Frequently Asked Questions and Plug Tips
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Frequently Asked Questions
Ball Plugging Tips
321 Pro-Plug/Ultima Quick Troubleshooting Guide
321 Pro-Plug/Ultima Ball Plug Comparison

What causes plug to chip/crack and how can I prevent it from happening?
  Two main reasons plug will chip and crack are: room temperature above 80EF, and/or the plug mass is too large, generating too much heat during cure.

A temperature of 72E-78°F (this applies to the room, chemical and ball) must be obtained for the plug to cure properly. Large holes should be plugged in two stages, allowing the first half of the plug to cure completely before plugging the second half of the hole. This will prevent excess heat being generated by too much plug material.

What are the causes of plug curing too slow, and what can be done to insure a solid cure?
  Slow curing plug is caused by defective pumps, plug that hasn't been mixed long enough, room temperature below 70EF or small masses of plug that don't generate enough heat to provide a thorough cure. The following are solutions to these examples:

1) Test and replace pumps if necessary (See the Pump Test Procedure, below.
2) Mix the plug for a full two minutes. Use a stop-watch if necessary.
3) Make sure the room temperature is between 72E-78°F.
4) When plugging small holes, mix the plug and leave in the cup until the plug becomes very warm. Pour immediately into the hole.

Can I plug large holes without the plug cracking?
  Plug the hole in two stages. Plug one half of the hole and let it cure completely. After this plug is hard and cool to the touch, plug the second half of the hole. This is especially true for large holes in urethane balls, since the thicker shells of urethane balls tend to trap heat. This procedure helps prevent too much heat from being generated by the plug and causing it to crack.
How can I make sure that my pumps are dispensing the correct amount of material?
  Use the following Pump Test Procedure:
1) Use two identical cups
2) Dispense 1 plunge of compound into one cup
3) Dispense 3 plunges hardener into second cup
4) Place cups side by side on a level surface
5) Fluid levels in the cups should be identical
6) If the fluid is not at the same level, the pumps are not dispensing the proper amount of material. Replace pumps to avoid plug curing problems.
What can I do to reduce air bubbles in the plug?
  Air bubbles usually indicate that the plug has been mixed too vigorously. Mix the plug slowly in a figure eight pattern, occasionally scraping sides and bottom of the cup. Do not pour plug into the center of the hole; this procedure tends to trap air bubbles at the bottom. Pour the plug slowly, using the stir-stick as a guide so the plug runs down the wall of the hole.

If air has already been entrapped while mixing, allow plug to stand in the mixing cup for approximately ten minutes. The larger surface area in the cup will allow the air bubbles to escape more easily.

How can I prevent a plug from shrinking after its been cut down and finished?
  Plug will shrink after being cut down or finished because it has not completed the curing process. The frictional heat created when finishing the partially cured plug causes a secondary reaction and swelling in uncured epoxy. The plug then shrinks as it cools. This usually occurs in cold weather or when plugging smaller holes.

To prevent this from happening, place a 60-75 watt light 3-4" away from plug material for 1-2 hours immediately after the plug is poured. This will prevent shrinkage in cold weather. When plugging smaller holes, leave plug in the cup until it becomes warm, then pour in the hole.

What causes separation between the plug seam and ball, and how can I prevent it from happening?
  Plug separation is caused by the interior of the hole not being completely clean or by improper or inadequate plug mixing. Clean the hole's interior surface with a fast drying solvent such as acetone before plugging. This help's insure good adhesion. For proper mixing, follow manufacturer's instructions. Light sanding near the top of the hole will also help create a better adhesion.
Is it safe to use heat lamps to cure plug in cold weather?
  Yes, if care is taken not to overheat the plug. If heat lamps or other heating devices are used, be certain not to leave them unattended.
Is it safe to mix regular 321 Pro Plug compound with Ultima hardener and vice versa?
  Mixing two different types of plug is not recommended. Curing problems may occur due to the difference in formula.
Do I have to get new pumps if I'm switching ball plug, or can I just take the pumps out of the old ball plug and put them in the new?
  Again, this is not recommended. New pumps should be purchased to avoid the possibility of an incorrect ratio between compound and hardener.

