Buyer’s Guide to Metric Dowel Pins

dowel pin

7 Things to Know When Buying Metric Dowel Pins

This guide is a follow up to our Dowel Pin Buyer’s Guide published May 2017.  This post is specifically written to share with you the available options when it comes to procuring precision Metric dowel pins.

Our goal is to help simplify the buying process and guide you in the critical selection factors for this sometimes complex and confusing category of fasteners.

1. What standards are Metric Dowel Pins made to? 

Metric dowel pins are tricky because they fall into two buckets:

  1. DIN / ISO standard – These metric Dowel pins are readily available in the commercial marketplace and in addition to your suppliers, can be procured through national catalogers like Mcmaster-Carr, Grainger and Holo-Krome. They come on steel and stainless steel.
  2. Precision Metric Dowel Pins – These “Precision” dowel pins are manufactured by precision component brands such as Pic Design, WM Berg and Unicorp who have their own technical specifications and are not governed by DIN or ISO standards. They are usually only offered in stainless steel through distributors of precision components.

2 . What are the specific criteria I can select for Metric dowel pins?

Here is a list of the criteria and available options available:

  • Size
  • Material
  • Hardened or Unhardened
  • End style
  • Tolerances

3 . Can you list the standard and precision dowel pins available off the shelf?

4. Which types of metric dowel pins are available in which sizes and materials? 

Use this handy grid to understand the sizes and materials available in each Metric dowel pin style.

Standard
Ends
Materials
Tolerances / Fit
Hardness
Diameters
DIN7
ISO 2338
ISO 2338A
Rounded or beveled 
Steel (least common)
300 Series Stainless Steel including
A1=18-8, 303, 304
A4=316
M6 diameter tolerance
Slightly Oversized
aka Press Fit
Unhardened
M.8-M20
ISO 2338B
Rounded or beveled
300 Series Stainless Steel
A1=18-8, 303, 304
H8 diameter tolerance
Unhardened
M1.5-10
DIN 6325
DIN 6325H
ISO 8734A
ISO 8734
Rounded on one end
Beveled on one end
Alloy Steel
M6 diameter tolerance
Slightly Oversized
aka Press Fit
Hardened to
RHC 52-62
M1-M25
Precision Unhardened
Rounded
300 Series Stainless Steel
M6 diameter tolerance
Slightly Oversized
aka Press Fit
Unhardened
M1-M12
Precision Hardened
Rounded on one end
Beveled on one end
416 Stainless Steel
M6 diameter tolerance
Slightly Oversized
aka Press Fit
Hardened to
RHC 36-42
M2-M10

Important note:  All pin options may not be available in all sizes and materials.

5. When ordering, do I need to specify the dowel pin tolerance or call out attributes such as standard, undersized or oversized fit? 

Metric dowel pins can show up under DINs and ISO numbers, including : DIN 7, DIN 6325, and ISO 2338 and 8734. When ordering DIN/ISO dowel pins it is best to include the Diameter, Length, Material, DIN or ISO and tolerance.  For non DIN/ISO Precision metric dowel pins, you can order by the manufacturer part number, such as Pic (MDP series), WM Berg (DM Series), or Holo-Krome.

6. Can I specify if I need radius (round) or chamfer (bevel) on the pin ends?

The pin style will depend upon the spec and the material. Precision dowel pins may come with either a double chamfer, double radius, or a radius on one end and a chamfer on the other end.  Check with the handy grid above for guidance.

Important note:  The configuration of the ends of unhardened metric dowel pins are at the discretion of the manufacturer.  If you have a specific style requirements, you might need to special order which usually involves a minimum and a lead time.

7. What if I need domestic or DFAR certified Metric dowel pins? 

If you are ordering by a Precision Manufacturer part number, you are in luck!  Most of the stainless steel pins produced by Pic, WM Berg and Unicorp qualify as DFAR compliant and full certifications with material certs and test reports are often available for USA made parts for a fee.

Metric Dowel Pins at MF Supply

We offer:

  • The full range of commercial Metric Dowel pins including parts that are USA made, DFARS and ROHS compliant.
  • Metric sizes including ASME ANSI B18.8.2, DIN 7, DIN 6325, and ISO 2338 and 8734
  • Metric Precision Dowel pins including Press-Fit Series and all MD series pins in 416 and 303 Stainless Steel.
  • Brand names and generic equivalents.
  • Custom-made parts per print in non-standard sizes and exotic materials and finishes.
For more detailed information about Metric Dowel Pins, to request a line card, or to send an RFQ, visit our website. And if you don’t see what you need listed, as always, ask us. “Finding the right screw for you” is our tag line after all!
Contact me at robin@mfsupply.com with your questions, comments or helpful hints!

About Us

For more than 40 years, MF Supply has helped American manufacturers streamline operations, saving them time and money with our sourcing expertise and unique supply chain strategies. We are a WBE/WOSB certified stocking distributor of fasteners and electronic components.

We work with the best-established factories in the United States and DFARS-certified countries, and stock a huge inventory including all major brands and equivalents. MF Supply provides solutions including: same-day drop ship direct from the factory; custom sizes, materials and plating options; and DFARS parts with full paperwork and Certificates of Conformance.

We creatively solve common problems including hard-to-find parts and long lead times. Our sourcing and reworking expertise includes fast turnaround for modification of existing parts, hard to find standards and specials, special threads, non-standard diameters and lengths, exotic materials, special platings and short runs. We provide functional equivalents to expensive brand name fasteners and help our customers save money while reducing lead times.

Follow our blog at http://mfsupplyblog.wordpress.com/


Smart Manufacturers Use Blanket Purchase Orders to Reduce Risk

Learn to Hedge Against Inflation through Proactive Purchasing

 

The world of manufacturing is filled with risks. Staff turnover, overseas competition and third party vendor issues can all threaten your service level and put pressure on your organization. But one of the biggest risks in 2018 is inflation.

 

Rising material prices and inflationary forces are impacting costs at every level. Master suppliers are reporting price increases of 7%+ on steel products and 10%+ on stainless steel. What is a manufacturer to do?

 

One of the most powerful ways to mitigate the risk of rising prices is through a proactive supply chain strategy that includes issuing Blanket Purchase Orders (BPO). With a stable price for a fixed period of time, the BPO serves as a hedge against inflation.

 

  1. What is a Blanket Purchase Order?

A blanket Purchase Order is a contract to buy parts at a guaranteed price within a specific time period or schedule (typically one year). For example, a manufacturer forecasts to use 10,000-12,000 pieces of an MS16555 stainless steel dowel pins annually. They issue their supplier a Blanket PO for 12,000 pins a year at a negotiated price with 12 monthly releases of 1,000 pieces. This gives them 12 months of predictable costs at today’s 12,000 piece price, rather than tomorrow’s 1000 piece price. As we start to see double digit price increases in the industrial marketplace, the savings multiply.

 

  1. What are the benefits of Blanket Purchase Orders?

A Blanket PO can add certainty to a business and can make your production process leaner, guaranteeing the price and availability of parts without the burden of holding the parts in stock. Suppliers also benefit because they have a predictable revenue stream. Both sides have certainty concerning quantity, price, delivery requirements and payment terms.

 

Beyond certainty, the top benefits of BPOs for manufacturers are:

  • Reduces unit costs through quantity discounts.
  • Guarantees pricing & reduces time spent on price negotiation.
  • Shortens lead time and eliminates stock outs.
  • Assurance of quality of products and vendors.
  • Improves efficiency of ordering, receiving and bill paying process.
  •  Leaner operations with reduced stock burden.

 

During inflationary times, the benefits of locking in today’s prices for up to 1 year multiply.

 

  1. When should a manufacturer issue a Blanket PO?
  • When an item has a high minimum annual usage ($500 minimum EAU).
  • When a quantity discount can be achieved.
  • When you are already making repetitive purchases from the same supplier within a certain time period (typically 1 year).
  • When parts are used according to a production schedule.
  • When parts have a lead time.
  1. When should a manufacturer NOT issue a Blanket PO?
  • When minimum annual usage of item is low (under $500).
  • When part is only used for project work and usage in unpredictable.
  • When price is subject to change without notice.
  • When quality of product or supplier is questionable.

 

  1. What other factors should I consider?

The main risks when using Blanket Purchase Orders occur when BPOs are not monitored or extended past their final scheduled release, which can lead to price changes and inventory availability problems. The best way to mitigate this risk is through the use of an effective spend management tool that includes a minimum safety stock level. Collaboration with your supplier is also recommended.

 

The other main risk occurs when a blanket order is issued for more than the needed quantity of a specific part due to demand forecast issues or product changes. This risk can be mitigated by working with your supplier to set conditions to manage this gap, such as extending a 1 year blanket to 18 months.

 

Blanket Purchase Orders at MF Supply:

Here at MF Supply, we can help you effectively craft a proactive BPO strategy based on your organization’s unique needs. We offer blanket orders for up to 18 months with flexible terms and low minimums.

 

For more detailed information about Blanket Purchase Orders, to request a line card, or to send an RFQ, visit our website. And if you don’t see what you need listed, as always, ask us. “Finding the right screw for you” is our tag line after all!

Contact me at robin@mfsupply.com with your questions, comments or helpful hints!

 


Buyer’s Guide to Mil-Spec Fasteners

MS24693C

7 things you need to know

If you sell to the military either directly or indirectly, then you are probably familiar with Mil-spec fasteners. But, what exactly are they and what should you know before buying them? We’d like to help you out with this Seven point buyer’s guide.

  1. What does Mil-spec mean anyway?

Mil-spec or MIL-STD, is the informal name for the military standard the U.S. Department of Defense uses in the production of military equipment. Critical fasteners and components used in the production, repair and maintenance of this equipment are classified as “Mil-spec” fasteners. These parts are usually designated by an AN, MS, NAS or NASM prefix followed by a part number (i.e. MS24693C-4). Each of these prefixes is an abbreviation: for example: NAS stands for National Aerospace Standard and MS stands for Military Standard.

  1. What’s the difference between Mil-spec and commercial fasteners?

Mil-spec fasteners look a lot like their civilian cousins, but these little guys are made to a specific standard that defines in detail, the screw’s attributes, including: dimensions, tensile strength, hardness, threads, drive type, material qualities and plating, just to name a few. Mil-spec fasteners are even traceable by lot to designated manufacturers. The government maintains a list of factories that are qualified to manufacture and distribute Mil-spec fasteners. These suppliers have met all the government’s requirements and pass the highest quality control standards. This designation is called Qualified Suppliers List for Manufacturer’s [QSLM]. Commercial fasteners are not held to such specific and exacting standards.

  1. Who uses Mil-Spec Fasteners?

Mil-spec fasteners are used by anyone manufacturing or servicing military equipment. How do you know if your project requires Mil-spec parts? Often, the bill of materials (BOM) calls for specific Mil-spec grade fasteners in accordance with a part number, drawing, NIIN or NSN or procurement requirement. Some of the most common uses of Mil-spec fasteners include aerospace and naval vessels.

  1. Do Mil-Spec fasteners have different features and standards than commercial fasteners?

Mil-spec parts are manufactured and tested to strict military standards ensure performance and reliability. In general, commercial fasteners will not have the same exacting quality standards. Let’s look at a specific example and compare the Mil-Spec MS24693-C4, which is a 4-40 x 3/8 Phillips Flat 100 degree Machine screws in 300 series stainless steel, to its commercial cousin.

Features of the MS24693C-4:

  • ­  Manufactured in an QLSM approved factory
  • ­  Made/melted in the USA or other DFARs* approved country
  • ­  Materials to procurement spec FF-S-92, SAE AIR 4127
  • ­  Cleaned, descaled, passivated to AMS-QQ-P-35; AMS 2700
  • ­  Dimensions, tensile, hardness, threads, recess, head marking to AN, MS, NAS, NASM standard
  • ­   Magnetic permeability to test specs ASTM A342
  • ­  Quality Assurance to procurement spec FF-S-92 MIL-STD 1312
  • ­  Inspection system requirements per Mil-I-45208
  • ­  Full lot traceability, manufacturer’s certification and chemical and physical certification
  • ­  Available in diameters from #0 through 1/4 inch in coarse and fine thread and various lengths

 

Features of a 4-40 x 3/8 Commercial Phillips Flat 100 degree Machine screws in 18-8 series stainless steel:

  • ­ Manufactured per ASME B18.6.3-2002
  • ­ Thread dimensions to ASME B1.1

 

As you can see, the Mil-spec version is held to a higher and more exacting level of quality and testing than the commercial version. As such, the Mil-spec parts are cleaned and passivated, and tested for magnetic permeability, whereas the commercial parts are not.

 

5.   What level of certification is required?

Generally, a Certificate of Conformance (COC) or a record affirming a fastener has met the requirements of the relevant specification, contract or regulation is sufficient for Mil-Spec fasteners. Full certifications, which include the part name, part description, date of manufacture, lot number, chemical composition of material, and treatment of material including plating or passivation, and material test reports, are often available for a fee. It is critical to ask for the level of certification (COC, full material certs, passivation certs, etc) in advance in order to have the most efficient buying experience.

6. Are there other factors to consider when procuring Mil-spec fasteners?

Great question! Almost a decade ago, the term “DFARS Compliant Material” came to the forefront for companies supplying parts and services to the government. The original Federal Acquisition Regulation (FAR) clause 252.225-7014 specified “A Preference for Domestic Specialty Metals.” What that means in our world is that for fasteners to be DFARS compliant, the metal used to fabricate them must be melted or manufactured in the United States or a qualifying country.

Qualifying countries include: Australia, Austria, Belgium, Canada, Czech Republic, Denmark, Egypt, Finland, France, Germany, Greece, Israel, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, United Kingdom of Great Britain and Northern Ireland.

Important Note: DFARS only pertains to fasteners made from “specialty metals” including: stainless steel, high alloy steel like Grade-BD, or Grade 5 Chromium steel with high chromium content.

To keep up to date with DFARs requirements, visit www.acq.osd.mil/dpap/dars/dfarspgi/current/index.html

  1. Where can I find a list of Mil-spec fasteners and specs?

The Defense Logistics agency is a great resource. They maintain a comprehensive database of specifications and drawings. They also maintain a catalog of hardware that includes NIINs and NSNs that sometimes called out in a bill of materials. Check out the following links for more comprehensive information regarding hardware:

http://www.dla.mil/TroopSupport/IndustrialHardware/  – to view catalogs of mil-spec parts and specs by category

http://quicksearch.dla.mil/qsSearch.aspx   – To look up a specific part

http://www.mfsupply.com/mil-spec-fasteners-s/1823.htm – To see MF Supply’s Mil-Spec fastener stock

http://www.mfsupply.com/v/vspfiles/assets/images/MFSUPPLY_MILITARY.pdf – To download MF Supply’s Mil-spec line card

 

For more detailed information about Mil-Spec parts, to request a Mil-Spec Line Card or to send an RFQ, visit our website. And if you don’t see what you need listed, as always, ask us. “Finding the right screw for you” is our tag line after all!

Contact me at robin@mfsupply.com with your questions, comments or helpful hints!


Standoffs and Spacers Buyer’s Guide

standoffs and spacers mf supply

7 things you need to know

According to the dictionary, a standoff is defined as “a stalemate or a deadlock between two equally matched opponents and a spacer is a piece of material used to maintain space between 2 things.   In the world of precision manufacturing, standoffs and spacers are mechanical components that are used the create space or join parts together, typically in PC boards.  Below are 7 things to know to have the most efficient buying process.

  1. What are spacers and standoffs?

Often classified as Electronic or Panel Hardware, Standoffs and Spacers are commonly used to mechanically support and electrically connect and position components within assemblies, typically in PC boards and instrument panels.

  1. What’s the difference between a standoff and a spacer?

Both standoffs and spacers have a hex or round shaped body, and 2 openings.  The main difference is that spacers are unthreaded with an inside clearance hole, and standoffs are threaded on both ends.  Threads may be male (external) r female (internal).

  1. Who uses standoffs and spacers?

Look inside an assembled circuit board, and you will be greeted by a bevy of Standoffs and Spacers, because in the world of Electronic Hardware, they are the standard for connecting and mounting circuit boards, panels, doors, and gears. Both are commonly used to properly position parts within an assembly, to reduce component contact, to elevate stacked sections, to ensure enough room for heat to dissipate, and to separate or create space between two objects. These guys are workhorses!

  1. What materials and platings are available?

Common materials include aluminum, brass, plastic/nylon and stainless steel. Common platings include clear anodized, nickel, gold iridite and zinc plated. There are over 20 common platings available! Here is a guide to most common materials:

  • Aluminumis popular because of its ratio of weight to strength. It is light, non-magnetic, performs well in severe temperatures, and has insulating properties.
  • Brassis used in making high-quality standoffs. It is conductive, resists corrosion, and is non-magnetic. It is costlier and heavier than aluminum and is usually plated zinc or nickel.
  • 18-8 Stainless Steelis strong, conductive, nonmagnetic and offers excellent corrosion resistance.
  • Nylon 6/6is superlight, nonconductive, and resistant to chemicals and solvents.

316 stainless steel, alloy and other exotic materials, and special diameters and lengths are available in certain sizes and/or for special order and usually involve a lead time.

  1. What sizes are available off the shelf?

Standard stock sizes run from 3/16 – 1/2 body diameter, 1/4 to 2” long with threads starting at 2-56 running through 1/4-20 and clearance holes ranging from #2 though 1/4”. Metric stock sizes run from M3.5-M6 body diameter with M2.5, M3 and M4 threads.  Remember, the lengths and threads available depend upon the diameter of the body and not all size configurations will be available.

As always, special lengths and sizes are available – just ask!

  1. What information should I provide to get an accurate quote?

The easiest way to order is by manufacturer part number.  If you don’t have one, you’ll need to specify body diameter, body shape (hex or round), body length, thread size & gender (male or female), material and plating.  For example, a popular standoff size is a 1/4 hex x 1/2 Long x 10-32 male Standoff in Stainless Steel.

  1. Are there other factors to consider?

YES! One surefire way to save money and shorten delivery time is to cross the OEM brand part on your bill of materials to a functional equivalent.  Popular brands include: Amatom, Concord, Globe, H.H. Smith, Lyn-tron, Microplastics, Keystone, Pem, RAF, Unicorp.

Finally, standoffs and spacers sometimes show up under their Mil-spec numbers, which can be crossed to commercial equivalents. Some common Mil-spec series include NAS42, NAS43, NAS61, NAS1056, NAS1057, NAS1829, NAS1831. Where applicable, these Mil-spec parts will be DFAR compliant with full paperwork.

Contact me at robin@mfsupply.com with your questions, comments or helpful hints!


Buyer’s Guide for Using Functional Equivalents to OEM Brands

5 Things to Know when Comparing Fastener Brands to Generic Alternatives

This year, we’ve discussed how the trademarked brand Keensert® is often available as a Mil-Spec or generic branded key-locking insert. We also reviewed how national brands of precision shoulder screws, such as Amatom, Concord, RAF and others are also offered by McMaster-Carr (tight tolerance series), MSC, Grainger and generically.

But how exactly do you determine which categories of fasteners cross to generic alternatives? This guide offers creative solutions including when to cross, and how to save money and reduce long lead times by using brand alternatives.

1.  What is a functional equivalent when it comes to fasteners and precision components?  

You can find hundreds of registered trademark-branded fasteners and components in the industrial marketplace. Much like brand-name pharmaceuticals such as Tylenol and Advil are available generically (as acetaminophen and ibuprofen), some brand name fasteners are also available as “generics,” “crosses,” “alternatives” or “functional equivalents.”

In the world of fasteners, a functional equivalent fastener is a part that is the same as the brand-name product in form, fit and function, including material and plating specifications.

2.  How can I determine if I must use the brand name or if I can cross to a generic part?

Before you shop, check the bill of materials to see if it specifically calls out a particular brand name along with the part number. If no specific manufacturer’s name is listed, then you can typically use a functional equivalent.

Use this handy 4 point checklist as your guide:

  • Does your bill of materials specifically call for the OEM brand-name fastener or component?
  • Can you live with the lead time or will having parts sooner improve delivery of the final product?
  • Will your supplier provide a certificate of conformance?
  • Will saving money help you be more competitive?

3.  What categories of fasteners are available as generic or functional equivalents?

Popular categories include adhesives and sealants, anchors, bits and nutsetters, cage nuts, flex type lock nuts, handles, Keenserts, knurled thumb screws, nylon insert stop nuts,  precision shoulder screws, retaining rings, rivets & blind threaded inserts, self-clinching, fasteners, spacers and standoffs, speed clips, spring nuts, weld nuts, weld studs, and woodworking screws.

4.  What brands of fasteners should I consider crossing to their generic or functional equivalent?

A sample list of brands that have generic alternatives: 

3 STAR RIVETS USA, ABBATRON®, ALCOA, AMATOM®, APEX®, ARCONIC®, ATLAS®, AVDEL®, AVK®, B. F. GOODRICH, BOLLHOFF, BUCKEYE, CAPTIVE, CELUS®, CHERRY®, CONCORD, FASTENAL, GESIPA®, GRIPCO®, GLOBE ELECTRONICS, H. H. SMITH, HUCK, INDUX, INTERFAST, KEYSTONE, LOCTITE®, LYN-TRON, MACLEAN­ESNA®, MARSON®, MCMASTER-CARR, MISUMI, MSC INDUSTRIAL, PEM®, PIC DESIGN®, POP®, POWERS®, QUICKSCREWS, RAF, RED HEAD®, ROTOR CLIP®, SHEREX, SIMPSON, SOUTHCO®, SPS TECHNOLOGIES, TINNERMAN®, U. S. ANCHOR. VIP, W. M. BERG, W. W. GRAINGER, WALDES TRUARC®.

