Casting Engine Components For a Twin

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As you have guessed, got it hot and poured quickly, no other tricks... 8)
 
Artie
May I say what s fine job you are making of your engine. Being a home foundry man I know the fun that can be had from producing your own patterns and castings.


I hope you don’t me mind adding my bit to your thread.
The problem of a dropout (where the sand drops out of the moulding box) usually when you are closing the flask (moulding box) for the last time, ready for the pour. Is always there when using green sand moulding. Many of the commercial foundries use air set (a resin-bonded sand that goes off like mortar). And they can handle the flask a bit more roughly.
I use a moulding box with two rods through the top box, which help hold the sand.
Feeding large flat thin castings can be a problem. I was told by a foundry man to try a fish tail feed. Which I have found dose seem to work, by spreading the amount of molten metal entering the sand cavity.
Keep up the good work
Dave Bick U.k.


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You can also try 2 or 3% of portland cement in your sand for those tricky ones (moisten it with that Southwark beer - it must be good for something)
 
Hi Dave, mate please jump into this thread whenever you feel you wish.. and take it into any directions you wish.... ;D
The input is ALWAYS welcome.

I used timber stays in the drag and a casting board under the cope... I think I eluded to the fact that there is the correct way and then the way I used .. :big: Ive never cast a unit this size in a closed mold before (open mold yes..) and doubt that I ever will again... but, it did work after a lot of mucking around....

Howdy Tel, I guess the cement would make the sand a 1 use event, would be worth it though.. and for the record...I used YOUR clay in this one... thanks again mate.... and THAT beer would definatley not be good for this... it aint good fer nuffin.... :-

Today I used the flycutter to flatten and pretty the working surfaces... firstly the back of the plate....

24112010312.jpg


And the mounting surface....

24112010311.jpg


I added a little putty to a couple of spots.. those areas Ive already discussed as not pleasing me greatly....

24112010313.jpg


and roughly how it will sit... boiler will be up so its top is just under the crank centre line.

24112010315.jpg


No real inclusions to speak of, a good solid cast... machining them up is alweays the test.. they all look good until you cut open the voids etc..

Cheers all...

Rob T
 
Really starting to look the part now
 
Looking good Artie. This is going to be an impressive paddle steamer when you are done.
I've been promising the kids we could go on a paddle steamer one day...
I wonder if the PS Melbourne is running while the river is up? I think the Ruby is taking passengers now too.

I'll have to investigate.

Cheers,

Nickle
 
Can it really have been so long since I posted on this project???

Just a small update, the engine is still happening, Im just taking a break for a while, its been fairly intense for a long time and I needed to concentrate on other 'stuff' for a bit and also christmas got in the way..

Work has been hectic and the office on the coast now requires me for 2 weeks out of every month, so I only have a small window of opportunity from now on. Other projects have gotten in the way as well such as I needed to freshen up the Duke, it was last restored over 10 years ago and the paint was getting a bit tired and I came across a TT style tank for her... a coupel of pics if you are interested....

Here... http://madmodder.net/index.php?topic=4318.msg45589;boardseen#new

Cheers all

Rob
 
Can it really have been so long since I posted on this project???

Yes it can - I was beginnin' to think you were in gaol!
 
Ahhhh Jeff, dont hold your breath.... particualrly now that new demands are placed on my availability... BUT..I do have a lead on a filing machine...... looks good..... ;D
 

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