# Surface Drum Sander Build



## rdean (Mar 15, 2019)

I will be building a 10" wide surface sander mostly from pieces and materials in my shop.  I have checked several different machines and down loaded the owner manuals to get some ideas.  It will be open ended so you can sand 20" wide by turning the part around and running it through again.
I have a 3/4hp 1725 rpm motor that will be direct coupled to the drum.  This power unit will be raised and lowered by a hand crank and using linear bearings.  
I am making this as I go long so no drawings or sketches.

First the drum assembly
I have a piece of 3" 40 schedule steel pipe that I will use for the drum and two round steel disks.  The disks were something I picked up out of the trash many years back and thought I can use them for something someday.  The shaft is 30mm because I have the shaft and some bearings to fit.  What I have in the shop will determine how it ends up.  I will need to buy some materials and parts but I like to use what I have.



I bored the disks to fit the shaft and added a set screw in each.  I turned down the outside of the disks to just fit inside the drum and welded them in place.
Next to the lathe to true up the outside of the drum.



Drum completed and inside painted.



The bearing retainers were turned from some mystery steel chunks out of the scrap bin.



Here they are painted with the bearings fitted and the holes drilled and tapped.



And on the drum.



That's all for now.
Thanks for looking
Ray


----------



## Tom1948 (Mar 15, 2019)

Looks good Ray. I cant wait to come see it in person...... Tom


----------



## rdean (Mar 16, 2019)

I made the two end plates and 4 rails 3/4" steel round.







Thanks for looking
Ray


----------



## 7milesup (Mar 16, 2019)

I built a 26" wide drum sander about 30 years ago.  Still have it in my shop and still use it.  5hp main motor with a 1/4hp geared motor driving the conveyor belt.


----------



## brino (Mar 16, 2019)

This build is off to a great start......I'll am "watching" it.
Thanks for sharing it!
-brino


----------



## Ulma Doctor (Mar 17, 2019)

looking good!


----------



## rdean (Mar 17, 2019)

More progress

Made a bracket for the upper motor support, cleaned up and painted the motor.




The Love Joy coupling came in so I assembled the head assembly and ran it up.






Ran nicely but getting some noise from the Love Joy no matter how I adjusted the motor.    I think I will order a softer rubber coupling and see if that helps.  It's not terrible but I would like it quieter. 

Thanks for the comments all

Ray


----------



## Latinrascalrg1 (Mar 17, 2019)

Do you have any plans to adjust the drum height?


----------



## rdean (Mar 18, 2019)

Latinrascalrg1 I received a set of these to allow the main assembly to move up and down smoothly.  The height adjustment is taking shape in my head and will be a threaded rod of some sort but not nailed down yet.



This caused a engineering change to the motor mount plate as there was not enough room for the linear bearings.  One of the joys of designing on the go as to say.  I had to shorten the square mounting bracket and cut slots in the motor mount plate.  I now have two holes that won't be used.




Bearing blocks test fitted.




Thanks for looking

Ray


----------



## Latinrascalrg1 (Mar 18, 2019)

Ok after seeing how you have the linear bearings mounted i see the direction it is moving, Keep up the Nice work


----------



## rdean (Mar 19, 2019)

Feed pressure rollers next.
Some mystery steel and a piece of chain link fence rail.




I made two rollers by pressing in the slugs and then turning them down for the axles.  They turned out well and I was feeling perty good about them until I tried to locate them between the outer support rods and the drum.  There just wasn't enough room.

Engineering change number 2.
I moved the lower support rods inboard and slotted their old holes for the pressure rollers.







Problem solved.

Next the pressure roller spring mounts.

Thanks for looking 
Ray


----------



## rwm (Mar 19, 2019)

How in the world do you get that thin walled tubing straight and true. It seems like if you take off much material you might go right through!
Robert


----------



## rdean (Mar 20, 2019)

Robert you are right if you are trying to make the tube true along its entire length it would be hard to do.  In this case the tube doesn't have to be a consistent diameter or even perfectly round.  It just holds downward pressure on the work piece with spring pressure.  

I did get the spring holders made and installed yesterday.  On the motor end of the housing they had to be about 2" wide in order for the mounting bolts to clear the linear rail so I just made them all the same size.  I don't know how much pressure is needed so I just installed some springs I already had to see how it works out.







Thanks 
Ray


----------



## rwm (Mar 20, 2019)

I see your point. I guess just the sanding drum needs to be true. This thing is looking great. Is your plan to use it on wood? Could it be used on aluminum to achieve a brushed finish?
Robert


----------



## brino (Mar 20, 2019)

Two more questions:
Where can we submit our orders and what's the lead-time?


