Measuring Bearings. For any even number lug bolt pattern (4, 6, 8, etc. 31496") The M10, about 10 mm in diameter, (. Replacing a hex bolt is still somewhat confusing among a lot of DIY mechanics. You may search for your product based on diameter by selecting a measurement on the Size dropdown. 1 Subaru Outback wheel specs and tire sizes (2004 – 2009) 3. Excellent for sizing bolts, screws, nuts (USS, SAE and Metric) and twist drills. Most wallpaper is priced and selected in single roll quantities but will ship in double roll bolts (hyper link to s/r d/r video). and 3 ft long. It can accommodate both the 5-100 millimeter bolt pattern, and the 5-114. 4 cm / 254 mm - find those measurements in the blue "Length" column and look to the right on that same row to see that the US men's size is 8. Textron's line of Torx-head bits and screwdrivers are designed to be used specifically with Torx-head screws. You measure the diameter of the shaft to come up with the "M5" value. Use a tape measure or ruler and measure across the gasket from the 9:00 position to the 3:00 position. Ultimate Handyman 1,497,053 views. Yep, you can say use a 5/16ths wrench on a 8mm bolt head, but you can't screw a bolt with metric threads into an SAE hole without damaging one or both. As a general rule, you would want to subtract 1/8″ off the length of the barrel for the barrel to be able to expand and lock the material together. How to Measure Fastener Length Fastener length is measured from where the material surface is assumed to be, to the end of the fastener. The closest you can get is to measure from the center of one lug to the outer edge of the lug farthest away. Measure the distance between the "Thru Bolts" on the motor that attach to the wet end/pump. Download our handy Euro Cylinder Measurement Template to simplify the measurement of euro cylinders. Choosing Latches For Your Door Handles or Knobs. Countersunk screws (Flat or Oval head) are measured by overall length. Measuring a Bolt / Screw; Measuring a Bolt / Screw. Standard S. In the above example, 1/2 inch is the shank's diameter. Rear spacing or back spacing is the distance from the backside of the wheel mounting pad to the outside of the rim flange. Select your vehicle to find the bolt pattern and the centre bore size. It does have a 10. 550 dimension may be a bit misleading. Wrap the tool around the bar and match the starting line with the size line. The length of the shank is from the point where it meets the head to the opposite end. including correct size bolts and screws. Extensive data on Metric bolt properties is here, and the same site's home page gives links to a lot of other materials, analysis, and fastener data. Dodge Bolt Patterns usually consists of only 5, 6 and 8 lug bolt patterns. Nut dimensions are maximums per SAE. 3) measure the diameter of spline or straight shaft. First you need to include the depth of your headboard leg. For example a size of 12x1. as you are going to use bolt and stud to connect flanges. Place the O-ring on a clean, flat, level surface. The diameter of this circle is known as the bolt circle diameter (BCD) or pitch circle diameter (PCD). 1 Know Rough-In Measurements and Standards. Then measure the bolt hole. Measuring Specific Types of Fasteners. With the end of the measuring tape in place, draw the tape to the very tip of the bowl and note the seat's length on a piece of paper. In this article, I have covered Flange Bolt Chart and Flange Stud Size. Perfect for measuring overall and useable length for fasteners and more. Manufacture And Distribute Metalwork and Fixings – Fast! Whether you need just one item fabricated, a thousand or even multiple contracts, B. How to Measure Wheel Bolt Pattern Also called bolt circle, bolt pattern is an expression of the number of wheel studs and the distance between them. Choosing a Headboard Height. This provides a certain amount of play in the holes, which compensates for small misalignments in hole location or assembly, and aids in the shop and field entry of fasteners. Most foreign made lenses and shutters produced after 1945 use the Metric system of threads and. If you are traveling and checking your tongue weight each time, you can make it easier on yourself by purchasing a tongue weight scale. The block is a 91 302 roller, carbed that will be dropped into a 68 coupe. The socket the bolt uses does not determine the bolt size! This is really important and a common mistake made. Ring size chart: Or, if you don't like to use our ring sizer you can use our ring size chart. hex heads and cap heads (that's allen heads) , don't include the head. If you have an old toilet with 4 bolts, measure to the rear ones. Guide to Fastener Sizes. For instance, the truck 12-bolt uses a smaller inner pinion-bearing (1. Cubic Kilometer (km 3) A Cubic Kilometer (abbreviated km 3) is a cube that is 1 kilometer on each side. Since the length