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Just got his bad boy up and running today and want to first thank Pat Hawley and Matthias for the design and plans. It was the first time I really built something according to any sort of plans. I always want to change something but I built this according to the plans, metric as well, and all went pretty well. Plans here http://woodgears.ca/sander/thickness.html

19" long drum

1 HP Craftsman Band Saw Motor

1" T G & P steel shaft - Turned, Ground and Polished. https://www.speedymetals.com/pc-1623-82 ... 0-001.aspx

1" Pillow Blocks - http://www.amazon.com/Bearing-UCP205-16 ... low+blocks

Split Tapered Sheave and Bushing - http://www.surpluscenter.com/sort.asp?c ... E%20PULLEY
http://www.surpluscenter.com/sort.asp?c ... 0h-bushing

Super Grit Sandpaper - https://www.supergrit.com/products/prod ... eve-hl.asp I got 8 ft. of the hook which was just about right for the 19" long drum - had a little less than a foot left over. I also got 6 ft. of 80 and 6 ft. of 120 grit but really don't what length each piece needs to be to order again. I'll measure then and see how long each piece needs to be.

I've only done a couple of test boards and it sands really well and the dust collection is great. I have a switch that operates the drum sander and an attached receptacle that powers the Shop Vac at the same time. I also put it in on casters so I can wheel it outside the garage very easily. I had an old box that rests on the bottom rail for sandpaper etc.

As you can see the motor is not your standard bottom mount so I had to build a metal frame to house the 1 HP band saw motor. I really like having 1 HP even though I've read some users have 1/2 HP. I'm not sure how you can have too much HP and the 1 HP is nice.

The biggest hurdle was the motor's 14 mm output shaft and with some help form another board member I was able to locate the proper sheave and bushing. Once that was solved it was really quite easy to put together, again credit going to the design and plans.

The part I found most difficult was truing the drum. It was easy to get it flat but to get the diameter the same from end to end took some tweaking of the support frames to get it right. I also started out with some laminate flooring for the feed bed but the seams didn't lay completely flat so I removed that (fun) and put a melamine-type finish on the feed bed.

Oh and here's something not to try. Don't try and sand right up the edge of the drum if all you have is the hook and loop holding the paper in place. Depending on which way your drum rotates one end of the drum WILL have the end of the sandpaper ready to be grabbed by the materials and it WILL tear off all the sandpaper and send the dust cover flying and cause a whole lot of angst. I'm considering a hold down at the vulnerable end to keep that from happening and being able to use the entire drum.

I wonder what others have done as I haven't heard of the happening before.

Here's some pics. If you have any questions please ask and thanks again for all the help on this.

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Nice job Larry. The main shaft you have in your drum looks way more robust than the tube is used for mine. I wonder if yours will always stay true. I seem to have t re-true mine every couple of years though I don't understand why.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

I really wanted it to be stout and last for a long time and as you might have seen it's a 1" shaft, turned, ground and polished which I learned about from the other thread on your sander design. I bought a 36" long shaft and have yet to cut off the extra 10".

When you say you have to true it Pat does the drum get out of round? Hard to imagine...Or does it get non-concentric on the shaft/pillow blocks? Trying to imagine how it can change with the Hook and Loop and sandpaper on it.

I'll try thicknessing a plate sometime today for its maiden voyage. Thanks again for the design.

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With mine, it seems that after a while I can feel the wood "pulse" as I push it through the sander. It gets worse as time goes on and, unless I push the wood through very slow, I can start to see waves on the surface of the wood. Also I can start to see uneven wear on the sand paper. So then I have to take off the Velcro and true it up. PITA but I don't have to do it very often. Actually, now that I've bought the Ryobi, I probably won't ever have to do it again.

You might be able to find some use for the extra shaft still on your drum sander. I've seen several guys that have attached a big disk and a little table to make themselves a large disk sander.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Are you able to adjust the height of the drum?

Great job, Larry!

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Always have plenty of sandpaper; it's rough out there!

So the drum gets out of round through the sandpaper??? Then you have to sand the MDF drum it round again?? Hard to imagine that happening. I can understand the velcro and sandpaper 'bunching up' a bit with usage and causing a 'pulsing' but that would only require repositioning the sandpaper. That's weird Pat, and I'll keep an eye open for any thing like that.