5.  What are the advantages of using functional equivalents?

Brand names are great, and when they are in stock, available and required by your customer, then you can buy them with confidence in their quality. However, one surefire way to save money and shorten delivery time is to cross the OEM brand part on your bill of materials to a functional equivalent.

Brands and Functional Equivalents at MF Supply

Supplying a full range of fastener products and services, MF Supply is an authorized distributor of Amatom/Carey, Captive (Pem equivalent), Chrislynn Inserts, Concord, EZ-Lok, Lok-mor, Lyn-tron, Microplastics, Shear-loc, S&M Retaining Rings, and Unicorp, as well as a distribution partner for many others. We have an expertise in dowel pins, inserts and Keenserts and domestic and Mil-Spec products.

We provide functional equivalents to expensive brand name fasteners and help our customers save money while reducing long lead times. Check out our recent case study where a functional equivalent was substituted for an OEM brand, reducing costs by 37% and shaving lead time. This time and money savings gave the manufacturer an advantage over their competition, which helped them win the job.

For more detailed information about brands we commonly cross, visit our website. And if you don’t see it listed, as always, ask us. “Finding the right screw for you” is our tag line after all!

MF Supply is a WBE/WOSB certified stocking distributor of precision fasteners and electronic components, specializing in precision hardware including precision shoulder screws. For more than 40 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.


Dowel Pin Buyer’s Guide

dowel pin

 8 Things to Know When Buying Dowel Pins

If you are a manufacturer working with complex assemblies or fixtures, then you’re likely very familiar with precision dowel pins. Commonly used as a hinge, shaft or pivot to locate or hold assembled parts together, dowel pins can withstand frequent insertion and removal without distortion. They are broadly used across various applications in many industries, including: aerospace, electrical motors, hydraulic equipment, instrumentation, tooling and fixtures, machinery, military and many more.

Our goal is to help simplify the buying process for this sometimes complex and confusing category of fasteners.

1. What is a precision dowel pin? 

Dowel pins are solid, headless cylindrical shaped straight metal pins with a centerless ground finish. Manufactured to precise fractional diameters and lengths, dowel pins come in a variety of sizes, styles, designs and materials. This variability can cause confusion among buyers, engineers and end-users alike.

2. What materials and platings are available?

Precision dowel pins are available off the shelf in alloy steel (typically hardened) and stainless steel grades 18-8/303, 316 and 416 (typically hardened). Other exotic materials or special finishes are available for special order with a lead time.

3. What sizes are available?

Standard sizes include inch from 1/16″ to 1″ diameter, and metric from M1 to M20 diameter. Length options vary by diameter. Other diameters and special lengths are available for special order and usually involve a lead time.

4. When ordering, do I need to specify the dowel pin tolerance or call out attributes such as standard, undersized or oversized fit? 

Precision dowel pins often show up under their MIL-SPEC numbers, MS16555, MS16556 and Mil-P-21143. Metric dowel pins might show up under the following DINs and ISO numbers: DIN 7, DIN 6325, and ISO 2338 and 8734. Dowel pins might also show up under a manufacturer part number such as Pic, WM Berg, Unbrako or Holo-Krome. If you are ordering by MIL-SPEC, manufacturer’s part number or DIN, then the general attributes including tolerance and style are known. Here are a few of the other options that will help you order the correct pin:

The most common standard inch or imperial sized precision dowel pin is made to the ASME ANSI B18.8.2 spec and has a diameter tolerance of -0.00 / +0.0002 and length tolerance of +/-0.010. For example, a ¼” (0.25) diameter standard dowel pin will have a diameter between 0.2500–0.2502″.

The standard metric tolerance is related to the DIN. Both DIN 7 and DIN 6325 have a standard m6 diameter tolerance of +0.012mm / +0.004mm and a length tolerance related to the specific pin length.

Undersized series dowel pins are used for inconsistent holes. They have a basic diameter 0.0002″ under the nominal diameter. For example, a ¼” (0.25) diameter undersized dowel pin will have a diameter between 0.2500–0.2498″. The Mil-P-21143/2- falls into the undersized category.

Important note:  All pin options may not be available in all sizes and materials.

Finally, the Oversized series of dowel pins are usually used to fit into worn holes and are generally used in the aftermarket for repairs. These pins are only available off the shelf in steel in a small range of sizes.

5. Can I specify if I need radius or chamfer on the pin ends?

The pin style will depend upon the spec and the material. Precision dowel pins may come with either a double chamfer or a radius on one end and a chamfer on the other end. Specific style requirements are available for special order and usually involve a lead time.

6. What information do I need for ordering?

The easiest way to order is by either the manufacturer or MIL-SPEC part number. To order by description, you need the diameter, length and material and if applicable, and any special tolerance, plating or style requirements.

7. Do I need to buy special installation tools?

Just remember, no hammers! When installing dowel pins, never drive the pin into the hole with force. Always press it in for best results. And production favors pins since they require no extra fastening hardware for insertion, no secondary operations, and no mating parts. This ease-of-use adds up to speedier production, which makes everyone in the food chain happy!

