Pouring day

Hi Pete,

Thanks for your input. I agree, Id like to try that as well, my issue is how to vent or use the riser in a way that it doesn't touch the finished surfaces. The only way I could see it is with two risers on the outside of each rail at the tallest point.

Here are 2 quick ideas, still not sure. Doing some reading. You get the idea though.

Thanks,
William

 

I like to keep everything simple, the KISS principle.
Your part is small enough that vents are not needed.
Spin traps...never used one and probably never will.
Keep mulling your sand, it looks too loosely bound.
Risers, those thick sections definitely need one on each. The risers have to be larger than the section it feeds. They will be the last to fill and the last to solidify. Make your risers open top so you can see when they fill.
I'm not a fan of having multiple metal fronts entering the mold so I would try gating into one of the legs first. If the metal freezes before it gets to the far leg then go ahead and split the flow into the other leg.



This is how I mold the sprue-runner. A smooth transition at the base of the sprue and a tapered end on the runner.

 

Good morning FishBonzWV,

This was not what I expected, but very exciting. I can make the riser cones in a way that are notched to sit flat against the outside to the body so the upper portion stays circular, if that matters.

What size should the runner be: 3/8"x 3/8" ?

I wasn't sure about the dotted runner on the upper part of the image you created so I went with the one runner, I added a vent on the lone pad as well.

I think you are correct on the rammed sand, need to be sure it's done better.

As I reread your comment, I need to make those. risers even bigger. The rails are 9/16" wide by 1" tall.

Thanks so much,

William

 

Probably 1 1/4" - 1 1/2" at the top.

1/2" x 1/2" .

That is the alternate in case the first try doesn't fill.
Forget the vent.

Here's a couple of my short runners that I use to mold them in. The blind hole is where I stick the sprue in.

 

Thanks for that, so helpful. I'll be trying this today or tomorrow. This will be interesting, BTW my flasks are 4" deep so I think there will be ample head pressure.

Stay tuned and thanks again Fish!

William

 

Got my parts made up.

 

Alrighty,

Pour #3, Bottom fill. I'll let the images speak for themselves.

 

Good to see you got a complete fill.
Critique:
Pour faster, the spue should be full when pouring. That one was sucking in air.
The last photo showing the bottom, sand wash at the far ends of the mold. You can add small "risers" at the very ends to let the sand flow into them. They would really be trash tubes.
I think your sand was too wet and you got steam pox on the top. The thick sections were hit hard. The riser tops look clean without the pox because the was no sand on them.
Move your runner over so the end of it goes past the toe that you are gating into. If there is any wash it goes to the end of the runner.
It's getting better.

 

Thanks for the great advise.

I think I went slow so that the bowl didn't overflow too much. I'll plan another pour and see if it gets better after adding your recommendations.



Thanks,
William

 

Thanks Jeff,

I have seen his video but will def make it deeper next time.

Thanks
William

 

Hey fellas,

Did another pour today with my KBond recipe using Organlclay, 140 mesh/80 mesh, 2 stroke oil and IsoAl.
I am getting much closer and doing the bottom feed is def the way to go. I really need to be more careful with the ramming as well, I made a match plate too, which made things so much easier. I also used 3000 Graphite powder on the part and surface and that helps I think.

Ive watched a few of Andrew Martins video on YouTube as well. Thats why you see the blind riser.

Feel free to advise, critique, high 5's whatever. LOL

The detail is very good yet the taller rails have voids, could be due to the 1/8" whistle vents.

@FishbonzWV

Cheers,
William

 

Wow!
Much improved surface finish with the oil bonded sand. Now you need to get back to the large risers on the thick sections and I don't think the vent is needed on the little button. What's that button called and it's use?
Matchplates make molding so much easier...good job.

 

Thank you very much,

Yes a big improvement. That button is where a spring will go, I call it the spring pad. Heres a Bigsby tremolo for reference.
I'll be increasing the risers for sure, I just wanted to see what the vents would do.
This week I should have it nailed down. So happy with the progress.
Loving the match plate too. so much easier. I was watching Andrew Martins videos on that. Plus he incorporates that blind riser, which I added.

The risers should be easy enough to clean up, since they are centred over 2 valleys, a round file should do the trick.

Thanks for your advise. So valuable, both you and @Tobho Mott and @HT1

 

I like to keep things as simple as possible. Every change of direction and every intersection of metal flow has the possibility of causing turbulence and sand wash. If it was mine, I would sprue into one of the ends of the long runner and dispense with the T intersection and the blind riser. Slope the end of the long runner so the metal has a smooth flow and taper the other end of the runner to prevent bounce back when the metal hits the far end. Get rid of the vent on the button. KISS

 

Ok new strategy,

I moved the gating to the thicker end. Definitely a better approach. Everything filled perfectly and all detail intact. Woohoo!

Now I will trim the gating a bit since it went into the part more than I wished, still a success!

Oh and this was all 80 mesh with some 140 mixed in from the earlier pours.

Now to address porosity. hmm Mind you I have been using the same aluminum for all these test pours so to be fair, I am sure ive added more hydrogen at each pour.

 

Poured the control arms for my tremolo. Just starting to do the finishing, it'll be getting inlays to dress it up. I setup the match plate to pour two at a time.
I used a spinner setup and it worked very well.

Cheers,

William