Frequently Asked Questions

1. Why can't I pre-Tin a Cast Iron surface for the smooth application of #2 bearing Babbitt?

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Tinning or pre-Tinning a surface in preparation for applying a new Babbitt bearing surface is quite common and beneficial. You can get a smoother, more consistent and longer lasting Babbitt surface. Unlike Steel bearing housings, however, it is very difficult to pre-Tin a Cast Iron surface for two reasons:

  1. The first is the porosity of the Cast Iron surface. It is difficult to remove the oxide layer from the rough Iron surface, and thus difficult to get the metal-to-metal bond between your Cast Iron surface and the pre-Tinning compound.
  2. The second issue is usually the age and contamination of the Cast Iron surface. Bearing housings were commonly made out of Cast Iron over 30 years ago. Consequently the porous Iron surface has contacted and/or absorbed hundreds of contaminants that will interfere with your metal-to-metal pre-Tinning bond.

The primary method used to remove these contaminants is heat and chemical fluxing agents. By applying a chemical flux appropriate for the temperature range of your Babbitt application (like Kapp Copper-Bond Flux™), you can remove these contaminants from the bearing housing. For a very dirty old housing, however, you have replaced the original contaminants – oil, rust, dirt, old Babbitt turnings, etc. – with the oxidation products of the fluxing action. These new contaminants can be just as disruptive to your desired bond. So, you end up applying and reapplying the flux and heat to get the Cast Iron surface clean enough to accept Babbitt or a Pre-Tinning compound. On a very old bearing housing, this can be a very long and expensive process.

One alternative to this repetitive fluxing process is to clean the Cast Iron surface with flux and then use a Pre-Tinning compound like KappaTinning™ Compound to apply an even coating of Tin to the Cast Iron surface. KappaTinning™ Compound is 50% flux solids and 50% pure Tin. The included flux removes the oxide layer and other contaminants and leaves the Tin to bond to the Cast Iron. This process has worked successfully for some customers with contaminated Cast Iron housings. This will not work, however, for old Cast Iron housings soaked with decades of oil and other contaminants. In these cases, you are better off cleaning the surface as best you can, and pouring the new Babbitt bearing surface directly into the housing. The roughness of the Cast Iron surface is sufficient to hold the Babbitt bearing surface in place for most older motor and generator setups.

While it would be ideal to have a pre-Tinned surface to accept your new Babbitt lining, this may not be possible with many older Cast Iron housings. If you find that the bearing life is significantly degraded by an inability to get sufficient Babbitt lining to stick to the bearing housing, it is probably necessary to try this procedure again or machine a new housing.

2. Do you have general soldering instructions that work with most solders?

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The following guidelines apply to most soldering operations. There are three general steps:

  1. Clean and break the oxide layer on the parts to be joined;
  2. Apply heat to the parts, not the solder; and
  3. Apply the solder evenly across the joint area and remove the heat.

More specifically:

General Soldering Guidelines

  1. Pre-clean the parent metal or metals to be joined.

    Use emery cloth, a wire brush, sandblasting, etc.

    (Prepare Aluminum surfaces with a Stainless Steel wire brush.)

  2. Apply the appropriate Kapp non-corrosive liquid flux to draw the solder into the joint/repair area. The flux also serves to remove oxide layers which prohibit strong bonding. The recommended flux is listed on each soldering alloy information page. You may easily use the rod to spread the flux.

  3. Use a soft flame, heat gun or soldering iron to heat the parent metal adjacent to the repair area. A direct flame on the repair area is likely to overheat the solder and flux.

    DO NOT DIRECTLY HEAT THE SOLDERING ROD!

  4. Hold the torch tip 4 to 6 inches away from the parent metal. If it is necessary to apply the flame directly to the rod or flux, pull the torch tip back even farther from the work surface and keep it moving.

  5. The flux will begin to bubble and turn light brown. Besides preparing the parent metal for the solder, these changes indicate the proper working temperature. If the flux turns black, let the area cool, clean it, and start over.

  6. When the flux turns brown, it is time to apply the rod. Drag the rod over the area to be soldered, until it begins to flow.

    ONCE THE ROD FLOWS, STOP APPLYING THE HEAT!

    If additional layers are needed, continue to drag the rod over the area.

  7. Sometimes it is necessary to heat the tip of the rod with the flame to help the solder flow more easily onto the repair area.

    DO NOT HEAT THE ROD TO THE MELTING POINT!