GREAT idea for the extra shaft. I wonder if I could buff with that thing?

Curious - what Ryobi did you buy?

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There are a couple ways to adjust the height of the drum. You can shim up, or trim down the 2 x 4, under each pillow block. You can also raise/lower the front and/or back 2 x 4's that hold the bed in place which of course doesn't adjust the height of the drum, but the bed underneath it. I did everything listed. It was pretty tricky to get the bed level and true with the support 2 x 4's then get the heights correct so the drum is the same diameter from one end to the other. Never did get it perfect but it's within a light 1/16". Again, trickier than I expected.

The plans in this case were followed exactly and all the heights came out really good but it is after all 2 x 4's and wood screws and tolerances of 1/16" - 1/8" are common. Combine that with an uneven concrete floor and there's a couple more variables.

If building again I would leave a few screws out and check everything for position and clearances before permanently screwing in place.

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Pat, did you use a clamp of sorts for the end of your sandpaper to hold it in place? Or just the hook and loop all the way to that narrow little end? I tried to sand up to the end of the drum and the small sandpaper wedge that ends up on the end got caught by the material and it ripped the whole piece of sand paper off with dust cover flying. etc. I'd like ti use the whole drum so I might fashion a clip/clamp to hold that small end in place.

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Larry: I built a sander about 10 years ago and did not use any glue or hook and loop. I went with hose clamps on either end. Also you can make your table so that it rises or lowers on one end at the piano hinge location. Makes adjustment much easier.
Tom

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A person who has never made a mistake has never made anything!!!

I don't quite get that, Tom ...

Why would adjustment at the hinged end be an advantage ? You already have a very precise adjustment at the infeed end , why would you need anything more ?

I'm thinking he's talking about adjusting the bed level to the drum, not just up and down. Getting the bed level to the drum is the tricky part in fine tuning this design.

It's great idea. Did you build that adjustment in Tom? I'm thinking of designs right now but would love to see/read what you did.

Hadn't thought of hose clamps either because the H & L seems so easy to change paper but hose clamps are not much more difficult it would seem. Gotta clear the hose clamp screws of course with your bed.

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I bought a used 16/32 Ryobi. I don't think they make it any more.

With the hook and loop once in a while I would catch the paper and it would come off and, true enough, this would happen more often near the ends. But it wasn't that often and no big deal. In fact, so far I am having more troubles with the clamping system on the Ryobi and I am tempted to convert it to hook and loop. As it stands, I have to use double sided tape to hold the paper on one end.

Hook and loop also has the advantage that you don't have to cover the whole drum so can use relatively small amounts of sand paper for doing narrower objects or even have two grits of sand paper on the drum at the same time.

It's interesting to me that people are finding the alignment of the drum with the table tricky. I didn't find that at all but I don't recall doing anything special...

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Larry: You have it right being an adjustment to make the table line up with the drum. It gets it very close and then you can run a abrasive clad plate under the bare drum to get it spot on.Works very nicely on mine. It's vey simple. I will try to get a picture to put up but it may take a week or so.

Tom

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A person who has never made a mistake has never made anything!!!

Do you have a power feed or do you hand feed the stock through the sander?

Hand feed. A little awkward with switching sides of the sander but no big deal.

I tried it last night on some walnut plates. Very slow to take off material and at first quite uneven in its final thicknessing.

What I think occurs with the hook and loop system is that the drum is actually softened by the H&L and if your stock is uneven to begin with that 'give' that the drum has will absorb that uneven material and sand of a similar amount across the entire plate. Meaning if you have one edge that's .140 and another that's .125 with a quick run through the sander there will still be close to that .015 difference in thickness.

What I found was that a VERY slow feed will tend to allow the drum to work more evenly across the plate taking down that .015 higher area and evening the plate out.

I'm just learning the tool so there's a bit more to discover but like most people know it is a 'sander' not a planer and it takes off very little material in a single pass so I'll probably plane to get much closer to final thickness then put the material through the sander.

