PDA

View Full Version : Casting Tools Part 4 - Sand Casting Tools



RayG
10th Nov 2011, 09:06 PM
Hi All,

Just a quick overview of some of the tools used to prepare sand molds for casting, I'll leave patterns and cores for next time, these are just the tools used to do the preparation for the pour.

First, I recommend petrobond for home hobby casting, it's an oil bonded sand, rather than "green sand" which is a water bonded sand. It's re-usable many times, and a bucket will last just about forever for home use. I got it from CMS, but I've since found they have changed names, I think they are now called "Arnott & Guy Foundry Supplies" 20-22 Marni St, DANDENONG SOUTH, VIC, 3175.

http://www.backsaw.net/pics/Casting/DSCN0962.JPG

The Queensland Address on the pail might still be the same..

The consistency can change over time, and might require a touch extra oil, or sometimes I've added a squirt of iso-propanol, what you are looking for is when you grab a handfull, it packs cleanly and holds together nicely..

http://www.backsaw.net/pics/Casting/DSCN0963.JPG

Here is a quick overview of some of the tools used...

http://www.backsaw.net/pics/Casting/DSCN0961.JPG

Riddle (sieve) for removing clumps, scoops, rammers, scrapers, tubes for cutting sprues and risers, wire for making vent holes, trowell for cutting gates and parting lines, the sock is full of parting compound for dusting the pattern as well as the parting line in the cope and drag. The two screws are used to help remove split patterns from the sand. Also I'm told talcum powder works fine as a parting compound.

http://www.backsaw.net/pics/Casting/DSCN0966.JPG

The cope and drag, the drag is the bottom, and the cope is the top, together they are sometimes called a flask.. some flasks have snap connections on the corners. It's important that the cope and drag register accurately, that's what the triangle shaped bits on the side are for.

http://www.backsaw.net/pics/Casting/DSCN0967.JPG

Showing the two parts seperated..

http://www.backsaw.net/pics/Casting/DSCN0968.JPG

The best book for sand casting techniques, is CW Ammen, he covers patterns and casting strategies in some detail, the other is the Stephen Chastain book, which covers just about everything, but is a bit light on the casting strategy stuff..

I'd recommend you get both.

The next installment (part 5) will be making a pattern and preparing the cope and drag for casting.. that will demonstrate the use of the tools above...

Regards
Ray

eskimo
11th Nov 2011, 09:33 AM
Have'nt you got any thing to do Ray

its great stuff :2tsup:

I hope your saving all of this in word or something..It'd be great to see it as a pdf or similar after all the chapters are finished?

PS dont forget the chapter on SAFETY

Bryan
11th Nov 2011, 08:54 PM
Onya Ray. Don't think for a moment no replies means no interest. I've got my ears pinned back! And I'm sure many others do as well.

Steamwhisperer
11th Nov 2011, 10:19 PM
What Bryan said Ray

Phil

WillyInBris
13th Nov 2011, 09:26 AM
I would just like to thank you for this Ray it may be something I never get to do but I find it very interesting indeed.

19brendan81
8th Dec 2011, 04:39 PM
Ray what do you do with the black, charred bits of petrobond after you have cast in it? I try to discard that bit, but by the looks of your photo theres a fair bit of black in that sand....do you just put the lot back in?

RayG
8th Dec 2011, 06:01 PM
Ray what do you do with the black, charred bits of petrobond after you have cast in it? I try to discard that bit, but by the looks of your photo theres a fair bit of black in that sand....do you just put the lot back in?

Hi Brendan,

I used to do just that, scrape off the charred bits, and still do if it's a large lump that's easy to pick out, but over time more oil gets burnt off, and I add a bit of extra oil (doesn't take much) also a spritz with propanol seems to help keep the right consistency.

So, by all means keep as much out as you can, but I don't think it's a deal breaker.

Regard
Ray

eskimo
9th Dec 2011, 10:08 AM
cant wait till this comes out in book form...need it for my library

19brendan81
9th Dec 2011, 12:03 PM
Thanks Ray