Lyman Mag25 Service manual

Mag25
Furnace
Operation an
Assembly Instructions

Operation an Assembly Instructions
Warning: elting lead and casting lead objects will expose you and others
in the area to lead, which is known to cause birth defects, other reproduc-
tive harm and cancer.
Reducing Exposure: Lead contamination in the air, in dust, and on your skin
is invisible.
Keep children and pregnant women away during use and until cleanup is
complete.
Risk can be reduced – but not eliminated- with strong ventilation; washing
hands immediately after use of these products, before eating or smoking;
and careful cleaning of surfaces and floors with disposable wipes, after lead
dust has had a chance to settle. Use a lead specific cleaner with EDTA, or
a high-phosphate detergent (like most detergents sold for electric dish-
washers) and bag wipes for disposal.
- 2 -
Figure 1
Handle
Pivot Stud
Limit Screw Shut-Off
Rod
Handle

Assembly
The main body of the furnace is fully assembled and factory tested. To facil-
itate packaging, the shut-off rod and operating handle have not been in-
stalled and you must do so prior to using the furnace.
To attach the handle: slide the shut-off rod through the hole in the alignment
plate and down into the valve in the bottom of the pot. Next remove the
screw from the handle pivot stud. Then slide the handle with its tension
spring through the slot in the shut-off rod. Slide it in until the end of the
shut-off rod slips into the slot in the handle pivot stud and the hole in the
shut-off rod aligns with the hole in the pivot stud. Tighten the supplied screw
through the handle and into the opposite side of stud. See Figure 1. Thread
the supplied shut-off rod limit screw (with its lock nut) into the threaded hole
in the alignment plate. Your furnace is now ready to be used.
Han ling Lea
Lead, a substance known to cause birth defects, reproductive harm and
other severe physical injury, must be handled with extreme care. Handle lead
bullets or lead shot only in well ventilated areas and ALWAYS wash hands
after handling lead and before eating or smoking. Discharging firearms in
poorly ventilated areas, cleaning firearms, or handling ammunition, also may
result in exposure to lead. Have adequate ventilation at all times.
Safety Precautions
1) No casting should be done without basic safety garb. This would in-
clude long pants and long sleeves, sturdy gloves, eye protection and
closed top shoes.
2) Keep all flammable items away from casting area. Do not operate unit
on flammable materials such as paper, wood or carpeting.
3) Casting should be done in a well-ventilated area. Avoid breathing fumes
and dust from furnace.
4) Never allow moisture near molten lead. When moisture is introduced to
molten lead, a terrific steam explosion occurs and molten metal is
sprayed not only over the immediate area but also over the bullet
caster. This moisture could be introduced by a wet ladle or dipper, over-
head pipes, or additional lead being added to the pot.
5) Keep children away from casting and reloading areas.
- 3 -

6) Never pick up or tip the furnace when it is hot.
7) Do not cast when distracted.
8) Do not smoke or eat while handling lead.
9) Do not run the furnace without lead. (Except for initial warm-up period.)
10) Only plug the furnace into a circuit that can handle an additional 7 amp
draw.
11) Wash hands after handling lead.
12) Use caution when adding bullet metal to the furnace containing molten
metal to avoid splashing.
How to Use the Warming Shelf
The warming shelf is located on the rear rim of the pot and allows you to
pre-heat your mould blocks while the furnace is bringing your bullet metal
up to casting temperature. Single and double cavity moulds are best stood
on end with the handles straight up. Four cavity blocks are best positioned
horizontally on the warming shelf. The use of the warning shelf will help re-
duce the time needed for a mould to being producing good wrinkle free bul-
lets.
Moul Gui e – Alignment an Use
The ag 25 mould guide is designed to accept moulds made by Lyman,
RCBS, Saeco and Lee. There are two steps on the mould guide rails which
will fit these various moulds. Note: It is recommended that the mould guide
be adjusted when the furnace is cool and not in use.
To adjust the mould guide, loosen the two wing nuts on the right hand side
of the furnace. Place your mould on the guide rails and position it below the
drain spout. Slide the mould guide up or down as needed to leave about ¼”
space between the spout and the top of the mould. Tighten the wing nuts to
lock it in place. Next, the side to side position of the guide can be adjusted if
needed. See Fig. 2.
Loosen the bolt at the back of the mould guide with the supplied wrench
and move the mould guide side to side so that the drain spout aligns with
the mould sprue plate hole.
- 4 -