of the bolt is the last. 5 wheel bolt pattern. The bolt pattern of a wheel is defined by two numbers: the number of bolt holes and the diameter of the circle (in inches) that they form, measured through the centers of the bolt holes. Taps looks like bolts and are used to thread holes. Wheel Bolt Pattern Also called bolt circle, bolt pattern is an expression of the number of wheel studs and the distance between them. Already a leader in the bifold door industry, Schweiss Bifold Doors continues to bring new quality products to our customers with the introduction of the "One-Piece" line of custom built hydraulic swing doors. Quick and Dirty Exhaust System Math. 25 millimeters between its threads. It easy to get a driveshaft that fits perfectly. Round this number to 140. including correct size bolts and screws. What is the Diameter of the Bolt / Screw? Measure this using a vernier if possible - if you are using a ruler do your best to measure outside of the threads. Expert advice from Bob Vila, the most trusted name in home improvement, home remodeling, home repair, and DIY. 3 Bolt Hole with a 10" Center Hole. Murv bolts are always referred to by the size of the threaded bit and not the spanner size, makes things very confusing, especially nowadays where for example an m10 bolt would normally have a 17mm head now it can have a 15 or a 16mm head! So in your case the 13mm may be an M8 and the 18mm an M12. How to measure Bolt Circle Diameter (BCD) Bolt Circle Diameter or BCD is the diameter of the circle that goes through the center of all of the bolts on your chainring. The bolt chart provides both US and metric stud sizes. We stock tons of axle shafts for most rear-wheel drive cars and light trucks. Hex Head Bolt Dimensions ASME B18. UNF (fine thread pitch) has more threads per inch than the same diameter bolt in the UNC (coarse thread pitch). Calculate the “Measurement Over the Wires” 1) Multiply the Thread Pitch in Millimeters by 1. To measure a 3 bolt, or lug, wheel you need to imagine a circle that passes thru the center of all three bolts. Thread Size. SIZE DIAM ETE R HEX KEY SIZE 6605 N. Measure across the flats or just try different size wrenches on it. I will try and find a 16mm socket tomorrow and hopefully that will work. In this article, I have covered Flange Bolt Chart and Flange Stud Size. This will give you the diameter of the circle in which the bolt pattern resides. A bolt pattern of 4x100 indicates a 4 bolt pattern on a circle with a diameter of 100mm. These holes are tapped with the correct size of threads for the job at hand. Measure Wheel Size. For fasteners where the head usually sits above the surface such as hex bolts and pan head screws, the measurement is from directly under the head to the end of the fastener. A "chord foot" is 12 inches measured along the chord, inside the bark, from "sapwood to sapwood," or from "heartwood to heartwood. Additionally the bend type must also be given to avoid problems in specifications of semi-round bend shapes. This is called the major diameter and will usually be the proper size of the bolt. You could move up/down a size if you wanted to. 3/8 of an inch is. Here's how to plan and post a perfect pergola. To calculate wrench size you measure across the flat surfaces of the nut or bolt, then pick a wrench marked with that size. To determine the minimum bolt length required for the standard toggle, add the thickness of the fixture, including any spacers or shims plus the thickness of the base material and the wing clearance. 5mm and that is the bolt size. com has a good slideshow that walks you through each of the areas that should be measured. Measure US and Metric thread pitch, special notch gauges, flat headed metal and wood screws. Printable sheets for a variety of auto and truck applications. Round your measurement down to the nearest standard rough-in. Getting the correct measurements is critical for purchasing pieces for a construction project or to replace attachments in a preexisting mechanism. The diameter of that circle is the measurement. We stock tons of axle shafts for most rear-wheel drive cars and light trucks. As a general rule, you would want to subtract 1/8″ off the length of the barrel for the barrel to be able to expand and lock the material together. Determine the maximum torque according to bolt (nut) size and grade. Because of their size, the pythons. Inches are measured threads per inches. U-bolts are selected based on diameter, width, and length. To measure the diameter of screws and bolts, you measure the distance from the outer thread on one side to the outer thread on the other side. 3mm 58mm 45. 