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nwilson1024
02-24-2012, 02:13 AM
So im still fairly new to casting and have cast about 2000 45 acp. Most of them being with one of MiHec’s hollow point molds and a few hundred with a lyman SWC. My concern is with my MP mold. Here is what I think happened…

I cracked the sprue plate open (using a wooden hammer handle), opened the mold, pushed the pins out, and turned the mold over. Only casting a few times with the mold I don’t think it’s entirely broken in yet, and the boolts were not falling off the pins easily. So I would use the wooden handle to strike the nut on the mold handles. What I think happened is that I struck the sprue plate with the mold turned over, pulling the sprue plate away from the top of the mold ever so slightly. The symptoms are when I close the sprue plate over the mold I can a little bit of light at the end of the mold (furthest from the sprue pivot end). The boolits from the furthest two cavities are coming out with bases that have little….tales on them from the area between the mould and the sprue plate. This is a new problem which leads me to believe that it is my fault…
any way to straighten the sprue plate back out without doing any more damage to it or the mould?

Take it off and put it in a vice between two straight pieces of metal? Im thinking it might just spring back to the position it is in now…

Putting it in a vice and try to bend it back? Im worried about bending it too much or in the wrong place…

Having it machined flat? The sprue holes will be bigger….

Do I have to buy another one?

Thanks guys!

stubshaft
02-24-2012, 03:17 AM
Find a piece of plate glass or steel that it perfectly FLAT, place your sprue plate on it and see if there is a bend in it. You can put it in a vise with safe jaws (lined with leather or lead, copper sheet and try to bend it back, if it is bent. You can also use wet or dry sandpaper on that same plate of glass to sand the plate back smooth. If the sprue holes enlarge slightly no big deal!

This is all assuming that you checked the pivot screw for proper tension.

41 mag fan
02-24-2012, 10:47 AM
Mihecs sprue plates are pretty thick pieces of metel, to bend it would take quite a bit of force.

I learned the glove works better, I bent a sprue plate of a Lee. But Mihas sprue plates are thicker and better quality of metal too.
Could also be the sprue plate was too hot and warped?

MT Gianni
02-24-2012, 11:30 AM
Mihec should be able to get you another sprue plate if you cannot fix it.

lbaize3
02-24-2012, 12:29 PM
Smoke the ends of the pins with a Bic lighter. That will help the boolits fall off better. I use a thick towel folded over twice as a cushion for the boolits, but I turn the mold upside down and place it on the towel before I tap the handle nut. That keeps the sprue plate from being bounced and bent.

nwilson1024
02-24-2012, 02:54 PM
thanks guys, ill try the glass idea to see where the bend is.

lbaize3, i did smoke the pins but it only seams to work for a few (2 or 3) then they start to stick again, and i have to re-smoke them. the pins seams to have slight machine marks that i might be able to get smoother with some fine sandpaper or something.

stubshaft
02-24-2012, 03:04 PM
The pins are getting too cold! You have to get your cadence up to insure the pins will maintain their heat. CAST FASTER.

nwilson1024
02-24-2012, 06:02 PM
I think the pins are getting up to the proper temp because one of the pins has no problem letting the boolits fall free, but some are more troublesome than others. even when i move the pins around to different locations the same 3 still stick... 2 badly and the 3rd usually comes free on the first rap on the handle nut with the wooden handle.

stocker
02-24-2012, 07:57 PM
Do the same cleaning and prep work on the pins that you do on the mould. Soap and water, alcohol etc. Smoke lightly and keep them hot. What is the mould made of? I've found I have to keep the melt a bit hotter for aluminum blocks otherwise the blocks suck the heat out of the pins and result in poorly formed cavity edges and stickiness.

tcbnick
02-24-2012, 08:53 PM
I did what I call a trigger job on my penta pins. Took a small fine file to the sides of the pins and right at the base where it changes from pinta to round, I think that is the most important part. MiHec moulds are a pleasure to use though.
Thanks Nick

cbrick
02-24-2012, 09:34 PM
As to the bullets sticking on the pins re-read post #7, stubshaft nailed it.

It sounds like your pins are nearly hot enough but not quite there. The pins do not have the mass to hold heat like the blocks do and they cool off far faster than the blocks. Dump the bullets and close the mold as fast as possible and re-fill as fast as possible. While you admiring your new HP's with the pins sticking out in the air those pins are cooling fast. A HP pin too cool will hold a bullet like it's welded on, heat that same pin up and they fall off.

Rick

blackthorn
02-25-2012, 02:57 PM
To flatten a warped sprue plate or other (supposed to be flat) piece of metal, place it on a smooth faced anvil or other piece of smooth, flat, steel. Your vise may have a large enough surface; just make sure the entire piece can lay flat on it. Use a smooth leather-faced wooden mallet, and you can make the metal perfectly flat.

runfiverun
02-25-2012, 03:05 PM
look for a bit of lead under the sprue plate right by the screw.
or just loosen it a tad.
i doubt you bent it,it's probably just a bit tight.
i have some molds that the tension changes when they go from cold to hot.

Bill*
02-25-2012, 10:36 PM
Is it possible you bent the screw rather than the plate?

nwilson1024
03-04-2012, 05:35 PM
I took it apart today and dosen't seam to be any damage to the screw itself. Put it back together and still see light between the mold and spru plate. Going to try wacking on it on a flat steel plate.