Home Made Constant Pressure Mold Handles

[rbertalotto]

I was made aware of boolits dropping heavier towards the end of a casting session as your hand and therefore grip gets tired. Makes sense to me!

So I decided to do something about it and modified a set of locking pliers to accept boolit molds and hold the molds closed exactly the same from the beginning of the session to the end.

http://images53.fotki.com/v536/photos/2/36012/9874505/0704111647-vi.jpg

http://images33.fotki.com/v1074/photos/2/36012/9874505/0704111648-vi.jpg

I wrote a whole "How To" article on my web site so you can build one also.......

www.rvbprecision.com

Now I need to try it out to see if it improves my boolit weight consistency.

Thanks!

[montana_charlie]

Now I need to try it out to see if it improves my boolit weight consistency.
A test to learn the same thing using a different set of handles.
http://www.shilohrifle.com/forums/viewtopic.php?f=5&t=17399

CM

[no34570]

Awesome mate,good idea,have to TRY and make them too(not real good in the tech side of things) :)
A+

[bpratl]

Great idea....thanks, I will be fabricating a set very soon. A couple of days ago my hand got numb after casting 400 200 grain bullets from a four cavity iron mold and I quit when I was starting to get flashing from not squeezing the handles enough.

[rbertalotto]

Glad you like them. Be sure to post pictures when you build yours.

[badbob454]

dont the handles get hot? not to mention the springs.

[rbertalotto]

So far so good. With the proper cadance the handles got warm, but not too hot to handle with gloves. I hadn't thought about the spring, but it seems to be working fine. Used them for an hour tonight with no issues.

[Calamity Jake]

The only the that spring does is pull the jaws open when you release the grip and keep the adjuster in place, they'll work just fine with out it.

[tackstrp]

been thinking about something simalar but using two or three lee two cavity molds. But would need to have something that can be automated to open and close the modified vice grips. Problem that creates may not be able to pick up the comtraption.

Like you idea . keeps the weight down to something reasonable.

[JTknives]

plus you have to get the spring hotter then 450deg to start affecting the temper and maybe hotter then that depending on what thy tempered it at originally. most springs are tempered around 500-600 deg depending on the steel

[bpratl]

Inspired by rbertalotto, I decided to fabricate a set of handles like his. Even though they a bit heaver I get less fatigued because I am not squeezing them until my hand gets numb. I am also not getting any more fining when my hand gets tired.

http://i160.photobucket.com/albums/t191/BobPratl/JUL001.jpg
http://i160.photobucket.com/albums/t191/BobPratl/JUL002.jpg

[rbertalotto]

So Cool! (and I bet those handles are cool, also)

Nice work........Have you used them yet?

[bpratl]

So Cool! (and I bet those handles are cool, also)

Nice work........Have you used them yet?

Just a trial run yesterday as I was waiting for the handles to dry. I will give them a workout this
weekend.

[rbertalotto]

UPDATE:

Results with "Constant Pressure Pliers Handles"

I finally had a few moments to analyze the results of using the constant pressure handles I built;

http://images55.fotki.com/v608/photos/2/36012/9869255/P1020784-vi.jpg


As you can see. Huge improvement. 3.7g variation. I'm still not sure how you folks are getting 1/2 grain variations. I have a long way to go to get there. But this is huge for my stage in the game.

Here's a quick video of how the pliers are connected to the temperature probe.

BTW, I found my best bullets were cast with the "1-20" Allot at 750 degrees and the Lyman mold at 425 degrees..........

http://public.fotki.com/Rbertalotto/gunsmithing-reloading/constant-pressure-m/p1020782.html

A few notes on the pliers......

At 425 degree mold temperature, handles got to 91 degrees. No issue even with thin welding gloves.

The tension set screw on the pliers will need a set screw installed or a jam nut to stop it from loosening during use. When the handles are opened to drop a boolit and the pliers are tapped with a wood mallet, the screw is no longer under tension and will loosen after a few taps.

I had to modify the jaws on my pliers. I ground them so only the area around the bolt that holds the pliers to the mold was touching. Before I made this modification the tips of the jaws were holding the top of the mold tightly, but the bottom of the mold showed daylight. I'll do a quick sketch and post.

The handles act as a very good heat-sink on the mold. It was hard to keep the Lyman single cavity mold at 425 degrees. If I slowed down my cadence the mold would go to 400 degrees within 20 seconds. (I did have a fan running to keep me cool and I'm sure it was drawing heat away from the pliers)

It's extremely convenient to be able to "lock" the pliers and then go about pouring and sprew removal without worrying about applying constant pressure.

All in all, very pleased with the results.

[rbertalotto]

http://images9.fotki.com/v250/photos/2/36012/9874505/07102011054649PM1-vi.jpg?1310334577

[Doc Highwall]

The only thing I would like to mention is, I would put the temperature probe on the other side of the mould away from the sprue plate so it will not interfere when cutting the sprue.

[rbertalotto]

The only thing I would like to mention is, I would put the temperature probe on the other side of the mould away from the sprue plate so it will not interfere when cutting the sprue.

CORRECT! It IS in the way. I'm going to redrill to relocate it to the rear, toward the handles, then it will be totally out of the way.

Good eyes!

[bpratl]

I finally had a chance to properly test my Vise Grip Mold Handles and I am very pleased with the consistent drops and less hand fatigued. I was able to cast double the amount that I normally do for a casting session.

[badbob454]

I only hold the handles long enough to fill and watch the extra lead on top flash over to solid then i rest it on a metal file pan whilst i fill a second one , set it down after flash over , i dont get tired because im not always holding a mold ,, then i knock off the sprue with a closet rod wooden dowl @20 '' long , water drop and fill then knock the other sprew cutter and fill so i dont have to always hold one mold ... this may help to alleviate hand fatigue but if this is better for you ... then kudos a good idea, score for you .. whetever it takes to enjoy !!