Cleaning a mould with a wire brush can leave tell tale signs....

[Texasflyboy]

When an iron mould is cleaned with a wire brush, some of the brush metal can be transferred to the mould resulting in a color change on the high points of the mould. This is a give away that the mould has been cleaned with a wire brush.

Other signs are rust still existing in the same mould, but deep in protected areas the brush can't reach, such as inside socket head screws.

In my opinion, cleaning a mould with a wire brush nearly always results in the mould being ruined. The edges of the cavity become rounded, allowing finning to occur.

Other signs of poor mould maintenance are egg shaped block alignment holes, where the hinge screw was allowed to become loose and continued use dragged the male pin into the female hole, resulting in accelerated wear (egg shaped) over time.

eBay: 221340371521

[Bullshop Junior]

When needed, I cleaned mine in dawn dish soap, with a tooth brush, and then dried with compressed air.

[bhn22]

My "quick" test for suspect molds is simple. Wire brushing breaks down the sharp edge of the cavity at the parting line. Instead of feeling sharp, the edge will have a smoother, slightly rounded feel to it. If you hold it up to the light, you can see the bevel at the cavitys edge. Pricing and desirability go down from there.

[ohland]

A tell tale sign is when the mold faces are shiny below the alignment pins. When folks use fine emery or high grit sandpaper wrapped around a flat file, it scours away in a straight line. As long as the misguided efforts are below the cavities, it is (fairly) benign. Be alert though if the edge of the abrasive has worn on the alignment pin. Though you could pop the pin and index the worn flat around, it just isn't smart.

Another annoyance is if someone wants to clean lead smears while the mold is cold.

:coffeecom

[Gtek]

I have seen people that can break hammers, some people should not drive cars! I have purchased more than a couple molds/moulds and scrubbed with Phosphoric acid and a bronze brush. Brushing into cavity, not across or out, also have taken carbide and dragged vent lines clean and cold blue when done. Very small parting lines can be diminished or removed by lapping to fit your pipe. Some have dropped beauties and some- well, in the end it all boils down to buyer beware if going used. Throw the dice on a couple Jacksons or get out a C note or two. Gtek