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View Full Version : Advice on sandpaper for drum sanders requested



Vespa Bob
09-11-2014, 01:01 PM
While waiting for the finish to dry on my second Favilla style teardrop uke, another story entirely, :( I decided to tackle the task of building a drum sander. After much trial and tribulation, I finally succeeded and I'm at a point where I'll soon be attaching the sandpaper. I have done some research and know that there are basically three types of paper and their respective methods of attachment: Velcro backed, adhesive backed and plain backed, all supplied in rolls. It would appear that the velcro type is the easiest method to apply plus it also adds some cushioning, but it is also expensive. Adhesive backed paper sounds like a pain to remove and I have no idea how one would attach non sticky backed paper. So I turn to the experts to advise me on the type you use and why. I'm ready to learn something new! My roller is 4" diam. and 12" long. Thanks.

Bob

Alain Lambert
09-11-2014, 03:26 PM
I use plain back paper 4 in wide, my drum is around 22 in wide.
I have used hose clamps in the past to attach it. Here is how I attach it now.

70789

ericchico
09-11-2014, 04:00 PM
I use hook and loop. The Velcro from Lowes and I get the abrasive from this place http://www.onlineindustrialsupply.com/3indrsarohlo.html . It is very nice. Easy to change.

RPA_Ukuleles
09-11-2014, 04:26 PM
Press the easy button and use a Shopsmith green Ceramic abrasive belt sander belt from Lowes. I cut the belt at the correct angle, spray the back with spray can adhesive, and wrap around the drum. I also add a few wraps of tape to the ends to keep them from lifting. Simple and cheap, but, and I'm serious here, that is the best abrasive I've ever used. I can't seem to wear it out, and have had no clogging issues. Calculate what size will work on your 4x12 drum, and give it a shot.

70790

Vespa Bob
09-12-2014, 07:43 AM
Three great solutions, thank you guys! Alain, I assume that you don't use any adhesive, only the recess attachment?
ericchico, your link to Industrial Supply Co has good prices, I might give that a try.
RPA, Your system seems cheap and easy, but one question - how difficult is it to remove the old sandpaper when the time comes to change it?
Thanks again!

Bob

Timbuck
09-12-2014, 07:56 AM
When I had a shop built sander with a wooden roller..I found it was easer to fit the belt by using thumb tacks/drawing pins to hold the belt in place while i taped up the ends.

RPA_Ukuleles
09-12-2014, 08:28 AM
- how difficult is it to remove the old sandpaper when the time comes to change it?

It doesn't take much adhesive to hold in place. Just a light mist on the paper, and on the drum is all I do (plus you don't want any lumps). Since the ends are secured with tape, the adhesive mostly keeps it from slipping. Less is more.

ericchico
09-12-2014, 09:25 AM
Three great solutions, thank you guys! Alain, I assume that you don't use any adhesive, only the recess attachment?
ericchico, your link to Industrial Supply Co has good prices, I might give that a try.
RPA, Your system seems cheap and easy, but one question - how difficult is it to remove the old sandpaper when the time comes to change it?
Thanks again!

Bob
The sandpaper they sell is not only a great price but its really good stuff, but I think they have a min order of $35. I bought 2 rolls of 80 and one 150 and had to change out the 80 twice since April, once because I was not being smart and ran a piece through with a snag that tore it up and shot the piece back at me almost making a stain in my shorts. :rolleyes:

FarmerBill
09-12-2014, 09:55 AM
I have a 5" steel drum that I wrap dry, no glue, and duct tape at the ends. I take my time getting a tight wrap and haven't had a problem yet. I use any cloth back abrasive I can find between 80 to 120 grit. It takes a long strip as my drum is 30" wide.

Bill

Alain Lambert
09-12-2014, 11:11 AM
Three great solutions, thank you guys! Alain, I assume that you don't use any adhesive, only the recess attachment?

Bob

That is right, no adhesive. I roll it tight and attach the ends.

lauburu
09-12-2014, 11:22 AM
I built a thicknessing sander using MDF for the drum. Polyurethaned it then used contact cement (not spray on) to attach the sandpaper. Worked well until I had to replace it. It took a whole weekend to peel it all off clean it up and get the drum back to a usable state. Bought a roll of self adhesive Velcro about 150mm wide which I then spiralled around the drum and pinned the ends. Then spent about $100 on a couple of metres of velcro backed sandpaper (3 grits) (Norton I think). Yes it was expensive but the sandpaper is really good quality - it just keeps on going - and changing grits is an absolute breeze.
Miguel

Vespa Bob
09-13-2014, 10:37 AM
Thanks again for all your responses. I think I might initially try non adhesive backed sandpaper and use plastic zip ties to hold the ends down. That should work and it won't be a costly outlay for my test runs.

