Post by 1dave on Sept 5, 2020 17:15:48 GMT -7
Caught by a WBS (Wet Belt Sander).
It must be a flaw in my DNA, one project seems to always lead into another.
(Another article I thought I had posted on RTH but didn't)The rubber backing on my old Frantom sanding drums got hard and brittle so I searched for repair information. I did a web search and up popped Covington Engineering. To my pleasant surprise Judy, the lady that answered, knew exactly what to do!
While talking to her I foolishly perused the Covington online catalog,
covington-engineering.com/sanders-1/
Call Toll Free: 1-877- 793-6636.
First sight of Covington's #466 WBS and #764WBS wet belt sanders instantly called to my memory the huge units I had seen at glass companies and had previously thought
“What a dandy lapidary unit that would make !”
I was caught hook, line, and sinker, and didn’t even know it!
They are manufactured in two sizes, but sell Silicon Carbide Belts (or diamond if you prefer) in three lengths:
3" x 24" Fit Small Covington Sanders.
3" x 25-7/32" Fit 8" Expandable Drums.
3" x 41-1/2" Fit Large Covington Sanders.
Available in 60, 80, 100, 220, 320, 400, 600, & 800 Grit AND you can Mix and Match Grits when ordering 10 or 50 or more for better prices!
They also have cork belts for pre-polish, and felt belts for final polish. “Let the felt belts dry in place after using or they will shrink.”
This would do the job of the flat lap I’d been considering! This would be great for cab backs, book ends, hmm . . . How could I adapt it for jamb peg faceting, make some “facet-chons” . . .
“Have you considered manufacturing a unit that would take both the 24" and 25-7/32" belts” I asked, trying desperately to wiggle off the hook.
“Yes, we have made them in the past, but most customers didn’t like them. If you want one It will take an extra couple of months to build.”
Resigned to my fate, I at least still had two choices: the mounted ready to be plugged in version, or the basic model that is about $200 cheaper. Could I get a motor, water connections and baseplate for less than that? Cheapskate that I am (check out www.kingsleynorth.com/skshop/product.php?id=46633&catID=1046), I ordered the basic unit.
I know that mostRock and Gem readers are excellent craftsmen, but from time to time a “newbie” will happen by, so I’ll proceed in my analytical style. Analytical?
Ask an analytical what time it is, and he’ll try to tell you how to build a watch.
You have three options on water:
1. Fill the pan and let the sponge keep the belt wet.
2. Attach with 1/4" plastic tubing gravity feed from a nearby water reservoir of some type.
3. Attach with 1/4" copper tubing to a pressure water supply.
Water connections were not a problem. I had a lot of that stuff on hand, and there are plenty of plumbing supply sources around. I did not have a spray nozzle (CSN808) that attaches to the bottom of the water supply L-valve, but as I planned on using a gravity feed with no pressure, I figured I could make something to distribute the water evenly out of a couple of old credit cards and a ty-wrap.
First after introducing the cards to my meteorite hunting magnet to remove all data, I super-glued the two cards together in a tee shape.
Second, I bent the top card in a dust pan shape.
Remember, first things first, but not necessarily in that order. You probably should make the adjustment slot for an 8-32 screw in the other card somewhere along about here.
Third, I bent the bottom card to fit inside the unit by the water entry.
Fourth, I drilled the 8-32 screw hole in the metal cover and attached the device.
Motor? Yes, I needed a 1/3 hp motor.
The lowest price in my area was a two speed swamp cooler motor from home depot ($73.97) + motor base ($10.68) + clamps ($2.94) + 6 position cooler wall switch ($10.96) + handy box, cable, plug, ½" cable clamp connector, pulley and short v-belt from elsewhere.
Two speeds? 1725 (5.5 amps) and 1140 (3.9 amps). Now that would be nice, to slow down while working soft stones like opal so those valuable fire lines disappear a tad slower.
I like it!
As my work bench is 24" deep, I made my base board 10"x24" so any applied pressure will just push against the wall. I don’t have to screw it down and can move it out of the way whenever I want. Different from the factory mounted sander I could have bought, I placed the sander flush with the front of the board so the drain line can drop straight down, marked where the bolt holes needed to be, and drilled them out with a1/4" bit. As I’m using 1/4"x1 1/4" hex head bolts, I flipped the board over and drilled the bottoms of the holes with a 13/32 bit to the depth of the head, then pounded the bolt heads flush in place so they can’t spin around.
With the sander bolted in place, I placed the motor with the belt on, tensioned the belt, assured everything was square, and marked where the motor base bolt holes needed to be. I drilled and inserted the bolts as above.
Belt Info:
How to see properly with a straight edge:
A word about V-belts. The first letter refers to the cross-section measurements, the following number to the inside length of the belt. You want an A belt, ½" wide and 5/16" deep. The length is up to you. Verify the motor and unit shafts are parallel. Use a straight edge to assure the sander and motor pulleys are in perfect alignment.
