New RPI 2X72

OK, so just Googled KBAC VFD and this popped up! Well I can't figure out how to get a screenshot to work on this but here is the search.

https://www.google.com/search?q=KBA...e..69i57.1884289j0j7&sourceid=chrome&ie=UTF-8

So on that search, there is 5 different units across the top and five different prices and more if you click on the arrow on the right side. So what are we looking at here??? What is recommended???

Also I got to ask what is the big advantage to a variable frequency AC drive?? I mean I may see some of the advantage especially with handle material but how much can you slow down grinding steel till you aren't really cutting any more!!

Now remember sometimes you don't know you are missing something till you get to try or see it in action. I saw one set-up over at Ken's in Bama but, didn't get to see him on it or try it! So I am really trying to understand what the VFD does!!!

There are a few applications where I slow the belt down slow enough to read the writing on the back of the belt when it goes by. VS is worth EVERY penny it costs.
 
There are a few applications where I slow the belt down slow enough to read the writing on the back of the belt when it goes by. VS is worth EVERY penny it costs.

So I get that you can slow it down and in some ways I see where that can be handy. What kind of operations are you doing when you do the slow down, I guess that is what I am trying to figure out????

I know some types of wood do not like fast speed but, there has got to be more that the average maker is using that "slow-down" for, to justify the cost!!

At present I am running a 2hp, 220V, 1725 RPM, and using the three step pullies and I will admit I have found the occasion to wish that I get it down a little slower but, as the consumer I have got to understand the benefits enough to justify the cost!!!

I saw the one KenH has in operation, not in use. He could make it nearly crawl! However that is where you loose me, what are you doing when it is crawling!!
 
C Craft, I usually run mine at slow speeds when I get the dreaded 2" bump, groove..or what ever you want to call it. we all know what it is. sometimes I'm at the point where if I get that 2" thing going on, I'm almost done or am done with the bevels. that's when I'll run a 400 grit gator belt and go over my bevels at slow speed to remove any defects. doing it at a high speed your likely to be removing more steel than you really want at the stage your at.
 
Cliff, The really big advantage of VFD is when grinding bevels and wanting to "touch" for a small correction or fix to the blade. Crank that thing up to 4,000 sfpm for profiling, then slow down a bit for grinding bevel. As the bevel gets close, slow down more for that fine edge on the bevel. Also, when grinding post HT, you can control the heat so much better at slower speeds.

Also, a 60 grit belt will handle high speed, but put a 400 grit belt on and it will burn before you know it if not slowed down. Best thing by far is for you to drive over again to spend the day making a couple of blades on my grinder. Of course, realize it's gonna cost you when you go home and order that 3 ph motor and VFD.... about $300 for both motor 'n VFD budget price shipped.
 
You can also run the motor in reverse. I plan on getting the Reeder sharpener, it's like A GIANT LANSKY SHARPENER, but with a 2HP motor!!
 
I use the slow speed for finishing thin (less than .010") blades at high grit. For instance, a 2" wide chef knife made from 3/32" stock with a FFG gets hot FAST, especially at the edge because there is so little mass. The higher the grit the slower I run them. I grind bare handed in order to feel the heat so it also helps keep my thumbs from getting blisters. I have thick callouses on my thumbs and when they get hot they're like a pair of hot gloves that you can't yank off. LOL
 
IT'S HERE IT'S HERE! Went home today for lunch my grinder wss on the porch!! I only had a few minutes to look but the thing looks beautiful. Machine work looks awesome detail looks good too!! More to come!!
 
I REALLY like the looks of that grinder! I like it! I'd not paid much attention how those were put together before. So much attention to detail. I like the way it's designed for horizontal work, nice design. After you use it some, tell me if you find that latch to lock tension arm down very useful. I can't imagine any need for it..... except perhaps when leaving grinder for a long period use the lock to remove tension from belt rather than releasing tool arm. BUT - that would then hold tension on spring. I like the idea of removing tension on everything for overnight.

If I were to build another I think I would use that design. Looks like it would be pretty easy to build.
 
There is a lot to like about that grinder! One thing (as silly as this sounds) that jumps out at me is the width of the wheels on the platen attachment. On my KMG, I have always thought the wheels were a little too narrow. The belt always seems to be rolled over slightly on the edges. Seeing these wheels on your grinder makes me think I need to make some wider wheels and see if there is any improvement.
 
There is a lot to like about that grinder! One thing (as silly as this sounds) that jumps out at me is the width of the wheels on the platen attachment. On my KMG, I have always thought the wheels were a little too narrow. The belt always seems to be rolled over slightly on the edges. Seeing these wheels on your grinder makes me think I need to make some wider wheels and see if there is any improvement.
The Grinder did not come with wheels, they do have an option for that though. The wheels I purchased are Oregon Blade Maker "Lightning Wheels" 5" drive, 3" tracking and 2" platen wheels. They are all 2-1/4" wide. The maker told me that these Glass injected wheels were superior to Aluminium in every way! I believed him because they were half the price and Oregon Blade sold both! REEDER also sent Brass spacers for the Platen wheels if you use narrower 2" wheels. I'm a couple weeks off but I will be ordering a small wheel adapter and the 23" arm for Large wheel and their sharpening system. All in good time. Just need to get it up running and practice!!
 
You did the right thing, IMO. You can do 90% of whatever you need to do with a flat platen. It takes longer to hog off metal on a flat platen than it does with a big contact wheel, but you can still do it. A contact wheel gives you more options for contouring and profiling. A small wheel makes life so much easier for internal radiuses, but you can still do those without a small wheel.
 
You did the right thing, IMO. You can do 90% of whatever you need to do with a flat platen. It takes longer to hog off metal on a flat platen than it does with a big contact wheel, but you can still do it. A contact wheel gives you more options for contouring and profiling. A small wheel makes life so much easier for internal radiuses, but you can still do those without a small wheel.

After doing my blades on a file jig this thing will be AWESOME!!
 
I use my small wheel attachments MUCH more often than I do the 8" or 10" contact wheels. One of the best things I've made is the small wheels.
 
Eventually I will get all the Bells and Whistles! Small wheel adapter and wheels first, then a 10-12" contact wheel and a 23" extra arm for their sharpening system. I'm using a Lansky now it works pretty good but takes a long time!! I can't wait to get it up and running. Probably by a week or more. Lot going on with the close of Summer!
 
You should be able to make the tool arms yourself and save a bit of money. The small wheel adapter isn't hard at all to make either. The wheels are a tad harder to make without access to a lathe.

You gonna really enjoy that grinder!
 
Back
Top