  8. Observe the solder deposit. The solder should bond smoothly.

    DO NOT OVERHEAT!

    The rod will melt if overheated, but will not bond properly.

  9. If you stopped soldering and want to apply more solder or flow out the deposit more, let it cool a little, add more flux and reheat. The flux will help the bonding process, whether adding more rod or just flowing out the previous deposit.

  10. Remove the excess flux with warm water and a wire brush.

3. What makes Aluminum and Stainless Steel soldering so much more difficult?

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Both Aluminum and Stainless Steel rapidly form a very strong oxide coating over the metal. The smooth and uniform oxide coating is what prevents these metals from corroding away except in the harshest environments. Breaking this oxide coating is thus crucial in getting the strong metal-to-metal bond between the solder and parts. The soldering instructions below apply equally to soldering Aluminum and Stainless Steel.

  1. Pre-clean the parent metal or metals to be joined. Prepare Aluminum, diecast, or Stainless Steel surfaces with a Stainless Steel wire brush. Breaking the tough oxide coating on the parts is the secret to Aluminum and Stainless soldering. These barriers reform quickly, so agitate, flux and solder in a rapid sequence.

  2. Apply the appropriate Kapp non-corrosive liquid flux to break the oxide barrier and draw the solder into the joint/repair area. You may easily use the solder rod to spread the flux.

  3. Use a soft flame, heat gun or soldering iron to heat the parent metal adjacent to the repair area. A direct flame on the repair area is likely to overheat the solder and flux.

    DO NOT DIRECTLY HEAT THE SOLDERING ROD!

  4. Hold the torch tip 4 to 6 inches away from the parent metal. If it is necessary to apply the flame directly to the rod or flux, pull the torch tip back even farther from the work surface and keep it moving.

  5. The flux will begin to bubble and turn light brown. Besides preparing the parent metal for the solder, these changes indicate the proper working temperature. If the flux turns black, let the area cool, clean it & start over.

  6. When the flux turns brown, it is time to apply the rod. Drag the rod over the area to be soldered, until it begins to flow.

    ONCE THE ROD FLOWS, STOP APPLYING THE HEAT!

    If additional layers are needed, continue to drag the rod over the area. With some applications, for example with very thin wires, it may be helpful to tin the part surface with the rod before soldering the parts together. In this case, follow steps 1 through 6 to apply an even coat of solder to the parts. Let these parts cool, and then follow steps 1 through 6 again, soldering the parts together. This will often result in a more consistent solder joint for small parts.

  7. Sometimes it is necessary to heat the tip of the rod with the flame to help the solder flow more easily onto the repair area.

    DO NOT HEAT THE ROD TO THE MELTING POINT!

  8. Observe the solder deposit. The solder should bond smoothly.

    DO NOT OVERHEAT!

    The rod will melt if overheated, but will not bond properly.

  9. If you stopped soldering and want to apply more solder or flow out the deposit more, let it cool a little, add more flux and reheat. The flux will help the bonding process, whether adding more rod or just flowing out the previous deposit.

  10. Remove the excess flux with warm water and a wire brush.

4. I have a requirement to solder battery cell tabs. 1 of the tabs is Aluminum; the other is a coated Copper sheet. What should I use to solder these components?

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You have two choices for Aluminum-to-Copper electrical component soldering:

Kapp Product % Tin % Zinc Temp Range °F Temp Range °C Product Code
KappAloy9™ 91 9 390°F Eutectic 199°C Eutectic 121
KappAloy15™ 85 15 390°F to 550°F 199°C to 288°C 124

KappAloy9™ 91Sn/9Zn solder is the eutectic standard solder for Aluminum-to-Aluminum and/or Copper. It is used extensively in oven soldering and other automated soldering systems. Its eutectic nature makes it ideal for high production automated soldering systems. In addition, it minimizes the heat applied to delicate electronic parts.

KappAloy15™ is the 85Sn/15Zn solder. In hand soldering Aluminum and Copper parts together, this solder may give you more flexibility. It has a melting range of 390°F to 550°F and 199°C to 288°C. The solder thus gives you a slushy range to manipulate your parts, before it solidifies completely during cooling. Many customers using hand-soldered for structural joints prefer this solder. It is used less often in electrical connections to minimize heating of electrical/electronic parts and potential heat damage. The general rule of thumb is less heat is always better – less distortion, less segregation, less differential cooling of different metals, etc.

For successful soldering of Aluminum parts, the oxide coating must be broken to allow the solder to form a metallic bond with the Aluminum. This oxide coating can be penetrated by scratching the Aluminum surface with a Stainless Steel brush or by using chemical flux. Both of these solders use Kapp Golden Flux™. The flux residue can be removed with warm water and a rag.

5. We are using Kapp Galvanite™ for soldering a sandwich of two Aluminum and one Copper plate. When we solder larger plates, the sandwich bows too much and we can’t use it. Do you have an alternative solder and flux?

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You are getting plate deformation because you are heating dissimilar metals. They expand and contract at different temperatures and at different rates. Our recommendation is to minimize the required heating of the parts. Use an alloy close to the eutectic solder KappAloy9™. In our customers’ experience we see two successful solders for such an application:

Kapp Solder % Tin % Zinc Temp Range °F Temp Range °C Product Code
KappAloy9™ 91 9 390°F Eutectic 199°C Eutectic 121
KappAloy15™ 85 15 390°F to 550°F 199°C to 288°C 124

Kappaloy9™ - 91Sn/9Zn solder is the eutectic standard solder for copper and aluminum plates. It is used extensively in oven soldering and other automated soldering systems. Its eutectic nature makes it ideal for high production automated soldering systems.

I included the Kappaloy15™ - 85Sn/15Zn solder for you to compare. As you are hand soldering a Copper plate to two Aluminum plates, this solder may give you more flexibility. It has a melting range of 390°F to 550°F and 199°C to 288°C. The solder thus gives you a slushy range to manipulate the parts, before it has solidified completely during cooling. Many customers using hand-soldered for structural parts prefer this solder. It is used less often in electrical connections to minimize heating of electrical/electronic parts and potential heat damage. The general rule of thumb is less heat is always better – less distortion, less segregation, less differential cooling of different metals, etc.

The flux for both of these Kappaloy™ solders is Kapp Golden Flux™. In our experience, we don’t think you will get a consistent reliable joint in any substantial production of this assembly without flux. With or without the flux, you may get a more reliable repeatable joint by pre-tinning the parts with the solder, and then reheating them with additional solder to join the plates. I realize this will consume more time, but you will get a substantially more consistent joint.

6. I would like to use Kapp Alumite™ for repairing Aluminum radiators. It appears to be the best all around Aluminum Solder. Is this the right solder for Aluminum radiator repair? What flux do I use?

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Kapp Alumite™ is designed primarily for use on a broad range of Aluminum and diecast alloys – cast Aluminum parts, white metal, and diecast car and marine parts, including propellers. It is an exceptional repair rod with a wide market for many automotive and marine applications. I am concerned, however, that Alumite™ is not the best solder for Aluminum and Aluminum-to-Copper radiator repairs.

Most Aluminum radiators are made of thin extruded and/or sheet Aluminum alloys. These alloys are best joined at lower temperatures by one of two alternative products – KappRad™ 40 or KappAloy15™. The table below compares these solders to Alumite™.

% Tin % Zinc % Cadmium Temp Range °F Temp Range °C Product Name
40 27 33 350°F to 500°F 176°C to 260°C KappRad™ 40
85 15 0 390°F to 550°F 199°C to 288°C KappAloy15™
Proprietary Lead & Cad Free 715°F to 735°F 379°C to 390°C Alumite™

KappRad™ 40 has been specifically designed for Aluminum and Aluminum-Copper radiator repair. It has higher strength and vibration resistance than comparable solders and brazing alloys, and is applied at a lower temperature to avoid damaging thin and delicate parts. It does, however, contain Cadmium - a restricted substance under RoHS guidelines. It has specific application waivers in many countries, but I am unsure of your regulations or markets. Please see the MSDS for KappRad™ 40 for more information.

KappAloy15™ is a standard solder for Copper and Brass tubes to an Aluminum sheet. It is used extensively in Aluminum-to-Copper radiator repair, where the higher strength of KappRad is not necessary, or where there are restrictions on the use of Cadmium.

Both of these solders use Kapp Golden Flux™ to remove the oxide coating in close and inaccessible joints.

In hand soldering, both of these solders give you excellent flexibility. They have wider plastic melting ranges, which allow you to manipulate your parts, before it has solidified completely during cooling. Many customers using hand-soldered prefer these solders.

7. Which product is best for repairing the galvanized coating on Steel parts after welding?

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GalvRepair™ and Lead-free Galvanite™ are the two solders designed for high quality repairs to galvanized surfaces. Both products use a similar procedure, but their slushy ranges are different.

GalvRepair™ - 30%Tin/20%Zinc/50%Lead – 350°F - 600°F / 176°C - 288°C

Galvanite™ - 50%Tin/49%Zinc/1%Copper - 390°F - 570°F / 200°C - 300°C.

GalvRepair™ has been the industry standard of galvanizing repair for over 50 years. However, more and more countries, states, and counties are requiring the switch to Lead-free products. Galvanite™ was developed specifically to meet this Lead-free challenge.

Both GalvRepair™ and Galvanite™ exceed performance standards as specified by ASTM standard A780-92 for repair of galvanized coatings. Both provide a broad slushy range for spreading and smoothing the applied solder over the entire repair area. These broad melting ranges also allow for layered application to build up the protective coating to substantial thicknesses. Please see the instructions below for more application information. The procedure is exactly the same for both repair rod formulas.

Galvanite™ MSDS

GalvRepair™ MSDS

Galvanizing Repair Instructions PDF

8. I am getting inconsistent results using KappRad™ 40 to solder Aluminum and Aluminum/Copper Radiators. Sometimes the solder flows and wets well. Other times it doesn’t wet at all and no repair holds.

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In all repairs involving Aluminum, one of the most important steps is breaking the oxide layer on the Aluminum and/or Copper parts to allow the solder to bond with the part. If you are experiencing good solder flow, but a poor joint with the part, the following soldering process should be completed in rapid succession:

  1. The parts to be joined should be brushed with a Stainless Steel brush to loosen their oxide coatings. This “scratching” of the invisible oxide coating is crucial to solder flow and bonding;
  2. If the joint area is inaccessible to scratching, or if the joint requires solder to flow into a narrow area between parts, Kapp Golden Flux™ should be applied to the joint area. The flux breaks the oxide layer and draws the solder into narrow joint areas for a much more consistent and thorough solder application. Flux is not necessary if the entire joint area is accessible to brushing and these steps are accomplished in rapid succession
  3. The parts should be heated until the flux begins to activate (boil) and turns yellow or brown. Do not overheat the flux. If the flux chars, it becomes a contaminant in your joint. Then you must allow the parts to cool and start over, ensuring all the flux residue is removed
  4. Apply the solder rod, dragging the rod through the solder pool to get solder under any oxide remaining on the parts. Do not directly heat the solder rod!

Following this procedure, you sometimes may have difficulty “starting” the solder rod. That is, the flux activates but you find that you are overheating the flux and part before you get the solder to flow. This is typically due to the oxide coating on the solder rod itself. In such cases, there are some techniques for handling the solder rod that can help promote solder flow and create a successful bond.

  1. First, the end of the solder rod should be brushed with a Stainless Steel brush to break the oxide coating on the solder rod.
  2. If the user still experiences difficulty in getting the rod to flow when heating the parts to be joined, she can heat the end of the solder rod directly with the heat source; again, to soften the solder and break the oxide barrier to flow, not to melt the solder completely. These two steps can usually break through the oxide coating on the solder rod and promote the flow necessary for a strong joint.

9. I am soldering Copper tabs to Copper wire. What is the best solder and flux to use?

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There are three decisions in determining the best solder for your Copper joint:

  1. Do you need some plastic range from the solder to allow some manipulation of the joint as it solidifies? The electronic industry standard for Copper-to-Copper electrical/electronic joints is KappZapp3.5™. It is 96.5% Tin - 3.5 % Silver. This eutectic solder melts and solidifies at the same 430°F / 221°C. It is used most often in automated soldering of electrical connections to minimize heating of electrical/electronic parts and potential heat damage. The general rule of thumb is less heat is always better – less distortion, less segregation, less differential cooling of different metals, etc.

    However, the single melting/solidifying temperature makes repositioning the wires during soldering and cooling difficult. You either overheat the solder/flux, or you are forced to reheat the joint, which weakens the bond. Alternatively, 96% Tin / 4% Silver solder has a plastic range of 430°F to 475°F (221°C to 246°C). This allows for some manipulation of the parts without substantially overheating the joint. Your choice depends on how you jig the parts for soldering, and whether you need to adjust the parts during soldering/cooling.

  2. The second questions is do you need a flux to break the oxide later on your parts and flow the solder into tight, aka capillary, joints?

    The appropriate flux for either solder wire above is Kapp Comet Flux™. It is used on non-Aluminum joints in the temperature range of 350°F to 550°F. Its MSDS is included below.

