Logan FAQs

1.3.. Many Logan Lathes have the model number stamped on the nameplate attached to the front of the headstock. Other Logan Lathes have nameplates, but the model number wasn’t stamped on the nameplate. For those lathes, you can deduce the model number by knowing the features and dimensions of the lathe, and matching them to the model number table at:
http://www.lathe.com/models.htm

1.4. How can I find the serial number of this lathe?

1.4.. The serial number is stamped on the ways of the lathe, at the tailstock end, between the vee section and the flat section, in a spot that is not worn by lathe use. You can read it by looking straight down on the lathe.

1.5. How can I find out the age of this lathe?

1.5.. Find the serial number of the lathe as directed in question 1.4. Then look at the table of serial numbers on the web at:
http://www.lathe.com/ser-no.htm

1.6. Is this lathe worn? Worn out? How can I tell? What goes wrong with Logan lathes?

1.6.. There are a few things on Logan lathes that wear with use. They will wear even faster with neglect or abuse.

The most severe form of wear is bed wear. This happens even faster if the bed isn’t constantly lubricated with a good coat of “way lube”. Lathes with hardened beds typically have very little bed wear, but you can’t be sure. It is very hard to tell bed wear visibly.

One good way to test for bed wear is to set up the machine so the bed isn’t twisted as described in question 2.2, then take a test cut on a long bar. If the bar diameter remains constant throughout the length of the cut, the bed is not worn. Alternately, you can put a long, straight, precision bar in the lathe, put a dial test indicator on the carriage, and crank the dial test indicator across the precision bar, watching for deviation in reading.

If your lathe bed is worn, it will be very expensive to repair. Grinding shops can precision grind the bed, but it will cost between $350 and $750 for a good bed grinding job.

Another form of wear is bushing wear. This is evident by a grumbling sound from the gearbox. Worn bushings can be easily pressed out and replaced. New bushings are available from Logan or from a bearing dealer.

Another form of wear is wear in the tailstock ram. This could allow the ram to droop or wiggle during the cut. To repair this, you need to bore out the tailstock casting, insert a bronze or cast iron sleeve, and then bore it to precise diameter.

The headstock bearings could also be worn. On Logan lathes, these bearings are cartridge ball bearings. If you feel any roughness when you turn the spindle by hand, you need new bearings. If the spindle moves in and out, it could be that the bearings are good, but the spindle is insufficiently tightened or incorrectly assembled. You can get new cartridge bearings from Logan or from a bearing dealer.

Here’s a good article on how to check out a lathe:
http://www.mermac.com/advice.html

1.7. How much does this lathe weigh?

1.7.. The shipping weight of a Logan 14” cabinet lathe is approximately 1950 pounds.
The shipping weight of a Logan 12” lathe is approximately 1050 pounds.
The shipping weight of a Logan model 1920 11” floor lathe is approximately 615 pounds.
The shipping weight of a Logan model 1915 11” bench lathe is approximately 505 pounds.
The shipping weight of a Logan model 200 10” floor lathe is approximately 520 pounds.
The shipping weight of a Logan model 210 10” bench lathe is approximately 420 pounds.

1.8. What size motor should I put on this lathe?

1.8.. Logan supplied 3 HP 1725 RPM motors for 14” lathes.
Logan supplied 1 HP 1725 RPM motors for 12” lathes.
Logan supplied ¾ HP 1725 RPM motors for 11” lathes.
Logan supplied ½ HP 1725 RPM motors for 10” lathes.
You can use a larger motor, but the belts may not allow you to take advantage of it.

1.9. How can I move this lathe?

1.9.. Lathes are heavy. You can seriously hurt yourself moving heavy machinery. You can also damage the lathe if you drop it. To be safe, hire a professional rigger. If you’re going to move the lathe yourself, get proper equipment and get a few strong, healthy people to help you. It requires at least two healthy people to move a lathe.

The best way to move a lathe is to disassemble it, transport the parts, and then reassemble it in the final location. The more you disassemble, the lighter the parts. Decide for yourself when you have the lathe into small enough parts and stop disassembly at that point.

First, remove the tailstock by sliding it off the end of the bed. Next, remove the leadscrew support and crank the carriage off the tailstock end of the bed. Now remove the motor. The motor mounting assembly comes off next. Once the motor support assembly is removed, you can remove the headstock from the bed.

