PLEASE READ! Drum sander operation/information

As many of you have noticed, the drum sander has been missing sandpaper on and off for about a week or so. When I was up there during prior to this I was having to change it out 2-4 times a day due to tears or excessive burn marks.

This post is to explain proper usage, tips and tricks, and to address issues I’ve noticed many members having using the Powermatic 22-44.

This machine is intended to flatten material - sanding it is a byproduct of that goal

Control Panel

Indicators for ON/OFF, Belt speed (feed speed), measurement for current height, Feed Logic read out.

The toggle flip switch at the bottom right is to turn the machine on and off.

The push toggle on the top right is for spindle on/off.

The large red button is for emergency stop.

The rheostat on the bottom left is for feed speed.

The mm/in button will swap the read out for the height read out.

The ‘0.00’ button will set whatever the current height of the spindle as read by the read out to 0.000

Understanding feed speed & feed logic

Before we get into how to use the drum sander and its operation its important to know why feed speed and feed logic are crucial to your success with the machine.

Feed speed is how fast you the belt will turn anywhere from 0-12 feet/min.

For smaller items (in width) you can use a higher speed as the load on the spindle will be much lower. For instance, if you were sanding a 2" wide piece of hardwood or a 1" shim you could probably start anywhere from 8-11 ft/min.

For wider material you must use a slower feed rate. I was doing 19 inch walnut glue ups and felt comfortable around 5-6 ft/min. The width is the total width of material you are sending through the sander at once (don’t think 6 2" pieces equates to 2").

Finding the happy medium where feed speed is optimal means you won’t burn your piece and you will save a lot of time (faster passes = faster finished project)

Feed logic works in preserving the motor of the machine, saving our sand paper, and saving your material from burning or gouging. If the machine feels your successive pass is too deep (trying to take off too much material) the LED indicator will ramp up based on the amount of load and feed logic will try to turn on. It will then try to slow the feed rate down to something it thinks is acceptable and continue to pass.

If feed logic can’t fix the issue because its just too deep of a pass the machine will shut down. (recovery from a shut down will be explained later).

This is all related to FOUR things only (the keys to success): 1) Width of material 2) Feed rate 3) Depth of pass 4) Sandpaper grit

Pre-Operation Check List

  1. Unlock the cantilever cover to check that sandpaper is installed correctly (will cover this later)

  2. Close the cover and lock it

  3. Open the blast gate for the dust collector

  4. Turn on the dust collector (Large corner unit) This is a MUST

Operation

To start the machine from a full power off follow these steps:

  1. Flip the toggle switch (if the machine doesn’t turn on rotate the emergency stop to check if it has been pressed prior to your usage).

  2. Set the piece you want to sand on the belt prior to turning it on and adjust the height of the drum so that the feed rollers just kiss the top of your piece at its highest point. DO NOT CRANK IT DOWN SO IT IMMEDIATELY STARTS TO SAND Back your piece off and leave it on the infeed table. If your highest is in the middle of your material eye ball it to the best of your ability (better to err on the conservative side)

  3. Turn the bottom left dial to your desired feed speed (remember: slower for wider, faster for thinner). If the feed speed indicator is blinking 0.0 it means the dial must be reset fully (audible click) to 0.00 and then you can turn the dial again to start the belt.

  4. Turn on the spindle by pressing the green button

  5. Feed your piece through. This is where you will listen to hear if its sanding. If it’s not sanding, slowly crank the wheel so that it just kisses the piece.

  6. Once you find the top of your piece is getting sanded every so lightly press the 0.00 button This is how we will track our successive passes and sand optimally.

  7. Crank the wheel down so that the indicator says -.002 or -.004. Yes…that’s 2/1000th or 4/1000 of an inch.

  8. Watch the feed logic indicator and see how many steps you are getting.

  9. Lower the wheel so the indicator is -.002 to -.004 less than the last pass.
    Each pass after this will be determined by your width, feed logic indicator, experience, and so on.

Belt installation

This is crucial to having a flat piece (the entire point of this machine is to flatten material - a by product of sanding.

There are two retaining clips on both sides of the drum that hold the roll.

Start from the left hand side and insert roughly 1-1.25" of the roll into the clip and tightly wind it over the roll left to right. The sandpaper is tapered on both ends to allow for it to wrap properly.

There should be ZERO overlap over the sandpaper. Minimal distance between the coiling (sliver of the metal drum will be seen).

