Any questions? Start here (FAQs)

Can I upgrade to a 2 bearing quill?
This is by far the most frequently asked question. People assume “more bearings equals better”. This is not necessarily the case.

I am not a fan of the 2 bearing quill at all. Over the years, I have seen plenty of bent shafts on 2 bearing quills, always with a customer story about turning a blank or chunk of wood as the culprit. I can’t recall ever seeing a bent single bearing quill.

Yes, any Mark V can be upgraded. If you have a poly v drive, a 2 bearing quill can directly replace the single bearing quill. If you have a gilmer drive headstock, then you need to replace 3 other parts to allow for a 2 bearing quill. The drive sleeve needs to be converted from a gilmer configuration to a poly v one. The fixed sheave on the idler shaft has to be similarly changed out. And also the gilmer belt needs to be changed to a poly v belt. This typically adds $100 to the cost of your repairs using used parts. If your machine is 1985 or newer you have the 2 bearing quill.

Now, should you convert? SHORT ANSWER, NO!!! Mark V’s used single bearing quills from 1953 until 1985. Why did they switch, then? One of their competitors at the time went to a 2 bearing style, claiming it was better, and SS simply followed suit. It’s always been hype that 2 bearing is better.

You see, the back of the quill is supported by the drive sleeve (see photo below). Thus a single bearing quill is really a 3 bearing quill. Placing an extra bearing in the drive train merely adds more friction. If your bearings and components are all fine, I don’t believe you will see any difference between the single and the double bearing performance. In fact, in a 2 bearing quill, the inner bearing is the first to go in my experience. So I believe that there is no need to go to a 2 bearing quill.

Save some money.

The rear spindle of the quill is supported by the drive sleeve component thus all single quills are really 3 bearing quills.

The rear spindle of the quill is supported by the drive sleeve component thus all single quills are really 3 bearing quills.

Should I convert to the 1-1/8 hp motor?

If your headstock is newer than a mid1962, you have the larger motor. Or if you bought your machine used, check the motor because some owners did change out their motors over the years.

Unless your motor is fried, I typically tell people to keep using their existing motor, whether it is a 3/4 hp or 1-1/8 hp. The original Shopsmiths, the 10e and 10er, did and continue to do fine with only 1/2 hp motors. A headstock with a 3/4 hp motor should do anything you want it to on a Mark V. As long as your bearings in the motor are good, it should give you great service. Changing bearings in a motor is a lot cheaper than buying even a used motor.

I have also read than the standards for measuring motors changed about the time Shopsmith went to a 1-1/8 hp motor, and that the new 1-1/8 rating is the same as the old 3/4 hp rating, so they may in fact be identical in energy output.

The motor used in Mark V’s is unique. You can’t just take any old off the shelf motor and put it in a Mark V. The floating sheave system for speed control requires a much longer shaft than is typically found on motors. Thus you either need to buy a used one (which may need bearings itself) or a new one from SS. Either costs you much more than taking care of the one in your machine.

About the only user who could benefit from a 1-1/8 hp motor over the 3/4 is one who owns the SS Mark V mounted planer (not jointer, planer). The 3/4 hp is fine for drilling, boring, sanding, lathework, sawing, and all the other SPT’s and add-ons made.

I also believe the 3/4 hp motors are very well made, better than those from the 1980’s on certainly.

Should I convert to the Poly V drive system?

In many ways the Gilmer system is superior to the Poly V system so if your headstock has a gilmer drive, I would keep it that way.

The quill and drive sleeve contact securely metal to metal with the Gilmer ( with just a few exceptions). The quill and drive sleeve meet with a sacrificial plastic drive ring assembly with a Poly V drive.

The “tank treads” of the gilmer belt are less likely to slip, although most have a force-activated clutch in the drive sleeve to allow for slippage.

Gilmer belts don’t develop a distortion from years of storage and they don’t wear out as quickly as the poly v style. Poly v’s can become distorted easily from sitting and have to be replaced for that reason alone.

Poly v’s also require more tension to prevent accidental slippage and that is harder on the drive sleeve bearings and the idler shaft bearing.

To convert from gilmer to poly v requires changing your quill, drive sleeve and your fixed idler sheave along with the belt, adding to the expense of the conversion.

Poly v belt

Poly v belt

Gilmer belt

Gilmer belt

Mark VII, Mark 7, Mark II, 10e, 10er

You can certainly keep these other machines working with some work and ingenuity. The Mark VII has several parts which are no longer made. If any of these fail, you would need to get the parts from another machine, repair it yourself or have it machined by a local machine shop. The quill, drive sleeve, idler, control sheave and motor bearings are all standard bearings and are available from your local bearing supplier. You can make do with a Mark V poly v belt, and the drive belt is something you may be able to pick up locally. The electric switch would need to be modified and also the plastic cam in the speed control. The plastic rack the headstock moves on can be removed.

If all else fails, you can use a Mark V headstock on the Mark VII frame, you’ll just lose a couple of the functions (dust collection, reversible motor, shaper function).

There is no one currently specializing in Mark VII’s, but I wish someone would step forward to do so. I get a call every month looking for someone to fix a Mark VII.

For 10e/er service, contact Skip Campbell in Texas who is the leading expert on those machines.

What do you think of the new Mark 7 (electronically speed controlled) headstock

Not worth getting. These cost $1,800 or more just for the headstock. I don’t feel the electronically adjusted speeds help anyone other than woodturners. The speed range goes slower than the manually adjusted speed control of the traditional Mark V, which is an advantage to turning. But this does not help you drill, sand, saw or do any other the other functions better. For the same money, a wood turner can buy a very good dedicated lathe which will be of a proper height, a larger throw, and a longer bed. Also, the Mark 7 uses a password and you know how hard it is to remember passwords, and your family won’t be able to use the machine if you die and take the password with you. I also believe the combination of computer board and sawdust is a recipe for disaster. All of the early Mark 7 headstocks were rife with problems and it seems like they all had to go back to the factory. Maybe it is all straightened out now, but I wouldn’t spend that sort of money on this.

Is my motor fried?

Often, motor problems are caused by the bearings, belts, alignments and other problems in the headstock. Every bearing and both belts must be 100% so that things work right. To determine if your motor has a real problem, do the following.


Unplug and drop the motor from the headstock. Remove the drive belt from it so it doesn’t rub on the motor shaft at all.

See if you can rotate the motor by hand. Just because it can turn doesn’t mean the bearings inside it are okay. Listen for any scraping noises. The fan sheave can be rubbing or binding on the motor housing. If there is any noise like this, you’ll need to remove the sheave and investigate that first.

Now you can plug in again and try turning on the motor. If it kicks right on and works, you have problems inside your headstock.

If you hear humming but no turning you may have a bad capacitor. You can remove the capacitor and have it checked by an electric shop. (Note: some capacitors are internal to the motor). If the motor spins too slowly, bearings could be very bad and/or capacitor could be going out. If the breaker blows after a delay, it could be bearings.

If the breaker blows immediately, you probably have a short. This could be a short at the switch, in the pigtail leads, in the cord or plug, or it could be the windings inside the motor. You can see some of the windings in the motor from the air holes. If you see blackened wires, or if you smell a burnt smell, it is likely the windings. If it is the windings, you can have it rewired (expensive) or buy new/used. All other problems are cheaper and easier to fix.

One thought on “Any questions? Start here (FAQs)

  1. Jacob
    Thanks for the sound advice on repairing my Shopsmith Mark V the sheaves were sticking from the varnish build up just like you said in your video I used the proper penetrating oil cleaned them up and I’m up and running. I felt more comfortable cleaning up and evaluating my machine while I had it apart once again thanks to your tutorial videos. My father bought my machine back in the late fifties it’s been a great runner with minimal repairs. I plan on using your website for purchasing future parts for repairs I recently got stiffed on a so called tune up kit from Shopsmith I won’t make that mistake again.
    Thanks again


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