Home built 2" x 72" belt sander project

[Meridian_Mike]

I hunted and I searched the net for a DETAILED plan of how to build a 72" belt sander..... WITH DIMENSIONS...
SO..... after some weeping and gnashing of teeth, I researched the topic in several areas of the www net, I came up with this.....
If y'all want to add or subtract you are welcome to do so.

I HOPE this will help someone get a 2" x 72" sander on their bench at a minimal cost....

ANYWAY.... here is a layout WITH DIMENSIONS of the sander I hope to build .... LOL.... I drew up this sketch so I would have something to go by for my build.
(that detail in the lower left of the plan, is a section thru the main body of the frame.)

The plan.....

The total length from the back of the motor to the front of the grinding surface should be about 2'-3" to 2'-6" or there about.

I researched the motor and it looks like the other builders prefer an electric motor somewhere in the 1 HP to 3 HP range. It is hard to find one that powerful that will just plug in to a household socket (120V)... SO, I had to jump up to a 240V motor. They also suggest a TEFC motor to keep grind dust out. I found a bunch on ebay that sells electric motors for a reasonable price.
I got this one on the way for a total of $133.17 SHIPPED to me.....

It is a Surplus Western (Brook Compton) 1.5 HP 230/460 volt, 3 phase, TEFC (Totally Enclosed Fan Cooled), 3600 RPM motor.
It has a 7/8" diameter shaft.

I got myself a 4" solid aluminum drive wheel from Origin Blade Maker (dot com). They have all the parts you want to make your sander OR you can buy the whole thing motor included from them somewhere in the $1200 to $1500 range (that is why I am building mine!)
Here is the drive wheel.....

I got all the wheels from OBM because the price was good and I didn't want to try to find or made a set of wheels that would be precision quality for this project.
That being said, I got the adjustable tracking wheel from them also.... It is already mounted and hinged. All I will have to do is weld it on the upper tensioning arm and make an adjusting screw.

Another part I ordered from OBM was the front backing set-up with wheels already mounted and an adjustment slot cut into it. I saw all sorts of tutorials about how to make this MAJOR part but for $94 I got it from OBM and it is READY TO GO.....
This one is steel but you can get one from them that is aluminum.

I finally found (some place on the net) where a guy spec-ed out his gas piston spring. He said his was a 30 pound piston. (I would imagine 20# to 30# would be fine) SO.... according to my plan, I need one that is somewhere in the 7" to 10" range. SO, I found this guy on the bay. it is 10" fully extended and 7" compressed. I should be able to work with that.
The seller had all strengths and lengths. I got this one on it's way to me for $21 shipped.....

I thought about buying a tooling arm from OBM ... They have this one for $36 plus some shipping. That would add up to be somewhere close to $50 in my hands....

BUT.... I thought about it and figured I would just make my own. I ordered this piece of aluminum tube from a guy on the bay for $19 shipped. I figure I can drill it and make it like I want.
It is 1 1/2" square tube x 24" long. (generic picture)....

SO... here is where I stand so far, with the (I sorta think) major parts secured.....
Electric motor ...... $133.17 (shipped)
OBM parts ........... $225.00 (shipped)
Gas spring ........... $20.89 (shipped)
Aluminum tube ..... $18.45 (shipped)
----------------------------------------------
Total thus far....... $397.51 invested

NOW...... short of buying bolts, turn handles or what ever else I want to use to dress this guy up with, .... I plan to build the balance from metal I can get here at my place of business FOR FREE ..... (that is the price I like to pay for stuff....LOL). You can do similar by using scrap materials.

I have the 2 main side pieces being cut out as we speak from 1/4" plate on our CNC machine.... (YES, that is cheating!! )
The rest I will dig out of the scrap bins. Far a finished build, I hope all else I will have to do is, cut, drill, weld and bolt together.

Stay tuned for further developments.....