-brino


----------



## rdean (Mar 20, 2019)

I have been planning to use it on wood but...




brino said:


> Two more questions:
> Where can we submit our orders and what's the lead-time?



I have to make one first and  another engineering mistake today. 
I now have four holes I won't be using. 

I cut the linear rails to the required length today and had a surprise.  The rails were hardened all the way through.  For the low price I paid I expected them to be only surface hardened so I had to get out the chop saw.







More tomorrow maybe.

Ray


----------



## rdean (Mar 21, 2019)

About 10 years back I was working on a project that didn't work out and when I went looking for something to make the base out of I ran across it again.  It looks like it will work fine so I cleaned and painted it up.







I made the upper and lower rail brackets and installed the unit on the base.







That's all for today

Ray


----------



## rdean (Mar 23, 2019)

The triangular shaped supports are bolted directly to the frame for rigidity. They are used to accurately adjust the sanding drum horizontally to the conveyor.  The adjusting bolt in the center of the rail is locked in place after the adjustment.







The drum height adjustment is by a 1/2" X 20 threaded shaft which results in a 0.050 per revolution movement. 
This showes how I cut the threads on the lathe.




When I motorized my home made winch last month I had this six spoked handle left over so I will see how it works here.  The maximum thickness of the sanded piece of wood will be somewhere around 4".




The project is getting close to making the conveyor system and the conveyor belt is something I have been thinking about.  I have some treadmill conveyor belt material that may work but how to do I attach the ends together?

Please reply if you have any ideas on the belt.

Thanks for looking
Ray


----------



## f350ca (Mar 23, 2019)

Great progress Ray. I'd sure like to have a drum sander. I seam to work in fractions in the cabinet shop, a 16 tpi jack screw would be easier for me to deal with.

Greg


----------



## 7milesup (Mar 23, 2019)

If you plan on wrapping that drum with sandpaper, you will need x-weight sandpaper which will stretch.  Maybe your sander is short enough that it will not be an issue, but on mine that I designed I ended up designing and fabricating a take-up mechanism on the right side of the drum.  If you don't do that, the sand paper will eventually bunch up and self destruct.


----------



## Latinrascalrg1 (Mar 23, 2019)

Treadmill belt would be one of the best choices IMHO.  As for how to connect the ends ???  There has to be some type of adhesive that would work on that material but in the end if all else fails I would think Sewing the ends together with some heavy Carpet/ Upholstery Nylon thread probably would work.  If this were my project My next question would be, "should i cut the ends and connect them together at a angle or 90° square ends?"


----------



## 7milesup (Mar 23, 2019)

Angle cut ends.  Also, if you use sewing as the method, you will get a "bump" every time it passes by your work.   You WILL see that on your work.  I would recommend using a thin fiberglass tape.  3M super 90 would probably work to hold it and still be flexible.  The other thing I would do instead of treadmill belting is use an abrasive belt as your conveyor system belt.  You will be much less frustrated in the long run.

Like I said before, I built my sander about 30 years ago and learned a lot about effective design parameters.  My sander is 25" wide or so and weighs at least 700 lbs.


----------



## Latinrascalrg1 (Mar 23, 2019)

Oh i like the sanding belt in place of the treadmill idea.  I dont think i would have ever thought of that and its the perfect option.


----------



## rdean (Mar 23, 2019)

Greg before I got into metal machining an error of 1/32" was good enough but now I'm chasing a few thousands and some times tenths.

Some of the factory made machines use an abrasive belt and that is probally the way I will go too.

7miles up 
Can you explain or have a picture of your system to hold the sandpaper?
I am thinking about a hook and loop system.

Ray


----------



## 7milesup (Mar 23, 2019)

I can post a couple of pictures later on this evening.  We are unexpectedly showing our house today (not even on the market) so I'm running around here like a lunatic getting it ready.


----------



## Latinrascalrg1 (Mar 23, 2019)

7miles, Id really like to see those pictures of your drum sander.

I have a few Questions for you also if you wouldn't mind..... Did you use one single sanding belt for the bed?  Do you think using the treadmill material as a supporting underlayer would be beneficial or is the belt more then strong enough to handle the job In Your Opinion?   
Thanks in advance.