Pressing down on the belt with about 5 pounds pressure shouldn’t deflect it more than about ½”-3/4". A pulley with adjustable depth is handy to make minor adjustments in belt tension.
All that’s left is the wiring. A two speed motor sounds complicated, but it only adds one wire to a regular motor hookup. Wire size is important. Years ago I bought a used 20" slab saw that had to have a fan blowing on the motor to keep it cool. The motor draws 11.5 amps and was fed with a 20' long #18 AWG cord. #14 should have been used. I use #12 to feed it and have never had a problem with the old motor heating.
#10 wire is rated for 30 amps, #12 for 20 amps, #14 for 15 amps, #16 for 13 amps, #18 for 10 amps. As this motor draws 5.5 amps, #18 would do here, but I’d go heavier.
I drilled two holes on the right hand side of the sander near the top and used two #10-32 machine screws with lock-washers and nuts on the inside so it can’t vibrate loose.
The green ground wire from the power cord connects to the threaded hole at the back of the handy box to ground it with a 10-32 screw and a green ground wire to the motor.
Mandatary Disclaimer: When working with motors and electricity, read and follow all pertinent instructions and safety warnings. Never work with the power connected.
The black wire is the hot feed and can be stripped back an inch and wrapped around the screw for L1, but I prefer using ring or fork terminals, especially on stranded wire.
Only strip back the wire for ½ the distance of the insulated part of the connector, and crimp at the insulated portion closest to the ring or fork. The white, neutral, wire connects to the white to the motor and pump with a wirenut. A little electrical tape around the wire and wirenut will assure it won’t vibrate loose.
Along with the ground wire, another cable is needed to run from the handy box to the motor. The black wire goes from C on the switch to Hi in the motor, the white wire attaches to the C in the motor - NOT to be confused with the C on the switch! The red (or a wire with red tape) connects 1 on the switch to Lo in the motor.
A third cable can be run from the switch to the pump.
Ty-wraps and cable tie mounts make for a professional looking job.
As I operate several machines from the same water supply, I opted to keep the pump separate with just a float switch turning it on and off from my upper reservoir as the water level drops.
My completed unit. There is only one knob to worry about. It is on the top left hand side.
Turn it clockwise to move the belt to the left and tighten, counterclockwise to move the belt to the right, loosen, and remove it.
Sanding above the backplate can stretch the belt and make it wander, so it is a good idea to keep an eye on where the belt hits the bottom drum. Practice moving the belt back and forth to make adjusting it an automatic habit.
How did I ever get along without this?
It must be a flaw in my DNA, one project seems to always lead into another.
(Another article I thought I had posted on RTH but didn't)The rubber backing on my old Frantom sanding drums got hard and brittle so I searched for repair information. I did a web search and up popped Covington Engineering. To my pleasant surprise Judy, the lady that answered, knew exactly what to do!
While talking to her I foolishly perused the Covington online catalog,
covington-engineering.com/sanders-1/
Call Toll Free: 1-877- 793-6636.
First sight of Covington's #466 WBS and #764WBS wet belt sanders instantly called to my memory the huge units I had seen at glass companies and had previously thought
“What a dandy lapidary unit that would make !”
I was caught hook, line, and sinker, and didn’t even know it!
They are manufactured in two sizes, but sell Silicon Carbide Belts (or diamond if you prefer) in three lengths:
3" x 24" Fit Small Covington Sanders.
3" x 25-7/32" Fit 8" Expandable Drums.
3" x 41-1/2" Fit Large Covington Sanders.
Available in 60, 80, 100, 220, 320, 400, 600, & 800 Grit AND you can Mix and Match Grits when ordering 10 or 50 or more for better prices!
They also have cork belts for pre-polish, and felt belts for final polish. “Let the felt belts dry in place after using or they will shrink.”
This would do the job of the flat lap I’d been considering! This would be great for cab backs, book ends, hmm . . . How could I adapt it for jamb peg faceting, make some “facet-chons” . . .
“Have you considered manufacturing a unit that would take both the 24" and 25-7/32" belts” I asked, trying desperately to wiggle off the hook.
“Yes, we have made them in the past, but most customers didn’t like them. If you want one It will take an extra couple of months to build.”
Resigned to my fate, I at least still had two choices: the mounted ready to be plugged in version, or the basic model that is about $200 cheaper. Could I get a motor, water connections and baseplate for less than that? Cheapskate that I am (check out www.kingsleynorth.com/skshop/product.php?id=46633&catID=1046), I ordered the basic unit.
I know that most
Ask an analytical what time it is, and he’ll try to tell you how to build a watch.