0mm 58mm 34. Measure the amount of the neck bolt that extends up into the neck pocket, and mark your drill bit (a piece of masking tape around the bit works great) so that it will drill into the neck to that depth. Hex bolts are measured from under the head to the tip of the bolt. The bolt circle is most difficult and confusing dimension to measure and understand for most people. Diagram 3 Diagram 4 Backspacing Backspacing, or offset, is the distance between the back. Measure the largest outside-outside distance between the two bolts. With rotational torque, the object is free to rotate. I DID try and measure it but it is a bit tough to do with the deck still on and get an accurate measurement. What is the Diameter of the Bolt / Screw? Measure this using a vernier if possible - if you are using a ruler do your best to measure outside of the threads. 1 Know Rough-In Measurements and Standards. In this case a thousand board foot log or tree scale is assumed to be the equivalent of 100 bolt-feet, or a quantity of staves that would make 10 barrels. Install fork cap bolt and tighten to 60-70 ft-lbs. A protruding part may make a direct measurement of the bolt circle diameter impossible even with 4-bolt crank, which has holes directly opposite one another. 562 in = 9/16". Measuring fasteners is surprisingly simple. Usain Bolt Flies on Big Stride Angle. For reference, the image above illustrates how bolt circle measurements are calculated for other bolt patterns. The pattern is measured in inches or millimeters and is displayed as the number of lugs times the diameter of the circle. 5" 14 Bolt - Rear Axle To determine the ring gear diameter you need to measure the outside diameter of the. If there is an EVEN number of lugs: Measure center-to-center on lugs directly across from each other. How to Determine NPT (National Pipe Thread) Size Male NPT is denoted as either MPT or MNPT Female NPT is either FPT or FNPT Pipe thread sizes do not refer to any physical dimension. Here are the steps to measure a hex bolt for replacement. Ideal for any measuring tasks with. For nuts, size will appear as diameter and pitch. Men’s Size Chart: Conversion, Size Guide + How to Measure ( EASY ! ) What size am I? On this site you will find Men’s Sizing Charts, Converter from and to US-sizes and an easy guide on how to measure. BTW, if you are upgrading your cranks, there is no rule that you have to stay at the same size. Kirk, Unkl Ian, was right on, with his info. length, gauge, head style (for example, flat head), type of drive (for example, slotted or Phillips) and increasingly by style of screw. Girth measurements will give you additional valuable information to assess the progress of your bodybuilding program. Measure the diameter of your fan blade from the tip of a blade to the tip of the another blade in opposite direction. The thread pitch of a bolt is the difference between threads measured in Step 3 - Measure Length of Bolt. I'm also not able to (even though its fun to try) guess the size by feeling it through a 3"x3" opening. A cotter pin (USA usage) or split pin is used to keep the clevis pin in place. "AN" (Army-Navy) sizes were established by the Aerospace industry years ago. Standard hole sizes for bolts are made 1/16-in. The second number tells us the diameter of the circle created by the bolt holes. This new tester can test both digital and analog, and can test signal level by channel (both audio and video), carrier to noise ratio, and mains voltage. Then measure from edge to edge to get the overall width of the wheel. Already a leader in the bifold door industry, Schweiss Bifold Doors continues to bring new quality products to our customers with the introduction of the "One-Piece" line of custom built hydraulic swing doors. Differential Info: What did it come from? Does it have u-bolts or straps and (4) bolts, or does it have a flat plate (3-bolt / 4-bolt / 6-bolt) 3. Whitworth tools can be difficult to identify. 56 bolts opened up to a. NOTE: Both bolts a & b are of the same hardware measurement 1/2-16x2 = (1/2" shaft diameter - 16 threads per inch x 2" shaft length). 75 between the threads and is 30mm long. How to Measure Wheel Bolt Pattern Also called bolt circle, bolt pattern is an expression of the number of wheel studs and the distance between them. Calculating the offset of a wheel is a fairly easy mathematical equation. wheels, rims, aircraft tires and more for agricultural and non-highway use. Also referred to as the "lead" which is the distance a screw will advance during one turn. The bolt pattern is also known as the Pitch Circle Diameter or PCD. So a 5mm bolt will have a thread diameter measurement of something like 4. 