Next, you can remove the bed from the base. If the lathe has cast legs, support the bed well before unbolting the bed from the legs. Two average, healthy people can carry an 11” lathe bed. Two strong people can carry an 11” lathe with headstock in place.

Reassemble the lathe in the opposite sequence.

You will need to disconnect and reconnect power to the lathe when you move it. The power line contains enough potential to kill you. To be safe, hire a licensed electrician.

2. Machine Set-up and Repair:

2.1. How do I adjust the backgear rack? Does pushing the shifter rod “in” mean back gear drive or direct drive?

2.1.. http://lathe.com/ll-group-archive/logan_lathe_back_gears.html

2.2. How can I get the lathe to cut straight?

2.2.. The classic way to set up a lathe is to use a precision level capable of indicating a slope of 0.0005” in 12” and two matched parallels. Place the parallels on the flats of the lathe bed near the headstock, place the level on the parallels at right angles to the lathe bed, and adjust one headstock foot for level. Then place the parallels on the flats of the lathe bed near the tailstock and repeat, adjusting one tailstock foot for level. After doing this, the bed should be free from twist.

An easier way to do the same thing is to put the precision level securely on top of the lathe carriage, perpendicular to the lathe bed with the carriage near the headstock. Adjust one headstock foot for level. Then crank the carriage towards the tailstock and adjust one tailstock foot for level.

If the lathe feet are not adjustable, place the right size shims under the foot for level.

Another option for leveling is to use adjustable machine mounts. Logan Actuator sells a high quality mount, made by Royal, which will allow easy adjustment, and secures the Lathe to the floor without the need to drill holes in the floor, and/or add anchors.

Once you have the lathe level, it should cut straight. Check this by putting a 1” straight, constant diameter bar in the chuck or collet, putting a dial test indicator on the toolpost, and cranking the indicator across the bar. The needle should not move. If it slowly drifts from one end to the other, the lathe bed is still twisted. Adjust for no change. If the needle varies nonlinearly, then the bed is worn. This can’t be effectively corrected by leveling.

Here’s another effective way to adjust a lathe, courtest of Rollie’s dad:
http://www.john-wasser.com/NEMES/RDMLatheAlignment.html

Here’s a good article describing how to set up a lathe:
http://easyweb.easynet.co.uk/~chrish/tsetup.htm

2.3. How can I add collets to this lathe? Which collets fit this lathe?

2.3.. Logan 11” and larger lathes came with a 2¼ - 8, L-00, L-0, D1-3 or D1-4 spindle noses. Logan supplied collet adapters for this spindle that fit 475 (also known as 5C) collets. The 5C collet is a very common size and is available in round sizes up to 1 1/16” and also in square and hex sizes. Decent quality imported round 5C collets sell for under $7 each and even less in sets.

Logan 9” and 10” lathes came with a 1½ - 8 spindle nose. Logan originally supplied collet adapters for this spindle that fit AC-30 (3AT) draw-in collets and AC-50 (W&S #1) collets. These are more limiting and less available than 5C collets, but equally precise and convenient.

You may be able to find used collet adapters to fit a Logan lathe at used machinery dealers. You can also make your own collet adapter. There were quite a few articles published in Home Shop Machinist and Machinist’s Workshop describing how to make a collet closer. Most show how to make a precision adapter that fits into the spindle nose and accepts a draw-in collet. With a draw-in collet adapter, a 10” Logan is limited to collets with a ½” bore, such as the 3AT collet. Larger lathes can accept 5C collets.

One article from 2004 shows how to make a collet adapter that fits over the spindle nose. This is a much more advanced project. Over-the-nose collet adapters allow a 10” Logan lathe to accept 5C collets because they don’t use the critical room inside the spindle nose.

You can buy new draw-in collet adapters made by Royal or new over-the-nose collet adapters made by Bison or Sjogren from Logan Actuator or other dealers.

2.4. Is a Logan spindle nose the same as a South Bend nose?

2.4.. Each lathe manufacturer made their spindle nose slightly differently. The 2¼ - 8 Logan spindle nose is similar to the 2¼ - 8 South Bend spindle nose, but the outside diameter of the smooth section on the Logan is larger than on the South Bend. This means that you will have to take a final cut on a generic backplate or faceplate to get it to fit on a Logan. You can mount the backplate or faceplate on the spindle backwards to take this cut, if you’re careful. If you buy a backplate or faceplate from Logan, it will precisely mate with the Logan spindle without any adjustment.

