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Lucie
13-05-2014, 12:45 PM
Hi All, I've had a quick hunt through the old posts & can't find an answer - I assume this is because there isn't one, but just in case.....

Is there any way fill in small holes in cast pieces, without having to send them off to be lasered?

Thanks :)

medusa
13-05-2014, 01:00 PM
I'd like to know if there is a way to have larger holes filled as well. My caster 'helpfully' suggested filling with solder. ~facepalm~

ps_bond
13-05-2014, 01:01 PM
A rotary burnisher might help with some, you might be able to fill them with solder (eww).

Lucie
13-05-2014, 01:15 PM
It's only one little hole but it seems a shame to leave it. I'm way too much of a perfectionist ;) I usually solder with hard solder paste (hangs head). Do you think that would do it?

Lucie
13-05-2014, 01:27 PM
I'd like to know if there is a way to have larger holes filled as well. My caster 'helpfully' suggested filling with solder. ~facepalm~
Think I might know who you mean lol. I'm getting on great with Just Castings but I'm still having issues with hidden bubbles in my waxes. Going to do a bit of experimenting. I'll let you know how I get on :)

ps_bond
13-05-2014, 01:30 PM
If you need help on the porosity, feel free to give me a shout.

medusa
13-05-2014, 02:11 PM
Think I might know who you mean lol. I'm getting on great with Just Castings but I'm still having issues with hidden bubbles in my waxes. Going to do a bit of experimenting. I'll let you know how I get on :)

I have one useless casting still (useless because it has holes all over the inside and they put a huge big sprue on the outside) and I am owed for two large bangles which I returned because rather than sprue-ing on the original (enormous) sprues they asked me to leave on in order to make the moulds, they decided to sprue in another place, again on the front. I'm leaving it until after I've submitted my thesis. It was just too much hassle and distraction, but i was really happy with the service from Niagra Falls.

CJ57
13-05-2014, 05:06 PM
What about soldering in a piece of wire and filing it down if that's possible

Lucie
13-05-2014, 05:12 PM
What about soldering in a piece of wire and filing it down if that's possible

Thanks Caroline, that's a really good idea. Think you might have solved the problem (yay).
Now just got to solve the mystery of how to stop the bubbles in the first place.

Lucie
13-05-2014, 05:12 PM
If you need help on the porosity, feel free to give me a shout.

Sent you a message Peter :)

Dennis
13-05-2014, 08:08 PM
Lucy, I don't really see how voids in your wax, provided they are below the surface, can be translated in your castings. If castings come back with bubbles it is the fault of your caster. They can avoid them by using a vibrator when investing, or by using a vacuum pump.

If they are blaming you, go elsewhere. Dennis.

ps_bond
13-05-2014, 08:40 PM
I'd agree - if the surface of the wax is clean, then the investment should conform to that. The wax could look like an Aero internally and it wouldn't make a difference.

I did mean I can help fix porosity in the cast rather than in the wax I'm afraid! And not with solder.

Lucie
13-05-2014, 09:23 PM
The surface of my waxes are completely perfect - quite literally filled and polished. I'm now on my 4th caster & have had the problem for years now. Approximately 50% of all castings have hairline cracks. I get around it by making duplicates but its a huge waste of time. I was told today that during casting the vacuum can draw bubbles to the surface. Is this complete nonsense then?

Dennis
13-05-2014, 10:01 PM
Well Lucy, they are not bubbles from your wax, because that burns out completely, leaving an empty mould. If bubbles occur it is due to gases in the molten metal, so causing holes or porosity.

Actually my post above is nonsense too, because holes in the investment would cause small beads on the casting. However, you would be wise to go on searching for a better caster. I have used West One Castings in Hatton Garden, and so have other members, so you might try there. http://www.londononline.co.uk/profiles/181879/ Dennis.

medusa
14-05-2014, 01:21 PM
I did mean I can help fix porosity in the cast rather than in the wax I'm afraid! And not with solder.

can you elucidate?

ps_bond
14-05-2014, 01:46 PM
Laser... I've had quite a lot of practice fixing castings recently.

Lucie
14-05-2014, 02:00 PM
Do you have a price list Peter or do you not generally repair for others?

ps_bond
14-05-2014, 03:12 PM
It depends on the complexity of the job - boils down to how long & how much materials. It'd be daft to buy a tool like that and not take in outwork!