To stop the mould in the correct position under the drain spout, the mould
guide is also equipped with an adjustable mould stop. Loosen the thumb
screw on the side of the mould stop, and position it so that it will stop the
mould when the last sprue hole in the mould is centered under the drain
spout. When it is in the correct position, lock it in place with the thumb
screw.
When using the mould guide with a multiple cavity mould, the mould is set
onto the guide rails and slid forward until it touches the mould stop. The
cavity closest to the operator is filled first. The remaining cavities require vi-
sual alignment with the drain spout and are filled (each in order) as the
mould is slowly drawn towards the operator. When all cavities are filled,
allow the mould to rest on the guide for several seconds until the sprue so-
lidifies.
Operating Your Furnace
Plug in your furnace to turn it on. (Unplugging it will turn it off.) Up to 25
pounds of cold bullet metal can be added to the pot. Note: before using
your new furnace for the first time, we suggest you turn it on when empty
and set the furnace for the desired temperature. Then allow it to run for 10
to 15 minutes in a well-ventilated area (better yet, outdoors) to burn off pro-
tective oil. The unit usually smokes a bit at first which could be a problem
inside your house.
The ag 25 furnace is equipped with a multi-function digital temperature
controller. The controller has two temperature displays. The lower display
marked “SV” (set value) is the temperature that the furnace is programmed
to run at.
- 5 -
Figure 2
Bolt used to adjust side to
side position
ould Stop

The upper display marked “PV” (process value) is the actual temperature of
the metal (+ or – approximately 10 degrees F. Please note that this temper-
ature tolerance is for a typical volume of lead. If filled right to the top or
drained close to empty, the temperature tolerance can be a little greater.)
The furnace is factory set for a maximum temperature of 850 degrees F.
While the controller is capable of multiple functions, the caster will only
need to be concerned with basic temperature changes and other functions
are locked. To change the temperature setting, tap the Up or Down button.
(See Figure 3 for identification of keys.) The set temperature in the “SV” dis-
play will flash. ove the temperature up or down with the appropriate but-
ton. The temperature will change in 10 degree increments. Once the
desired temperature is selected, wait a few seconds and the display will
stop flashing, showing that the temperature has been changed.
From this point on the furnace will automatically cycle on and off to main-
tain the set temperature. When heating or attempting to keep the tempera-
ture within its tolerance range, the “OUT” (output) light will be on. It will blink
as the actaul temperature reaches the set temperature. If the light is off, the
furnace is not heating. If the actual temperature raises approximately 20°
above the the set temperature, the heater will cycle off automatically, drop-
ping the temperature back down to the set level. When the controller is not
attempting to adjust the temperature, no indicator lights will be on.
If the unit temperature reaches r exceeds 950°, the PV reading will
sh w “Err” and the AL light will c me n. If this happens, unplug the
unit and c ntact Lyman Cust mer Service.
You may see some movement up or down in the actual temperature read-
ing as the heat is cycled on and off. You may need to experiment with differ-
ent temperature settings to find what works best with a particular mould.
- 6 -
Process Value:
Actual temperature
of lead
Set Value:
Temperature
that the furnace
is set for.
These buttons
are not used
Down Reduces
Temperature
Up Increases
Temperature
Figure 3

When adding additional lead to the pot, you will see the temperature drop
on the “PV” display, as the new cold lead will lower the temperature of the
existing lead. The furnace will automatically heat until the molten lead is
back up to the set temperature.
Bottom Pour System
The bottom pour spout valve system of the furnace has been designed to
provide efficient trouble-free casting. The system consists of the drain
spout, shutoff rod and limit screw. The shutoff rod limit screw is used to con-
trol how high the shutoff rod can be lifted, which in turn, controls the flow
rate of the lead. Determine the best flow rate of lead from the spout for the
particular mould you are using and adjust the limit screw to stop the shutoff
rod at this point. CAUTION! Limit screw will be h t during adjustment!
Dripping from the valve can occur at times if dirt or grit suspended in the
molten lead gets caught in the shut-off valve. Fully opening the valve will
usually clear such debris. When this does not work, drain the furnace and
allow it to cool. Then remove and clean the shutoff rod. If the drain spout is
seriously clogged, heat the furnace to the melting temperature. Hold an un-
bent paperclip with pliers and feed the wire up through the drain spout to
dislodge any obstruction. Be careful to wear heat resistant gloves and eye
protection whenever working with molten lead.
Parts List
1) Power Cord, 115 Volt .................................................. Item # 2800400
2) Power Cord, 230 Volt (Euro) ....................................... Item # 2800401
3) Power Cord, 230 Volt (Australian) .............................. Item # 2800402
4) Shut-off Rod ............................................................... Item # 2800403
5) Shut-off Rod Limit Screw............................................ Item # 2800404
6) Limit Screw Lock Nut.................................................. Item # 2800405
7) Handle Assembly........................................................ Item # 2800406
8) Housing Screws.......................................................... Item # 2800407
9) ould Guide Assembly............................................... Item # 2800408
10) ould Guide Wing Nuts.............................................. Item # 2800409
11) ould Guide Support Screw ...................................... Item # 2800410
12) ould Stop Assembly................................................. Item # 2800411
13) ould Stop Thumb Screw .......................................... Item # 2800412
- 7 -

- 8 -
Lyman®
Visit our website to
see our full line of pro ucts,
or request a free catalog
1-800-22-LYMAN
www.lymanproducts.com
475 Smith Street
Mi letown, CT 06457
Rev. 07/14