# What is it?



## murrayis (Aug 20, 2010)

Hi
Can anyone identify the object in the pictures. This item is in the collection at a Maritime Museum that I do work for.
There is a weight that when released induces a deflection on the scale, but to what purpose? It stands about 600mm tall. Was it used ashore or afloat?

Regards
Rob


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## Duncan112 (Dec 28, 2006)

Tempted to suggest that it is some variant of a hardness testing machine, the weight when released falls on the pin at the bottom which forms a depression in the material underneath, inducing a deflection on the scale. If it's not too delicate try it on a steel block?

Other wiser members may have different ideas though,


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## Ian J. Huckin (Sep 27, 2008)

Duncan112 said:


> Tempted to suggest that it is some variant of a hardness testing machine, the weight when released falls on the pin at the bottom which forms a depression in the material underneath, inducing a deflection on the scale. If it's not too delicate try it on a steel block?
> 
> Other wiser members may have different ideas though,


Yes, that was my first impression too. Maybe a clue would be in the manufacturers name (as in Brinell) or perhaps the scale markings.


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## Satanic Mechanic (Feb 23, 2009)

It has all the appearances of some sort of hardness tester - have you got a photo of its underneath please


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## chadburn (Jun 2, 2008)

This portable drop tester I would have thought was "home made" (although I stand to be corrected) rather than a from a "Professional" Instrument Maker, could be an early method for testing Shore Hardness.


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## Alex Salmond (Mar 7, 2011)

At my work we have similar ,mostly home made devices, that were made in the workshops by fitters yonks ago but which still do the job they were intended for could this be some kind of impact tester like we have ,where different weights are dropped onto a piece of barrier film from a set height to determine film strength,but a shore hardness tester sounds good too ,this tests the hardness of a sheet of rubber.


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## murrayis (Aug 20, 2010)

Thanks for the responses. I'll try and get a photo of the underneath. Our first thought also was some sort of hardness tester. Vintage unknown.
Rob


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## Powertrain (Jul 15, 2011)

I think, as a variation on the theme of harness testing, it tested the degree of rot of ships timbers. I was involved in the testing the suitability of hardwoods to being buried in soil and immersed in salt water when used on making jetties in Fiji many years ago and we had to test specimens every month for the degree of shrinkage or swelling and the change in hardness of the wood and the depth of the deterioration. Such an instrument might have been useful in a dockyard treating wooden ships


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## murrayis (Aug 20, 2010)

Thanks Powertrain

Thats an interesting idea. We are trying to contact the person who donated the item for more information but so far no joy.

Rob


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## jimmyc (Dec 28, 2005)

Spoke to a couple of guys here , one a engineer another a shipbuilder and both think it's a device for measuring the impact on an object, ie. steel. 
The weight is a known amount. when released it strikes the pin at the base and the force is registered on the scale. would possibly be for impact resistance or density. 
Most probably used ashore in shipbuilding.


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## Derek Roger (Feb 19, 2005)

Agree it seems to be some sort of impact tester . A bit primitive in that there would be a lot of friction between the falling weight ( weights including the ball at top ) between the guide bar which is for some reason square and the side supports . Do not think it is for testing steel etc. Wood as suggested would make sence . The calibrated measuring device which seems to have a vernier indicates that it would as suggested be used on wooden vessels to test the strength of materials during construction / repair . It would be a comparitive test ie there would probably been a scale of tests done on various woods ; oak / aged oak etc . and this would be a comparitive test for shipbuilders / repairers to know what material they were buying / using in their vessels .

A most interesting post .

Regards Derek


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## murrayis (Aug 20, 2010)

Thanks Derek & jimmyc.
The other question is why have the cylindrical mass and then a separate spherical mass. Does the sphere act as a rebound dampener or is it a quick way to vary the strike mass for different materials? (change spheres)

Rob


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## jimmyc (Dec 28, 2005)

murrayis said:


> Thanks Derek & jimmyc.
> The other question is why have the cylindrical mass and then a separate spherical mass. Does the sphere act as a rebound dampener or is it a quick way to vary the strike mass for different materials? (change spheres)
> 
> Rob


I would suggest the cylindrical mass is the *known weight* 
from the *known height*
the spherical mass is the *known shape* as to the effect of impact
(Its shape could be like a pin as well for impact
known shape)
*reference to them both according to the scale*
regards Jim


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## gwzm (Nov 7, 2005)

It sure looks like a portable variation on a laboratory steel hardness tester. Some of them (used to) use a calibrated weight with a diamond point mounted on the end of a free-swinging lever-arm.

gwzm


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## Derek Roger (Feb 19, 2005)

I think that were different balls for each type of wood being tested l each one would have a different mass . The cylinder would be the basic mass for the test . ????
Derek


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## jimmyc (Dec 28, 2005)

I think this instrument is extreemely similar
Shore Scleroscope
http://www.tpub.com/content/aviationandaccessories/TM-43-0106/css/TM-43-0106_295.htm


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