Mould making

[benniejordaan]

Following a thread in the Saltwater section, I decided to take pictures as I go along making a new 10 Oz sinker mould. I made my first mould because I felt that I need something different. It could be used to make spoons or jigs and jig heads... The list goes on.

Anyway here goes.
Making sinker moulds…
 Step 1
First step is to make sure the sinker or what ever it is you want to make castings of is clean and has no sharp or uneven edges. If you are using a sinker, the best is to us a file and then rub it with a smooth object. Here I used the side of a screwdriver. This will prevent the sinker its self from damaging YOUR casting when trying to remove it.

 

[benniejordaan]

Step 2
Lubricate the sinker with Vaseline before moving on. Mix some Plaster of paris to a fairly thick consistency and pour it into the mould. Then gently shake it to spread it evenly. While it is still wet, press the sinker into the mould. Allow the plaster to set for approximately 5-10 minutes.

 

[benniejordaan]

Step 3
Remove the sinker and using a counter-sinking tool, drill some holes around the mould. It is important to make the holes tapered or the mould will get stuck when you try to split the mould.

 

[benniejordaan]

Step 4
Reinsert the sinker and spread a light film of Vaseline over the face of the mould and the sinker. Make sure you spread it generously on the edges between the plaster and the container and as well as inside the holes you drilled. It is important to get every bit of exposed surface.

 

[benniejordaan]

Step 5
Now mix a second batch of plaster and pour this over the first moulding and sinker. Fill only to ensure you have about 5mm over the sinker. Any more is a waste and will just cost more money. Gently shake it to try and remove as many air bubbles as possible as well as spread it evenly.

 

[benniejordaan]

Step 6
Allow the plaster to set for about 15-20 min, then remove both from the mould/container and place it in an over at 80 degrees for about 1 hour. The heat will cause the sinker inside to expand which will split the mould. Here it is ready to go into the oven...

 

[benniejordaan]

Step 7
Remove the plaster mould from the oven and allow it to cool to a manageable temperature. Now you can remove the sinker and drill holes where needed for filling. The mould, also known as a pattern is now ready for casting (to be done by a foundry). In Durban you can use Aluweld who have confirmed the price of R85 (up to 1 kg). This mould would be about 500g.

 

[benniejordaan]

Notes:
The container you use should be just big enough for the job. If you want to make a multi sinker mould you only need about 5mm between the sinkers and 5mm at the top and bottom. Any plastic container can be used. Here I used a tray from a bolt sorting system.

In total it took me 30 min to make excluding the 1 hour baking time!

I will post pictures of the final mould and a sinker soon.

Cheers
Bennie

 

[BigMatt]

brilliant post. thanks so much, never tried this before!

 

[benniejordaan]

Thanks BM,
I will send the pattern for casting tomorrow and should have it back by Thursday/Friday. Will post pictures of the final product.

Here it is with the filling spout in place.

Tight lines!

 

[benniejordaan]

So this morning I got the mould... here it is!

 

[benniejordaan]

Hold the mould in a vice and pour moulten lead!

 

[benniejordaan]

2

 

[benniejordaan]

3
Note the mould here looks very shiny... It is because I brushed it with a fine wire brush before casting!

 

[benniejordaan]

Easy hey and the total cost was under R100.

 

[Andre Laas]

Great Stuff Bennie!!!!

 

[Kumz]

Nice one Bennie

 

[benniejordaan]

Thanks guys.
Here is a contact of a foundry in JHB.
Holden Castings CC
Address:
40 marlborough rd
springfield
johannesburg
2197

011 6836300

Speak to Richard! He will help you out. He does already make a number of moulds so worth checking it out!


Cheers
Bennie

 

[tauruck]

benniejordaan wrote:

Thanks guys.
Here is a contact of a foundry in JHB.
Holden Castings CC
Address:
40 marlborough rd
springfield
johannesburg
2197

011 6836300

Speak to Richard! He will help you out. He does already make a number of moulds so worth checking it out!


Cheers
Bennie

I grew up about 500m from that place in Springfield. Thanks.

 

[Homie]

Mickey,
Where is springfield in gp ?? Is this near you in Buccleuch ?