----------



## 7milesup (Mar 23, 2019)

Ok.  Here we go.  Attached you will find some pictures.
The take-up mechanism is an arc shaped device that utilizes a spring and finger to pull on the sandpaper.  The spring pulls on the finger which then pinches the sandpaper along with providing tension on the sandpaper via an arc'd slot.  Not sure if that makes sense.  Basically one spring does two jobs of gripping the sandpaper and providing tension on the sandpaper.
The belt on my sander is an actual woodworking conveyor belt that I had fabricated for me. I would not go the same route again because after years of use, the "grippiness" is much less than it used to be because of dirt and the rubber aging.  I have even raised the bed and "sanded" the belt which helps for a while by exposing new rubber to grip the wood.  The sanding belt would be significantly better.  I had my belt fabricated for me years ago and it was expensive, at least for me at the time.
I would use just the sanding belt as the conveyor with nothing as an additional backer.  

You will find that the amount of wood you can remove at once in somewhat limited.  When I originally planned mine out, I had the intent of doing "abrasive" planing with 24 or 36 grit sandpaper, since I did not have a planer at the time.  I learned that that was not really a viable long term solution.  I also wanted use 220 or 320 grit but at least for my applications, any variations in wood thickness would result in immediate burning of the wood followed by the sanding strip destroying itself and then the 90 durometer sanding drum coming into direct contact with the wood before I could shut it off.  Man, that would fill the shop up with smoke real quick!  It had the smell of a campfire and a dragstrip rolled into one.
Also, keep in mind that I have a 5hp main motor with a 1/4 horse geared motor driving the conveyor.
You will also note that simple duct tape will hold the abrasive to the drum because if you wrap it correctly, it self tightens and unless you sand right next to the tape, it will hold.  As you can see in my pictures, I only have part of my drum covered.  Don't remember exactly why I did that but probably had a remainder of a roll I wanted to use.


----------



## rdean (Mar 24, 2019)

I should explain that I know nothing about large belt sanders or how they are should be made, I haven't even seen one close up.  So throwing all caution to the wind I glued some hook and loop material to the drum.  I used contact cement and trimmed with a razor blade.  It was only 6" wide so you can see the seam in the middle.




I turned the sander on and nothing flew off or came loose so on to the next step.  I had a piece of 6" wide piece of sand paper with a hook and loop backing that I wound around the drum and trimmed to fit.  You can see I didn't do a very good job as it is about 1/4" too short.  I fully expected the sand paper to become airborne as soon as the switch was flipped but it didn't it just stayed in place.







So will the sand paper stay on during sanding operations?

I made a make shift table by clamping a piece of pine board to the frame and found a piece of scrap poplar about 2" thick for a test piece.
I ran this through several times and eventually took of about 1/16" off to clean it up.  It turned out almost perfect and was within 0.015 thickness on  all four corners.





This absolutely not the way I will wrapping the drum but it really encouraged me to continue.

Thanks for looking

Ray


----------



## rdean (Mar 27, 2019)

I went to the flee market over the weekend and got this 54" wide sanding belt.




I will try to make a conveyor belt out of it, we will see how that goes later.
The time has come for the sander to get it's own legs.  It was getting too heavy and large to move around on the bench so I made a stand for it.




The conveyor is next.

Thanks for looking 
Ray


----------



## rdean (Apr 1, 2019)

Had some time this weekend to work on the conveyor.
I made some bearing blocks for the drive end and a couple of adjustable blocks for the inlet end.
2" angle iron for the conveyor base and a piece of steel panel I had cut out of an electrical cabinet for the monitor to fit into.
The rollers are from an old tread mill that I cut down to length. The drive end roller was made by pressing in a steel slug and turning the slug down to fit the bearings.
I was able to cut off a 10" wide piece of the sanding belt I got last weekend.  I then cut the belt at a 45 and just taped the belt together to get a feel of how it would run.  
I have watched many videos of different ways to splice a sanding belt and I am still not sure witch method is best.  
Does anyone have a suggestion how to "but" splice a conveyor belt?













Thanks for looking

Ray


----------



## Janderso (Apr 1, 2019)

Making good progress!!
I am enjoying the ride.
You are a very capable and intelligent Hobby machinist!


----------



## rdean (Apr 1, 2019)

Thank you Janderso for the kind words.  I make many mistakes but I am usually able to cover them up or turn them into new features. 
If you don't know what will or won't  work then you are truly open to new successes. 

Ray


----------



## Latinrascalrg1 (Apr 1, 2019)

rdean said:


> I make many mistakes but I am usually able to cover them up or turn them into new features.


In my neck of the woods there is no such thing in a shop as a "Mistake!"  We call them Creative Challenges or design improvements.


----------



## rdean (Apr 1, 2019)

Bought a roll of this tape today.  It has fiberglass fibers along the width and the length of the tape.
Just a quick and dirty trial on a piece of 2" wide sand cloth and I was impressed.  I could not pull it apart but tomorrow will be the ultimate test on the conveyor belt.