8. What level of certification is required?

Generally, a Certificate of Conformance or a COC is sufficient for your customer. Full certification with material certs and test reports are often available for USA made and MIL-SPEC parts for a fee.

Dowel Pins at MF Supply

We offer:

  • The full range of commercial and MIL-SPEC parts, including parts that are USA made, DFARS and ROHS compliant.
  • Brand names and generic equivalents.
  • Custom-made parts per print in non-standard sizes and exotic materials and finishes.
  • Inch and metric sizes including ASME ANSI B18.8.2, DIN 7, DIN 6325, and ISO 2338 and 8734
  • Metric Precision Dowel pins including Press-Fit A, B and Slip-Fit C series and all MD series pins in 416 and 303 Stainless Steel.

For more than 40 years, MF Supply has helped American manufacturers streamline operations, saving them time and money with our sourcing expertise and unique supply chain strategies. We are a WBE/WOSB certified stocking distributor of fasteners and electronic components.

We work with the best-established factories in the United States and DFARS-certified countries, and stock a huge inventory including all major brands and equivalents. MF Supply provides solutions including: same-day drop ship direct from the factory; custom sizes, materials and plating options; and DFARS parts with full paperwork and Certificates of Conformance.

We creatively solve common problems including hard-to-find parts and long lead times. Our sourcing and reworking expertise includes fast turnaround for modification of existing parts, hard to find standards and specials, special threads, non-standard diameters and lengths, exotic materials, special platings and short runs. We provide functional equivalents to expensive brand name fasteners and help our customers save money while reducing lead times.

Follow our blog at http://mfsupplyblog.wordpress.com/


Case Study: Smart Manufacturers use Brand Equivalents to Save Time and Money

Newsletter
Volume 20
March 7, 2017

In our January blog we discussed how Keylocking Inserts are often referred to by their trademarked brand name Keensert®.  The Keensert® is not alone! Did you know that many brand name OEM fastening products and components can be crossed to a generic alternative equivalent product?

Before you shop, check to see if the bill of materials specifically calls out a particular brand name. If no specific manufacturer’s name is listed, then you can typically use a functional alternative or equivalent.   Using equivalents and alternatives to OEM brand names can be a smart way to reduce long lead times and/or cut expenses.

Check out this Case Study where an OEM brand was substituted with a functional equivalent, reducing costs by 37% and shaving lead time.  This time and money savings gave the manufacturer an advantage over their competition, which helped them win the job.

Little Known Ways to Save 37% and Shorten Delivery Times
 
ISSUE
Display Manufacturer is bidding on a job where the bill of materials calls for 15,000 pieces of an 8-32 x .312 brass insert by SPIROL®. SPIROL® has 265 local stock, 5000 due in 10 days, balance in 4-5 weeks. Based on this delivery schedule, the Display Manufacturer cannot meet their prospective client’s two week delivery requirement.

SUGGESTED SOLUTION
MF Supply gets a print of the part from SPIROL® and is able to cross it to an exact functional equivalent for an alternative brand we distribute and our factory has in stock. Samples of the alternative fasteners are delivered directly to the customer within 24 hours for inspection and testing.

The alternative sample fasteners are approved for production by the Display Manufacturer within 2 days. The prospective client approves the substitution and awards the manufacturer the business.  A Purchase Order for the inserts is issued to MF Supply. Within 48 hours, the complete 15,000 inserts are available from the factory and delivered to the Display Manufacturer.

TIME SAVINGS
-MF Supply functional equivalent fasteners shorten delivery time from 4-5 weeks to 2-3 days.

COST SAVINGS
-SPIROL® Price = .11938 each. Total cost $1790.
-MF equivalent price = .075 each. Total cost $1125.

SUMMARY / BENEFIT
-Cost savings of $665 or 37%.
-Display Manufacturer wins bid and is awarded job.
-Work is completed on time.
-Job is more profitable due to cost savings realized on fasteners.
-Job has been a repeater and a money maker for Display manufacturer.

In summary, if your bill of materials calls for an OEM brand fastener or component, find out if you must have the brand name product.  In cases where a generic or equivalent alternative part will work, there might be an opportunity to save money and shorten delivery time.

For more information about MF Supply contact:

Robin Lieberman, President
robin@mfsupply.com
973-777-5411


Keensert® Buyer’s Guide

Keensert® Buyer’s Guide

5 Things You Need to Know

If you are a precision manufacturer working in high-torque and high-temperature situations, you might already be familiar with Keensert® key-locking inserts.  Common uses include thread repair applications or to provide thread durability in situations such as aerospace assemblies, electronic equipment and suspension units.

But, what exactly are they and what should you know before buying them? We’d like to help you out with this quick buyer’s guide.

  1. What is a Keensert®?

A Keensert® is a solid bushing style insert that is threaded on both the inside and the outside, and has wedges or “keys” attached at the top. They are generically called key-locking inserts, and are used to distribute loads and repair or strengthen threads against failures due to stripping, seizing or corrosion.

Although the name Keensert® is often used generically (like Band-Aid® or Kleenex®), Keensert®  is the registered trademark of Huck Patents (its close cousin, the Keysert® is a registered trademark of Alcoa Fastening Systems.).

Before you shop, check to see if the bill of materials specifically calls out Huck or Alcoa brand as the Keensert®  manufacturer. If no specific manufacturer’s name is listed, then you can typically use an alternative like Rock Solid brand, a generic equivalent or cross to a MIL-SPEC part.  This becomes important due to price and availability of the brand name parts.