The two areas that need to be looked at during your installation are the far left and far right where the paper clips in. You want this tight as possible as any bowing or overlap will cause that portion of the sander to sand deeper and result in messing up your piece (if doing something that wide or along that area of the drum) and will bog the machine down.

If its completely tight and when you depress the paper along the clips and there’s no bounce or give then you did alright.

Cantilever fine adjustments

On the left hand side below the belt is this black knob. It adjusts the tilt of the cantilever arm. I’ve spent 2 hours TWICE in the past week adjusting this so that over a 19" span there is <= 0.002 difference from left to right.

In most cases this won’t need to be touched for a while. I’ve put a note on there with date last adjusted and by who (me) but I figure we can all do this every 2-3 months.

If it so happens to be needing adjustment turn the knob to lower or raise the cantilever.

Tips/Tricks/Suggestions

  • If you are doing multiple pieces that all need to be the same thickness do them all at once. Use the dial indicator to achieve best results

  • End grain cutting boards are generally pretty wide. You should NEVER be going more than -.006 at MOST per pass. I’d suggest several passes at less. Yes its a slow process, but you decided to do end grain…

  • You can successfully sand all the way down to fractions of an inch. I made 3/32" shims the other day for a project without fail and got consistent readings from a digital caliper front to back on 2’ long pieces.

  • Achieve your sanding goal by choosing the best grit. Want to remove more material quicker? Go with 80. Want a smoother finish with less sanding lines? Go with 150 or 180.

  • Use the 0.00 rest and dial indicator to help you gauge where you need to be at. Your 4/4 material that you just sent through the planer is reading .802 inches on a digital caliper and you want a true 3/4"? .802 - .75 = 0.052 inches. This is your rough target number to achieve if you started with one TRULY flat side.

  • Listen, listen, listen…then keep an eye on feed logic. The machine will let you know if you’re doing something stupid. You can hear it. Then you will see it burn or gouge your piece. When you figure out the sound and how much to take off per pass you will be more efficient and it will just hum along.

  • If you for some reason took too deep of a pass that causes feed logic to turn off the sander immediately press the 0.00 button. Crank the wheel up so you can remove your piece completely. Do the reset protocol and dial your wheel back down to +0.020 and start the operations steps again. This will save you time from having to find where your starting point was.

  • Especially on wider pieces try to put downward pressure on the material where its meeting the belt during the entire pass. I often do some forward pressure (not enough to change the feed speed but just on the brink so I know it wont get held up because the conveyor is too weak) and downward pressure. When the material is almost through go to the other side and help ‘pull’ it out (not forcefully). the goal is to NOT let it stop during the sanding process - this causes gouges

  • Every 20-30 PROPER passes take a gum block and clean the belt

FAQ

How much should I turn the wheel for each pass? Read the dial indicator and aim for .002 to .008 depending on material width.

How can I flatten my cutting board or any material Run passes on just ONE side until that side is completely flat. Do this by using a pencil to scribble across the entire face. When all of that pencil has been removed, scribble the entire face again and do a successive pass at the smallest possible amount to remove it all at once. This means that face is flat. Now turn the board over and run it using the same method on the other side.

What’s the widest thing I can flatten? 44" in theory, I’d say realistically 42 though. The 22-44 means Anything from 0 - 44 inches wide. That’s what the cantilever arm is for. Your material can hang off and then you run each side through.

Even though I didn’t turn the wheel after my last pass and I sent my material through I can still hear it sanding This is a normal thing. The dial indicator is not an end all be all. It’s a tool and a guide to help you but isn’t perfect (it’s pretty damn close when I do my caliper testing).

I’m tired of the space not having sand paper and/or tired of using burnt up sand paper Hopefully this won’t be the case if people follow this advice, but in the mean time do what I do…buy your own. On amazon it’s ~$40 for 3 rolls or go to Wood craft for $60. Take it off each time you are done. There’s a reason the space can’t keep up with going through 4 rolls a day…it ain’t cheap!

How many passes will a roll last me? If you are conservative it will last you a LONG time. If you are ramping up so that feed logic is triggering often it won’t last you nearly as long. I’ve done 100’s of passes on a single roll with it still looking new and that’s not an exaggeration

Will this speed up having to sand my project for finishing Remember, the main goal based on the grits provided by the space are to flatten material. Getting snipe off the planer? The jointer blades aren’t cutting perfectly flat for you? Have a slightly bowed project? This is what 80-100 grit will do. If you toss in 180…sure it may help you finish faster, but we have THREE random orbits that will take an already flat piece and sand them for finishing WAY faster.