Bob

Mark Roberts Ukuleles
09-17-2014, 12:56 PM
Vespa Bob,
I build a drum sander about 7 years ago, and fired the wood drum route, in favor of a trued aluminum drum, much like what you'd see on a commercial unit. I found that schedule C electrical aluminum tubing was perfect. It is 1/4" thick tubing, with a 4 3/8" OD.
I cut four 3/4" birch ply circular inserts, center drilled for the 3/4" OD shaft. They were epoxied into place.
The best attachment method I found is the spring assisted take-up clamps that are used on commercial drum sanders.
The can be orders by the equipment distributors as replacements and installed inside the ends of the drum. They keep constant pressure on the sanding abrasive strips.

It is driven by a 1 1/2 HP enclosed and air cooled motor. The motor is mounted on a hinged mooting platform, so the hanging weight of the motor tension the drive belt. Works great.

While on the subject of drum sanders...I had used the typical precut abrasive strips for years, until I found a superior abrasive.
I am a big fan of Mirka abrasives and learned that they make abrasives for automotive work. You may be aware of their Abranet line of abrasives
Well, they make it in rolls that are perfect for the drum sander. It turns out to be less expensive and far superior to a traditional abrasive. It is a mesh material and has much higher tolerances to the abrasive. You won't find that most of the abrasive is say 100 grit with a few 60 or 80 grits dropped in like most brands, leaving unwanted gouges. Their 100 grit leaves a surface more like 150 grit, yet removes material faster and easier. Since it is a mesh material, it also stays cool and greatly reduces oily wood residue build up on the abrasive, like others tend to do. In fact, I can say that I have yet to have a residue build up like I had from other typical abrasives.
[ATTACH=CONFIG]71029

RPA_Ukuleles
09-18-2014, 02:51 AM
MRU, Thats good to know. I've always liked the Abranet abrasives. Also good tip on the aluminum tubing.

I love the hand written reminder on the sander shroud "Stiffness-not thickness" Now that says it all.

Vespa Bob
09-18-2014, 08:10 AM
Thanks, Mark, for that advice. Since I haven't yet bought sandpaper, in fact I haven't even finished truing the drum, I'll look into the Mirka abrasives. What grit should one start off with to remove most of the material before going to a finer grit?
Bob

Mark Roberts Ukuleles
09-19-2014, 06:33 AM
I typically use the Mirka Autonet P80. It is a Euro P80 grit, removes material like an 80 grit, but leaves a finished surface like a 100 grit.
By the way, another product I will recommend becoming friends with is "Shim In A Can". It is a stainless machinist
shim stock, and yes, it comes in a can. You can get it in a wide range of thicknesses.
I use it with my drum sander to add as shims under the pillow block bearing, to dial in very close tolerances between the drum and support table for your stock beneath it.
Before doing that though, I used a 1/8" hardened Masonite board covered with 100 grit sandpaper glued on with spray adhesive.
With no abrasive on the drum, I run this Masonite board between the drum and the table to true the surface of the drum to the table so they are parallel. Then I took a sacrifice board, and feed it under the drum, with the drum mounted with sanding abrasive. This is with the drum turned on and spinning. Next, mark across the surface of the wood with a marker for reference.
Take a light pass, to judge how even an parallel the drum is.
Now take a micrometer and measure the thicknesses of the wood stock on the left and right side of the wood stock. It they are not very close, add some shim stock under the appropriate pillow block to raise it a bit.
Repeat until you end up with even side-to-side thickness. You should be set after doing this.

The other great benefit for Shim In A Can is that it is an ideal bending strap for side bending. Same stuff that StewMac and LMI sell for much more. I typically buy it in .008", .010", and .012" thicknesses. Comes in 6" x 50" rolls for about $17 - $20 a can.
Will not cause a chemical stain on woods, like some other metals will.
71066

Vespa Bob
09-19-2014, 06:10 PM
Thanks for the info on the grit numbers,I'll be ordering some soon. I have already trued the drum using the method you described and so far have no need to add shim, but will keep the "Shim in a can" in mind for future use..