I need a Brake.

[HazlewoodImages]

These are so complex cast steel parts that the chances of a replacement working reliably are pretty small.

A quick solution would be a hinged bolt attached to the column, adjacent to the wheel. This could fold down in order to engage one of the three spokes on this wheel when at rest - or after adjustment. This could be done in suitable style that would not scream of amateur - work. As long as the attachment to the column was secure, this would provide a very safe stand. The challenge would be making an attractive and robust hinging system. The outside half of the bolt could be covered in rubber to reduce noise and dampen impact.

You would still have make a simple bearing, but this would be much easier job than attempting to make an item with double function

I'm having some difficulty imagining your solution. I can't wrap my head around it.

[HazlewoodImages]

Attachment 146490

With dimensions, I could make a better model.

p.s. Fusion 360 model: http://a360.co/2427ymO

I may have access to a complete brake on someone elses stand but I doubt they'll let me remove it nor would i want to be responsible for replacing it if it were to be broken in the process. How can I get you those dimensions and how much would that piece cost me if it were made by you? The link you've provided tells me I don't have permission to access it.

[HazlewoodImages]

I've had some correspondence with Mark Osterman at Eastman House and here's what he recommends:

You have no other recourse but to pin the stand. This means that you clamp the stand for the first position you are likely to use and drill a hole in one of the sliding columns through to the stationary column. Then find an antique door hinge pin (with the round knob on the end) and insert the pin to hold the stand in place.

Once you have established the first position, slide the top of the stand up and down by 2" increments and drill through the hole you made in the sliding column into the stationary column to establish a series of pin stops.

The broken casting is a different story. Remove and replace with a steel fabrication. About the time you do all of this you'll find a better stand for $300 on Craig's list. :-)

[goamules]

There are dozens of ways to fix this problem. You are starting to see some of them. The stand is spring loaded, so there isn't much weight to hold up by the gears. That's the easy part to fix, with a clamp holding the adjacent parts (like that metal fixture above the gear, you could C-clamp that to the gear rail. The bushing for the gear axle is harder, and needs more care. I'd look into getting just that part machined locally by somone. Prop the stand up so you can just take that part off. Take it to a machinist, and say, "make me one of these, with the broken part split like a connecting rod in a car. Two bolts to hold the "cap" on when you get it back in place, and some oil, and you're in business.

Or if you are really a backyard mechanic, get some bailing wire around that part, wrapped several times over the shaft, and around the back of the cast iron. Oil lightly, crank away. You can fix it the right way "later"....

[jp]

I'm having some difficulty imagining your solution. I can't wrap my head around it.

I'm thinking like a strong "knife switch" that engages the gear teeth when you want to lock the height.

[HazlewoodImages]

I'm thinking like a strong "knife switch" that engages the gear teeth when you want to lock the height.

Ahhh yes. Looking at it though,I'm not sure how I would mount that.

[HazlewoodImages]

There are dozens of ways to fix this problem. You are starting to see some of them. The stand is spring loaded, so there isn't much weight to hold up by the gears. That's the easy part to fix, with a clamp holding the adjacent parts (like that metal fixture above the gear, you could C-clamp that to the gear rail. The bushing for the gear axle is harder, and needs more care. I'd look into getting just that part machined locally by somone. Prop the stand up so you can just take that part off. Take it to a machinist, and say, "make me one of these, with the broken part split like a connecting rod in a car. Two bolts to hold the "cap" on when you get it back in place, and some oil, and you're in business.

Or if you are really a backyard mechanic, get some bailing wire around that part, wrapped several times over the shaft, and around the back of the cast iron. Oil lightly, crank away. You can fix it the right way "later"....

I'm liking the idea of having a bushing similar to my in tact one made but instead of a whole round one, have it in two pieces like a pinch clamp with a knob to release the rod slightly for raising and lowering the platform

[Jac@stafford.net]

I'm thinking like a strong "knife switch" that engages the gear teeth when you want to lock the height.

Those teeth are soft and shallow. I'm afraid the knife switch would break them.

[HazlewoodImages]

Those teeth are soft and shallow. I'm afraid the knife switch would break them.

good point

[Tin Can]

I'm liking the idea of having a bushing similar to my in tact one made but instead of a whole round one, have it in two pieces like a pinch clamp with a knob to release the rod slightly for raising and lowering the platform

http://www.ruland.com/ps_collars_shaft_sp.asp