Abrasive block

[Sonic EscapeParticipant @sonicescape38234]

I found this interesting abrasive brick. If feels like putty, just a little more elastic. It cleans the rust very well. It immediately became my favorite cleaning tool. The closest thing I tried was an abrasive sponge. But this thing takes the shape of the object you are cleaning. Very effective and there is little dust. I think the dust is mixing with the bonding material that is consumed.

But like most nice things it is not cheap. But how hard it could be to make one yourself? It is made of SiC + some plastic bonding agent. SiC or aluminium oxide powder is cheap and is available in many places. In all possible grit sizes. I need only to find a suitable bonding substance.

I’m thinking to use this . It is a glue that I used a lot. The nice thing about it is that it remains elastic. I need to dissolve it just a little. Maybe with acetone?

 

 

 

[Ramon WilsonParticipant @ramonwilson3]

This looks to be a similar abrasive product to one I have used for years – ‘GarryFlex’ abrasive blocks. I have cut them to shape with a scalpel to fit various situations, even cutting plugs of it to fit a tube to create ‘engine turning’. They have (had?) four grades – Fine, Medium, Coarse and Extra Coarse – all different colours to denote each grade. Used with parffin (kerosene) or white spirit they put a fine even finish on a surface without polishing it.

They are a great addition to finishing machined surfaces and something that should be in a machinists armoury 👍

Tug

 

 

[bernard towersParticipant @bernardtowers37738]

Well hello Tug, same for me!!. See you next weekend!!!!

[Ramon Wilson]

On Ramon Wilson Said:

This looks to be a similar abrasive product to one I have used for years – ‘GarryFlex’ abrasive blocks. I have cut them to shape with a scalpel to fit various situations, even cutting plugs of it to fit a tube to create ‘engine turning’. They have (had?) four grades – Fine, Medium, Coarse and Extra Coarse – all different colours to denote each grade. Used with parffin (kerosene) or white spirit they put a fine even finish on a surface without polishing it.

They are a great addition to finishing machined surfaces and something that should be in a machinists armoury 👍

Tug

What does the paraffin or white spirit do? It disolves the block and helps with polishing?

[Grizzly bearParticipant @grizzlybear]

Talking of paraffin, I saw a 4 lt. container priced at £15.99 GBP at a large Garden Centre.

We used to wash our hands in it, after a days automobile mechanicing.

[BazyleParticipant @bazyle]

The solvent washes the dust away and lubricates – same as using ‘wet ad dry’ with water.

[bernard towers]

On bernard towers Said:

Well hello Tug, same for me!!. See you next weekend!!!!

Certainly will Bernard 👍

For those unaware and in the East Anglian area there is a two day model exhibition at Lowestoft Technical college Nov 2nd and 3rd that’s well established and well worth a visit – https://www.lowmex.co.uk/

 

With regard to the abrasive blocks – paraffin lubricates the process and give a much better surface finish. It also helps to prevent clogging of the abrasive and does not dissolve the block and neither do any of the usual solvents found in the ME workshop.

Tug

[Sonic EscapeParticipant @sonicescape38234]

I just made my first abrasive block! I mixed silicon carbide (40 grit) with hair removal vax. This vax is harder and more elastic than normal one. A small candle is enough to melt it.

I tested the result on a rusty HSS blank.

As you can see when used dry it is not soft enough to deform to clean the rust in the deep scratches. But after I added WD40 it became quite effective. I’m going to add also citric acid powder. Maybe this will make the composition softer. And as a bonus it will also dissolve the rust, not only grind it.

SiC is very heavy and it sank at the bottom. Still the pill didn’t glazed.

Maybe this will be a problem with finer grits. I have also some aluminium oxide (80 grit) to try. I’m going to cook different recipes 🙂

 

 

 

 

 

 

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