Re-casting LG2/Colphos 90 into plate form

There is certainly some loss of crispness in the castings Noel shows, crumbling edges of the sand are often the cause just look around the back half of the rear wheel or where the sand broke away between the front wheel and the "E" of Reeves. It would really depend on what your client will accept

If the part is indeed going to be walked on then Loctite may not be ideal, It's OK on a decorative part as I've done similar with epoxy but in those cases it would only have been subject to light handling. These letters were "roughed up" to make them look more like they were cast. 

PS that is not lettering stuck onto aluminium, just the machined background reflecting light differently

Edited By JasonB on 11/02/2022 07:26:13

The reason I used the reeves casting was to illustrate the detail it is possible to get. The pattern was far from perfect and the reason I still have this is it was the reject and no rectification work was done on it . If this casting was viewed from 3' away rather than 3" then the imperfections would hardly be visible and set in a pavement not noticed at all. Obviously it depends on what the customer wants or will accept - A modern CNC made item or a traditional casting ? I like Jasons mention of roughing up to make a CNC job look like a casting ! Noel

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?

It might be worth buying a small piece of pb102 and seeing how it machines, although most sites as it is 20-25% machinable that is when compared with hard brass as being 100% and brass is very easy to machine. Different if they said it was 20% of tool steel!

As Noel say a lot will depend on how your client looks at things, I always spot things on photos of my work that I did not see in the workshop! The link I posted when I first mentioned casting the whole thing all look acceptable as nameplates and not a lot different to that red and black infilled one of yours. The paint hides the cast or machined surface so harder to tell the method used

Would sae660 do? No idea if it's available as plate

The foundries I've used unless requested otherwise use a sand called Petrobond which takes very fine detail. Here's a wooden pattern I made and the casting that resulted.

I did paint the pattern, but the actual finish was as you see here. The resultant casting:

The Capital letters have the squared edge from the pattern and the script letters are rounded as per the pattern. If you CNC'd the letters on your pattern with a consistent draft you would get something cleaner and crisper than this.

Edited By Stueeee on 11/02/2022 16:09:06

What sort of size is that?

I once met the lad who started Prop Shop, he made lost wax bronze props that came came out of the mould much like that .

His secret was the stuff he first dipped the wax blank into, gave a very fine finish and looked like white toothpaste when wet.

14" across. I do quite a lot of 'model engineering' at a scale of 12" to the foot but the small castings I have had done where the foundry has used Petrobond sand could almost be mistaken for die castings. Sometimes when I'm getting a casting done for an early car or motorcycle, I have asked them to use oilsand because otherwise a replacement casting just looks wrong on a 1920 something motor or whatever.

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!

It's not that it is hard but being it can easily be cold formed is softer and can be prone to grabbing a drill bit