WidenersLee PrecisionADvertise hereMidSouth Shooters Supply
Inline FabricationRepackboxRotoMetals2Titan Reloading

Page 1 of 3 123 LastLast
Results 1 to 20 of 41

Thread: Preheating mold

  1. #1
    Boolit Buddy bazzer485's Avatar
    Join Date
    Apr 2016
    Posts
    107

    Preheating mold

    Iím interested in finding out the best method for preheating both aluminum and brass molds. NOE recommend using a hotplate but I find this very slow and nearly impossible to get my molds to the required 400 degrees F. So how do you do it?
    Thanks
    Barry

  2. #2
    Boolit Master
    Join Date
    Oct 2013
    Posts
    810
    aluminum conducts heat so fast you can just stick the end in the pot for a moment.

  3. #3
    Boolit Buddy
    Join Date
    Feb 2019
    Location
    Washington
    Posts
    196
    I use a cheap electric Panini sandwich press. It has a heating plate/element both top and bottom. I paid like $7.00 for it at the thrift store.

    I start heating my molds at the same time as I turn on my Lee 20# pot. By the time the lead is melted the molds are preheated and ready to go.

    JM

  4. #4
    Boolit Master poppy42's Avatar
    Join Date
    Apr 2017
    Location
    Virginia
    Posts
    648
    Walmart cheep hot plate with an old circular saw blade on the coils. I don’t know what kind you are using but it must not be working right. I put 3 or 4 molds on mine, set it on 3 or 4 ( about the middle temperature) and my molds heat up long before my Lee 4/20 melts a full pot of lead!
    Long, Wide, Deep, and Without Hesitation!

  5. #5
    Boolit Bub
    Join Date
    Oct 2019
    Posts
    52
    Edge of slightly open mold in pot. When the lead stops sticking to the mold Iím ready to start.

  6. #6
    Boolit Master
    toallmy's Avatar
    Join Date
    May 2015
    Location
    easternshore of va.
    Posts
    2,341
    Like poppy42 - I preheat on a electric burner with a piece of steel plate on it , turned on about 15 minutes before my lee pot is ready .

  7. #7
    Boolit Buddy
    Join Date
    Aug 2008
    Location
    ar
    Posts
    116
    sit mine atop Lee pot when I turn it on.

  8. #8
    Boolit Grand Master

    Join Date
    Oct 2009
    Location
    England,Ar
    Posts
    6,184
    Quote Originally Posted by poppy42 View Post
    Walmart cheep hot plate with an old circular saw blade on the coils. I don’t know what kind you are using but it must not be working right. I put 3 or 4 molds on mine, set it on 3 or 4 ( about the middle temperature) and my molds heat up long before my Lee 4/20 melts a full pot of lead!
    I do the same thing. Back when I was using an older Lyman pot with the cast iron liner I would set the mold on the edge of the pot. But my Promelt has a thinner stainless liner that doesn't heat as well.

  9. #9
    Boolit Master


    georgerkahn's Avatar
    Join Date
    Sep 2013
    Location
    South of the (Canada) border
    Posts
    1,731
    How I do it? I have a G E Electric hot plate with its thermostat contacts shorted across, plugged in to a PID unit. A small galvanized pot with a grommet-ed hole in rear for the PDF temp sensor; a probe-type oven thermometer epoxied in a hole at top; and, a "door" cut in front for insertion/removal in this "mould-heating-garage" sits atop it. I have the PID set at 375*F, and -- using a RCBS Pro-melt -- the mould in this heats to ~350* -- hot enough except for one or two moulds with pins, which like to be warmer -- at almost the same, exact time my alloy is fluxed and ready to begin my casting session. I rarely use aluminum moulds ('cept for fishing jigs, sinkers, & similar moulds) -- my bullet makers are mostly brass and steel.
    geo

  10. #10
    Boolit Master trixter's Avatar
    Join Date
    Mar 2011
    Location
    Where E. Pine crosses I-5
    Posts
    839
    I use a GE hot plate that has a solid plate cooking surface adjusted to the farthest extent of the MED setting towards maximum heat setting. I turn it on and set the mold on it as soon as I fire up the pot. The pot takes about 28 minutes to come up temp, so I know that the mold is hot enough.