[Jeffinn]

Looks great so far Mike! I’m looking forward to seeing the final build!
Jeff

[orvet]

That looks good Mike except I am wondering if you are going to put a speed control on it?
My 2 x 72 is a Grizzly, which is admittedly a minimal 2 x 72, it only runs at 1700 RPM... I would hate to see it running at 3200 RPMs!
I am afraid it would be way too fast for finish work, though it might work great for hogging a lot of metal off quickly though.
The faster it goes, the more heat it generates, that's what what concerns me about it. Aside from that I think it looks great and the price is outstanding, about what I paid for my Grizzly 8 or 10 years ago. Of course they are much more expensive now!

I'm not an expert on 2 x 72 belt sanders, but it looks like a solid design. You should certainly have enough power with that 3 HP motor! I have more than enough power with mine with just a 1 HP motor, I have never needed more power with mine. I like your idea of the TEFC motor, if it gets enough air for cooling should last longer by reducing the grit that gets in it.

Be sure to post pictures when it's done, I can't wait to see it!

[Meridian_Mike]

I'm glad you brought up the speed issue Dale.
I do have plans (in my head) of putting some sort of motor speed control on it some time in the future. I have seen one that seems to be a heavily used controller and prices for it run in about the $250 range.

I am still investigating this angle but..... YES..... I do want to add a speed control before it goes into full time use on my bench.

In my reading and searching for ADVICE and parameters for my build, it seems the criteria I have found says you want to run between 2500 and 4000 SFM (Surface Feet / Minute)....
I THINK the 2500 SFM would be about 1700 RPM..... MAYBE...

SO, what I have right now without a speed control will be about
3200 RPM which will be.....
3656 SFM and that equates to
a SCREAMING 42 MPH.... That's in a hurry!!!

I have a couple of options bouncing around in my head...
An inline electrical speed controller ....

OR ....

a step down pulley system. I thought about a set of pulleys on a shaft with corresponding pulleys on my motor. That way, I can manually select my belt speed.

Like this here...

motor-pulley-250x250.jpg (10.12 KiB) Viewed 9392 times

Here is a NICE speed calculator....
http://dcknives.com/public/belt_speed.php

I am still undecided on this issue.....

[orvet]

The pulley system is what I use to control the speed of my homemade buffer and both my drill press work on the same step down pulley system as well. It works well for the buffer, I am not sure how well it would work for a belt sander. It might start slipping at some point, especially if it's not tensioned properly. I think if you built in a good system of tensioning the belt, that would work fine.

[Meridian_Mike]

The pulley system is what I use to control the speed of my homemade buffer and both my drill press work on the same step down pulley system as well. It works well for the buffer, I am not sure how well it would work for a belt sander. It might start slipping at some point, especially if it's not tensioned properly. I think if you built in a good system of tensioning the belt, that would work fine.

Yep, I am sure belt slipage could be an issue.
I have seen some other builds that used a pulley system to get the sander belt speed they wanted. Looking at the calculator, I see that a 2" pulley at the motor and a 4" sheave at the drive shaft, there would be a reduction of belt speed to about 1746 RPMs (or 914 SFM). That sounds like a good speed according to what you are working with.

This system would give me a 4 speed sander where the variable speed controller would have endless possibilities....

The jury is out.....

[Doc B]

I would never be able to draw "the plan"...much less implement it! Very impressive start! Can't wait to see it!

[Jeffinn]

The pulley system is what I use to control the speed of my homemade buffer and both my drill press work on the same step down pulley system as well. It works well for the buffer, I am not sure how well it would work for a belt sander. It might start slipping at some point, especially if it's not tensioned properly. I think if you built in a good system of tensioning the belt, that would work fine.

Yep, I am sure belt slipage could be an issue.
I have seen some other builds that used a pulley system to get the sander belt speed they wanted. Looking at the calculator, I see that a 2" pulley at the motor and a 4" sheave at the drive shaft, there would be a reduction of belt speed to about 1746 RPMs (or 914 SFM). That sounds like a good speed according to what you are working with.

This system would give me a 4 speed sander where the variable speed controller would have endless possibilities....

