Replies

1. 
   Lee_Grindinger | Mar 10, 2002 02:12am | #1

   *
   You're using a scraper. Call it what you like but the action is essentially that of a scraper.

   The slicing action, that action above the center, cuts much faster but your tools have to be in better shape. The chatter you mention is frequently caused by the difference in hardness between early and late wood and once the chisel starts bouncing the motion just continues. Getting out of a chatter requires a very firm grip and the chisel must be held so that the piece is brought back into round. Once round you continue with a very firm grip so the chatter doesn't begin again.

   The scraper is fine as long as you're not trying to remove too much material.

   Lee

1. 
   jack_nissen | Mar 10, 2002 02:40pm | #2

   *hi leetwo more questions with apologies to mike.can it ever be right to stand on the other side of the lathe to remove wood from the inside of what will be a bowl? i do it and it seems to work, but if it is suicide, i will stop.can you describe how to use the taylor loop tool? (super tip 2000).thanksjack

1. 
   Lee_Grindinger | Mar 10, 2002 04:39pm | #3

   *I'm not sure what you mean by "the other side of the lathe", Jack, but you seem to sense danger when you do it so based on that it may be wise to reconsider your position. I try to never stand where an exploding piece can hit me. I've had pieces blow up on the lathe and centrifical force can be great, even at low RPMs. I've patched the holes in ceilings over my lathe and been glad I was clear as the damage was done.Sorry, but I'm not familiar with the Taylor loop tool. Perhaps someone else here is.Lee

1. 
   Mike_Taylor1 | Mar 10, 2002 05:31pm | #4

   *Lee - If I raised the 'scraper' so that it makes contact above center, would I angle it above or below horizontal? The scraper is clamped into the duplicator with about 5/8" of the end of the tool protruding toward the pieces. The scraper is made of 1/8" thick A2. The next time I order more A2 I'm going to get 3/16" thick. I sharpen the scraper on my vertical belt sander (220 grit) set at about 30 degrees and can get about 20 pieces per sharpening. Sharpening takes about 1 minuite. I keep the point as round as I can cause the pin follower is a 1/2" dowel. I get better cutting action if I leave the burr on. The speed I go in cutting the pieces determines how much time I have to spend sanding them afterwards.Basically, I'm just trying to decrease the overall time required and improve quality.

1. 
   Lee_Grindinger | Mar 10, 2002 06:49pm | #5

   *Here's a couple of illustrations for us.This is the angle for the use of a chisel...View ImageThe handle is held low and cutting edge is well above the center of the workpiece. A chisel will leave a smoother surface but it has to be sharp and held very carefully. A chisel will also cut much quicker than a scraper.Below is the angle for the use of a scraper...View ImageA scraper will leave a rougher surface but I don't think you have any options. Because the distance from the peg to the cutting edge is critical in a duplicator you have to use a scraper. There is no way to control the angle of a chisel and still work from a pattern on a duplicator. You'll note that a chisel can be used as a scraper and it's the angle of attack that determines the difference. Even though a scraper can be ground at 20 degrees it will still work as a scraper.There is little question that your tool works better with a burr than without. After all, it is a scraper.Lee

2. 
   Mike_Taylor1 | Mar 10, 2002 09:49pm | #6

   *Thanks Lee. I made a gouge out of the A2 and it does certainly cut faster and cleaner. But, it has to be held at an angle show in your diagram and wouldn't work for a duplicator. I will move my scraper contact point up slightly and see what happens. Mike (guess I need to clean up my vernacular - I just call them all chisels, knives, whatever)

3. 
   Don_Rogers | Mar 11, 2002 11:52am | #7

   *MikeI have a similar copier to what you've described made by a local lathe manufacturer (Durden). The bit is ground at about 10* & rounded as yours is, but the departure is that it is also 'skewed' across the cut at about 10* also. Sill not the best cut in the world but I find that it works for roughing out the general profile which I finish off with conventional tools.Hope this helps.Don

4. 
   Mike_Taylor1 | Mar 11, 2002 06:51pm | #8

   *Don - I measured the sharpening angle on mine yesterday and it is more like 25 degrees. Since my pin follower is a 1/2" dowel rod, I wanted the tip to exactly duplicate that shape. Occasionally I test the shape while sharpening using a short piece of dowel rod. My biggest problem was repositioning the scraper after sharpening. It has to be exactly the right distance to ensure getting the correct diameter for the cut piece. I solved this by making a couple of test pieces exactly 1" in diameter.I also raised the scraper 1/16" yesterday. It didn't cut as well, so I lowered it back to the original position. Right now, it's coming in at dead center and is angled slightly downward.Here's a tip I've learned for turning objects about a center hole. Drill the center hole first, then use pin centers on your head and tail stock that duplicate the diameter of the drilled hole. That way, the turning will be exactly centered on the drilled hole. May sound simple, but took me a while to figure that out. I had to make the center pin for the head stock.