  11. #11
    Boolit Buddy

    Join Date
    Nov 2011
    Location
    East Arkansas
    Posts
    484
    I use the solid top hot plate and set it to right at a little less than medium when I get the melt started and they are ready at the same time.

    I have an 8 cavity H&G and have gotten it too hot twice. That beast takes a while to cool down. When I say too hot it took the sprue about a minute to solidify and the bullets were
    very frosty looking almost pitted looking. It took several minutes of sitting on a wood block to get the temp right.

  12. #12
    Boolit Grand Master
    bangerjim's Avatar
    Join Date
    Apr 2013
    Location
    out of here, wandering somewhere in the SW.
    Posts
    8,877
    After trying a bunch of methods, I use an industrial variable heat hotplate. I goes from warm to lead-melting temps and beyond. It is flat so molds lay nice and flat. If you are lucky you can find one like it (1200-1500W element) in a junk store. They can sell for over $300 new and are lab quality.

    But a hotplate (the RIGHT ONE) is the only way to go!
    banger

  13. #13
    Boolit Master Ed_Shot's Avatar
    Join Date
    Sep 2010
    Location
    North Texas
    Posts
    910
    Quote Originally Posted by poppy42 View Post
    Walmart cheep hot plate with an old circular saw blade on the coils. I don’t know what kind you are using but it must not be working right. I put 3 or 4 molds on mine, set it on 3 or 4 ( about the middle temperature) and my molds heat up long before my Lee 4/20 melts a full pot of lead!
    Also, exactly what I do.

  14. #14
    AKA: GRMPS Conditor22's Avatar
    Join Date
    Dec 2018
    Posts
    1,795
    Sounds like you have a bad hotplate.

    I have a piece of 1/4 steel on top of mine and like previously mentioned a little less than Medium is 400į

    https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

    It was a lot cheaper when I bought mine. since then I've seen many for 3 - 5 $ in thrift stores.

  15. #15
    Boolit Man

    rockydoc's Avatar
    Join Date
    Aug 2013
    Location
    Northwest Florida
    Posts
    91
    You can get one of those inexpensive laser thermometers from Harbor Freight to check the temp of the moulds and then adjust the hot plate temp accordingly. The hot plates with the solid tops are better than the ones with the coil top. Cheap from Walmart, cheaper from thrift shop.
    NRA Lifetime member since 1956, NRA Endowment Member. Reloading since 1954. CBA Member Navy Vietnam Veteran USS Intrepid CVA 11

  16. #16
    Boolit Master
    Join Date
    Jul 2013
    Location
    barry s wales uk
    Posts
    2,022
    i just fill the molds im using and let them sit for a couple of mins .seems to work with ally and iron molds

  17. #17
    Boolit Buddy

    Join Date
    Jul 2010
    Location
    N. Canton, Ohio
    Posts
    316
    IMHO, dipping the mold into the lead pot takes forever. like so many have suggested; some kind of cooking heat source. a propane or mapp gas torch would be my second choice. to measure the temp. you can buy these sticks called; "temp sticks" they melt at a given temp.

  18. #18
    Boolit Buddy
    Join Date
    Jun 2014
    Location
    Northern California
    Posts
    261
    I use a cheap Walmart hotplate set just below Medium and put an an aluminum lasagna pan over the mold to speed up the mold heating.
    I also use a Lee pot with a PID set at 710 Deg. F.

  19. #19
    Boolit Master daloper's Avatar
    Join Date
    Jul 2016
    Location
    Sparta Michigan
    Posts
    534
    I have a piece of copper flat that I mounted an square electrical box with the end cut out of it sit on my hot plate and it acts as an oven. I have it under the exhaust fan so I don't have to worry about the galvanized box giving off any fumes.

  20. #20
    Boolit Buddy
    Join Date
    Apr 2012
    Location
    Utah
    Posts
    345
    Quote Originally Posted by poppy42 View Post
    Walmart cheep hot plate with an old circular saw blade on the coils. I don’t know what kind you are using but it must not be working right. I put 3 or 4 molds on mine, set it on 3 or 4 ( about the middle temperature) and my molds heat up long before my Lee 4/20 melts a full pot of lead!
    I do the same, heats up the mold in no time.

    OP I would say your hot plate is having problems as any old cheap hot plate shouldn't have any trouble heating a mold. I think I paid $5 for mine a few years ago.

Page 1 of 3 123 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check