Ray


----------



## rdean (Apr 3, 2019)

I removed the old tape I had put on the conveyor belt and cleaned up the bottom side where the tape was.  On the top of the belt I used my hand sander to remove as much of the grit that I could get off in a 2" wide swath.  I installed the new Scotch tape on the top and bottom of the belt, installed and tentioned the belt.  
We will see if it holds up or gives up.






I made the mounting bracket for the conveyor drive and a dummy alignment sleeve to locate it properly.  I have a flexible coupling on order and it should be here soon.




For the control box I cut down a metal box I got at a garage sale over 2 years ago.  I installed the speed control assembly for the conveyor in the box.




Thanks for looking

Ray


----------



## rwm (Apr 3, 2019)

How do you control the conveyor belt tracking?
Robert


----------



## rdean (Apr 3, 2019)

Robert I was concerned that tracking might be a problem so I made the conveyor driven roller adjustable.  Each end of the roller can be adjusted independently or skewed to correct any tracking issues.  I found that after running the conveyor about a half hour the belt tracked just fine with no sideways motion. 
 Now to make a proper sanding belt for the drum.

Ray


----------



## rdean (Apr 4, 2019)

The coupling came in for the conveyor drive.  I had to bore it to size and install it.  The shafts even lined up with no wobble.




Bought a couple of switches one for the conveyor and one for the main motor.  Installed in the electrical box and finished up the wiring.




I had some 2 1/2" wide sandpaper 100 grit and glued the hook and loop material on the back.




After a few cut adjustments with the sizzors I wound the sandpaper on to the drum. 
Now for the first real test I found a scrap piece of poplar that I had used to check the temperature of my branding iron.  As you can see there were deep burn marks and an uneven surface.




This is how it turned out after taking about 0.100 off.




I expected there would be a few things to work out from the beginning but there weren't any.  The only thing I adjusted was the conveyor speed as I had it too fast.  The board was sanded to within 0.010 thickness all around with a very smooth surface no scratches or lines.  The conveyor tracked perfectly and the belt never slipped.  The wood didn't slip on the belt and the press rollers worked fine also. The sanding belt stayed smooth and tight on the drum with no indication of coming off.

Everything just worked like it should but oh what a mess, saw dust all over the shop.  I guess I got really lucky.
Next will be some covers and a vacuum port for the dust.

Thanks for looking
Ray


----------



## rwm (Apr 4, 2019)

Awesome work! 
Robert


----------



## brino (Apr 4, 2019)

rdean said:


> I guess I got really lucky.



Nope, not lucky.
From where I sit it looks like the outcome of planning and skill on the part of the builder.



rdean said:


> Next will be some covers and a vacuum port for the dust.



Great progress keep it coming!

-brino


----------



## rdean (Apr 5, 2019)

Getting close to the end of the build.
Fabricated a hinged cover for the drum area, made 2 brass hold down thumb screws, and installed the vacuum port.   







Big problem, the 6 spoke hand wheel I had installed won't work because I can't open the lid.  
So off with the old and make a new elevation handle with one spoke.




Polished up the aluminum covers some and here it is ready for work.




There will probably be some issues as time goes on and I may have to redesign parts of the sander but overall I am happy with the way it turned out.  
I will be getting some sandpaper in different grits that has the hook and loop already installed as I can see a problem starting with the glue not holding the hook and loop to the sandpaper.

Thank each and everyone of you for the kind words and sticking with me during the build.
Thanks for looking
Ray  

Now what to make next?


----------



## rwm (Apr 5, 2019)

Run some aluminum through it!!!
Project of the month.
Robert


----------



## eugene13 (Apr 6, 2019)

great project, great presentation


----------



## rdean (Apr 7, 2019)

Robert I hear you and I gave it a try today.
I had a old abused piece of aluminum that I got from somewhere and have been cutting pieces off of.  Normally I would have ran this on the mill with a surface miller to clean it up first.  The surface is really in poor shape and some places are eaten away and others stick up over 0.100 but I thought what the heck I will give it a try.




This is as far as I got before the sandpaper was used up but I was impressed what it actually did.  I used 100 grit paper and  had to stop several times to cool the aluminum so I could hold it.  If I would have used a coarser grit first and then the 100 grit it probably would have worked better.





It did leave a nice brushed look but maybe should have been coarser.

Thanks for looking

Ray


----------



## magu (Sep 4, 2019)

Great project Ray! 

I'm definitely putting this on the "get to" list. I would love to have a drum sander for my woodworking, but the price is hard to justify.


----------

