Here's a
Black Match method that works good for me:
For Shell Cross
Match and Passfires:
Use 7 strands single filament cotton (tea bag string) or 4 strands of cotton crochet string
(size 10) for cross
match. Pull through glass eye dropper with a .100” opening.
Also, try a single strand of fuzzy 4-ply soft cotton yarn.
For Shell Leader
Match:
Use 6 strands of cotton crochet string (size 10) pulled through modified oval frosting nozzle or
2 strands of fuzzy 4-ply soft cotton yarn. The yarn or string should be lightly dampened with alcohol to give the strands additional weight and reduce surface tention for easy immersion into the
match paste.
Formulas:
For cross
match BP with willow charcoal is preferred. The binders are 2% Gum Arabic and
2% dextrin to equal a total of 4%. The BP paste is wetted with 50% water by weight.
The Gum Arabic/Dextrin must be mixed with cold water then heated to obtain a solution.
For leader
match a straight 4% Dextrin is added together during the ball milling process.
Option: Try milling the cross
match BP with Gum Arabic/Dex binder and then heating it together with the water in the double boiler.
Batch Method Procedure:
Heat the
match paste in double boiler and ladle a scoop of hot slurry into a stockpot or large coffee can. The
match paste binders are stirred with the right amount (50%) of cold water.
This is heated until the binders dissolve, then the water/binder solution is mixed with the BP.
The binders also prevent the potassium nitrate leaching out while the
match while drying.
Dampen the cotton with a little alcohol then unreel several yards into the stockpot or coffee can while alternately ladling in more hot
match paste. The best stockpot shape should be tall and narrow as opposed to flat and wide. Pat down the cotton after each addition to make sure it’s completely saturated with the paste. Keep repeating until all the cotton is unreeled then pull it through an orifice while winding it back onto the frame.
How Much To Make:
Determine size of
match frame and number of windings on the frame with spacing of say 1/2” to 5/8”. A frame +++ by +++ will accept a total of +++ turns with 5/8” spacing. This will total +++ separate pieces. The weight of BP needed to coat a single 3-foot piece of cross
match is 8 grams. Ten grams is needed for a 3-foot piece of leader
match. This amount BP is calculated so that some excess slurry is available during the application process. This is necessary to ensure all the cotton gets coated.
Match Frames:
Douglas Fur molding 1.500 by .750 varnished with “L” brackets to reinforce corners. A .625 wood dowel works for a bearing axle. Overall frame size 2 feet wide by 3 feet long. Having one frame for cross
match and the other for leader
match is a good idea.
Problems:
Don’t twist the strands of cotton in the pot of
match paste; just lightly pat it down. One of the worst problems that can occur with the batch method is having the coated strands tangle while pulling them through the orifice (sizing die) or when winding it on the frame.
Make sure all areas of the
match frame that are exposed to the
match paste are covered with wax paper. Mercerized cotton crochet string works ok at best, the tightness of the weave doesn’t allow the slurry to soak in as well as soft untreated cotton.
Edited by Pyro-pal, 27 December 2005 - 04:06 AM.