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Mark 5 to Mark 7 conversion

Posted: Wed Feb 16, 2011 1:11 pm
by Ed in Tampa
Does anyone know if there is any plans for a Mark 5 to Mark 7 conversion?

If the conversion exists does any one know the price?

Last question how is the rigidity of the Shopsmith Mark 7 I would quess it to be a little looser than the present Mark 5

Posted: Wed Feb 16, 2011 1:14 pm
by damagi
When I was chatting with mike at the local demo of the powerpro he said that they were working on an upgrade, maybe in the next month or so. No indication of price though.

It would be nice if they offered a trade-in discount on those pieces like they do for the headstock.

Posted: Wed Feb 16, 2011 1:51 pm
by ddvann79
damagi wrote:When I was chatting with mike at the local demo of the powerpro he said that they were working on an upgrade, maybe in the next month or so. No indication of price though.

It would be nice if they offered a trade-in discount on those pieces like they do for the headstock.
Very cool. I'm thinking the Mark V tailstock probably wouldn't be very valuable to SS for resale so even if they did offer the trade-in I'm betting it wouldn't be much at all.

I'm sure several of you have been toying with ideas of how to make a shop-made version of the new VII. Anybody come up with something they think would work with the existing castings in the market?

Posted: Wed Feb 16, 2011 2:22 pm
by robinson46176
ddvann79 wrote:Very cool. I'm thinking the Mark V tailstock probably wouldn't be very valuable to SS for resale so even if they did offer the trade-in I'm betting it wouldn't be much at all.

I'm sure several of you have been toying with ideas of how to make a shop-made version of the new VII. Anybody come up with something they think would work with the existing castings in the market?


I don't understand??? Exactly why would the existing tailstock not be unusable on a conversion. Did they change more than I was aware of? Except for a few good pictures recently posted on this forum this whole thing is almost like they are afraid to put it up out in the open and show it from all angles and say this is what it is...
My conversion to tilting both ways is going to be simpler and I think stronger than what I saw in the pictures. I intend to just use 2 pivot ends and replace both of the pivot pins with a properly sized pin that is a little longer and tapered at the end for easier insertion in case things were not lining up just perfect. It can be like a common tractor hitch pin like this but must be the right diameter and long enough to stick out the back far enough to slip a hairpin in it to keep it there. Like this:
[ATTACH]11934[/ATTACH]
Just pull one pin depending on which way you want to tip it and tip it up and tighten the regular upright lock knob which would now be on both ends. The latch end would then be the throw away item.
Are they doing something else besides tipping it up two ways?


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Posted: Wed Feb 16, 2011 3:10 pm
by damagi
Realistically speaking, I doubt shopsmith is interested in reusing a bunch of the stuff from old headstocks either...maybe, maybe not. I would imagine its just as valuable to get headstocks off of ebay to shore up the prices. Same would go for the end pieces.

Posted: Wed Feb 16, 2011 4:11 pm
by dusty
robinson46176 wrote:I don't understand??? Exactly why would the existing tailstock not be unusable on a conversion. Did they change more than I was aware of? Except for a few good pictures recently posted on this forum this whole thing is almost like they are afraid to put it up out in the open and show it from all angles and say this is what it is...
My conversion to tilting both ways is going to be simpler and I think stronger than what I saw in the pictures. I intend to just use 2 pivot ends and replace both of the pivot pins with a properly sized pin that is a little longer and tapered at the end for easier insertion in case things were not lining up just perfect. It can be like a common tractor hitch pin like this but must be the right diameter and long enough to stick out the back far enough to slip a hairpin in it to keep it there. Like this:
[ATTACH]11934[/ATTACH]
Just pull one pin depending on which way you want to tip it and tip it up and tighten the regular upright lock knob which would now be on both ends. The latch end would then be the throw away item.
Are they doing something else besides tipping it up two ways?


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What you propose, farmer, works like a champ. If I could buy the tubes with teeth on both sides, so that I could rotate the table in the carriage, I'd be in business.

Posted: Wed Feb 16, 2011 4:18 pm
by damagi
good idea...a longer shaft with pins would work. As dusty notes, the main difference is then having the rack on both sides of the table trunion tubes.

One difference between the MK7 version and what you propose is that yours is subject to gravity/binding/dropping down when you pull the pin, whereas shopsmith's version always rests on the pin.

One improvement I noted on the MK7 ends was that the se screw for the way tubes is now on top of the casting, which is kinda nice.

Posted: Wed Feb 16, 2011 4:22 pm
by damagi
ddvann79 wrote:Very cool. I'm thinking the Mark V tailstock probably wouldn't be very valuable to SS for resale so even if they did offer the trade-in I'm betting it wouldn't be much at all.

I'm sure several of you have been toying with ideas of how to make a shop-made version of the new VII. Anybody come up with something they think would work with the existing castings in the market?
i think the value for SS in trade-ins would be getting parts off the market rather than forcing them into the trash or hittting ebay/craigslist.

If you cut a notch in the bottom of the pivot and then add a bolt to cinch the upper part of the base against the lower part then you basically have shopsmith's version.

btw - I also noticed that ss went with a spring clip rather than a roll pin for keeping the pivot bar in place.

Posted: Wed Feb 16, 2011 4:47 pm
by robinson46176
dusty wrote:What you propose, farmer, works like a champ. If I could buy the tubes with teeth on both sides, so that I could rotate the table in the carriage, I'd be in business.


I am not equipped to hob the teeth but I guess I could use 2 sets of post and slit a section out of the back of the table post and then slice a toothed section out of the second set of post and weld them into the backside of the table post then grind the welds flush. Alignment of course would want to be very close especially between the front post and the back post. I have done stuff like that on farm machinery where removing a bad part was going to be a huge amount of work. Cut out a bad section and weld in a good section from a cannibalized machine. Sometimes proper alignment is critical, sometimes it isn't. :)

Back in the early 1940's (during WWII) it was often hard to get things you needed. My father and a good friend neighbor were building a lot farm machinery from scrap stuff since they could not buy new. My father had a decent blacksmith/mechanics type shop including a good welder and torches but he did not have a drill press or even a good electric hand drill. The old blacksmith drill bits were for black iron and barely drilled steel. They solved the making a good hole problem by saving pieces of old machinery. If they needed a hole they would cut a piece from scrap with a good hole with the cutting torch and weld the "hole" to the piece that needed one... :)
Kind of like walking around the house twice to go in the back door but it worked for them. He saved "holes" for years just from habit. :)


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Posted: Wed Feb 16, 2011 5:12 pm
by Ed in Tampa
I fail to understand why you need teeth on both sides of the posts.
What I do see a need for is for the trunnions to be able to tilt both directions. I think that could be accomplished by cutting down on the trunnion casting to allow the table to tile in either direction.