I have streaks/sanding lines, how do I remove them? Once your piece is flat grab the random orbit and go at it from either the same grit or one lower and work your way up. On end grain you will find this takes a LONG time.

I have horizontal (parallel to the drum) dips/gouges in my material after using the drum sander Your pass wasn’t clean and without stoppage. Read above where I talk about making sure it doesn’t pause AT ALL. Put downward and forward pressure just enough to keep it moving. Don’t worry, another 0.025 will take that right out.

Why is this so damn long of a post If you’re like me you enjoy using the space. You also may hate it or get annoyed when machines aren’t functioning like the way they should be and it prevents you from working on your project. I just want us to get better at what we’re doing so we all benefit from it and we make better stuff as a result. I’m not on the committee, I’m just doing this to save all of us headaches.

How many bars should I aim for on the feed logic read out I believe 4 is the magic number after having used this thing for so long. I think 5-6 is ok occasionally if you want to be super aggressive. Yes, everyone including me will tick the feed logic and you’ll get a feel for it. You will have less desirable results on your material, so be patient and you will save time and a better end product with less frustration

Man…I’ve sent my board through this thing at least 15 times and it’s still not flat! Why? Are you following my suggestions on depth per pass? Lets say you are doing 0.004 per pass. In those 15 passes you’ve removed 0.06 inches. That’s the equivalent of less than 1/16" of an inch. This isn’t a fast process, but its the BEST tool we have for flattening besides the CNC.

Someone told me burn marks on end grain (cutting boards) are just a fact of life with this thing They are wrong.

Final Notes
Yes paper will wear out and break eventually, but this…

is COMPLETELY preventable.

There’s discussion about putting a restriction on the machine so that only users who’ve taken a specific class that includes instructions on it and after showing proficiency with it can use it. This will benefit us all in the end and keep the woodshop flowing better. I can’t imagine the number of cutting boards not able to move forward and the number of times I’ve seen someone trying to take a 0.020 instead of a 0.002 pass have racked up in the prior 3-4 weeks.

Hopefully you guys can benefit from this information and hope to see everyone make some cool stuff.

22 Likes

Well done!

This is great! Thanks for taking the time to document all this.

I linked to it from the drum sander line in the Tools section of the wiki.

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I have an addition (sadly, this is from personal experience).

If the board is twisted when it starts, then it will wobble going through the rollers. It will end up uniform thickness, but it won’t be planar. You will need to use a wedge and double-sided woodturners tape to shim it so the base is flat. Sand one side flat, then remove the wedge, flip it over and sand the other side.

3 Likes

Great post and super informative, thanks for taking the time to write it up! Might want to tweak this quote a little since elections haven’t happened yet because I can see this as being one of those “well I heard it on TALK things”. Does that make sense? I may not be wording it right

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Gotcha, editing it now

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Hi there,

I read this yesterday and thought it was very informative. I couldn’t, however, get the depth gauge to zero itself so it wasn’t clear how many fractions of an inch I was taking off with each partial rotation. Is this part of the sander broken or was I doing something wrong?

Do you mean that when you pressed the “zero out” button it did not set the digital setting to zero?

@pjolone1

I wasn’t clear, sorry.

It did set the reading to zero but raising and lowering the drum sander didn’t change the 0.000 to anything else.

So there’s an issue that might be causing this which lubrication will fix, if you crank it say 3/4 the way up and the lower it(to demonstrate this issue) you’ll notice the wheel gets very easy to turn and you assume it won’t go any lower but continue to turn it and then you’ll notice it drop significantly in a patteren as in you continue to turn and it drops suddenly gets stuck then drops, stuck, drops, etc etc ive significantly improved the issue from when it was but without access and a desire not to remove anything to gain access, but all that would have to be done is Remove the drum itself which is just 4 bolts and the cool thing is it is removable in such a way that it can be removed and replaced without any adjustments needed or re aligning. I can do so if given permission next visit but that’s up to y’all. Also the zeroing out feature and the depth gauge no longer work after the electronics were replaced like 6months+ Ago but 100% perfect instructions and walk through, can anybody print and preferably laminate this into a booklet to have in the wood shop near the machine