PDA

View Full Version : Loose sprue cutter screw



Divedigger
12-01-2018, 03:56 PM
Whats the trick to keep sprew cutter screws in place? Staking? Thanks

tazman
12-01-2018, 04:00 PM
Depends a lot on who made the mold. Most iron molds have set screws already installed that just need tightened. Lee aluminum molds will need to have a set screw installed or you will need to keep a pair of pliers handy.

Grmps
12-01-2018, 04:29 PM
Divedigger- welcome to CB. If you decided to start casting to save money, forget it. You won't, you'll just shoot more.

There are several methods of securing sprue plate screws. I would assume you are talking about an aluminum Lee mold.

staking is an option and some people stick the thin wire down the hole or wrap the threads with it.

the best ( my opinion and like taz said) is to drill and tap a brass set screw (I use 10-32) to secure the sprue plate screw.

Lubing the friction point between the screw and the sprue plate (with synthetic 2-stroke oil) will help keep the screw from working loose (be carefull not to use to much or it will get into a cavity and give you wrinkled boolit. I use a bottle like these https://www.amazon.com/Needle-Dispenser-Solvent-Applicator-Dropper/dp/B00UG08QDC/ref=sr_1_3?ie=UTF8&qid=1543696099&sr=8-3&keywords=needle+dropper+bottle

Casting boolits (lead bullets) properly is a science, once you know the basics, not a hard science.
There is a lot of good information on CB. The Google search (top right of every forum page) is a gateway to all the knowledge on this forum. IF you can’t find your answer there ask the question (Please be as detailed as possible, pictures help http://castboolits.gunloads.com/showthread.php?344661-Capturing-amp-Posting-screen-shots I would be very surprised if there wasn’t someone on this forum that could answer ANY (firearm related) question you might have)
http://www.lasc.us/Fryxell_Book_Contents.htm
1. Boolits need to be cast .0005 to .003 (normally .002) over the slugged diameter of your barrel for accuracy and to avoid leading. If the fit is wrong nothing else will work right.
a. slugging a barrel (it is safer to use a brass rod or a steel rod with a couple of coats of tape to avoid damaging your barrel http://7.62x54r.net/MosinID/MosinSlug.htm
b. chamber casting https://www.brownells.com/guntech/cerrosafe/detail.htm?lid=10614
or pound casting http://castboolits.gunloads.com/showthread.php?356251-Pound-Cast-instructions-(for-rifle-chamber)
2. the right alloy needs to be used for the velocity and purpose of the boolit (don’t fall into the trap of going with too hard an alloy
https://i.imgur.com/FD4XW69.png
Economical way to easily test lead hardness
http://castboolits.gunloads.com/showthread.php?355056-Easier-pencil-lead-hardness-testing
https://i.imgur.com/TrOTWFb.png
Some alloys harden over time
http://www.lasc.us/Fryxell_Book_Chapter_3_alloySelectionMetallurgy.ht m
different alloy’s different end hardnesses
https://i.imgur.com/O8uvZ8i.png
https://i.imgur.com/MHPjxfp.png
Lead alloy calculator
http://castboolits.gunloads.com/attachment.php?attachmentid=45784&d=1341560870
3. velocity the bullet needs to be pushed hard/fast enough to get the proper spin, have the proper velocity to accurately reach the target but not so hard as to be dangerous or strip the lead off in the grooves instead of spinning the boolit..
The boolit needs to be the right weight for the riffling/twist rate of your barrel
Powders range from fast to slow, you need to choose the right powder for your barrel length & application.
Loading manuals list the best powders for certain calibers and boolit weights.
NEVER use any posted noncommercial load data without first checking commercial load data to see if falls in the safe parameter for your firearm!! There are several firearms out there that can handle much higher pressures than others!!
Link to free online load data
http://castboolits.gunloads.com/showthread.php?337910-CB-load-data-online-sources

jcren
12-01-2018, 04:38 PM
Lee molds, either drill and tap the side of the mold for a set screw, or wrap a couple strands of steel wool around the screw and reinstall.

El Bibliotecario
12-01-2018, 09:11 PM
Whats the trick to keep sprew cutter screws in place? Staking? Thanks

I keep a scruedriver handy when I am casting to periodically tighten the sprew cutter screw.

tazman
12-01-2018, 11:36 PM
One lasr detail to help keep the screws tight. Use oil(preferably 2 cycle motor oil) as a lubricant on the pivot points. This will make opening and closing the mold easier and put less stress on the screws. Also use it on the locator pins for the same reason.
Use only a very small drop. The oil will try to migrate into the cavities and cause wrinkles.

