Pete.
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You can't do that. The 'diameter' is a cone that the jaws pull in to. You don't know what part of the cone the jaws were held at when the inside radius was machined.
- Thread starter Guzrik
- Start date
You can't do that. The 'diameter' is a cone that the jaws pull in to. You don't know what part of the cone the jaws were held at when the inside radius was machined.
I assume the outer jaws are tapered so the inner is parallel, are the sides also tapered along the cone?
Something else the OP may have to bear in mind.
Could n't upload a movieclip, so I will try with another picture.
1 is the ram, cylindrical outside conical inside, smallest diameter is at the front. This moves in and out.
2 Outer jaws conical outside cylindrical inside, not tapered along the cone. They rest against a fixed support in the back.
3 Inner jaws cilindrical inside and out. These I have several sets for different diameters hoses, they can be exchanged by turning the clips with the small springs but I want to make new ones because I need a specific profile pressed into a tube.
4 Hydraulic cilinder where the ram moves in and out.
1 is the ram, cylindrical outside conical inside, smallest diameter is at the front. This moves in and out.
2 Outer jaws conical outside cylindrical inside, not tapered along the cone. They rest against a fixed support in the back.
3 Inner jaws cilindrical inside and out. These I have several sets for different diameters hoses, they can be exchanged by turning the clips with the small springs but I want to make new ones because I need a specific profile pressed into a tube.
4 Hydraulic cilinder where the ram moves in and out.
https://www.mathopenref.com/arcradiusderive.html
As long as you can measure the outer jaws accurately this will tell you how to derive the diameter
As long as you can measure the outer jaws accurately this will tell you how to derive the diameter
I started this thread, hoping for accurate and easy way to measure the radius. But now realise that since the jaws all have a radius on the outside and on the inside, and that they are not cut 100% perfect into 1/8 pieces, it is easier and more accurate to work with a marker and find it by trail and error. I am not saying it would be impossible, just too much hassle.
Activity will continue next weekend or so. Thanks again for all the replies.
Activity will continue next weekend or so. Thanks again for all the replies.
Prajna
Fixing things for the love of it
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I know I'm bumping an old thread here but this question wasn't well answered, so here's my input:
This kind of problem is often easily solved by finding one of the many calculators on the net. In this instance I searched "radius from arc" and found the following:
So the OP could simply measure the width and depth of curve (height) of the arc, bang those numbers into the calc form, click 'calculate' and read off the answer to more decimal places than he is ever likely to need.
I've used these calculators for solving many things and for calculating stuff I've forgotten the formulae for. Just work out what you can easily measure and search for an online calculator that will take those inputs and spit out the unknown you are seeking. Hope this will be of help to someone.
This kind of problem is often easily solved by finding one of the many calculators on the net. In this instance I searched "radius from arc" and found the following:
Calculator for Radius of an Arc
www.handymath.com
So the OP could simply measure the width and depth of curve (height) of the arc, bang those numbers into the calc form, click 'calculate' and read off the answer to more decimal places than he is ever likely to need.
I've used these calculators for solving many things and for calculating stuff I've forgotten the formulae for. Just work out what you can easily measure and search for an online calculator that will take those inputs and spit out the unknown you are seeking. Hope this will be of help to someone.
Agroshield
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- 5,382
In principle, yes. In practise, or in this specific situation, no.
His radius is approximately 64mm. He has 8 jaws, so they have an included angle of approximately 45 degrees. Work out the width and depth for those figures and 1mm change in radius results in about 0.07-0.08mm change in depth. So for this situation, the calculated radius is extremely sensitive to very tiny errors or uncertainties in the depth measurement.
8ob
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- Nescient in the vale
It would be a lot easier to reverse engineer the jaws, each ferrule type has a crushed diameter, the jaws/segments in the fully closed position need to get that ferrule to size before they bind.The make of ferrule will determine the diameter and once the jaws are made you have to stick with that make.
Bob
Bob
This project is parked but not finished, therefore it is not a failed project
.
I did make two sets of jaws and reported with pictures somewhere else on this forum. The radius was indeed 63.5mm.
They worked very well but I wasn't happy with the impression they made. So I started modifying them and welded all eigth back together and put them in the lathe, wich obviously didn't work. Then I started to mill them individually but since the ChrMo got hard spots from the welding I now need a more serious mill, so I lost interest and put all of the parts in the FutureProjects drawer.
.I did make two sets of jaws and reported with pictures somewhere else on this forum. The radius was indeed 63.5mm.
They worked very well but I wasn't happy with the impression they made. So I started modifying them and welded all eigth back together and put them in the lathe, wich obviously didn't work. Then I started to mill them individually but since the ChrMo got hard spots from the welding I now need a more serious mill, so I lost interest and put all of the parts in the FutureProjects drawer.
