the way tube of the lower(when lowered) end would suffice.

P.S. I believe the assist is provided by gas that is compressed/transferred to the lower end of the tube when the ss is lowered to horizontal after assembly(maybe a spring as well ;>} ). That force would be in the correct 'direction' for left motion as well but less due to angles and lever arm lengths.

[camerio]

You communicated quite well there! Do not be bashful! Come on in, the water's fine!:)

Wow ! "bashful" a new word for me.
Thanks for the invite, I will try not to be so shy.
As far as lifting from both sides, I just cannot seem to see it.
Eventually, we will see some video of the Mark 7 and it will be demontrated.
I cannot wait to see that.

camerio

[ray1942]

I'm waiting for my lift assist to arrive. It has been on back order since
early Oct. When it finally arrives I will attempt to mount it on the oposite end to see if it will work.

Ray1942

[JPG]

I'm waiting for my lift assist to arrive. It has been on back order since
early Oct. When it finally arrives I will attempt to mount it on the oposite end to see if it will work.

Ray1942

Not sure that will be possible since it must be in the vertical position to install the gas tube. The 'opposite' end cannot go to vertical(no hinge).

The dimensions mentioned 3 posts back would be helpful in determining whether this is possible or merely 'wishful thinking(?)'!

[tryinhard]

Sorry about asking this, but I have been gone for a while (probably for the better for the group ).

Before I left, on one of the our forums there was a lot of traffic about one member getting an advanced Mark 7 unit that was offered over the phone by SS before the official announcement. There was promise of pictures to show the new table mechanism and the dual tilting capability. I have tried searches to find these posts, and tried to find the poster (I only remember his location, which is just up the road from me), and have not been successful.

What I read being discussed in this thread, there appears to still be some question as to what all the new mechanisms look like.

Can someone fill point me to the correct thread that has all the pictures and information, or fill me in on what went on?

Thanks, Mike

[mickyd]

This one Mike? Same state as you.

https://forum.shopsmith.com/viewtopic.php?t=6401

[JPG]

This one Mike? Same state as you.

https://forum.shopsmith.com/viewtopic.php?t=6401

More specifically, https://forum.shopsmith.com/viewtopic.php?p=75219&postcount=31

Not shown in his pix is the gear rack on both sides of the table support tubes.

They are there and can be seen in the pix on the ss site that shows the Mark 7 in drill press mode(the rack faces away from the pinion gear(up).

[ATTACH]11054[/ATTACH] [ATTACH]11055[/ATTACH]

Notice in his 4th pix, the teeth are on the other side of the tube, hence they be on both sides!