    Alternatively, KappZapp3.5™ solder is available with a Rosin Solder Core for electrical/electronic soldering. This simplifies the soldering process by applying the flux to the joint area using the same solder rod. The flux flows before the solder, removing the oxide layer only in the joint area, and only just as it is needed. This Rosin-Cored solder is used most often in hand soldering electrical/electronic parts.

  3. The third question that must be answered is whether you need a higher strength solder joint in the final use of your components. For example, the speaker industry standard is KappZapp7™. This solder is used extensively by audiophiles and the speaker industry to join Copper wire to speaker tabs in high vibration setups. This is only recommended where the higher strength is necessary because you are heating the parts to higher temperatures of 430°F to 575°F (221°C to 302°C).

    The appropriate flux this higher temperature Silver solder is Kapp Copper-Bond Flux™. It is used on non-Aluminum joints in the temperature range of 550°F to 800°F. Its MSDS is included below.

    Alternatively, KappZapp7™ solder is available with a Rosin Solder Core for electrical/electronic soldering. This simplifies the soldering process by applying the flux to the joint area using the same solder rod. The flux flows before the solder, removing the oxide layer only in the joint area, and only just as it is needed. This Rosin-Cored solder is used most often in hand soldering electrical/electronic parts.

KappZapp™ MSDS

Kapp Comet Flux™ MSDS

Kapp Copper-Bond Flux™ MSDS

General Soldering Instructions PDF

10. I am soldering Copper tabs to Copper wire in an automotive sound system. What is the best solder and flux to use?

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The speaker industry standard for high-end audio/visual and speaker installations is KappZapp7™. This solder is used extensively by audiophiles and the speaker industry to join Copper wire to Copper speaker tabs in high vibration setups. This is only recommended where the higher strength is necessary because you are heating the parts to higher temperatures of 430°F to 575°F (221°C to 302°C).

The appropriate flux for this higher temperature Silver solder is Kapp Copper-Bond Flux™. It is used on non-Aluminum joints in the temperature range of 550°F to 800°F. Its MSDS is included below.

Alternatively, KappZapp7™ solder is available with a Rosin Solder Core for electrical/electronic soldering. This simplifies the soldering process by applying the flux to the joint area using the same solder rod. The flux flows before the solder, removing the oxide layer only in the joint area, and only just as it is needed. This Rosin-Cored solder is used most often in hand soldering electrical/electronic parts.

KappZapp™ MSDS

Kapp Copper-Bond Flux™ MSDS

General Soldering Instructions PDF

11. I am looking for a Lead-free auto body solder that works well on older steel that can’t handle the heat of a MIG welder.

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Our Lead-free Galvanite™ is easy to work with and provides a strong bond in body repair and seam buildup. It comes in a rod form - .200” x .250” x 14” long. Galvanite™ has a broad slushy range of 390°F to 570°F (200°C to 300°C). When heated, the slurry can be shaped and spread easily to blend seamlessly with existing Steel surfaces. In many repair projects, the Steel surface is prepared with a Stainless Steel brush. Then, the same Stainless Steel brush or a putty knife is used to spread and even out the Galvanite coating as it cools. The Galvanite coating can be built to a substantial thickness, even on vertical surfaces.

12. Does Kapp Alloy & Wire, Inc. accept small orders directly from consumers?

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Yes, we do deal directly with end users. We cover the higher cost of smaller orders three ways. First, there is a $10/order small order charge for orders of less than 10 pounds. Second, we offer volume discounts for higher volume orders. For an example at current metal prices, 3 lbs of Galvanite™ - 50% Tin / 49% Zinc / 1% Copper – would be $22.10/lb + shipping. Fifty (50) pounds of the same material would be $14.58/lb + shipping. This is a volume discount of over $7.50/lb. Third, we only accept small orders paying with VISA and MasterCard. This decreases the administrative cost of checks and PayPal payments.

13. I am attempting to solder together Stainless Steel and Copper wires. The Tin-Lead solders we have do not have the strength, temperature range or ductility we need in the final part. What solder should we use for soldering these dissimilar metals?

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Stainless Steel is usually non-magnetic and often has a dull brushed silver finish. Stainless Steel alloys with high Nickel or Chromium contents can be very shiny and have a mirror finish. These highly polished alloys are much more difficult to solder due to a very strong oxide layer. They typically require the oxide layer to be physically broken by wire brushing or sanding, AND chemical removal of the oxide layer by acid flux.

