Belt sander grinding belt wears off quickly 2

[hkmensing]

Dear All,

We are buying belt sanders from a factory (we are a trading company), but in tests we have had done, the grinding belt wears off quickly.
The test report states that this is because the pulley is smaller than the grinding belt.
Besides changing the pulley, are there other ways to improve the wear and tear of the grinding belt?

Cheers,

GM

 

[MechEng13]

hkmensing,

What you have described is a Belt Sander. To really understand why it is wearing out so fast we need to know what you are sanding on it. If you are using it to sand metals, yes the belt will wear very quickly. The principle behind the belt is that particles of abrasive are attached to the backing with an adhesive. When you sand something with the belt the particles are knocked off as the rub against the part.

To know if there is a way to improve this we would need to know the material you are sanding and what your definition of "belts wearing off quickly".


HTH


Alan M. Etzkorn
Product Engineer
Nixon Tool Co.

http://www.nixontool.com

 

[hkmensing]

Dear HTH and others,

The material that is sanded is steel. The reason I'm saying that it wears off quickly is because we use a reputable testing lab to test them. They tell us that the grinding belts wear off quickly.

I've found some data where it suggests using graphite embedded cloth pad instead of a steel plate (at the bottom, right under the grinding belt) to improve sanding quality. It might also help increase the time the grinding belt can be used, since friction is reduced. Anyone agree with that?

Cheers,

GM

 

[EdDanzer]

Please describe the abrasive used, belt size, pulley sizes, belt speed, and hp of the drive.

 

[timlin]

Hi
I have the same problems as an end user. I believe there is a woven, stainless steel, mesh belt which replaces the normal grit on cloth type of belt & is almost indestructable. I have not been able to find a supplier yet, can anybody help?

 

[diamondjim]

I think for anyone to determine
answers to your problems you might
be more specific as to drum size,
drum material, the belt width,
the rpm, grit size, type of belt,
etc. of what you are using,
and also the hardness of the material
you are sanding or polishing.

 

[ornerynorsk]

Anything containing abrasive is going to wear out. The platen does not matter much except in heat dissipation. The better machines use a polished cast-iron platen, not steel. Can your testing company quantify and compare what they mean by "quickly"? I use belt sanders nearly every day in my shop, and I go through a helluva lotta belts! Zirconium oxide is supposed to last longer than aluminum oxide, but I can't relate actual experience on that.

 

[Reggie1968]

emory cloth holds up better than most anything

 

[Metalguy]

Hmmm, I thought that emery was an inexpensive abrasive that didn't last too long.

Any other opinions on this?

 

[arto]

Could be that the undersized rolls are "breaking the back" of the belt [kind of like when you fold sandpaper in half to tear it.
A thinner belt thickness [belt/binder/substrate] would have less relative "fibre" stretch as it goes around the rolls. Or a more flexible binder.

 

[griffengm]

hkmensing,
From my limited experience with abrasives I've seen three basic failure modes: The grit fills up with ground material, The abrasive bonding breaks down, or the abrasive loses it's cutting edges. From your description, it sounds like it is the bond breaking down and allowing the particles to come off the belt.
Each of the failure modes has its' own causes and remedies so it pays to know which one is active.
When you say "pulley" do you mean the drum around which the belt moves or do you mean the pulley that drives the drum around which the belt turns?
Speed in surface feet per minute, pressure of the work against the belt, orientation of the work all play a significant role in performance of any abrasive. Anything that generates excess heat is undesirable and reduces life.
To answer your question, yes there are a lot of things you can do.

Griffy

 

[Voyager687]

Many people make the mistake of thinking that one sanding belt is about like any other...and they are not. Sanders from overseas(typically China,Taiwan,Korea,etc.) usually come equipped with very low cost,low quality belts.Domestic mfrs. are about the same. The belt material, abrasive grain, bond,coating and more affect belt life and efficiency. Norton Abrasives makes an EXCELLENT, LONG LASTING belt with zirconia grit. They cost 2-3 times as much as mid-priced(not cheap import} aluminun oxide belts but are still a bargain. Check the MSC catalog for Norton SG series belts. Also, the graphite pad works very well to keep belt temp. down and improve finish, but can make it nearly impossible to keep metal surfaces flat. Sometimes this is actually an advantage if you're only trying to give steel an attractive finish without worrying too much about flatness better than stock CRS. Finally, coolant always helps belt life and finish{if bond is compatable) but can be fairly messy.

Alan L. Bass, toolmaker

 

[BillPSU]

What are you doing with the belt, machining the part, deslagging the part, removing sharp edges, polishing or what? I agree with Voygager687. There are some excellent abrasive belts on the market along with some very poor ones. Each application is different and each supplier has different abilities for making belts. Technology must be applied properly even in grinding belts.

I've machined gray iron castings removing .060 stock per pass with an abrasive belt machine and I've deslagged plasma cut parts and hand ground welds and prepped for paint.