  1. What materials and sizes are available?

Keenserts are available off the shelf in 303 stainless steel or carbon steel. Standard diameters are: American #6-32 to 1 ½” and Metric  M4 to M24. Other diameters (starting at 2-56 and M2) and materials (including 316 stainless steel, and alloys 4140 and A286) are available for special order and usually involve a lead time.

  1. What information do I need for ordering?

To order, you’ll need the manufacturer’s part number or the internal and external thread and material. Alternatively, key-locking inserts often show up under their MIL-SPEC numbers, which can often be crossed to commercial equivalents. Common MIL-SPEC numbers include: MS51830, MS51831, MS51832, NAS1394, NAS1395, NA0146, NA0147, NA0148, NA0149, NA150, and NA0151.

  1. Do I need to buy special installation tools?

When purchasing key-locking inserts, check with your production department to make sure you have the tools you need to properly install inserts. You can buy kits that include a tap, drill, and installation tool.

  1. What level of certification is required?

Generally, a Certificate of Conformance or a COC is sufficient. Full certification with material certs and test reports are often available for a fee.

In summary, in order to have the most efficient Keensert shopping/buying experience, be prepared with the following information before you shop:  Do you need the Alcoa or Huck brand product or can you use a generic or MIL-SPEC alternative?  Make sure to have the manufacturer’s part number, MIL-SPEC part number or the internal/external thread and material.  Do you need an installation tool? Finally, check to see if you require a standard COC or full certs.

For more information about MF Supply contact:

Robin Lieberman, President
robin@mfsupply.com
973-777-5411

 


What the heck are Precision Shoulder Screws?

Newsletter

Volume 8

July 23, 2014

What the heck are Precision Shoulder Screws?

Here we go again, with our “what the heck is that” series, where we discuss some of the unique fasteners and electronic hardware that manufacturers use in the design and assembly of their products. Today, we will introduce you to the Shoulder Screw.

What is a Precision Shoulder Screw? 

Shoulder Screws, which are sometimes called Shoulder Bolts or Stripper Bolts, are (generally) hex socket screws with an enlarged, unthreaded cylindrical shoulder under the head.  They are comprised of 3 main parts: the head, the shoulder and the thread.  They come in two basic categories, “Commercial” and “Precision”.

Commercial Shoulder Screws are made to inch standard ANSI ASME B18.8.2.  The size range for the shoulder diameter is from ¼ to 2”.  The thread class is 3A and the tolerance on the shoulder is +.005 /  -.005.

Precision Shoulder screws are sometimes referred to as “tight tolerance” shoulder screws. They are not governed by any official ANSI or ASME standard.  The size range for the shoulder diameter is from 3/32 to ½.  The thread class is 2A and the tolerance on the shoulder diameter varies from +.000/-.001 to  -.0005 to -.0015 depending upon the manufacturer.  Now that’s precise!

Who uses Shoulder Screws?

Just as Dowel Pins and Retaining Rings are used to locate or hold parts together within a precision assembly or a fixture, so are Precision Shoulder Screws.

Yet shoulder screws are more versatile.  When installed, the unthreaded shoulder acts as a shaft for rotating items such as bearings and bushings, precision spacing, machinery support, and motion guiding.   Precision Shoulder screws exacting tolerances make them ideal for use with other precision components.

They are broadly used across various applications in many industries, including: aerospace, electrical motors, hydraulic equipment, instrumentation, tooling and fixtures, machinery, military and many more.

What do I need to consider when selecting Shoulder Screws?

Although Shoulder Screws are offered in a multitude of materials and styles, when it comes to the main commercial and precision offerings, there are a few main issues to consider.

Which Drive and Head Style?

Precision shoulder screws are readily available in hex socket and slotted drives.  Philips drives are available in certain sizes.  Torx and Star are available for special order.  Typical head styles are a modified fillister with a flat top where the head diameter is about twice the head height.   Low head fillisters are available in certain sizes

Which material do I need?

Precision shoulder bolts are readily available in Type 18-8/303 Stainless Steel and 416 Stainless Steel.  316 Stainless Steel, Alloy and other exotic materials are available for special order.

Are there other factors to consider?

When ordering Precision Shoulder screws, specify the Shoulder Diameter, Shoulder length, thread size, material and drive type. For example, an example of a typical Precision Shoulder screw is a ¼ shoulder x ½ long x 10-32 thread in SS18-8 with a hex-socket drive.  Non-locking is the most popular style, but locking may also be available.

Precision Shoulder Bolts  often show up under their brand name.  Some of the most popular brands include: BERG, Concord, Globe, PIC, Lyn-tron and RAF. A comprehensive selection of Shoulder Screws is also offered by McMaster-Carr (tight tolerance series), MSC and Grainger.

Finally, Precision Shoulder Screws can also show up under their Mil-spec numbers, which include MS51575 & MS51576 and are DFARS compliant with full paperwork.

Precision Shoulder Screws at MF Supply

We offer:

The full range of commercial and mil-spec parts, including parts that are DFARS and ROHS compliant.

Brand names and generic equivalents.

Custom made parts per print in non-standard and exotic materials and finishes.

Inch and Metric sizes.

For more detailed information on Precision Shoulder Screws, visit us at http://www.mfsupply.com/SearchResults.asp?Cat=1922

And if you don’t see it listed, as always, ask us. Finding the right screw for you is our tag line after all!

 


What the heck is Mil-spec DFARS?

MS24693C

Welcome to the second edition of our “What the heck is that” series, where we discuss some of the unique fasteners and electronic hardware that manufacturers use in the design and assembly of their products.  If you sell to the military either directly or indirectly, then you are probably aware of today’s topic:  “DFARS” and “Mil-spec fasteners”.

What does Mil-spec mean anyway?

Before we get into the nitty gritty of DFARS, let’s discuss what makes a “Mil-spec” fastener.   Mil-spec is the informal name for the military standard the U.S. Department of Defense uses in the production of military equipment. For example, the MS24693C pictured above is a fastener produced according to military standards.

Mil-spec fasteners look a lot like their civilian cousins, but, these little guys are made to a specific standard that defines in detail, the screw’s attributes, including: dimensions, tensile strength, hardness, threads, drive type, material qualities and plating, just to name a few.  Mil-spec fasteners are even traceable by lot to designated manufacturers.  The government maintains a list of factories and suppliers who are qualified to manufacture and distribute Mil-spec fasteners.  These suppliers have met all the government’s requirements and pass the highest quality control standards. This designation is called Qualified Suppliers List for Distributors [QSLD] and the Qualified Suppliers List for Manufacturer’s [QSLM].

 

AKA – Also known as…..

Mil-spec fasteners are usually designated by an AN, MS, NAS or NASM prefix followed by a part number.  Each of these prefixes is an abbreviation: NAS stands for National Aerospace Standard and MS stands for Military Standard.  An example of one of the most common and popular Mil-spec machine screws is the MS24693C.  Its commercial equivalent is a Phillips Flat 100 degree Machine Screw in 300 series stainless steel.  Below, we’ll tell you more about this popular fellow.

Who uses Mil-spec Fasteners?

Mil-spec fasteners are used by anyone manufacturing or servicing military equipment.  Often, the bill of materials calls for specific Mil-spec grade fasteners in accordance with a part number, drawing or procurement requirement.  Some of the most common uses of Mil-spec fasteners include aerospace and naval vessels.

Now, tell me about DFARS…

Almost a decade ago, the term “DFARS Compliant Material” came to the forefront for companies supplying parts and services to the government. The original Federal Acquisition Regulation (FAR) clause 252.225-7014 specified “A Preference for Domestic Specialty Metals.”  What that means in our world is that for fasteners to be DFARS compliant, the metal used to fabricate them must be melted or manufactured in the United States or a qualifying country.

Qualifying countries include: Australia, Austria, Belgium, Canada, Czech Republic, Denmark, Egypt, Finland, France, Germany, Greece, Israel, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, United Kingdom of Great Britain and Northern Ireland.

Important Note:  DFARS only pertains to fasteners made from “specialty metals” including: stainless steel, high alloy steel like Grade-BD, or Grade 5 Chromium steel with high chromium content.

To keep up to date with DFARs requirements, visit www.acq.osd.mil/dpap/dars/dfarspgi/current/index.html

section 252.225

An example of a DFARS Mil-Spec Screw please!

As we’ve learned, the MS24693C is actually Phillips Flat 100 degree Machine screws in 300 series stainless steel.   The MS24693-C4 is a 4-40 x 3/8 Phillips Flat 100 Degree Machine Screw in 302 Stainless Steel, and it is one of the most widely used sizes.  Interestingly, the MS24693C superseded the AN662C series, so you might come across the AN662C on an older print of bill of materials.  Keep in mind, with any design or manufacturing decision, the reason for using a specific screw generally rests in the hands of engineering.

Features of the MS24693C

–  Strict military standards ensure performance and reliability

– Made/melted in the USA or other DFARs-approved country

–  Materials and dimensions meet Federal standard FF-S-92

–  Inspected per Mil-I-45208

– Full lot traceability, manufacturer’s certification and chemical and physical certification

–  Available in diameters from #0 through 1/4 inch in coarse and fine thread and various lengths

Lessons Learned: Considerations when purchasing MS24693C or other Mil-spec DFARs fasteners

  • Always ask for “full certifications”.  This includes part name, part description, date of manufacture, lot number, chemical composition of material, and treatment of material including plating or passivation.
  • At point of purchase, make sure the screws are DFARS.  If you do not specifically ask for DFARS-compliant screws, you might receive screws that don’t meet the DFARS requirements, in which case, they won’t meet military standards.  We’ve learned this the hard way so hopefully you don’t have to!

MS24693C and other Mil-spec DFARS Fasteners in Stock at MF Supply

Here at MF Supply, we stock some of the most common Mil-spec Fasteners, including the following: Machine Screws, Socket Screws, Hex Head Cap screws, Nuts, Flat washers and Standoffs and Spacers.

Visit us at www.mfsupply.com/v/vspfiles/assets/images/MFSUPPLY_MILITARY.pdf for our military linecard.

For more detailed information on Mil-spec Fasteners, visit us at www.mfsupply.com/SearchResults.asp?Cat=1823

And if you don’t see it listed, as always, ask us.  Finding the right screw for you is our tag line after all!

About MF Supply
For over 35 years, MF Supply has been a trusted supplier of Fasteners and Electronic Hardware to OEMs, machine shops, manufacturers, and assemblers of machines and instruments in New Jersey, the greater NYC Metropolitan area and beyond.   We are wholesale only.

– Phone: 888-972-7397 [888-9-SCREWS]

–  Email: sales@mfsupply.com

–  Online: www.mfsupply.com

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