The jury is out.....

My Coote belt grinder has the pulley system on it for speed control. To be honest, it’s set at the lower speed and that’s where I leave it because I just haven’t had a need for the higher speeds. The motor is on a simple pivot which provides the necessary belt tensioning. For a belt I use a power twist variety similar to this one which minimizes vibration and allowed me to lengthen or shorten the belt as needed: https://www.rockler.com/1-2-power-twist ... gKHf_D_BwE
If money is no object then the electronic controller is a great way to go otherwise the pulley system will suit your needs just fine.
Jeff

[Meridian_Mike]

My Coote belt grinder has the pulley system on it for speed control. To be honest, it’s set at the lower speed and that’s where I leave it because I just haven’t had a need for the higher speeds. The motor is on a simple pivot which provides the necessary belt tensioning. For a belt I use a power twist variety similar to this one which minimizes vibration and allowed me to lengthen or shorten the belt as needed: https://www.rockler.com/1-2-power-twist ... gKHf_D_BwE

If money is no object then the electronic controller is a great way to go otherwise the pulley system will suit your needs just fine.
Jeff

LOL.... yep, at my house money is DEFINITELY an object.....LOL.
I just bought a few more parts for a pulley sheave system so I am going to try to step down the speed that way.
With a 2" pulley on the motor and a 4" step pulley on the sheave I should get close to the 1750 RPM speed.

The one I ordered for the motor keeps a 2" pulley for 2 positions....

Then, the one for the sheave will be a step down pulley. It has a 4" as the largest and a 2.5"" as the smallest.

According to the calculator, I can get about a 1828 SFM (surface feet per minute) step down with the 4" pulley. With the 2 part pulley at the motor, I can get at least 2 speeds with this set up.

AND... good point about the motor being on a pivot. I think I can do that ....... and let the motor weight be the tensioner.... Thanks for the idea Jeff.

For now, this is all an experiment for me. I should be able to eventually get something that pleases me. I'm sure the first attempt at the build won't be final. BUT, at least I can make changes to the original as I go.

[Meridian_Mike]

The site I have been using as a reference for my build (Origin Blade Maker) suggests you want a target speed of 2500 to 4000 Surface Feet per Minute or SFM.
I used the calculator (I posted a link to earlier in the thread).....
Here is what I found my belt speed possibilities will be with the pulleys I have coming.....

2" drive pulley on the motor (which will be producing about 3600 RPMs).
THEN
with a 4" drive wheel at the belt....
and the step pulley at the other end of the shaft with 2 1/2", 3", 3 1/2" and 4" slots .....
I am looking at getting these results.....
.

.
SO.... looks like I will have at least 3 possibilities that will be SLOWER than the suggested speed and 1 that will fall inside the target area but at the low end.
I have no idea what this will be in RPMs.....

We shall see.

[Montanaman]

Is that motor a 230 single phase and 460 3 phase? or 230/460 3 phase? Do you have 3 phase in your shop? Great project

[Meridian_Mike]

230/460 3 phase?
Do you have 3 phase in your shop? Great project

Yep, I have 3 phase in my shop.....
Well, it's in the breaker box.....

It should be a fun project!

[Meridian_Mike]

Is that motor a 230 single phase and 460 3 phase? or 230/460 3 phase? Do you have 3 phase in your shop? Great project

Well.... after a lesson about power from my electrician friend..... It turns out I only have SINGLE PHASE power to my shop.
I'm glad you brought that up Montanaman.....!! THANKS!!

SO.... once again, back to the ole drawing board!

I am going to have to have a VFD (Variable Frequency Drive) to power this motor.

With that on my mind, I started looking around for an AFFORDABLE (for me) VFD.
I have found a few in the $100 range, BUT BEFORE I PULL THE TRIGGER and buy one..... I am going to make SURE it will power the motor and perform like I want.
More to come......

[ReidJustin]

Hmm ... an Interesting scheme, but I'm not sure how good your sander will be. Usually, such tools are of high accuracy and quality, which is the main thing when creating such a tool.