Ball Plugging Tips

1. Maintain a room, ball and chemical (ball plug and color kit) temperature of 72° to 78°F. Since ball plug is temperature sensitive, it is very important to maintain this temperature.

2. Mix plug slowly for two minutes in a figure eight pattern. Occasionally scrape the sides and bottom of the cup to insure that the plug is mixed thoroughly.

3. Use a stop watch or clock to time the amount of stirring. It is important that the plug be mixed for two full minutes to complete the reaction of the compound and hardener.

4. When coloring the plug, add the color to the compound only. Add the hardener after the color has been matched to the ball. This will prevent over mixing or having the plug cure before a color match is made.

5. Plug large holes in two stages. Plug one half of the hole and let it cure completely. After this plug is hard and cool to the touch, plug the second half of the hole. This procedure helps prevent too much heat from being generated by the plug and causing it to crack.

6. When plugging small holes, mix the plug and leave it in the cup until the plug becomes very warm, then pour immediately into the hole.

7. Allow the plug to cure completely before routering and sanding. This helps prevent the plug from shrinking after the plug has been cut down.

8. Pour excess uncured plug into miniature ice cube trays for later use. When the plug cures, use the "cubes" to fill large holes. The plug cubes will not affect the curing of the liquid plug.

9. When preparing a ball to be plugged, drill out any bevel or large cracks around the perimeter of the hole. This will increase plug adhesion and reduce the possibility of edge chipping or separation. Lightly sanding near the top of the hole will also help create better adhesion.

10.Read and follow all manufacturer's instructions on the label of the bottle. This applies to ball plug and color kits.

DBA 321 PRO-PLUG and ULTIMA Ball Plug
Quick
Troubleshooting Guide

Problem

Cause

Solution

Slow cure, will not harden Incorrect 3:1 ratio; plug not mixed long enough; room temperature below 70° Test pumps; mix plug for two full minutes; increase room temperature.
Shrinkage Plug cut down before completely cured Place light source 3-4 inches away from plug material for 1-2 hours immediately after plug is poured.
Chipping, cracking, brittleness Too much heat; curing too fast; mass of plug too large; too much hardener Remove external heat source; reduce room temperature below 80°F; verify correct 3:1 ratio
Air bubbles Plug mixed too vigorously Mix slowly in a figure eight pattern
Separation along seam of ball and plug Improper or inadequate mixing; interior of hole not completely clean Follow manufacturer's instructions for proper mixing; cleaninterior or hole with fast drying solvent; lightly sand near the top of hole
Cloudiness in clear plug Curing too fast; too much heat Remove external heat source, verify correct 3:1 ratio
Edge chipping Bevel of finger hole not drilled out or cleaned prior to plugging Remove the bevel on the hole by drilling with a bit slightly larger than thehole; clean hole with a solvent cleaner
Voids in plug Curing too fast; vigorous mixing Pour ball plug into the hole while still completely liquid; discard plug if it starts to gel or cure in cup; mix less vigorously

DBA 321 Pro-Plug and DBA Ultima Ball Plug Comparison

Plug Characteristics

DBA 321 Pro-Plug

DBA Ultima

Brand "x"

Mixing ratio 3:1 3:1 3:1
Cure time 5-7 hours 8-10 hours 8-10 hours
Gel time 63 minutes 33 minutes 47.5 minutes
Gel temperature 158°F 160°F 151°F
Peak temperature 324°F 188°F 201°
Weight per gallon Resin: 9.402
Hardener: 8.521
Resin: 9.259
Hardener: 8.503
Resin: 9.603
Hardener: 8.350
Versatility For use in all bowling balls For use in all bowling balls For use in all bowling balls
Curing process Slow, gradual Fast, tapering off after gel time Slow, gradual
Color matching ability Excellent Excellent Excellent
Shelf life 18 months 18 months 18 months

DBA Products Company
525 West Laketon Avenue
Muskegon MI 49443 USA
E-mail: dbaproducts@dbaproducts.com
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