2.5. How can I make a backplate for a chuck?

2.5.. You can learn about this simple process from one of these excellent articles:
http://www.lathes.co.uk/latheparts/page7.html
http://easyweb.easynet.co.uk/~chrish/t-chucks.htm

2.6. Where can I get replacement gears?

2.6.. There are many used machinery dealers that have used gears available.
You can also buy new gears directly from Logan Actuator.

2.7. How can I replace the vee belt without removing the spindle?

2.7.. If the vee belt on your lathe is worn out, you can replace it with a Fenner PowerTwist belt, available from many dealers. This belt is made of many identical belt links. You buy it in bulk and snap together the length that you need. In some cases, a Fenner PowerTwist belt will run smoother than a continuous vee belt.
http://www.fennerindustrial.com/products/powertwist_ind.html

2.8. What color paint did Logan use? How can I get something similar?

2.8.. The early Logan Lathes were painted a very dark Blue-Gray. Sometime in the early 1960s, the color was changed to a Medium Gray or Machinery Gray. It was a very common color for machine tools at the time. The Medium Gray is readily available from many sources still. The Blue-Gray is not. The closest I've found is from Grainger, a spray paint called Dem-Kote Blue Gray, their stock number is 5FX11. This is what Logan uses now for the Lathe parts.
In 1971, the lathe manufacturing operation was moved out of Chicago by Houdailleand the color was changed to a metallic green. Joe Schulte found a paint that matches his 1952-vintage Model 200 perfectly: Benjamin-Moore High Gloss Metal & Wood Enamel, Oil Base (Alkyd), Deep base C-133 3B, Color ID. 2119-30, Color Name. Baby Seal Black, Color Book 133. Any Benjamin-Moore dealer can mix this up for you. The smallest sizehecould get was a quart. The name makes the color sound black when it is really Blue-Gray. Many industrial or auto paint stores will match color if you bring them a sample. Some will even load a rattle-can for you. I had good luck with the local Sherwin Williams dealer and their “Industrial Enamel” paint. Bring along your tailstock and they can match the color, complete with age and dirt stains.

2.9. Why won’t this chuck hold parts exactly on center?

2.9.. No chuck or collet is perfect. Even a new three-jaw chuck is only good to 0.002” or so unless it is adjustable. If your chuck won’t hold parts that closely, something is wrong. Here’s a list of possibilities. Any of these could cause a good lathe to wobble.
It could be that the jaws of the chuck are worn. Letting parts spin in the jaws wears the chuck quickly.
It could also be that the scroll of the chuck is worn. The scroll is a flat spiral metal plate behind the jaws.
Another possibility is that the chuck is mounted on the backplate wrong or that there are dirt or chips between the chuck and the backplate. Take it apart, clean it carefully, oil it, and reassemble it. That may help.
Still another possibility is that there is dirt or chips between the backplate and the spindle. Unscrew the backplate from the spindle, clean the threads in the backplate and on the spindle, oil both, and try assembling it again. Screw it together gently. It should not be forced together or spun on fast with a snap.
It could be that the spindle is bent. Put a dial indicator on the spindle nose to check it.
It could be that the spindle bearings are bad or that the spindle is improperly installed. Good bearings will feel smooth and have no play. Logan spindles are precision machined to give the bearings a precise preload when the spindle is correctly assembled. Preloaded bearings have no play.

2.10. What can I do to fix a 3-jaw scroll chuck with worn jaws?

2.10.. If the scroll is worn, there’s nothing you can do without a CNC machine and a lot of time. If the scroll is worn and you fix the jaws, the chuck will be true at the diameter that you used for the repair, but nowhere else.
If you’re sure that the problem is just the jaws, then you can set up a toolpost grinder or boring bar and regrind or bore the jaws true. However, you must do this with the jaws pressing against something. One way to do this is with a piece of sheet metal having holes for each jaw. Another way to do this is to drill holes in each jaw for a pin or screw, and have these pins or screws tighten down on a piece of pipe. Tighten the chuck on the sheet metal or pipe and the jaws will be locked in the right place.
http://lathe.com/tips/chuck-jaw.htm

2.11. Where can I get new jaws or different jaws to fit my old Logan chuck?

2.11.. Before you buy used chuck jaws sight-unseen, you need to know that there are hundreds, if not thousands of different jaw sizes. It is nearly impossible to find replacement jaws for a particular chuck unless you go right to the chuck manufacturer. Logan chucks were made by Buck, now Buck Forkardt. Buck Forkardt is not set up to support home shop machinists. Their prices for replacement parts are astronomical. It would be less expensive to buy a new imported chuck than to buy new jaws.

