newbie- sprue sticking to plate

[cephas53]

Howdy, have just started casting, and am pleased with initial results. Kudos to all who post their experience and opinions as it helped me getting started. My equipment is minimal, coleman stove, lead pot, dipper and Lee mould. Surprisingly the only issue I have at this point is that occasionally the sprue doesn't want to fall from the plate after dropping the cast. Using a small metal rod I can easily push it off from underneath through the plate hole. This seems to happen at the point I forget about it happening in the first place. Is this normal or is there something I need to look at. Thanks and have a good one!

[clintsfolly]

try polishing the sprueplate hole (the tapered part of the hole ) this will help clint

[mooman76]

It should come loose if you give the mould a rap with a wood stick, like a piece of broom handle. Don't rap on the mould itself but on the handles, the bolt that hinges it together. Also you could spray WD-40 on the plate. I use Bull plate lube now. If you spray it on while the mould is hot it dries instantly.

[badgeredd]

Also check to see if the sprue plate is too loose and is allowing a bit of lead to stick to the bottom side. I took the plate off of one of my Lee molds and polished the bottom side with 400 grit paper and a little oil on a flat plate. That cured my problem.

Edd

[montana_charlie]

Spray-on graphite (in an aerosol can) makes a good coating for the entire exterior of the mould...and even the handle jaws. Lead just rubs off if it doesn't fall off.

If you still need to use some kind of metal 'pick', use copper wire. It is stiff enough (if not too hairlike) and won't scratch anything.

CM

[copdills]

3 words Bull Plate Lube (look at the bottom of cast boolit page)

[Bullshop]

At times depending on a few things like pour pressure, temp, alloy compasition, and the weight of or tension of the sprue plate to the mold blocks the plate may lift slightly during the pour and when the sprue is cut form a rivet on the underside of the sprue plate that will form a mechanicle atatchment of the sprue to the plate.
Wow hope I said that right.
Anyway when if htis happens it wont be solved by applying any type of release adjent.
If this is the problem it will require a mechanicle fix.
The same situation can also be caused by a sprue plate that is improperly adjusted. There is a proper adjustment to be made with the plate. Start by loosening the pivot screw lock, then completely loosen the pivot screw so that it is not at all touching the plate.
Now hold the blocks up to a bright light and pear across the top of the blocks, under the plate as you are gently tightening the pivot screw.
At some point now you will notice the where the plate has been lying flat on the blocks (unless warped) the end farthest from the pivot screw will pick up from the blocks and show light between. Adjust in and out until you find the point at which the plate lies flat on the blocks with no light showing across the entire block surface. That is the correct tension adjustment for that mold, with that plate.
If any light can be seen that is another condition that can cause the rivited sprue cut and become a real bugger to get the sprue to let go from the plate.
OHMAGOSH! I am late!!! Got to get off to church.
Blessings to all!!!
BIC/BS