3 Bolt Rim. When you are on the verge of procuring a new toilet, use a straight edge or sight down the back of the toilet to estimate where the wall would be. Round your measurement down to the nearest standard rough-in. It is very common that these will rust and require replacement over time. Below are a number of common fasteners with a graphic of the proper measurement area. First, measure from the center of the right bolt hole to the center of the left bolt hole located on the back of the seat area. The measurement is then cross referenced to a size number known as a wire gauge size. Bolt pattern (PCD): 6 × 130 Center Bore (CB): 84. Measuring Bearings. There are three important measurements to be considered before buying racing wheels. MiniExcavatorThumbs. Understanding Standard Size Dimensions. Measuring Wheel Diameter. Now the problem is the new bake line doesn't fit on the calliper side. These items can be cross merchandised in retail outlets and they are priced very competitively to be marketed as impulse type items. Wondering how to measure a toilet seat?… PlumbingSupply. 2 Measure the radius of the washer tub, in feet, and record this measurement. You now have the measurement for your length of pull on a rifle stock. Always consult the manufacturers instructions or engineering recommendations when making bolted connections. The final dimension is the Bolt Circle. I plan on sandwiching the 6x6 post with two 12X4x16 redwood beams. Metric Size Bolt Identification Example. Sort through a variety of strengths, sizes and hardness. For hubs with an even number of studs, simply measure across from the middle of one stud to the middle of its opposite. Some laptop manufacturers (ie HP & Compaq) measure overall length but some measure from underneath the head like you would a regular pan head. The first measurement that you will need to take is the overall length of the shaft of the bolt. Perfect for measuring overall and useable length for fasteners and more. The two motor feet measure 59 inches by 5 inches each. The bolt pattern of a wheel is defined by two numbers: the number of bolt holes and the diameter of the circle (in inches) that they form, measured through the centers of the bolt holes. Most bearing references now are laser stamped but these wear and rub off more quickly than the previous method, which was engraved deep in the bearing's metal. It does have a 10. Divisional Length. Ensure that your measurement(s) are from the center of one bolt hole to the center of the next bolt hole. Some have capacities of 3/16 in while others have greater capacities. 5″ diameter. You need to measure from the center of one lug to the center of the lug nearest to it. Getting the correct measurements is critical for purchasing pieces for a construction project or to replace attachments in a preexisting mechanism. Measure the inside edges for the I. To ensure your new toilet fit your space, you have to measure the rough-in size, which is the distance between bolts that hold the toilet to the floor and the wall behind the toilet. With rotational torque, the object is free to rotate. Number of Holes N Diameter of Bolt Circle. What size Dyna Bolts? Am splitting up the triple garage into a couple of extra rooms and was wondering what size dynabolts I should be using to fix the bottom of the wall frame to the concrete slab? and how many bolts should I be using?. The second part, which is 06012 tells you the size. SERRATED BOLTS WHEEL BOLT Length Shoulder Dia. How To Measure Wheel Bolts Written by Hitchweb Team Wednesday, January 16, 2013 — 2 Comments I am trying to pick a Wheel Bolt and Wheel Stud for my trailer hub, how do I choose the correct measurements?. Padlock Measurement Guide This short video shows how to correctly measure the various parts of a Padlocks body and shackle: The diagrams below are designed to make it as easy as possible for customers to find the right padlock to fulfill their needs. I don't know about you, but I really don't care if that bolt I'm trying to remove is a 3/16", 1/4" or a #12. 9/16 inch Diameter If your U-Bolts are worn out, broken, or you're piecing together your on-suspension system, then you should easily find any U-Bolt you need, right here! Disclaimer: Due to the many variables and options for every vehicle, measuring your u-bolt's to insure you're getting the right ones, is crucial. Metric bolts are sized according to diameter, distance or spacing (in millimeters) between threads and length. When you are on the verge of procuring a new toilet, use a straight edge or sight down the back of the toilet to estimate where the wall would be. A bolt size, then, consists of these six indicators. You may search for your product based on diameter by selecting a measurement on the Size dropdown. Here is Lightning Bolt’s Metric Bolt Thread Pitch Chart. Each of these toys are filled with complicated mechanical systems and many, many different sizes of fasteners. So that's what I ordered. The size of the NUT will tell you the thread size of the Stem. 8mm odd it's an M5. So, they offer a way to put inch-size wrenches to good use on bicycles. Wood Screws. 