Logan Actuator Co. sells new chucks, made by Bison. These are high quality chucks, made in Europe and are great investments for your Lathe.

2.12. What size pulley goes on the motor?

2.12.. The Logan 200, and in fact all Logan and Montgomery Wards Lathes, except the 9" and those with a variable speed drive, used a 2 step "V to Flat Drive".

For 10” lathes, the motor pulley (LP-1885 or LA-349) is approximately 2.31" & 4.28" in diameter.

For 11” lathes, the motor pulley (LP-1551 or LA1037) is approximately 2.5” & 5.25” in diameter.

You can buy these pulleys from Logan Actuator. Specify motor shaft size when ordering.

2.13. What is the right size chuck for this lathe?

2.13.. Logan supplied a 5” 3-jaw chuck and a 6” 4-jaw chuck for their 10” lathes. Logan supplied a 6” 3-jaw chuck and a 6” 4-jaw chuck for their 11” lathes. Larger chucks were available, but they are impractical on these lathes because the jaws would hit the bed when the chucks were opened. Larger chucks are also heavier, so they put a strain on the spindle and spindle bearings. In general, use the smallest possible quality chuck for the job.

2.14. What should I use for oiling the lathe? Oil level in reservoir?

2.14.. There are many places on your lathe that require frequent lubrication. Check your Logan manual for a listing of oil points. Logan manuals can be bought from Logan Actuator.

The ways (bed) of the lathe should be lubricated with a heavy, sticky oil called way lube. This is available in a few different viscosities (thicknesses). The right oil for Logan lathes is ISO VG-68 oil such as Mobil Vactra No. 2, Exxon Febis K68, Shell Tonna T68, Sun Way Lubricant 1180, Texaco Way Lubricant 68, Gulf Gulfway 68, or Chevron Vistac Oil 68X. These oils are available from most industrial suppliers like MSC and cost under $15 per gallon. Don’t substitute. Use true way lube and apply it with a clean cloth every time you use the lathe.

All other oil spots on the Logan Lathe can be oiled with ISO 22 grade spindle oil or SAE 10-weight non-detergent motor oil. Don’t use common “detergent” motor oil. You can get SAE 10-weight non-detergent motor oil from large automotive parts dealers for under $2 per quart. You can get ISO 22 grade spindle oil from industrial suppliers like MSC for under $10 per gallon.

2.15. What should I use to replace a flat leather drive belt?

2.15.. Logan Actuator supplies a synthetic belt that is the right size for your Logan lathe. The synthetic belt is stronger and stickier than the original leather belt, and requires no special care.

If you want to use leather, you can still buy leather belting materials from McMaster-Carr Supply.

2.16. Why is the drive on the Logan lathe from a vee-belt pulley to a flat pulley?

2.16.. This arrangement is called a “V to flat drive” and was very common on machine tools of this type. The primary reasoning was so that the belt could be shifted from one position to the other without having to release the tension, requiring another adjustment.

3. Machine and Parts Buying:

3.1. Which size Quick Change toolpost fits this lathe?

3.1.. For Logan 9”, 10” and 11” lathes, the “AXA” or “100” size quick-change toolposts from Aloris and Phase II fit well. For 12” lathes, the “BXA” or “200” size quick-change toolpost will be slightly more sturdy and still fit. The 14” lathes can also use the “BXA” toolpost or the “CXA” or “300” size.

Logan Actuator Co. sells Phase II Toolposts and will machine the T-Nut to fit your lathe at no extra cost upon request.

3.2. What is this used lathe worth?

3.2.. This is a very difficult question for many reasons:

3.2.. Different parts of the country (and world) have different demand, so different values;

3.2.. Lathes vary tremendously in condition, from broken, to worn out, to like-new, and everywhere in between; and

3.2.. Lathe accessories can be worth more than the basic lathe so value is strongly dependent on what comes with it (tooling, attachments, motor, etc.)

3.2.. To get some idea of lathe values, check eBay under sold items for similar lathes. Also check the classified advertisements in the Sunday newspaper for your region to see sales prices for similar lathes. With that information, your lathe is only worth what someone else will pay you for it.

