Ok so I have decided to start a new thread with what I am up too.
As I was off Friday 4/11/16 I decided to start the weekend with a random cast of a small pumpkin!
I was planning other things so I didn't spend much time with this, a better gating system would have worked better (I need a horn lower feed pattern).
I jacked up the drag a little and ramed up, fliped it and coped down:
Then I smoothed out:
And pulled to check my parting was as good as i could get it, as it turned out I was a wee bit too low, so had to backfill:
Happy I dusted and rammed up the cope putting a small sprue stright in the top (yes yes I know, like I said time):
Now The reason I was casting was a christmass present:
I had a bit of a problem here, the patern has warped slightly and i think it must have been rocking as I ramed it up, result was I had to touch it up slighly prior to casting:
The result was marks in the cast, I wil just have to do it again is all:
As for the pumpkin, not too bad considering I was messing around and it had a crude gate (if you can call it a gate):
Sat 5/11/16, decided I had to try having a go at direct melt (and I'm not doing that again unless I'm desperate) the Aluminum keeps freezing as it came out of the spout. Ironically after 2 tours of messing around scraping it out through the spout I decided enough was enough, so had a stir around in the bottom of the crap to get the last dregs out and I moved a cast iron plough tip I had placed in the furnace bottom to divert the flame (my drain is directly opposite the tuyere), this started pusshing a little flame out of the drain, helping keep it flowing!!!
The result was this lot:
Yet to see the devistation inside
Last edited by wargrade; 11-08-2016 at 07:22 AM.
It was not as bad as I had feared, It broke up real easy & left no trace after removal.
The plough tip I put in to deflect the burner jet from the drain didn't fair so well, in-fact about 1/3rd the way through the melt, there was an almighty bang.
I put it down to one of the parts I was melting having a water pocket (despite heating them through thoroughly), however I think it was the plough tip exploding as there's a fair chunk missing off the back.
Where that has gone only knows as there was no trace of it in the rubbish!
I'm glad to see the furnace cleaned up easily. There's 2 ways I've been successful with direct melts: either building up a reservoir of molten metal and releasing it all at the same time, or when dribbling metal out, making sure that the spout always has plenty of heat. Anytime I have relented on the heat for even a moment it backs right up.
Is it possible someone can correct my threads title typo please?
so far this weekend, I have still been sorting out my oil heating system as my glow plug heater sprung a leak (bloody oil).
Redoing it, I will add photo's later.
I also have been getting a wee bit fed up worrying about sand spilling off my bench on to the floor, lets face it, ramming up is not the tidiest thing to do unless you do it very carefully.
despite my best efforts though I still get some on the floor:
I decided I needed a way to stop it, the simplest way is to put a edge around it, but this I wanted removable (you know as soon as you fix anything something will change).
So I set about cutting some skirting board for the aforementioned uses of and found some bolts to use a pegs, lucky I still had enough Audi airbag bolts kicking around that fitted the job nicely.
These are an M6 thread. Having used normal threads in wood before I knew this would not be a problem, drill a hole just as you would if you were going to tap it, then just screw it in, it will hold real tight.
I first drilled the holes in the top, fitted the bolts then used them to impress on the wood, thus perfectly marking my drill hole:
Once assembled I have a nice little sand pen:
That done, I decided to make a long over due rammer. the pattern is simple enough, a bit long but I felt this was would be handy rather than a hindrance:
This made me thinking even more about casting small little christmass presents for my family.
Like Your working table, everything seem to be on the right place. I'm still working on the floor, but will get to that point soon.
What kind of coating has the rammer on both sides ? Makes me wondering since mine have a problem with sand sticking to the flat end.
Hoot, I use what is left of an automotive spray paint, It's metallic and gives a nice finish.
I use it more to seal the pattern than anything else, as it's so runny it gets soaked up quick but on the flip side it drys very fast too.
Once dry I spray it with automotive clear coat lacquer, again it dry's quick and this gives a smooth shiny finish.
For all the issues i hear people having with direct melting via their drain, I'm going to apply the odds and say i must have done something wrong when constructing my furnace. Now I've only direct melted once but my furnace was nowhere near normal operating temp when doing so. In fact i had the lid open a good portion of the time. I just let it break down as it wanted to and let it slowly drip out the bottom into my ingot molds. Ended up being a big blob of aluminum afterward but easier to manage and free of heating coils.
JV at the end it seemed to be working well, but by that time the panic had been going on too long so it was just relief more than anything.
I have plenty to be getting on with, I won't rule out doing it again but I will do what I can to avoid it.
So had a look at the results of the weekend, out of the 4 planed, I didn't have time for the rammer, one cast I knew was good, one failed (molten metal escaped from the side) but remarkably this was a 98% so good enough. and the last one for a christmas present well: