Reassembling a Strip Sander

[JPG]

You're lucky that you have metal idler wheels. I use my sander quite a bit and even though keeping up with the lube on the idler wheel bolts, I have worn out the brass bushing (in the wheels) and destroyed two wheels - so far.

Guess I shouldn't run the sander over an hour at a time.

FWIW I use the plastic/bushing idler at the upper(inside sanding) position(mounted permanently) since I do not care for the abrasive side to wear down the metal ones(nor the metal dulling the abrasive).

I already had one, but since I recently got this one I decided to 'document' the reassembly of it. Neither shall leave here with metal/bearing idler pulleys.

Wish I had the one I already sold with metal idlers back!:rolleyes:

[eartigas]

This post came at the right time for me. Thanks!
I started cleaning and doing basic maintenance to my latest acquisition and noticed that my strip sander idler wheels are plastic with bushings. I am attaching some photos and request advice if they should be replaced or can still be used although their surface is rough. Bushings seems to be OK....for now.
All the equipment I got in this purchase is dated 1993.

[JPG]

I think the important thing is the condition of the bushing. As long as the bushing is not worn and causing the pulley to wobble and the belt tracks correctly over it, all is well.

Granted they appear rough, but IMHO that does not matter.

Those bushings need to be oiled often. Just putting oil on the screw head is not enough. The oil needs to be between the screw shank and the bushing.

[eartigas]

Thanks for the advice, I'll do a proper lubrication before using it. On another note, my sander came only with the half round platen; I ordered the 1 inch flat one and for $11 I got it in a few days. Good to know spares are available.

Ed

[JPG]

[quote="eartigas"]Thanks for the advice, I'll do a proper lubrication before using it. On another note, my sander came only with the half round platen]

There is also a 1/2" wide one.

[mrhart]

JPG nice tutorial, now I NEED a stripsander.

But why isn't it hammered gold!

[charlese]

Only plastic idler wheels are available anymore. That's what I have:( . When doing inside sanding, I quickly wore down two wheels - bought replacements:) . Now use my sander quite a bit. Only for outside sanding.

I just bought a replacement wheel for one where the bushing got loose and began to wobble. Later, I'll show a pix of what happens when the idler wears out. I thought I had oiled enough, but guess not:eek: . Still like the strip sander for sanding toys and for sharpening.

Supposed to oil every 10 hours, but evidently that's not enough when sanding for over an hour at a time and going for 10 such sessions.. I need to learn to shut down the headstock once and a while.

Now have a new cover and a new wheel.

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[charlese]

Thought I'd post this where it belongs:o

Just couldn't stand continuous replacements of plastic idlers wheels. At a cost of $14 each (more if you need to replace the little plastic washer) and shipping, I've already spent over $100 just to keep the machine running. Also spent some more replacing the plastic outside cover. (damage shown in above post)

So ordered up a pair of idler wheels from Sunray Inc. Costly? Yes! but no more plastic wheel, and cover replacements. I've also found that belt tracking is a lot soother with the new wheel.

I believe the plastic wheel is designed for failure, as the 1" axle and bushing are off set about 1/2" two the inside. This forces all tension pressure to the outside of the wheel causing that part of the bushing to heat and the plastic to melt. (See the first two pics) First is showing the inside of the plastic wheel. Second is showing the outside of a plastic wheel. Note the brass bushing had become very loose and fell out.
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Now a photo of the new wheel, which has steel ball bearings. The inside race of the bearing just slid onto the 5/16" shoulder screw, so I sawed up the old bushing and sanded it to hold the wheel away from the inside wall and aligned to the drive wheel. Also just long enough so the shoulder bolt, when nested against the back, will put just a little pressure on the inside bearing race to keep it from rotating freely.

Measurements of the new wheel are 1.875" in diameter - 1.1875" wide. The inside race of the bearing is 5/16" I used an 1 1/2" long shoulder screw. This is the longest that will fit inside a closed cover.
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[rcplaneguy]

Let us know how those new wheels work after you have a few hours on them!

[JPG]

FWIW

The metal rollers are 1 7/8 0D, but with a roll off at the sides to 1.839 from about 3/16 to 1/4 in from the edges. Semi-crowned.

The width is 1.000.

The internal bearing is a 6203 (17 x 40 x 12).

The mounting center is a tight fit to the id of the bearing with a 1/4 hole for the mounting screw.

The mounting center extends beyond the roller side by 1/4.

The recessed end of the mounting center is 5/16 in from the roller side.

The mounting screw is 1/4 - 20 x1 1/2.

P.S. I consider design intent of the off set mounting center is to provide 1/4" clearance to the casting boss it mounts to and 5/16" as clearance for the screw head.

P.P.S. I consider the bushing bearing in a plastic roller to be inadequate. The drive wheel has an od of slightly over 4" so the idlers rotate 2x faster than the drive. At 2000 rpm, the idlers rotate at 4000 rpm.