5" 14 Bolt - Rear Axle To determine the ring gear diameter you need to measure the outside diameter of the. Because of their size, the pythons. This is called the major diameter and will usually be the proper size of the bolt. Key dimensions to measure for the flange itself are nominal pipe size and flange diameter. Guide to Fastener Sizes. Metric Bolts. This means that the hub has 5 bolts spaced evenly on a 4. Each lug pattern is measured differently. Fasteners diameter is measured either as a size number or as a direct measurement. These drawings will guide you to measure your application correctly to ensure proper fit and performance each and every time. The first measurement that you will need to take is the overall length of the shaft of the bolt. How do you know how to choose the right screw for the job at hand? Find out now. A Short Guide To Metric Nuts and Bolts Answers to the most Frequently Asked Questions Standard and Fine Pitch Th reads How to identify nut and bolt strength grades How nut and bolt strength grades compare Maximum Tightening Torques Why specifi ed torque is sometimes lower than the maximum Spanner Sizes Versus Bolt / Nut thread size. per bolt estimates can be as low as 40 sq. To make things simpler, bolt sizes are broken down into the letter "M," followed by a number. " If you ever come across a Torx bit that's mislabeled or doesn't have a T-size on. You can measure the distance in either direction The two most common lug patterns are 4 on 4" and 5 on 4-1/2" hubs. BoltSize-It offers a full line of personalized measuring tools and templates that can be branded with your company information. Use the wrench that fits when you get the bolt in your hand. Excellent for sizing bolts, screws, nuts (USS, SAE and Metric) and twist drills. Match wheels to hubs by the number of bolts and bolt circle. The starter on the 164 tooth bellhousing is mounted about. Metric Size Bolt Identification Example. The use of any spacer much thicker than 1-2mm (0. Here is an example of a rim size:. HI, Frigidaire makes several over-the-range microwave models that are all installed in the same manner. Measuring Specific Types of Fasteners. How to Measure your Trailer's Wheel Bolt Circle Lug or Bolt Pattern In order to replace a hub on your trailer, you will need to know the bolt pattern or lug pattern. If you need to replace your hubs, it's important to measure the pattern in order to make sure you get the right size. Is it the 10 1/2" or the 11 7/16" size, I would like to order the TCI Street Fighter and then start removing the old, so when the new one gets there it is ready to go in. 500 inch further outwards as compared to the 157 tooth bellhousing. To measure 5 lug pattern wheels, hold the end of the ruler or tape measure to the center of one bolt. I don't know about you, but I really don't care if that bolt I'm trying to remove is a 3/16", 1/4" or a #12. Measure the diameter of the bolt. How to Measure a U-Bolt. What is the Diameter of the Bolt / Screw? Measure this using a vernier if possible - if you are using a ruler do your best to measure outside of the threads. " Metric bolts list measurements in millimeters. The bolt is used as the starting point for measuring the length of a given set of leaf springs. Measure exposed shank on the back side of the wheel. Standard hole sizes for bolts are made 1/16-in. The next step is to measure and cut parts for the outside walls. Follow the link to view our selection of U-bolts. How to measure front brake hose? From banjo bolt to other end where it connects to hardline? When I jack up front and brake line is stretched out how do I measure it and how much slack should it have? What size banjo bolt is on wedge type front calipersbon Chevy Dana 60?. Use our free bolt pattern guide to find your vehicle's bolt pattern before you shop for custom rims. The diameter of a bolt is the width of the grip. If you are traveling and checking your tongue weight each time, you can make it easier on yourself by purchasing a tongue weight scale. 98mm bolt will be referred to as a 4mm bolt. Fret Size – Width and Height With the calipers, measure the width of the fret at the point where it meets the fretboard, and measure the height of the fret. Successful entrepreneurs do their homework to understand target markets, identify a customer base and size up the competition. Learn how to measure wheel offset and backspacing and lug nut torque specs. Place a neck bolt through the neck plate and body. The best way I can tell you to get them off is to take the correct torx bit, hammer it into the bolt (the hammering makes sure it's in their really good), get a big breaker bar, and break it loose while holding the head of the ratchet / socket so it doesn't move out of place. Most bolts use the shank diameter, which is the distance from one side of the bolt to the other through the center, measured at the top of the bolt, just below the head. This bolt should be 1 radius from the hubs centerline (If you will be putting on 26" dia tires, the bolt should be 13" from the hubs centerline). Use the Mudge Fasteners bolt head size chart to determine the head size, and wrench or socket size required, for any hex bolt or lag screw you use. To make things simpler, bolt sizes are broken down into the letter "M," followed by a number. This will change with the application of an external load. The shank is the shaft-like part of the bolt or stud. Jeep Wrangler, Bolt Pattern Chart. Ultimate Handyman 1,497,053 views. Both nuts and washers are sized by the fastener they fit. Two measurements are taken when measuring the wheel size, the diameter and the width. if you are trying to identify an internal (female) thread these data charts will not contain sufficient information. 