MT Chambers
12-02-2018, 12:00 AM
The Lee screws come loose and them when you try to tighten them they break, you will prolly need to re-tap them for a dif. thread and use another screw from the side to keep the new screw tight, the alum. is very soft.

centershot
12-02-2018, 01:52 AM
One lasr detail to help keep the screws tight. Use oil(preferably 2 cycle motor oil) as a lubricant on the pivot points. This will make opening and closing the mold easier and put less stress on the screws. Also use it on the locator pins for the same reason.
Use only a very small drop. The oil will try to migrate into the cavities and cause wrinkles.

Divedigger,

Use a Q-tip to apply the oil.

Get the mold up to temp first and make several pours.

Cut the sprue on the last one but LEAVE THE BOOLITS IN THE MOLD!

Put ONE drop of oil on the Q-tip, with the sprue plate closed, apply oil to the seam between the plate and the block, especially at the corner where the pivot is located.

Open & close the plate several times.

Open the plate and apply a thin bead of lube on the BOTTOM of it on the side OPPOSITE the pivot.

Open and close several times and dump the boolits.

Now, go cast boolits!

When you feel the plate start to drag a little bit, re-lube.

centershot
12-02-2018, 01:57 AM
And, Lee molds are notorious for this particular problem. Pick up a drill & tap set and a tap wrench, along with a few set screws from the hardware store. You'll be prepared for "the next time"!

Wally
12-02-2018, 09:47 AM
Take a small strip of aluminum and place in the Sprue screw hole and then screw in the screw--it will hold it tight. Or you can use fine copper wire, which also works well. When you feel the sprue plate is tightening up, when casting, touch a small candle to the top of the sprue plate screw head. If the sprue plate is galling (lead is sticking to it), wipe off with and oily rag immediately after opening it.

sundog
12-02-2018, 09:54 AM
I have one 6-cav Lee mould that I just drill straight thru and installed a bolt and locking nut. Its ugly and does not sit flat, but it works. The rest of my many Lee moulds a side D&T'd for a set screw - usually done before the first cast.

Divedigger
12-03-2018, 08:14 PM
Whats the trick to keep sprew cutter screws in place? Staking? Thanks

Thanks for all the tips. They are lyman 4 cav molds so I got a good bottle of 2cy oil and q tips ready for the next round of casting!

OldBearHair
12-03-2018, 08:29 PM
Thank you Grmps for providing all that good information in post #3 to the new people. And they are not the only ones who benefit.
To the OP Divedigger, On one of my molds I put some JB Weld on the threads and it holds good for a time but not forever if it gets too hot! You have to be double sure it is adjusted just right before the glue sets up. All this in case you don't have the other options available to you.

midnight
12-04-2018, 07:31 AM
I use what is called a wave washer or spring washer. I keep both 5mm & 6mm sizes. It works especially well on old collectable molds you want to use but not modify.

Bob

Divedigger
12-06-2018, 05:25 PM
My aluminum molds have handles on sprue cutters but I got a box ful of older Lyman steel molds some still in the metal reinforced corner boxes and all the cutters are to be tapped open with a mallet so I think thats where it keeps getting loose. Has anyone attached a wood handle on the cutters to make things go smoother? A steel 4 cav 358xxx starts getting heavy after a few minitues and begins working on the wrist plus have to pick up mallet and tap sprue open. I just need to work on my skills more with these heavy molds as it is night and day different from the aluminum being the hinge point is different and the sprue handle seems to help in handleing the mold. I am open to any comments and suggestions. Thanks

Grmps
12-06-2018, 05:56 PM
The box full of older Lyman steel molds should already have set screws.

Check this for your Lee molds --- http://www.castpics.net/subsite2/MoldMods/LeementingKitDocumentation.pdf

toallmy
12-06-2018, 06:02 PM
Are the sprue plates tightened down a little to much , or do they just need to be lubed to get them freely opening and closing ?

john.k
12-08-2018, 08:35 PM
i find if you lube the mould pivots with bees wax,after a while the stuff carbonizes and sticks the sprue screw tight......no more issues............its possible a spot of loctite would do too....loctite does soften with heat,but it stays sticky,so it would be OK......I havent tried it yet.