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shooter93
09-16-2012, 06:14 PM
While rooting through and cleaning up my makeshift loading room in hopes that for my 120th birthday I could finish it into my perfect room just off the master bedroom here I've been coming across so old paperwork,catalog, flyers etc. One is a very old set of instructions that came with a Hensley and Gibbs molds. They mention that when using their bigger molds and if you get it running to hot.....While leaving the bullets in the cavity....plunge the mold into a bucket of hot water for a couple seconds. This will help you maintain temperature of the mold. After all you've heard about water around your molten lead it sounds a little spooky doesn't it?....lol. I just found it interesting and I haven't dunked any molds yet.

Char-Gar
09-16-2012, 06:24 PM
This is a subject that will draw some different opinions. Some folks say it is the worse of all possible ideas and will warp the mould. Others say, dunk ahead.

I had a two cavity Lyman mould for the Keith designed 41 Mag bullet that overheated so bad I could not cast decent bullets with it. I tried dunking it in a can of water between casts and it cast great bullets. This is my one experience and it worked just fine and did no damage to the mould at all.

I would not hesitate to do it again, if I had problems with overheated moulds.

Our friend Bruce B came up with a method some years back that involved putting a folded cloth in a shallow dish of water. The cloth would absorb the water. Every cast the mould would be inverted and the hot spru rested on the wet cloth for a second or two. This works great, ends the wait for sprues ot harden and ends the cutting of wet sprues and leaving a smeared base. This is the way I do it now. This speeds up production and increases the quality of the bullets, at least it has for me.

runfiverun
09-16-2012, 07:54 PM
i usually have a damp rag and small bucket of water at hand when casting with my lyman 4 cav's.
sometmes i just use it on the bottom sometimes the top,and quite often i wrap the whole mold to cool it down.
i do have to remember to use a little oil on the molds when doing so or i get spots of rust on the sprue plate.
it's all about controlling the mold temp.

btroj
09-16-2012, 08:04 PM
I don't dunk, I dip the bottom edge of the mould in water. Works quick. I am now using a small fan to help keep the mould temp more consistant.

Mould temp is the key thing I try to control when casting.

fecmech
09-16-2012, 08:43 PM
When I shot silhouette and used the Lyman 429421 4 cav it was a regular casting routine for me. That baby got hot and I dunked it on a regular basis, doesn't hurt a thing imo. There certainly is no danger, the lead is under the water not water under the lead. As Ross used to say, "the devil is in the details".

casterofboolits
09-16-2012, 10:04 PM
Whjen I first started my casting business (20 plus years go) I dunked an H&G eight cavity mould on a regular basis. Still have the mould (don't have the business) and it did not warp or rust and it still makes excellent boolits.

Echo
09-16-2012, 10:27 PM
Roger on the rag soaking in water, my solution to the overheating problem. Top or bottom...

stubshaft
09-16-2012, 10:40 PM
I have and still dunk my molds for heavy weights. I have never found any problems with doing so.

WILCO
09-17-2012, 12:51 AM
Only thing I've ever dunked was an oreo cookie in some milk. Man, now I want a cookie!

shooter93
09-17-2012, 06:47 PM
I've cooled molds with a sponge or rag but it's generally not a problem for me because I use 2 molds and I'm not a speed caster it was just interesting to see it mentioned after all you heard about water and lead when you first started casting. In a set of instructions dated 1970 they also say never to put a corner of a mold into the molten lead to pre-heat it.
They also say that all molds are tested and the sample bullet sent was cast from your mold. Then there was a stamping on the sheet that said they weren't sending the samples anymore.....Because Federal Law forbids supplying sample bullets.

selmerfan
09-18-2012, 09:37 AM
I use Bruce B's method with the pan and towel. Works great, makes for CLEAN cut bases and speeds production. And I'm getting +- .5% consistency on weight sorting 215 gr. boolits.

