Epoxy & Steel

In an another thread, the writer is asking about "copper eating handcleaner". I have a query about epoxy resin adhesives, such as Araldite, when mixed with steel filings.

I'm experimenting with the different types of epoxy adhesives I have in that I'm trying to find a combination that looks something like, eg, BMS. Without going into much detail, I have Araldite Rapid Steel, which according to the Halfords advert contains stainless steel, and which is dark grey when mixed and turns black when set. I have also tried both Araldite Standard which is normally clear when mixed and set, and Evostick Rapid which is also clear both when mixed and set. In both these latter instances, mixing steel filings in with the mix causes the resultant set adhesive to turn black, just the same as the Araldite Rapid Steel.

I've also tried mixing aluminium filings, and these produce a speckled look, ie the aluminium filings are suspended in the clear set adhesive. Using a much finer quantity of aluminium results in the same effect, but a much more even and finer look, due no doubt to the finer aluminium spreading out in the adhesive. There is no evidence of any interaction between the aluminium and the adhesive.

The question, then, is why does the steel filings cause the adhesive to turn black? Is there a chemical reaction going on? I find it surprising that both the Rapid Steel containing, as far as I know, powdered stainless steel, and the homebrew using clear adhesive and steel filings, are black.

Any ideas?

Incidently, I have looked around on't'internet, and discovered that I can indeed obtail amounts of powder which may be used to colour clear epoxy adhesives. One of these is aluminium which I may try.

Peter G. Shaw

The very fine aluminium powders will give you close to a steel look when sanded and polished, you need to put as much powder into the epoxy as you can. This bowl was filled with it.

JBWeld which contains metal will dry dark grey and is hard to tell from emery cloth finished cast iron.

Peter,

Have you tried Devcon? I regularly use the Titanium HP putty they produce to repair steel shafts. It is the strongest of all available epoxy mixes and will withstand the highest pressures and temperatures of any of the metal loaded epoxies. I've even used it on hydraulic ram shafts where a burst seal has gouged out a section of the ram shaft. After grinding it is almost indistinguishable from the original parent metal - although obviously not with the hard chrome finish of the shaft!

Expensive stuff but top quality.

Greetings, most metals act as a catalyst for the curing reaction.

Regards

Brian

On seeing the picture, my first thought was that it is not surprising the bowl is empty, its got holes in it! (well you did say it was filled with powder and epoxy) I now see the filler is almost the same colour as the background (could be my monitor though)

Ian P

Hi Ian P, I though the same as you did to start with, but the little bit at the back top, does look steel-ish to me

Regards Nick.

Edited By Nicholas Farr on 03/07/2020 19:15:55

That bowl is very nicely done! I would pay good money for something so nice.

It's possible to buy an enormous range of coloured glitters (usually used for things like nail art) which i fudn worked quite well mixed with epoxy to fill woodwork splits and shakes. The gold colours worked out a lot cheaper than brass fillings (unless you happen to have kept own supplies)

Link example

pgk

Sorry that I don't have the links but I know that you can get casting materials with a metal appearance. I have seen many examples in art galleries and I even knew a chap who would make his own sculptures using an 'epoxy metal'. The manufacturers obviously produce bronze look a like mixes but I am certain they do other colours too.

Phil H

Hi,

I suppose I should really explain what I'm thinking about.

Some months ago, I allowed a relative to do some work on the lathe using my big (160mm) chuck. Unfortunately, part of this work involved boring out the centre and he managed to very nicely gouge the chuck. Ok, Ok, perhaps I should have warned him to use a sacrifical piece of steel, but I didn't, and he didn't, and it got gouged. In fact, other than looking unsightly, it doesn't really detract from chuck usage so I idly wondered about (over)filling the gouges with a suitably coloured epoxy resin adhesive, and then carefully turning the surplus away thus hopefully producing a matching surface to the main body of the chuck. When all said and done, the only usage of the surface involved is likely to be under pressure so no great sticking strength is actually required.

The experiments I've done were with what I had in stock, including some epoxy putty - which didn't work anything like as well as the liquid adhesives. For the record, I mixed up small quantities - of both liquids & putties - plonked it onto a roughly cleaned by filing strip of steel bar and left for two weeks. A second experiment was to try the effect of the aluminium filings as reported above. Incidently, the Araldite Rapid Steel was by far and away the strongest stuck to the steel bar - which is more or less what it claims on the packaging.

Oily Rag,

Devcon - it may be good, but oh, that price! However, I think I may have seen titanium powder on the 'net. If so, then I might try some provided the cost isn't excessive.

JasonB,

Yes, it does indeed look as if a very fine aluminium powder might be satisfactory.

Brian Baker 1,

As the only person to come anywhere near what I actually asked, I wonder if the aluminium, seeing as how it will have an aluminium oxide covering is actually inert and hence shows up as speckled. Thoughts?

Finally, as ever,

My age, and infirmity has actually made me consider buying a 125mm diameter chuck in addition and reserving the 160mm chuck for those occasions when nothing else will do. There are two reasons for this: the first is the weight - I have to have sufficient wood etc packaging on the bed for the chuck to rest on when fastening/removing otherwise I struggle to hold it with one hand whilst inserting the bolts with the other. The second reason is that it only just clears the front of the saddle, hence any extension of the jaws catch on the bed wiper clamp bar, fortunately made from aluminium. I already have a 80mm chuck which I do tend to use quite a lot and I think a 125mm chuck will probably cater for quite a lot more.

Cheers,

Peter G. Shaw

One reality si that you'll never colour match perfectly and alwasy know the iller is there.
Another reality is that over time it isn't going to bother you
Final reality is that life is too short (and shorter for many of us now) and far eastern chucks aren't silly money - Spoil yourself with a nice 6-jaw chuck at a weight and size that compromises?
Like most folk with heavier chucks I have a board to protect the bed and designed so i can just slide the chuck into position - these things just get heavier as we both get older..

pgk