~$200 range disk sander

I'm not following your wiring? Eiter the motor or the VFD has to be on the center terminals. Can y ou post the wiring diagram that came with the switch.

Basic wiring of a three-phase reversing switch:
The numbers used below are for example and may not match your switch. Use the switch contact diagram to wire properly!
You put the wires from the VFD on the center set of terminals. Let's call them 4-5-6)
You put the motor wires on one of the end sets of terminals (call them 1-2-3)
You put jumper wires as follows - 1 to 4; 2 to 6; 3 to 5. This will reverse the direction of the motor.
With the switch in the "1" position, the motor runs one direction; in the "2" position it is reversed. In the "0" position it does not run.
 
Stacy E. Apelt - Bladesmith said:
I'm not following your wiring? Eiter the motor or the VFD has to be on the center terminals. Can y ou post the wiring diagram that came with the switch.

Basic wiring of a three-phase reversing switch:
The numbers used below are for example and may not match your switch. Use the switch contact diagram to wire properly!
You put the wires from the VFD on the center set of terminals. Let's call them 4-5-6)
You put the motor wires on one of the end sets of terminals (call them 1-2-3)
You put jumper wires as follows - 1 to 4; 2 to 6; 3 to 5. This will reverse the direction of the motor.
With the switch in the "1" position, the motor runs one direction; in the "2" position it is reversed. In the "0" position it does not run.
Click to expand...
So the motor did not exactly come with a manual. I had to search for videos on how to set it up and use the graphics from the Amazon page.

Here is best I can do to show how it’s set up right now:

https://imgur.com/a/hgAnZjj

Now that I think about it I’m not sure the way I set it up makes much sense. I currently have the motor wired to one position and the VFD wired to another position. Im still not sure I’m really understand how this switch is supposed to be wired. The switch has 4 sets of spots for wires, with 2 of the sets connected to the “1” position and the other 2 sets connected to the “2” position.
 
A schematic of that switch will be needed to figure out what you are saying. You might be wise to get a friend who understands wiring to help you.

As far as the wires go, the ones you used when it was running are the same ones used to and from the switch.
 
I'm down in NOLA, but pulled up the diagram and that type switch is somewhat different than what I use. I use a reversing drum switch, which just has connections for the three power wires and the three motor wires.

Yours will require jumpers to make it switch from forward to reverse. Here is a diagram of that type switch.

From what I see in the wiring chart you posted:
In position 1 the connected terminals are 1-2, 5-6, 9-10. In position 2 the connected terminals are 3-4, 7-8, 11-12. That would control two separate devices easily (vertical and horizontal disc sanders).

To use it as a reversing switch for three-phase:
1) Wire the three wires from the VFD (L1, L2, L3): L-1 to 1 and 3; L-2 to 5 and 7; L-3 to 9 and 11. Use jumpers to connect those terminals together.
This puts the incoming power on terminals 1 and 3, 5 and 7, 9 and 11 depending on the switch position.
2) Wire the three wires from the motor (A, B, C): A to 2, B to 6, C to 10. Jumper those terminals: 2 to 4; 6 to 12; 10 to 8. That should switch the leads B and C in the reverse position #2.

It's early and I am heading out, so hopefully someone will double check those connections.
 
Thank you! Yeah this was a bit of a head scratcher when I was trying to figure it out.

I’ll write it all out on paper first then work on setting up the jumpers.
 
https://imgur.com/a/cy8zzz6

I finished getting those jumpers set up last night. I watched the copper contacts that flick into position from turning the switch to position “1” or “2”. That set up makes a lot more sense now, sorry about that I was really struggling to understand the mechanics of the switch for some reason. But your explanation helped a ton and it all made sense once I got it laid out.

I just have to connect the VFD and the motor wires where they need to go and it should be all set. I tried to leave as much space as I could so all the wires will fit in the housing together, so hopefully it’s all organized well enough.

I’ll try to get it all hooked up when I got time over the next few days, can’t wait to get this thing ready to go!
 
Stacy E. Apelt - Bladesmith Stacy E. Apelt - Bladesmith

Thank you all so much!

https://imgur.com/a/TMntP7l

It’s all ready to go!!! Forward reverse is all hooked up properly now, the VFD is all set. It’s ready to rock and roll!