Le Loup Solitaire
09-18-2012, 08:44 PM
This practice has been around for a long time and is mentioned in various writings by well known authors on handloading/casting. It was/is an accepted way of cooling or bringing the temperature down on overheated molds. There has never been any mention of harm done to the molds involved. It would of course not be necessary to do it if the mold is/was not allowed to overheat in the first place, but this happens particularly with large caliber bullets in a one or two cavity mold even when casting at a not so rapid pace. The first clue signaling the condition is usually the increasing length of time needed for thresprue to set/harden. Frosting of the bullet is usually present as well. There are a couple of practices to consider as an alternative to dunking, if you don't want to do it, and as a preventative measure. One is an eye on temperature and a thermometer helps. A second idea is to use a small electric fan...8" or 6 inch is adequate. A third practice is to use a second mold in tandem with the first...it keeps you busier, but affords time for the mold just filled ...time to cool and the sprue to change color and set. The idea of water in a folded piece of rag (a pad) is not a new one. The damp/moist pad was originally pressed against the sprue/top of the blocks momentarily to cool the sprue and the blocks down, If you want to do this just be careful not to get a steam burn. Setting the folded pad in a shallow water filled dish will work if you place the bottom of the blocks on it; some casters turn the blocks upside down when the sprue is no longer molten and press the sprue plate against the moist rag. These measures are necessary to prevent the loss of casting time/waiting longer for the sprue to set and avoiding smearing of lead across the tops of the blocks and the underside of the sprue plate. If the caster desires to speed up the casting process and raise production then s/he can achieve that this way. I have always preferred the use of the fan and/or using a second mold. All of my molds are iron and I have (after trying the wet pad) found the "steaming" to create not only surface rust on the molds, but I have been obliged to take the blocks off of the handles when finished and everything is cool, pull all the screws/bolts and re-oil them before storing/putting the mold up. I just don't favor the idea of a screw rusting in secret and then becoming a problem at a later date. However you wish to deal with the overheating, as long as you achieve the desired results and are satisfied then by all means enjoy your casting. LLS

bobthenailer
09-19-2012, 07:34 AM
I have tried the dunk method a few times with no problems ! ive also tried Bruce Bs method ! but i now use a small fan to cool down my moulds so the sprues can cool faster .
One thing of note those H&G gang moulds had alot more mass than current moulds so dunking would possibley have less of a warping effect if any ?

Texasflyboy
09-26-2012, 04:57 PM
I use a long steel bread pan that I got at Goodwill, lined with a terry cloth towel. Fill the pan with water until the towel is saturated.

I rest the base of Hensley & Gibbs moulds on the towel for a few seconds and then flip them over and rest on sprue plate to maintain a perfect temperature.

From time to time, at the beginning of casting, I will open the mould and clamp a wet towel and then squeeze the blocks closed against the towel. The resulting steam cleans the cavities extremely well and promotes good clean bullets.

That's how I do it.

geargnasher
09-26-2012, 06:20 PM
The only issue I've encountered with quenching moulds using the wet rag was a variance in boolits every time the mould temp is dropped. The key is frequency and moderation. I have better luck using a fan than water, it keeps things consistent with no big temp swings. I believe a lot of casters run their alloy uneccessarily hot, and this contributes to mould overheating. Some mould/boolit design combos are really prone to overheating and need frequent damp-rag quenches.

As far as dunking, I've lost more than one mould in my boolit quench bucket, and no harm done other than a screeching halt to the casting session. Sputtering and boiling water droplets/steam blows everywhere, but it don't hurt you if you wear the appropriate casting PPE.

Gear

Dale53
09-26-2012, 07:11 PM
In years past I used the water dunk method. I have been doing quantity casting for more years than I care to remember. Casting large bullets in four cavity (or more) moulds leads naturally to overheating moulds.

Some years ago, Mike Venturino mentioned using a small manicurist's fan to cool his moulds. The light went on and I immediately made a trip to the Target store and bought one for about $7.00 (look in the fan department). Wal-Mart carries a similar one. Thanks, Mike!

http://i269.photobucket.com/albums/jj80/Dale53/Castingfan-3723.jpg

The fan not only maintains mould temperature, cools the sprue in two seconds, but also cools the pile of bullets you are casting if the fan is strategiately located. You can move the bullets as soon as you are finished casting. It has made my life just that little bit more pleasant. I can recommend the fan without reservation.

Dale53

JonB_in_Glencoe
09-26-2012, 08:00 PM
The Lee 2 cav. 501-440 is just aweful about getting too hot.
I think there is a larger volume of Lead (when filled) then aluminum in the blocks.
I use the wet towel, but as gear stated, the boolits tend to be inconsistant,
biggest thing is shiney on the top and frosty on the bottom.
my solution is a ballisti-cast 3 cav. Iron mold. I can't wait til it gets here !
Jon

1Shirt
09-26-2012, 08:18 PM
I have no problem dunking Lee single or double cav molds with large blts (over 200 grains). Been doing it for years. Would not do it with other than Alum. molds.
1Shirt!