4mm 94mm 73. When threads are cut or rolled the outside diameter will be reduced a bit. Each of these toys are filled with complicated mechanical systems and many, many different sizes of fasteners. 5 or 6 on 135mm. With a nut the thread density must also match. Re: How to Measure Rims and Wheels Excellent charts. Rear End Housing Measuring Diagram *Example: Bare housing is 60" from hub face to hub face and the pinion is located 2" to the left of the housing centerline when viewed from rear of housing. 5 or 2mm wider on each side of the thread, so an M10 bolt normally has a 13 or 14mm head. These measurements are to identify the wheel bolt circle (or bolt pattern), the wheel width and the wheel offset (or rear spacing). To measure the diameter of screws and bolts, you measure the distance from the outer thread on one side to the outer thread on the other side. Measure across the flats or just try different size wrenches on it. Where and How to Measure. Use a tape measure or ruler and measure across the gasket from the 9:00 position to the 3:00 position. Bolt diameter can also be measured using thread diameter, shank diameter and root diameter. For a standard toilet, the rough-in measurement should be between 11 inches and 13 inches. Otherwise the measurements will be off. 6mm 144mm 4 Hole Chainrings 5 Hole Chainrings. Each bolt typically has a hexagon shaped head and a shank that fits into the hole. Excellent for sizing bolts, screws, nuts (USS, SAE and Metric) and twist drills. The best way I can tell you to get them off is to take the correct torx bit, hammer it into the bolt (the hammering makes sure it's in their really good), get a big breaker bar, and break it loose while holding the head of the ratchet / socket so it doesn't move out of place. Follow the instructions laid out in this guide on how to replace a toilet flange, and you’ll soon return to dry floors. Pan Head, truss head, and Hex Head screws are measured from under the head. Measuring fasteners is surprisingly simple. The diameter of a hex bolts, machine screws and socket head screws is the shank diameter, expressed in inches for US bolts and millimetres for metric bolts. On bicycle chainring this dimension is usually measured in millimeters. In the example, there are 12 threads per inch, so the measure reads as 12. 5mm and that is the bolt size. For instance, a UTS bolt labelled #3-48 is a gauge 3 bolts or screw with 48 threads per inch, and a 1/4-20 screw has a 1/4 inch diameter and 20. 5" clutch that was run on it. Up to 10cm (4”) of the overall height of our headboards will be set below the top of the mattress (the pillow board). Definitions of terms are located below the chart. It is important to have the right tools and know how to measure fasteners. Hex bolts are measured from under the head to the tip of the bolt. This is the preferred latch for use with levers on roses, where the rose is generally 50mm in diameter. For sizes of 1/4” or lower, a number is commonly. Eventually all of the target style receivers may be switched over to this new spacing, so make sure to measure your spacing before ordering a stock. Step 1: Measure Shank. The best thing to remember with bolt or lug circles to remember,even number of lugs,measure straight across, and the bolt circle or pattern is what it measures,center to center. The pattern is measured in inches or millimeters and is displayed as the number of lugs times the diameter of the circle. Not only did he decimate the World Record in the 100m and 200m, he made it look easy. Bolt diameter can also be measured using thread diameter, shank diameter and root diameter. The final dimension is the Bolt Circle. (due to individual printer setting variations) PDF Page should be set to 100% with no image scaling. trying to get a new bolt so i can replace the pulley, i just need to know what size the bolt is or the part # XXXXX i can replace it. Length will vary according to the type of material measured. Metric bolt dimensions? … please explain! Just want a simple answer so I can measure a bolt with a ruler and order the correct one! 🙂 Except the thread size doesn’t define the size. Plastic Bolt Gauge. 25mm: – Has a shank diameter of 6 millimeters. 05 to get the bolt pattern diameter.