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Four stroke Fred10/06/2022 09:17:50
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291 forum posts
284 photos

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A Smith10/06/2022 11:44:05
85 forum posts
4 photos

Following with great interest.

Andy

Four stroke Fred22/06/2022 09:56:56
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291 forum posts
284 photos

I have just checked back on this forum and discovered that I have been working on this casting for the engine for about ten months ! The last few weeks have seen a repeat of the processes that I carried out except this time I am using new patterns and core boxes. There is no substitute for experience as long as it it a learning process. The photographs show the latest attempt with modified runners and risers. Tomorrow I hope to pack the top half and next week attempt pour number three! This time I am using a finer facing sand and this leaves a crisper finish to the mould. Photo to follow.

Fred.


Four stroke Fred22/06/2022 10:04:32
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291 forum posts
284 photos

cf23f624-bb06-4e28-bd0d-9d463d0ebf23.jpegFred.dcb140bb-0ef9-4281-bf17-144a6eeb5ccf.jpeg

Adrian R222/06/2022 14:18:59
164 forum posts
5 photos

I may have mentioned this before but have you come across a Youtube channel called "Olfoundryman" in your research? He is, I think, a retired professional foundry worker who up until some recent poor health was still casting in his home workshop and producing high quality work. I have tried to copy his advice on pouring basins and runners in my own poor attempts. A recent video titled "possibilities" includes some recommend reading, e.g. Dr John Campbell.

Four stroke Fred26/06/2022 03:31:48
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291 forum posts
284 photos

58804087-dfa4-4a52-be2a-379edec120fd.jpegIToday I assembled the blocks ready for casting next week, weather permitting. The top photo shows the three cores in position with the water passage core held in place by the chaplets - sample shown in front right hand corner. This was a real fiddle and a test of will power! All the blocks have been glued together and vents cut into the top blocks to release any gas build up from inside. It seems almost a pity to pour metal in but the aim is to produce a good casting and hope that this is the last time. With this part of the project it makes me feel almost like a child who leaves his home work to the last minute ( having completed most of the other parts already) but you know it has to be done!

Fred

Four stroke Fred29/06/2022 07:56:34
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291 forum posts
284 photos

After many months of trying to produce a good casting, today was the day. The photographs show the cleaned up engine casting with all the runners, risers etc. The quality of the casting ,particularly the surface finish both inside and out has improved over the other two attempts and pouring method worked very well. The rectangular block is the pouring basin and it was a pleasure the see the molten metal being drawn into the mould and the rise up the vents. Fortunately the sand core for the water passage did stay in place and with the sand now removed it looks good. One could say the cloud has been lifted! The next stage is to trim off the parts not required and prepare the casting for machining.

A very happy,
Fred.

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lee webster29/06/2022 08:16:39
116 forum posts
10 photos

Hi Fred,

This is the first time I have seen this thread, so I hope I am not asking questions you might have already answered.

1) What sand system did you make the cores and mould with? It looks like some kind of bound sand, resin?

2) What metal did you use for the pour?

3) Not a question, fantastic job! Such a nice casting.

I am nearly ready to produce the moulds for my, what started out as half scale but is now third scale, Austin Seven engine. I have 3D printed the crankcase just to have a look at in the flesh and decide the best way to produce the patterns. I started to realise that a two piece pattern might not do it, I might need a four piece. I didn't think I could do that with green sand, it would have to be a resin bound sand. And then I come across this thread with a four piece mould. Talk about perfect timing!

Lee

Four stroke Fred29/06/2022 08:40:38
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291 forum posts
284 photos

I it took me a while to find the second photo but here it is. Thanks for your comments Lee and to answer your questions. I use a resin bonded sand ( with hardener) for both the cores and the “blocks” and use “ Liquid Nails” to join them all together. The sand used on the surface of the casting is quite fine but I back it with a courser mixture. The ratio I use is 1kg of sand ,25cc of resin and 2.5cc of hardener. The resin needs to be well mixed into the sand and contrary to information that I have read I then add the hardener. You do not have a long time to play with it ! I make sure the mould is well vented and as you can see I use a reservoir to pour into. The casting is in aluminium - melted down Lister diesel pistons and degassed. I was interested in your new project of the Austin 7 engine. This brought back many memories as that was my dads first car when we lived in North Wiltshire - ah those were the days! I hope all goes well and would be interested in the outcome.

Fred.

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Hopper29/06/2022 08:49:17
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6694 forum posts
347 photos

Awesome work Fred. You got there in the end. Worth all the work by the look of it too.

Four stroke Fred29/06/2022 08:58:09
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291 forum posts
284 photos

P.S. I forgot to add a big thanks to my mates Ray, John and John whose help made this possible. We are only a small group of vintage years who share our interests and enjoy our hobby.

Fred.

Roger B29/06/2022 10:00:19
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192 forum posts
82 photos

That looks good smiley

lee webster29/06/2022 11:58:57
116 forum posts
10 photos

Thanks for the information Fred. I see that you are in Australia. I wonder if what you call "liquid nails" is what we here in the UK use to stick timber and panels to walls etc?

I have a long way to go with the A7 engine. It's my first attempt at anything like this.

Lee

Four stroke Fred29/06/2022 12:31:17
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291 forum posts
284 photos

Lee that sounds to be very similar to our Liquid Nails. It has a rubbery texture with plenty of body and sticks to your fingers very well! Accept the A 7 engine as a self inflicted challenge! The use of a 3D printer to prototype parts is very useful and tactile as they can high light problems with the design that you may not at first see. I have been working on this casting for about the last ten months and the 3D prints were used as both patterns and core boxes. Having the use of this type of technology (CAD and 3D printing) does make life easier.

Fred.

lee webster29/06/2022 14:29:33
116 forum posts
10 photos

I am surprised that the liquid nails withstands the heat of the pour. Do you use water based or spirit based?

If I can't make a greensand mould, the pattern has some small details that might not survive the extraction of the pettern from the mould, I have some epoxy resin bought from a local boat chandler.

A new resin 3D printer is on it's way. I hope to get prints from it that need less preparation than those from my Ender3. A good printer, but it has its limitations.

Lee

Howard Lewis29/06/2022 17:14:34
6314 forum posts
15 photos

ABSOLUTELY fantastic!

I stand in awe of your persistence and skill

Persistence pays off

Howard

DiogenesII29/06/2022 17:29:55
589 forum posts
234 photos

Looking very good indeed, Fred..

Four stroke Fred29/06/2022 22:04:36
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291 forum posts
284 photos

Lee, Liquid Nails must be a spirit based glue as washing the hands in water does not remove it. When using it to glue the blocks together I keep it away from the edges of the joint that are exposed to the molten metal. This leaves a small flashing on the casting but that is easily removed later. I do seal the outside of the joints just in case there is any small leaks. I also use an Ender printer with a working volume of 250x250x250 and work in both PLA and ABS.

Fred.

lee webster29/06/2022 22:53:48
116 forum posts
10 photos

That is a lot of useful information, Thanks Fred!

Lee

Hopper30/06/2022 03:15:22
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6694 forum posts
347 photos

If you Google "Liquid Nails MSDS" you can download the list of ingredients. For some reason it wont let me cut and past the list onto this site.

Basically a solvent-based high-strength construction adhesive.

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