Your need for a higher temperature range, as well as higher strength and ductility leads you to KappZapp™ Tin/Silver solders. Which Tin/Silver alloy is best for your Stainless Steel to Copper joints is usually determined by four criteria:

  1. Strength/Vibration Resistance
  2. Electrical Conductivity
  3. Cost, and
  4. Rosin Flux-Cored, Acid Flux-Cored or Solid Wire

As the chart below illustrates, strength, vibration resistance and electrical conductivity all go up with an increase in the Silver (Ag) content of the KappZapp™ solder. The price also increases with the Silver Content. So the challenge is to choose the solder that meets your needs without buying more Silver than you need.

Composition 96.5Sn - 3.5Ag 96Sn - 4Ag 93Sn - 7Ag
Solidus(°F) /(°C) 430°F / 221°C 430°F / 221°C 430°F / 221°C
Liquidus(°F) /(°C) 430°F / 221°C 475°F / 246°C 570°F / 299°C
Tensile Strength (copper) 14,000 psi 14,000 psi 15,500 psi
Tensile Strength (stainless) 25,000 psi 28,000 psi 31,000 psi
Shear Strength 11,600 psi 12,000 psi 14,000 psi
Elongation 48% 49% 49%
Electrical Conductivity (%IACS) 16.4 16.5 20.1

Finally, you must choose between solid wire, Acid and Rosin Flux-Cored wire. The flux-cored wires are the easiest to use because the flux for removing the oxide layer from the parts is enclosed in the center of the wire. When the parts are heated to the melting temperature of the solder, the flux flows out and breaks down the oxide layer. This allows a strong metallic bond between the solder and the parts in one step. When using solid solder wire, the oxide layer on the parts must be broken by physical agitation with a Stainless Steel brush or sandpaper, or by a separate liquid or paste flux.

To begin your solder selection, choose between the solid wire KappZapp™, Acid-Cored KappZappA™ and Rosin-Cored KappZappR™ solders:

KappZapp™ Solid Wire Solders - Silver Solders for Stainless to Stainless and/or Copper Electrical/Electronic Connections

KappZapp™ Silver solders produce very strong and ductile joints on Stainless and Copper wires and connectors. The resulting joints have high tolerance to vibration and stress, with tensile strengths to 15,500 psi on Copper, 31,000 psi on Stainless. KappZapp7™ - 93% Tin - 7% Silver is the industry standard for speaker and home theater industries with high conductivity, strength and vibration resistance. KappZapp™ solid wire comes in 3.5%, 4%, 5%, 6% and 7% Silver.

KappZappR™ Rosin-Cored Solders – Self-Fluxing Silver Solders for Copper Electrical/Electronic Connections

KappZapp™ Rosin-Cored solder can produce strong and ductile joints on Stainless Steel and Copper without requiring additional liquid or paste flux. The internal natural rosin flux is released on heating to remove the oxide layer on the parts. The resulting joints have high tolerance to vibration and stress, with tensile strengths to 31,000 psi on Stainless Steel. KappZappR™ comes in 3.5% and 7% Silver formulas.

KappZappA™ Acid-Cored Solders – Self-Fluxing Silver Solders for Copper Electrical/Electronic Connections

Some high Nickel and Chromium Stainless Steels require acid flux to break through the tough oxide layer on the parts. KappZappA™ Acid-Cored solder can produce strong and ductile joints on Stainless Steel and Copper without requiring additional liquid or paste flux. The internal acid flux is released on heating to remove the oxide layer on the parts. The resulting joints have high tolerance to vibration and stress, with tensile strengths to 31,000 psi on Stainless Steel. The acid flux is more aggressive than the natural Rosin flux, and must be removed completely by wiping with a wet rag after soldering. KappZappA™ comes in only the 3.5% Silver formula.

Solder Diameter and Packing Selection

Once you have determined the right solder, the diameter and quantity of solder necessary for your project must be determined. Common wire diameters are 1/18" (.125" = 3.2mm), 1/16" (.062" = 1.6mm), and 1/32" (.031" = 0.8mm). The diameter of wire is usually based on the size of the joint surface area. The smaller the joint, the smaller the necessary solder diameter will be.

To provide a quotation, Kapp Alloy needs to know

  1. The total quantity you need,
  2. the alloy you need,
  3. whether you need a rosin flux-core, acid flux-core or solid wire,
  4. the diameter of the wire you need, and
  5. the package (for example, 1 lb spools, 5 lb spools or 18" sticks.