You have three options on water:
1. Fill the pan and let the sponge keep the belt wet.
2. Attach with 1/4" plastic tubing gravity feed from a nearby water reservoir of some type.
3. Attach with 1/4" copper tubing to a pressure water supply.
Water connections were not a problem. I had a lot of that stuff on hand, and there are plenty of plumbing supply sources around. I did not have a spray nozzle (CSN808) that attaches to the bottom of the water supply L-valve, but as I planned on using a gravity feed with no pressure, I figured I could make something to distribute the water evenly out of a couple of old credit cards and a ty-wrap.
First after introducing the cards to my meteorite hunting magnet to remove all data, I super-glued the two cards together in a tee shape.
Second, I bent the top card in a dust pan shape.
Remember, first things first, but not necessarily in that order. You probably should make the adjustment slot for an 8-32 screw in the other card somewhere along about here.
Third, I bent the bottom card to fit inside the unit by the water entry.
Fourth, I drilled the 8-32 screw hole in the metal cover and attached the device.
Motor? Yes, I needed a 1/3 hp motor.
The lowest price in my area was a two speed swamp cooler motor from home depot ($73.97) + motor base ($10.68) + clamps ($2.94) + 6 position cooler wall switch ($10.96) + handy box, cable, plug, ½" cable clamp connector, pulley and short v-belt from elsewhere.
Two speeds? 1725 (5.5 amps) and 1140 (3.9 amps). Now that would be nice, to slow down while working soft stones like opal so those valuable fire lines disappear a tad slower.
I like it!
As my work bench is 24" deep, I made my base board 10"x24" so any applied pressure will just push against the wall. I don’t have to screw it down and can move it out of the way whenever I want. Different from the factory mounted sander I could have bought, I placed the sander flush with the front of the board so the drain line can drop straight down, marked where the bolt holes needed to be, and drilled them out with a1/4" bit. As I’m using 1/4"x1 1/4" hex head bolts, I flipped the board over and drilled the bottoms of the holes with a 13/32 bit to the depth of the head, then pounded the bolt heads flush in place so they can’t spin around.
With the sander bolted in place, I placed the motor with the belt on, tensioned the belt, assured everything was square, and marked where the motor base bolt holes needed to be. I drilled and inserted the bolts as above.
Belt Info:
How to see properly with a straight edge:
A word about V-belts. The first letter refers to the cross-section measurements, the following number to the inside length of the belt. You want an A belt, ½" wide and 5/16" deep. The length is up to you. Verify the motor and unit shafts are parallel. Use a straight edge to assure the sander and motor pulleys are in perfect alignment.
Pressing down on the belt with about 5 pounds pressure shouldn’t deflect it more than about ½”-3/4". A pulley with adjustable depth is handy to make minor adjustments in belt tension.
All that’s left is the wiring. A two speed motor sounds complicated, but it only adds one wire to a regular motor hookup. Wire size is important. Years ago I bought a used 20" slab saw that had to have a fan blowing on the motor to keep it cool. The motor draws 11.5 amps and was fed with a 20' long #18 AWG cord. #14 should have been used. I use #12 to feed it and have never had a problem with the old motor heating.
#10 wire is rated for 30 amps, #12 for 20 amps, #14 for 15 amps, #16 for 13 amps, #18 for 10 amps. As this motor draws 5.5 amps, #18 would do here, but I’d go heavier.
I drilled two holes on the right hand side of the sander near the top and used two #10-32 machine screws with lock-washers and nuts on the inside so it can’t vibrate loose.
The green ground wire from the power cord connects to the threaded hole at the back of the handy box to ground it with a 10-32 screw and a green ground wire to the motor.
Mandatary Disclaimer: When working with motors and electricity, read and follow all pertinent instructions and safety warnings. Never work with the power connected.
The black wire is the hot feed and can be stripped back an inch and wrapped around the screw for L1, but I prefer using ring or fork terminals, especially on stranded wire.
Only strip back the wire for ½ the distance of the insulated part of the connector, and crimp at the insulated portion closest to the ring or fork. The white, neutral, wire connects to the white to the motor and pump with a wirenut. A little electrical tape around the wire and wirenut will assure it won’t vibrate loose.
Along with the ground wire, another cable is needed to run from the handy box to the motor. The black wire goes from C on the switch to Hi in the motor, the white wire attaches to the C in the motor - NOT to be confused with the C on the switch! The red (or a wire with red tape) connects 1 on the switch to Lo in the motor.
A third cable can be run from the switch to the pump.
Ty-wraps and cable tie mounts make for a professional looking job.
As I operate several machines from the same water supply, I opted to keep the pump separate with just a float switch turning it on and off from my upper reservoir as the water level drops.
My completed unit. There is only one knob to worry about. It is on the top left hand side.
Turn it clockwise to move the belt to the left and tighten, counterclockwise to move the belt to the right, loosen, and remove it.
Sanding above the backplate can stretch the belt and make it wander, so it is a good idea to keep an eye on where the belt hits the bottom drum. Practice moving the belt back and forth to make adjusting it an automatic habit.
How did I ever get along without this?