3.3. How do Logans compare to South Bends or Atlas lathes?

3.3.. Logan lathes and South Bend lathes are comparable tools. South Bend had a larger line of lathes than Logan, so there are some models of South Bend lathes that have no parallel in the Logan line. But for lathes of the same weight and size, they are comparable. Atlas and Craftsman lathes were significantly lighter duty than Logan or South Bend lathes.

For an objective description of lathes of various manufactures, read:
http://www.lathes.co.uk

3.4. Does this steady rest fit a 10", 11" or which?

3.4.. Steady or Center Rests for Logan and Wards Lathes are unique to their respective swing size. In other words, one for a Logan 10” will not work on an 11”. Also, South Bend Steady Rests will not fit quite right.

One way to check is the height from the flat to the center line of the Steady. The heights are:

Logan 10” Lathe – 5-1/4”
Logan 11” Lathe – 5-9/16”
Logan 12” Lathe – 6-1/8”

Follow Rests are a bit trickier to figure out, but the Logan 10” and 11” use the same Follow Rest.

There have been several reports that a South Bend 9” Steady will fit a Logan 9”. Also, it appears that the Logan 10”/11” Follow Rest fits a South Bend Heavy 10.

3.5. Are parts from one Logan lathe interchangeable with those from a different model?

3.5.. Some parts are interchangeable, while others are not. Here’s a few common parts:

3.5..1. Generally speaking, the beds are interchangeable for 10" and 11" and 12” Logan Lathes.

3.5..2. Most Logan 10” and 11” gearboxes are interchangeable. For more information, see:
http://lathe.com/ll-group-archive/adapting_a_qc_gearbox.html

3.5.. In addition, many parts from one Logan Lathe will fit another, if they are the same basic size or swing. One very serious exception is between the Logan 200 Series and 800/1800 Series 10” Lathes. The 200 Series (and the Wards Lathes) used a different spindle, which is smaller on the OD than was used on the other Logan 10” Lathes. As a result, none of the parts on the spindle are interchangeable, including the Bull Gear, Pulley, Cone Pinion, Spindle Gear, etc.

3.6. Where can I get cheap parts?

3.6.. There are a large number of used machinery dealers that take apart machines and sell the parts. Many have a large collection of Logan parts.

When buying used machine parts, make triple-sure that the part they are selling is the part you need. Also, make sure that you know the condition of the part. “Looks good” could mean many things. Reputable dealers will sell you the part with a guarantee of return if defective. If they won’t give you a guarantee, find out why.

3.7. Where can I get good parts?

3.7.. There’s some risk when buying used parts. Logan Actuator is selling many new replacement parts for Logan lathes, including gears, belts, accessories, and manuals. Either look on the web store: http://store.lathe.com/ or contact Logan directly: mailto:sales@lathe.com

4. Machine Use:

4.1. How can I cut metric threads on a Logan lathe?

4.1.. Logan lathes came with gears for inch threads and an inch leadscrew. The stock Logan lathe can’t cut precisely accurate metric threads without replacing gears.

Some metric threads are close to inch threads. Slight inaccuracy can be accepted in some cases. In those cases, try the nearest inch thread. For example, if you need a metric pitch of 1.0 (1.0 thread per millimeter) you want 25.4 threads per inch. The Logan gearbox can cut 26 threads per inch. That may be accurate enough for a short bolt.

To cut precise metric threads, you need to have a 127 (or multiple of 127) tooth gear in the geartrain. Logan sells a 127 tooth gear for this purpose, but it is expensive. You can cut metric threads that are within 0.02% accuracy using more economical 37 and 47 tooth gears. These are also available from Logan and much more economical.

For detailed advice on setting the geartrain of a Logan lathe for cutting metric threads, see:
http://lathe.com/tips/met-thd.htm

4.2. How do I eliminate chatter when cutting?

4.2.. A tool that is cutting only at a small point will not chatter. A tool that is cutting over a large edge, such as a form tool, is more likely to chatter. Here are some ideas for reducing chatter:

4.2.. Reduce the amount contact between the tool and the work.

4.2.. Sharpen the tool.

4.2.. Increase tool back rake. Hard materials need 8 degrees of back rake. Free cutting steels cut with as much as 16 degrees of back rake. Use zero back rake for copper and copper alloys (brass and bronze).

