Sliding Table for Belt Grinder

[downsizingnow48]

I use a 2x72 belt grinder a lot, it is very versatile and powerful. I decided to make a sliding work table to improve accuracy on some operations.

Photo 1 - this is the fixed work rest I made when I first got the grinder. 1/2" aluminum. It is much larger than what is normally used but handy for many things.
Photo 2 - I installed 20mm rails and linear bearings for the slide mechanism.
Photo 3 - the work table is 3/8" aluminum. I put a grid of threaded 5/16" holes so standard milling machine hold-downs can be used on large or irregular work pieces. It is also drilled to accept a sliding T-nut extrusion.
Photo 4 - T nut extrusion installed. I am making a long bread slicer knife from a power hack saw blade. It is fixed to the extrusion with three clamps made from 1/4" steel.

With this setup it is easy to get a perfect bevel on the 20" knife blade. As well as perfectly square and even finishes on other workpieces.

The 2x72 grinder works well enough that I sold my Baldor wheel grinder which I never touched after getting the belt grinder.

 

[Big Barn]

Excellent build Pat. In essence you have a very nice surface grinding jig for your belt grinder

I am in other process of designing mine. I would really like to find a magnetic chuck though.

 

[downsizingnow48]

Thanks Big Barn!

I have thought of a magnetic chuck too. Large ones are costly. I have seen DIY setups using rare earth magnets but not convinced that is the way to go.

This setup favors bevel grinding. Next step for me is to set it up so that it fits on the grinder when the grinder is laid down horizontal. That will be a very close approximation to a surface grinder.

 

[user.69169]

Sweet idea. How big de loaf you slice wid 20" knife?

Magnetic chuck easy, look at magnetic door holding locks. Cheap, couple guys already build magdrills from dem.

Nice part of going to electromagnet is you can pulse wid AC and shed grinding dust.

Next you can add operator from commercial sliding electric door to move bed baack and forth at even speed.

 

[texasranger556]

I like it! Looks like the same SBR20 rails I just bought for a project, amazing how cheap they are.

 

[downsizingnow48]

Sweet idea. How big de loaf you slice wid 20" knife?

Magnetic chuck easy, look at magnetic door holding locks. Cheap, couple guys already build magdrills from dem.

Nice part of going to electromagnet is you can pulse wid AC and shed grinding dust.

Next you can add operator from commercial sliding electric door to move bed baack and forth at even speed.

I'll have to check out the door holding locks, thanks for the tip!

 

[downsizingnow48]

I like it! Looks like the same SBR20 rails I just bought for a project, amazing how cheap they are.

Yep I think the prices have come down dramatically in the last several years.

 

[user.69169]

Once die is paid for price of extrusion stays same till competing extruder gets in game.

I like round shaft & linear bearings better then fancy T post.

TIP- you want to make slider fast & easy use real T posts and bearings from wheelbarrow or garden tractor steering tires. Won't be as tight but will serve many places. Works real good for torch or saw sled.

 

[downsizingnow48]

I got the sliding table set up to work with the grinder in the horizontal position. It removes material very fast and accurate. I debated making a fine adjustment mechanism to move the table toward and away from the belt, but decided for starters to just move the tool rest arm in and out. That works but is too clunky. So the next step is to make a screw in/out adjuster.

 

[kennyd]

Excellent! Great idea!

I also use my 2x72 all the time.

Old video I did on mine, it's changed a bit since then:

Grinder in a Box (GIB) Build, Details and Operation. - YouTube

 

[Big Barn]

I got the sliding table set up to work with the grinder in the horizontal position. It removes material very fast and accurate. I debated making a fine adjustment mechanism to move the table toward and away from the belt, but decided for starters to just move the tool rest arm in and out. That works but is too clunky. So the next step is to make a screw in/out adjuster.

Totally looking forward to what you come up with for feed adjustment. Again, nice work so far

And I know you did it a while back but I love your vertical to horizontal mechanism.

 

[downsizingnow48]

It is very sturdy!

 

[varmint]

That's a beautiful machine. My dad, after he retired in the 70's, started making knives again and needed a belt sander to shape blades and grips. (He had begun in 1945; as the manager of the propeller rebuilding shop at the Pensecola Naval Air Station, he had time on his hands as the need for pilot training, and fixing bent propellers, waned at the end of the war. He had steel car springs, aluminum and bakelite to play with.) (I should add that the prop factory was mostly "manned" by Navy Waves, making his war service probably the best period of my dad's life!) He made his own 2" x 72" belt sander, which I have and use today. My only issue is this: I had purchased 36 various grade industrial quality belts in the 90's, and they are now breaking at their seams from time to time during use. It's a shame since about half of them are unused. Anyway, they are extremely useful machines that more people should consider.

 

[downsizingnow48]

Excellent! Great idea!

I also use my 2x72 all the time.

Old video I did on mine, it's changed a bit since then:

Grinder in a Box (GIB) Build, Details and Operation. - YouTube

That is one of the machines I looked at when deciding what to buy.

 

[downsizingnow48]

I had to order some specialized hardware for the fine adjustment mechanism so that took a couple days. Installation took two minutes if that. Didn't even have to drill any holes. I am using a sort of turnbuckle with ball ends. The threads are 1/4x28. I calculate that a 1/12th turn of the turnbuckle (half a flat) translates into about .011 movement of the roller. For this type of operation, poor man's surface grinder, the angle of the belt doesn't matter. What matters is engagement of the roller to the material.

Anyway it works well. I added a couple handles for ease of use, probably safer too.

I still want to add another motion to the work table (to get both x and y motions) but that can wait until I figure out a good way to do it.

 

[downsizingnow48]

For a cross slide mechanism, I found this on Amazon. For the price you could hardly buy the components, let alone build it.

Linear Stage Actuator 1mm Ballscrew 165 Double Optical Axis Linear Rail Guide Manual Slide Stage C7 with Ruler for CNC Router Z-axis: Amazon.com: Industrial & Scientific

 

[downsizingnow48]

This is my V2.0 adjustment mechanism. The first one worked on the belt wheel arm. This one works on the tool rest arm, in both upper and lower mounts. It also uses a 1/4 x 28 threaded rod. The fine adjustment for this machine only has to move 1/8" or so. More elaborate mechanisms are not needed.

 

[Rustyiron]

Very nice projects - both of you!
Just subscribed to Kenny's YouTube to have a better look later.
You guys and your "operating room" clean and organized shops do kinda pizza me off...
(at myself )
Have you seen the guy on yt that built the "go cart belt grinder"?

 

[downsizingnow48]

I decided to install a proper slide on the work table. It is from China and very well made. No play anywhere. Linear bearings for the slide mechanism and a ball screw for the movement. For $150. I could about buy the materials for that and then still have to make it. I also got a magnetic door lock for use as a magnetic chuck. I am still thinking how best to mount it. I need to keep everything interchangeable to easily switch from one work holding adapter to another, depending on the material and operation.