Fluting columns?

[myxpykalix]

I'm confused about how i can run flutes down and around a column like a traditional column straight down. The "forney fluter" looks like it will only do flutes on flat pieces. Under the indexer I tick "turn traditional flutes, spirals or rings"
It asks about "number of times pattern wraps around blank" ect so i don't think that will work either. My interpretation of that is like if you are making a spiral. Thats not what i want in this case.
Seems to me you need to take the diameter of the column and the diameter of the bit and the distance between each flute and figure out how many flutes will equally go around column. I may be getting hung up on terminology within these tools as to why i don't understand. Any clues guys? thanks

[bill.young]

John,

Here's the section on fluting from the traditional lathe turning patterns section of the Indexer instructions...

"If you want to do fluting, set the Length value to the length of the flutes, the Turns value to 0, and the Copies value to the number of flutes that you want around the blank."

So you were correct. If you're doing flutes you don't want it to wrap around the blank at all, so you would set the turns, the number of wraps around the blank, to zero.

Bill

[bill.young]

Also if you hover your mouse over those input boxes you'll get tooltips with more information about each setting.

[myxpykalix]

I think i understand regarding length, turn value to 0, but what i'm confused on is "copies value" my column now is approx. 6" diamter (19" circumference), my round nose bit is 3/4" diameter. So rather than picking an arbitrary number how would i know how many flutes for my "copy value"?
And with a bit change I have to re Zzero to center of material to be able to get proper depth of flutes, correct?
Another thing occurs to me. If you look at the picture you will see where the joints are it is very thin. How can I determine a start point and number of flutes to be able to avoid those joints? (Is your head aching yet?)lol.
Thanks for your help with this Bill.

6530

[ed_lang]

John,

We talked about using the top of the indexer motor as the point to place the Z-zero plate when I was over. Bill had posted in another thread that doing this and making a new zzero file with the value of the zero plate equal to the distance from the center of the spindle to the top of the Z-zero plate will get this done for you. It would even be easy to call a Custom Cut file to move the X and Y to the proper place, prompt for plate in position, plunge and set Z zero.

Your picture looks good and has a lot of detail in it. Glad the picture posting is working good here.

[bill.young]

John,

Do you know approximately what spacing you're looking for between the flutes? In your case you're pretty much committed to a number of flutes that's divisible by 4 so that you can avoid the thin sections, so you're probably looking at either 8, 12, or 16 flutes.

In general to find out how wide the spaces will be between the flutes, multiply the width of each flute by the number of flutes that you want, and then subtract that from the circumference of the blank. That will tell you how much of the column is "un-fluted" which is the total that's left for the spaces. Divide that by the same number of flutes and you'll get the with of each space. Whether you pick 8, 12, or 16 is up to you...it all depends on the look you want. I'd suggest doing a drawing to confirm your decision...it never hurts.

Because of the thin sections in your blank you'll have to do an extra step when you get ready to do the fluting. Start with one of the thin sections at "top dead center" and zero the B axis. Since you need to make sure that you don't flute one of the thin sections, you need to rotate the blank so that the middle of one of the spaces hits the thin sections and not a flute. Divide the number of flutes that you decided on into 360 degrees to find out how many degrees there are between flutes, then divide this by 2 to find out where the middle of a space will be. So if you decided on 12 flutes, 360/12 = 30 and half of that is 15 degrees. Turn the blank 15 degrees [MB, 15] and then zero the B axis again with a [ZB]. Now when you cut the fluting it should miss the thin sections...here's a picture to hopefully make it clearer


6531

[myxpykalix]

Bill,
You know the old saying " a picture is worth a thousand words"? Well its true in this case. Your illustration made all the difference to my understanding. Here is what i ended up with. I am going to post some pictures in a tutorial i'm putting together based on your info. I wouldn't have gotten this right without your help so THANK YOU!

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