4.2.. Use a very rigid tool holder.

4.2.. Use a tool holder that will flex with the tool moving away from the work rather than into the work.

4.2.. Sometimes, changing cutting speed helps for a few passes, but then the chatter returns. In these cases, use a different cutting speed for each pass.

4.3. How do I setup the tool?

4.3.. The cutting edge of the tool must be exactly on lathe center height. If the edge is slightly below center height, the tool can be dragged under the work, which can break the work, break the tool, or jam the lathe. If the edge is slightly above center height, the tool angles will be wrong and the tool will rub rather than cut.

For a lantern (rocker) style toolpost, tool height is adjusted by rocking the tool holder. For a turret toolpost, set tool height by adding shims (sometimes called “packing”) under the tool. For a quick-change toolpost, adjust toolheight by turning the stop nut on the tool holder.

4.4. Where can take classes on using a lathe?

4.4.. Locate vocational schools in your area. Some communities have adult education at night using the facilities of public schools. Another good place to learn is a local modeling club.

4.5. What books are good for teaching how to use a lathe?

4.5.. These are all good books for the beginner:

4.5.. South Bend: “How to Run A Lathe” (reprints available from Lindsay Books)

4.5.. Atlas: “Manual of Lathe Operation and Machinists Tables”

4.5.. LeBlond: “Running A Regal”

4.5.. These textbooks covers the lathe and other tools well:

4.5.. Moltrecht: “Machine Shop Practice, Vol.1”

4.5.. Kibbe, Neely, Meyer and White: Machine Tool Practices

Avoid books dating before WWII. Their advice is mostly outdated.

4.6. What should I use for cutting fluid?

4.6.. Cutting fluids keep the sharp tip of the tool cool, prolonging tool life. The sharper the tool, the less metal there is to dissipate heat from the cutting process. Liquid covering the tip conducts heat away from the tip effectively. Cutting fluids can also improve the quality of the cut.

Cast iron cuts well without any fluid at all. Alloys that contain lead, such as leaded steel and leaded brass also cut well dry. When cutting dry, keep cutting speed low to avoid overheating the tool.

Aluminum cuts well with kerosene, lamp oil, “A9”, or “WD-40” as a cutting fluid. Aluminum can grab or stick when cutting dry, so always use a fluid when cutting aluminum. If in doubt, read the cutting fluid container to see if it recommends use for Aluminum.

Lead-free brass can also grab when cutting dry. Find a cutting fluid recommended for brass.

Steel cuts well with many cutting oils. Monroe Cool Tool II is one of many good choices and is also good for aluminum and brass.

Water-soluble oils (flood coolant) work well in a production shop but are a lot of hassle for a home shop. They can grow mold and also rust tools, so cleanliness and cleanup are essential.

When cutting with carbide tools, either cut absolutely dry or cut with a flood coolant. If you use a small amount of oil or fluid on a carbide tool, then the tool will cool non-uniformly. This can cause the tool to fracture or chip.

There is no such thing as a perfectly safe cutting fluid. If possible, keep your hands clean when cutting. Wipe with a rag rather than your hand. Continued exposure to chemicals can lead to various skin problems and allergic reactions. Cutting can generate high temperatures, which can cause oils to burn. The smoke from oil can be hazardous to your lungs. If you sense oil fumes or any odor from the cutting process, get more ventilation in your shop.

4.7. How do I use the threading dial on a Logan or Wards lathe?

4.7.. For cutting an even thread such as 24 TPI, restart the cut with the dial set to any mark and it will restart the cut in the same place.

For cutting an odd thread such as 5 TPI, restart the cut with the dial set to any number.

For cutting a half thread such as 7-1/2 TPI, restart the cut with the dial set to to the same number every time. For example, if you made the first cut with the dial set to "2", you must make every succeeding cut with the dial set to "2".

For a quarter thread like 12-1/4 TPI or metric threads, you must leave the half nuts engaged and reverse the spindle at the end of each pass.

(Note, if cutting a thread divisible by 8 (8, 16, 24, 32, 40 TPI etc.) the threading dial is not needed at all. The half nut can be engaged at any point)

This document was prepared with an incredible amount of help by Robert Neidorff. Logan Actuator would like to express our deepest appreciation for his assistance.

Version 1.01 Last updated March 07, 2005

No part of this document may be reproduced in any manner without the express written consent of Logan Actuator Co.

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