Cutting the spruce

[Gundogblue]

This may be a dumb question but how long approx do you guys wait in seconds before you cut the spruce. The reason I ask is because on my first batch of cast boolits I was cutting the spruce way too soon, and got lead smears all over the top of the mould, and some really ugly boolits. I had to use a propane torch to clean the lead off the top of the mould, so now after the lead has been poured into the mould I count to 15 before I cut the spruce, but that may be waiting too long. As usual any advice is always greatly appreciated.
Thanks
Paul

[Tonto]

as you cast, you will see the sprue color change as it solidifies...waiting a couple of seconds more before you cut is usually right and as you've learned, too soon and you get smears.....treat the mould top with a 2-cycle oil and a q-tip as described elsewhere in these forums, that helps a lot with the smear prevention....
or as your title says, cut the spruce, either a handsaw or chainsaw make quick work

[jeepyj]

I watch the puddle of lead harden then about one second after that I give her a whack. The key is watching the lead transform from a liquid to a solid. That when it kinda sucks down inside the mold to finish fill out. This method is a bit harder if your pressure casting but unless I have a problem mould I like to see it harden.

[Beagle333]

I cast pretty hot and I wait about 7-8 seconds. So I can't really see needing to go to 15 unless you are casting really hot (as in, making deep HP's using pure lead). Everybody will have a different technique and time. I cut the sprue with my gloved hand, and if I have waited until it is actually difficult to push the plate off the mold and cut the sprue, that tells me that I have waited a couple seconds too long and I have to reach for the stick and know that I should speed up a little.

Also, smear a light coat of sprue plate lube (synthetic 2-stroke oil) on the bottom of the sprue plate with a Q-tip and then wipe all of it off with a piece of denim or burlam, about every 40-50 pours and it will help with reducing any smearing or buildup. (You can't get it all off, that's the point. The invisible layer that is left will be enough to protect the plate and top of mold, but not enough to migrate into the cavity and cause problems) Learn to do this quickly and without letting the sprue plate or mold cool very much at all.

[largom]

Watch the puddle change from liquid to solid, only takes a few seconds, maybe 10. I then cut the SPRUE with a gloved hand by pushing down and out.

[mehavey]

When the lead puddle color goes "flat", you can cut the sprue.
NOTE: by just 'breaking' the sprue plate loose slightly -- then wait just a half second before fully opening -- you can dramatically minimize lead smear

[lightman]

I also watch the color change from silver to dull grey. I give it another second or two and then cut it. The time to do this can vary from molt to mold.

[Strtspdlx]

learn to watch the puddle. don't worry about time in seconds and such, watch the puddle, when it changes state and exterior appearance you should be ready, time is good for managing mold temp. but all things considered, if you cut the sprue and the bottom of the boolits wipe across the mold blocks or look like they haven't solidified, your mold is too hot. if the are solidified and ready to drop, then get after it.

[unique]

Watch as others say but sometimes the spruce can appear to solidify quickly but internally the spruce is still not quite solid so you can end up with smearing.

What I sometimes do is give the spruce a little tap with my wooden handle and note how solid it is. I judge the dent produced to tell me how solid the spruce is. This works very well.

Also, I use pencil to cover areas prone to smearing. Oil works well but I somehow always manage to get some inside the mould which takes time to burn out.

[Larry Gibson]

"Cutting the spuce"

This time of year I don't want one over 7' tall so a small pruning saw works fine. Larger ones I use a chainsaw..........

Merry Christmas...........

[Walter Laich]

after awhile you will have the timing down and not have to worry about it--it will have become muscle memory

[RCE1]

I have been touching the spruce to a dampened sponge for a second, once the lead has gone matte. This is something new for me, but last casting session, I went through a whole load of lead in the RCBS bottom pour and got essentially zero smearing. I was using an RCBS two cavity 429-240 SIL.

[runfiverun]

I use a count.
there is a clock on the wall behind my casting pot.
tick,tick,tick,tick.

I normally average @3-4 pours a minute.
2-3 ticks to fill, 5-7 ticks before opening, 2 ticks to put the sprue in the pot, 2 ticks to dump the bullets.
heat gain and heat loss is maintained through time, any faster and the mold gets too hot, any slower and I lose too much heat.
I pay attention to the ticks and take what the mold gives me.

[dragon813gt]

1,209,600.....we typically cut a blue spruce down two weeks before Christmas

[Victor N TN]

learn to watch the puddle. don't worry about time in seconds and such, watch the puddle, when it changes state and exterior appearance you should be ready, time is good for managing mold temp. but all things considered, if you cut the sprue and the bottom of the boolits wipe across the mold blocks or look like they haven't solidified, your mold is too hot. if the are solidified and ready to drop, then get after it.

What this guy said. Time today may not be the same time next week. 6 to 8 seconds may not work if the pot or mold is too hot.

[Handloader109]

Absolutely watch the puddle and I totally agree if you can't cut sprue with your gloved hand, you waited too long. I only hit plate for first few pours when it is not entirely up to temperature. Watch when it is hard enough it does go flat/darker.

[Ateam]

Interesting thread, I have always tapped my molds open with a chunk of wood, just the way I was taught. Is this wrong? Sorry for the hijack.

[whisler]

Not wrong, it is just easier not to have to juggle a stick to open the sprue plate.

[JSnover]

Interesting thread, I have always tapped my molds open with a chunk of wood, just the way I was taught. Is this wrong? Sorry for the hijack.

I won't say it's wrong because so many people have done it for so long but I gave it up a while ago. The sprue plate needs to fit properly and only has one screw holding it on. Whacking it open seemed rather abusive to me.

[dragon813gt]

Interesting thread, I have always tapped my molds open with a chunk of wood, just the way I was taught. Is this wrong? Sorry for the hijack.

When the mold is up to temp you should be able to open the sprue plate by hand. This speeds up the entire casting process and is easier on the mold. Ergonomically it's better as well but I don't expect most casters to care about that or economy of motion.