Member postings for Wal Werbel

Just thought I'd post back with a bit more on how this has gone / is going.

Post polishing, the plaques look like this:

This is a rough vid describing the clean up stages (soap/rinse/alcohol/rinse):

From there the plaques go straight into new plastic bags and won't be touched again until they're up for paint.

Water lies evenly across the floor of the recessed areas after the alcohol has been rinsed off, so should be good.

Wal.

Hehe - yep, it was literally a bit of scrap that I was simply going to drill some holes in - then it turned into an 'evening project'...

Wal.

Many thanks for the replies guys. Much appreciated.

Should finish the machining of this batch by the end of the week, then begins the abrading to soften the edges, then the polishing and cleaning. Some small spaces to get into..!

Wal.

I made myself this tiny tapping block for small diameter work:

When I first started planning to build my little CNC mini mill I figured that I'd need a way to drill and to tap into the edges of alu plate in a somewhat accurate and perpendicular manner, so had this made - those top hats have proved very useful time and time again:

Edited By Wal Werbel on 27/03/2022 23:26:53

So after further reading and taking into account advice given here and my own travails to date, I'm going to go with the following method:

1. Polish as usual
2. Use a detergent to clean off the polishing residues
3. Rinse
4. Use 99.7 pure isopropyl alcohol (RS do 500ml for about a tenner) to clean off detergent residues
5. Rinse, dry and buff

I just don't think there's a way of avoiding detergents and the related surfactants when it comes to cleaning up the black polishing residues that get into the tight areas of detail. The pure IPA should be the final word on clearing off the surfactants that are left behind by the detergent.

Even going with an ultrasonic cleaner you'd need to use a compatible solution/detergent to avoid pitting the metal, but that's perhaps a moot point - these plates are 320x240x6mm so would have to go out of house to get cleaned - sadly, if experience has taught me anything, then it's likely they'd come back super clean but covered in dents and scratches..!

Wal.

Many thanks for your replies thus far.

Steve, being in the UK I'm familiar with CIF - I'm polishing to somewhere just shy of mirror so I fear that the abrasives in CIF might knock that shine off a bit - but hey - it might also make a good polishing compound... Got me thinking now... Had to look up the water break test (https://www.sciencedirect.com/topics/engineering/water-break-test) - nice tip.

How about this?

My Dad had a bottle of this in his drinks cabinet back in the day. You can barely see that it's burning in the daytime. Ask me how I know.

Maybe a trip to the Sklep Polski is in order..?

EDIT: This stuff is never drunk neat - you add it into cake mix or use it in Nalewki (tinctures)...  Or MAMOD burners...  I did put some on my tongue once, which promptly shrivelled up.

Wal.

Edited By Wal Werbel on 26/03/2022 12:36:16

Duncan, why would Teepol be better? Would it not contain similar surfactants/additives? Genuinely interested as I'd buy myself a five litre bottle if it's an altogether better proposition than Fairy...

EDIT:  To be clear - detergent, whichever one I use, would not be the final stage of the cleaning process - I've just found it to be very effective at cleaning out the black deposits left by the polishing compound.  Once this is done, the brass would be rinsed and then 'properly' degreased.

Wal.

Edited By Wal Werbel on 26/03/2022 12:20:05

Yeah, I've had my doubts over the washing detergent, but when I ran my method by the customer service people at the resin company they said it was 'fine'... go figure.

I'm sure that the polishing compound is far from paint friendly too, which is why I seek the ultimate in degreasers for the final stage.!

Wal.

Hello all.

I have a project on at the moment which involves having brass plates coated with resin - here's an example of one I made some time ago, the current project is the same kind of idea.

Before the resin stage I need to polish up the raised details which means that polishing compound packs in to the letterforms and creates a whole world of ball-ache to clean up. I've managed to refine the clean-up technique to something resembling 'tolerable' but I'm stuck for what to use for a final wipe down. In the past I've used fairy liquid, a toothbrush, numerous cocktail sticks, and then hot water to rinse - seems to work okay, but I'd like to know that I'm doing the job 'properly'.

Recently I read a self proclaimed de-facto explanation of how to prep brass for paint where the instruction was to use rubbing alcohol as a final wipe down. Okay, so surgical spirit (or isopropyl alcohol) then. But in many cases off the shelf stuff contains caster oil and will surely leave a residue and I'm not prepared to take that chance...

Am I over-complicating this? Once visually clean do I just paint in meths to all the nooks and crannies and then hot water rinse?

Many thanks.

Wal.

Due to its density I imagine it's as bad to machine as a D3 tool steel (also rated at 20-30% compared to brass). I'd have a go, but probably wouldn't go out of my way to buy a chunk..!

Duncan - good call on the SAE660 - it is available in flats, but so far I haven't found a stockist that does 'em.

Stueeee - that's a lovely bit of casting..!

Thanks again everyone for the help!

Hello all,

Some good information here. Thanks for posting those images Noel - very helpful.

I did some tests a while back for a company who were after a bit of custom signage. That was CNC'd but I added a bit of patina to get a cast look (electrolysis and then acid) - it was in aluminium (pic below) - I get the impression that my customer's after crisp lettering for this job - perhaps I go with CNC-ing the brass and adding patina to the floor where the texture sits?

Thank you fellas,

Yes, of course - that's the straightforward approach, just make the pattern and get it cast. So the next part of my question is how much detail can I expect to lose? As mentioned, I know bugger all about casting and what can be done nowadays. Some of the letterforms get quite small (5-6mm in height, occasionally with serifs) and my customer would be after a specific background 'texture' which may or may not be problematic - I'll post a couple of example pics of bits and pieces I've done for him below.

But of course - if bronze is absolutely what's required then casting it is the way to go, I think that in his mind's eye my customer is seeing a rougher, pitted finish and a greater loss of detail than he'd perhaps want - CNC machining it takes away some of those perils of casting.

Thanks Nick - Yep, I dropped them an email last week - the closest they can do is PB102 or CZ112.

I see what you're saying - although I wouldn't mind facing off both sides, as long as the thickness is there. Machining the letters individually wouldn't work for this job - imagine a long flat bar that gets inlaid into a paving slab - kind of a heritage way-marker.

Many thanks for that info. Hehe - ah yes, it's always the cost that decides..!

Wal.

Cool, well spotted Jason.

I'll drop 'em a line to see what's available.

Cheers!

Wal.

One off - 582 x 98 x 6mm (thickness can be greater, up to 10mm)

Admittedly an odd size.

Wal.

Edited By Wal Werbel on 09/02/2022 16:30:35

Hi Jason,

I looked at PB102 - with a machinability rating of 20% (poor) and requiring copious flood (of which I have but a meagre trickle) I get the feeling that I'd be fighting a losing battle using the tiny end-mills.

Wal.

Hello all.

I was recently trying to get hold of some LG2 (or Colphos 90) but in plate form. It soon became clear that these materials are more widely available in hex or bar and that I'd find it nigh on impossible to buy as plate.

My question is, if I absolutely needed LG2 in plate, how feasible would it be to get a foundry to melt a bunch of ingots and re-cast 'em into plate? Would it dramatically change the free-cutting/weather-resistant properties? Would it end up looking like the inside of an Aero bar?

This is just an idle question from someone who doesn't know all that much - I'll likely go with Naval Brass (CZ112) - not as aesthetically pleasing, but available in plate and meets the hard wearing / good in a marine environment requirements. Not as free cutting, but should be OK - there are a lot of letterforms which will need to be machined using end-mills down to 0.5mm, as in the pic.

Many thanks for your advice, excogitation etc.

Wal.