[Colonel26]

Mike I’m definitely interested to see how this turns out. I’ve been tempted several times to try one of these myself, but just haven’t gotten my round to it’s top line up. Keep the pics coming!

[zed6309]

Mike I'll be following this closely as I've wanted to improve my belt sander for a few years

[Meridian_Mike]

Hey everyone....
I am a little bit behind in my projects so this one hasn't moved in a while.
.
I have almost all the parts now so construction should start soon.
I will try to take pictures as I go so I can show my success (or failures).....

[ReidJustin]

Hmm ... an Interesting scheme, but I'm not sure how good your sander will be. Usually, such tools are of high accuracy and quality, which is the main thing when creating such a tool.

I do not have enough skills to create such a tool on my own and I think that it is not cost-effective, since it takes a lot of time and consumables. It seems to me that it is much easier to buy a finished product that will be guaranteed by the manufacturer. As a woodworker, I always choose quality sanders for myself, as these tools show the results of my work. All you have to do is visit this site and get the best recommendations for choosing a sander that meets all your conditions.

[Tony_Wood]

Looks like a great start to the project.

Can’t wait to see it finished. Those hollow tool arms will vibrate. I filled mine with a 2x2 that is cut to fit and drove inside. That helped with vibrations.

[Meridian_Mike]

Those hollow tool arms will vibrate. I filled mine with a 2x2 that is cut to fit and drove inside. That helped with vibrations.

Thanks for that advice Tony!
I can go ahead and do that from the start!

[ReidJustin]

Hmm ... an Interesting scheme, but I'm not sure how good your sander will be. Usually, such tools are of high accuracy and quality, which is the main thing when creating such a tool.

I do not have enough skills to create such a tool on my own and I think that it is not cost-effective, since it takes a lot of time and consumables. It seems to me that it is much easier to buy a finished product that will be guaranteed by the manufacturer. As a woodworker, I always choose quality sanders for myself, as these tools show the results of my work. All you have to do is visit this site and get the best recommendations for choosing a sander that meets all your conditions.

[Meridian_Mike]

Yes, that thinking is true.
.
BUT... I have all the tools to do the drilling and welding and, I work at a steel company so the frame steel was free.
.
AND.... I just want to do it..... you know... The craftsman in me wants to "build my own".

[WhiteUn]

Hmm ... an Interesting scheme, but I'm not sure how good your sander will be. Usually, such tools are of high accuracy and quality, which is the main thing when creating such a tool.

I do not have enough skills to create such a tool on my own and I think that it is not cost-effective, since it takes a lot of time and consumables. It seems to me that it is much easier to buy a finished product that will be guaranteed by the manufacturer. As a woodworker, I always choose quality sanders for myself, as these tools show the results of my work.

Could you tell me some more information about it? Let’s talk in PM

[Meridian_Mike]

Well..... it has been a while but I did find a few hours yesterday to start assembly of my belt sander.
I didn't take a lot of pictures but maybe if y'all want to try it, I can at least answer questions.....
Here is most of the pieces I started with......

I got a few pieces like the wheels and such from Origin Blade Maker.....

First thing I did was assemble the frame plates and set the hole for the tool arm so it would move in and out easily with as little slack as I could build in.

Then a good bit of work slipped on by before I took another picture....
I set up the pulley shaft and bearings, and put on the belt drive wheel.
I set the location for the upper wheel and bolted it on the upper tension arm.
I also set up the platform for the motor.

The next parts I put on were the backing plate and wheels and the mounting bracket for the platen.
SO..... with all the wheels in place, I had to load a belt on to see what this contraption was gonna look like....

I made a bracket for the tension piston and got it welded in place. My drill battery died so I figured it was time to call it a day.
Well on my way to having a "sure 'nuff" 72" belt sander!!

More to come when I can get back out there and finish up....

[Jeffinn]

That’s looking really good Mike! Thanks for keeping us updated.
Jeff