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View Full Version : Good Vibrations....for CASTING???



BruceB
06-06-2006, 06:59 PM
No, don't head for the sex-toys-and-rubber-goods-store.

On occasion I've found that agitating the mould a bit as it fills has helped in getting good fill-out. Just a minor, gentle to-and-fro shake seemed to help a bit.

So today, having some time to think while casting some .404s with my new NEI mould, and running into minor difficulty with rounded bases on some casts, I started cogitating about maybe rigging up a sort of vibrating surface to rest the mould on while it's being filled. The aim is to agitate the liquid alloy so it fills all the corners in the cavity a little more effectively.

All I could find in my shed for vibrators was my electric "engraving pencil", but I opened up a large-ish hoseclamp (thanks, Buckshot) and with that and a couple sheet-metal screws, fastened the engraver to the underside of a 6"x 8" piece of 1/4" aluminum plate that was kicking around. The aluminum was then made into a sort of "bridge" by mounting it between two wooden blocks with the engraver underneath. The whole Rube Goldberg rig was then placed under the furnace spout.

I turned the pencil on at a medium setting (DAMN, but that's an annoying buzz!!) and commenced casting again. Naturally, the jury-rigged vibrator assembly wanted to boogey all over the bench, but in spite of that........

I'll be jiggered if it didn't work! Prior to this wild-eyed idea, I was getting a slightly round-based boolit about every six or eight casts. Filling with the mould vibrating, I got almost NONE!

I suspect it wouldn't take much vibration to do this job. I was wondering where I could find a SILENT vibrator machine...even as small as the ones in cellphones...that could stand being run for hours on end. NO, not from the stores referred to in the opening line! One of those electric "palm" type massagers? Something else?

Any bright ideas?

OK, carpetman...you're onstage...take it away!!

hiram
06-06-2006, 07:23 PM
How about using 2 hose clamps and clamping the engraver directly onto one of the mold handles. You would have good vibrations without the jitterbug.

LET-CA
06-06-2006, 07:34 PM
A small aquarium pump is very quiet and vibrates well too. Cost about $8 if you've got a WalMart nearby. Good luck

redneckdan
06-06-2006, 07:52 PM
theres an electrical supply house on line that sells pager vibraters. all they are is a little motor with an off center weight on them.

Haywire Haywood
06-06-2006, 08:22 PM
a little motor with an off center weight on them.

That's exactly what those oblong things he's talking about in the first post operate on..... don't ask me how I know. [smilie=1:

Ian

trk
06-06-2006, 09:34 PM
Of course if you want to do it with industrial quality, there are AIR powered vibrators!

trk
06-06-2006, 09:40 PM
There are quite a variety of motors that are built as devices for vibrating things - for example the tumblers for cleaning brass, a device called a 'jogger' for straightening up stacks of paper and others.

Hence, motors that have the counter-weights built in are commonly available. With regard to the noise, the larger motors aren't as obnoxious as the engravers are.

Pawpaw
06-06-2006, 09:50 PM
I find that new molds don't want fill properly. This is that new NEI mold you're talking about, right? GIve it a chance to break in and it'll be fine.

David R
06-06-2006, 10:33 PM
Hairclippers? $5.99 at wally world on sale. They even have an adjustment for the amount of "buzz".

Bucks Owin
06-06-2006, 10:51 PM
Of course if you want to do it with industrial quality, there are AIR powered vibrators!

How about diesel...Any diesel powered vibrators?

Ah, never mind :roll:

Dennis :-D

wills
06-06-2006, 10:53 PM
Like this?

http://www.isr.umd.edu/ISR/accomplishments/044_VibratoryLinearMotor/fig1a.jpg

Bucks Owin
06-07-2006, 10:38 AM
Actually, I bet a vibrator of some kind works good. I've tried tapping on the handle tongs before the sprue hardens to get a better "fill". Seems to help sometimes....

FWIW,

Dennis

HiWayMan
06-07-2006, 10:54 AM
UH.................in all honesty your best bet for a quieter vibrating unit may well be that "sex-toys-and-rubber-goods-store". After all they are designed to be quiet and powerful. They run a long time on batteries so no additional power cord needed.




..............I feel like such a perv now..............

Bucks Owin
06-07-2006, 11:04 AM
..............I feel like such a perv now..............



As well you should! [smilie=1:

Dennis :-D

(Maybe like a different "handle" for the mold blocks you mean?)

Ack! Now ya got me doin' it! LOL

Bass Ackward
06-07-2006, 03:14 PM
Bruce,

Unles you have your heart set on finding a solution, Why not just improve the venting on the top of the blocks first and see if that cures the problem. Use a small bevel on the top of the blocks. If you can't win fair in life, .... cheat.

uscra112
06-10-2006, 11:52 PM
The vibrator on a cell-phone is just a tiny motor with an eccentric weight on the shaft. Any small motor bolted to the underside of that plate, with some kind of off-center flywheel on the shaft, will do just fine. My thought would be to get a "400" DC motor at the local model airplane shop. Ten bucks or so. It will want a 6v supply at about 0.7 amp., which a lot of standard wall-wart power supplies will provide. While you're at it, get a "prop adaptor" to go on the shaft. Get a steel fender washer with the hole a bit oversize for the prop adaptor, put it together with the washer offset by about 1/8", and mount to your plate.

I'm gonna try this!

njmj
06-11-2006, 03:30 PM
How about getting a foot switch so you can just step on the pedal for the vibrator when you need it? NJMJ

Blackwater
06-12-2006, 10:43 PM
Bruce, I once had that happen, using a new Lee mould, but after Lee-menting it, it was no longer necessary. Kept me from having to stop and do the Lee-menting right then, though, and I needed some good bullets. Sometimes, time is the driving force, but I'm bettin' the suggestion about the vents will likely tone down the noise for you without getting bad bullets.