Over the next few months I’ll spend a little time here and there attaching any shielding needed while not blocking airflow to the VFD. Then later on I’ll be working on figuring out a tool rest that will fit my bench.

Now I’m finally back to making knives after playing electrician for a few weeks,
Kevin
 
https://imgur.com/a/lOczVDe

So I got to use the sander more this morning and the chatter is worse than before I put the shaft key in. So I go to remove the key and it’s jammed in there really tight… does anyone have any tips on how to get it out?

I plan on just shaping a new key out of a piece of micarta, so if I have to drill it out or something it’s not a big deal. I just don’t want to damage the shaft or the disc itself.

Edit: I guess I should have tried this before posting. Just sprayed some wd-40 onto the key and the disc slid off around it.
 
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I like to lay the key flat on a clean, sharp file.

with even presure I true up the sides of the key, taking off any dings, nicks, or burs. Gliding it across a few times on each side of the key

you should never pound a key into the assembly. Everyone does it, and it bugs me! :/
 
I see the problem in your photo. The disc hub is larger than the motor shaft. That makes it run eccentric.
You will have to make a shim of thin metal that covers everything but the keyway. It will be very thin. I would try a strip of stainless HT foil to start with.
If that does not solve the issue, the hole may be worn off-center. A new disc would be the answer if a shim does not solve the issue.
 
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Stacy E. Apelt - Bladesmith said:
I see the problem in your photo. The disc hub is larger than the motor shaft. That makes it run eccentric.
You will have to make a shim of thin metal that covers everything but the keyway. It will be very thin. I would try a strip of stainless HT foil to start with.
If that does not solve the issue, the hole may be worn off-center. A new disc would be the answer if a shim does not solve the issue.
Click to expand...
think what you’re seeing is the shadow of the shaft sitting proud of the disc face along with the bevel of the end of the motor shaft. When I was trying to get the disc off i accidentally pushed it further down the shaft not thinking, which made the shaft stick out a but. I should have taken more pictures from different angles. When I put this disk onto the shaft it actually shaves the aluminum of the disc hub. It’s kinda a pain getting this thing on and off because of how tight the fit is.

I’m also noticing compared to other motor keyways around my garage that this disc doesn’t have any key way with it. So I have to thin out the keys I have by over 50% to fit this disc onto the shaft.
 
https://imgur.com/a/7PY1EmG

Here are some pictures of how much of the correct size key I have to remove to fit. The last picture is showing how the shaft cuts into the inside of the disc hub when i tap it onto the shaft. There’s no cutout in the disc hub for a key. I’m not sure the best way to grind down the key to fit, tried filing the first time but it would take a day to file it down to 50%.

This is a 3/16”x3/16”x1” key, the kit I have doesn’t have a key that is the same width but thinner. Maybe I need a different type of key?
 
Ah, yes, I see that the disc is just attached by the set screw. Forget about a key in that situation and just lock down the set screw in the keyway.
If the disc is warped, you can't do much at home to correct it, so try the pencil test and see if it is true. You would need to get someone with a lathe to true it up, or replace it if it is warped.
 
I’ll give it a try with no key in again. Is there anything I can do to make sure the set screw threads dont eat up the key slot in the shaft? There are some marks on the walls of the slot in the shaft from the set screw from when I first set up the disc without a key.

I’ll try out the pencil test. if I really need to I’m sure there’s a machine shop some where here in the Louisville area that would be able to resurface it
 
Don't worry about the set screw burring the keyway, just tighten it well.

If you have a good micrometer, measure the disc hub hole and the shaft to see how close they are.
 
Just wanted to update this one while I remember to. Had to move across town suddenly a few months ago (crappy landlord, me and my girlfriend had to get code enforcement involved…). So I had to once again pack up all my smithing/knife making equipment, at least not across multiple states this time.

Somehow I managed to save up some money during all this and I snagged a 9” flat disc from Beaumont. No more chatter on the disc, super easy to remove sandpaper from the disc now too. Man I have no idea how I made knives before having a variable speed disc, it’s truly amazing. I took an old blade from my reject drawer ( really wonky bevels) and brought it to life. I’ll post some pictures this afternoon.

I can’t thank you all enough for the help, this really was a big step in knife making for me! So much easier to get nice flat bevels and a clean finish. 9x11” sheet is easy to find cheap around me too, saving lots of money on abrasives now!


Kevin
 
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