The finish with 80 grit was very even and the machine overall worked very very well. I'll cut a 120 grit piece today and check the final sanding.

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That's essentially what I did by adjusting the bed height 'manually' if you will. And the 'adjustment' I'm talking about is not getting the drum 'flat' or parallel with the bed. That is very easy with an "abrasive clad plate." What I'm talking about is getting the drum to be the same diameter from one end to the other.

In order to do that everything has to line up perfectly and even though that might be possible with 2 x 4's and wood screws, it's not very likely. I also don't think it's critical, but something I wanted to see to add to the precision. Like I said I got to a light 1/16" and called it quits.

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Ahhh, that's the difference. I didn't worry at all about getting the drum the same diameter from end to end. I couldn't even tell you how close (or far away) I am. All I cared about was that it was true to the table.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

The easiest way to accomplish that is to design an adjustment mechanism, but for a machine that has already been built, shimming either one side of the bed or the drum should work well.
For this design, shimming at the drum seems like the least headache; simply place shim of desired thickness under the pillow block on the side thats "cutting low".

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Always have plenty of sandpaper; it's rough out there!

Like I said I don't think it matters much but I like the fact it's even across the drum. I suppose if it's too far off the speed of the larger diameter would be greater than the smaller diameter but important or factor in getting a good finish? Probably not so much.

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Has anyone used 40 or 60 grit with this design? I'm wondering how it will behave with such a coarse grit.

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If using H&L, I would not go coarser than 80 grit.
Coarser abrasives take a deeper cut. In my experience, anything coarser than 80 grit encounters enough resistance that the hook and loop begins to let go.

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Always have plenty of sandpaper; it's rough out there!

Ahh, exactly what I was thinking might happen. Thanks for the heads up.

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Although H&L has been around for some time, lots of folks still don't understand how to make the system perform to maximum potential.
H&L offers convenient attachment, but if used properly, it will generate less heat buildup. This translates into less burning of the material (wood), less loading up of the abrasive, and significantly longer life of the abrasive.

The important thing to remember is that with our chosen material (wood), excessive pressure is usually considered the enemy when sanding. Far better results if we simply let the abrasive do the cutting.
We have two modes of operation from which to choose when using these machines- abrasive planer, or drum sander.

When people want to significantly alter dimensions or shape of the material, they're asking the machine to be an abrasive planer.
For best results, this requires a hard backing, coarse-grit abrasive, and a very stiff bed. The material is forced ("pinched") between the abrasive and bed, creating the pressure that's needed for shaping/thicknessing.
This is a grinding operation, and the best type of abrasive roll to use for this is simple cloth/paper-backed roll that is retained by end clips (or other similar retention mechanism). Grinding creates heat, and both PSA and H&L do not fare well when the heat is on.
The "loop" portion of H&L is affixed to the drum exactly in the same manner as PSA, plus the backing is a material easily affected by heat. Add it all up, and we have a material that constantly moves with temperature change- this is one of the reasons we see inconsistencies in the wood coming out the other end, even though we have the drum "dialed in" to the bed.

To make H&L work properly, we need to take advantage of the "cushion" provided. I like to set the bed to where the plate will easily slide under the drum with the abrasive just barely making contact with the wood at the highest point. It is never set to where the wood is "pinched" between the drum and the bed. (When the sander is turned on, the H&L allows centrifugal force to "expand" the abrasive out ever so slightly, allowing the abrasive to cut without the pressure created by pinching.)
Few of us plane perfectly flat or parallel, so the high spots or tapers must be dealt with by multiple passes without changing bed height. Only after the abrasive is no longer making contact with the wood (sometimes, depending on the wood, I will mark with a soft pencil) will I move the bed up, and then only a couple thousandths at most. Usually when I make a bed adjustment, I shut the machine off and do it the same way as when I started- slide the plate under the stationary drum and adjust to where the abrasive is barely making contact.
When the plates are how I want them, I change to finer grit and repeat the process.

Yes, many consider this a slow process, but it gives considerably less headaches with excellent results for a shop-built machine.

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Always have plenty of sandpaper; it's rough out there!

Thanks so much for that Robert. I really did not know all that about drum sanders. I will take it to heart.

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