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May 8, 2014 at 7:53 pm #49038
I have been trying to turn steel. I have not been able to make a smooth cut. Every cut looks like fine threads. I tried higher speed. faster feed, slow feed high speed. every time I get a rough cut. I have sharpened my cutter, used oil, still the same problem. I had the arbor that holds the strike hammers, snap off today( not my clock), and I would like to try to make a new one. This customer is one of those fussy guys that really likes to here his clocks chime 😯 I am using a 1/4″ weld steel to make the piece. Also, can some body explain how to turn a 2& 1/2″ long piece, and have it come out the same thickness from one end to the other. I am using a Taig lathe. I do have a steady rest, but I have not figured out how to use it When I tried to use it there was no room for the cross slide Mahlon
May 8, 2014 at 8:45 pm #57597Mahlon I use one of these. http://www.taigtools.com/c1151.html When I use the live center I always use a center drill to make a dead center dimple for the tip to fit in. I like turning between centers because it is very stable. One thing I have found is if you take a big cut the piece can flex which will give you that thread look if not using a dead center. Flex can also cause your piece to not be the same diameter from end to end. I only use the steady rest after I have cut the piece down to size and then start cutting the pivots on the ends. Then I burnish and polish the pivots using the steady rest. Also if I need a piece 2 1/2″ long I will cut a 3 1/2″ piece. I use the ER collets and let 3″ stick out and again using the live center. I use the minimum amount sticking out of the collet as I can. I have found even at 1/4″ if you have more that 3″ sticking out of the chuck/collets you can still get flex.I found 1000 rpm and a slow feed rate works best for me. Hopefully others with more metal working experience than me will chime in.
May 8, 2014 at 9:43 pm #57598Mahlon,
It looks like the steel you are cutting is about one notch away from coat hanger wire. Some steels turn beautifully and leave a shiney finish while others rip and tear when a cutter is put to them. You might consider buying a length of decent tool steel (drill rod) and see if that will give you better results. Also, consider purchasing a lathe tool that uses the throw away carbide inserts. They are available in small sizes for a lathe the size of your Taig. Enco sells them as well as drill rod.
davidMay 9, 2014 at 12:11 am #57599Hi Mahlon,
make sure your cutting bit is on centre, too low or too high and you will have problems with a good finish.
Paul.May 9, 2014 at 3:47 am #57600Thanks guys. I greatly appreciate your advise. I will try to get the drill rod today. There is a small machine shop down the street from me, I’ll see what she has in stock first. I may take my lathe with me and have her take a look at it, to see if I have it setup right while I am there 😯 Mahlon
May 9, 2014 at 8:05 pm #57601@david pierce wrote:
Mahlon,
It looks like the steel you are cutting is about one notch away from coat hanger wire.
david😆 I think I’d better check myself for a wet spot this just struck a funny bone 😆
Mahlon, I suffer the same my friend so thank you for asking the tough question
May 10, 2014 at 1:12 am #57602Another question I just thought of Mahlon is how deep a cut are you trying to take? If you are trying to remove too much material in one cut this can also lead to problems?
Paul.May 10, 2014 at 7:47 pm #57604After three tries, I finally finished it. I finally figured out that what I thought was a sharp cutter, was really not that sharp. After sharpening the cutter, raising the speed and taking smaller cut, with a faster speed, I was able to at least get it smooth enough to be able to polish it up. It’s not perfect, but I think I can smooth it up a little with a little emery cloth. Then came the next problem. How to drill to 3/32″ holes in it. I tried several time with a scrap piece of rod, but I am afraid my old bench top drill press has a little bit of wonder in it. It was like trying to stab a piece of raw spaghetti with an ice pick So I made up a gig for my Taig lathe. I took a piece of oak, milled it to form a tee on the table saw. Then I mounted it in the tool block and used the cross slide to make a series of holes across the block with the drill bit in the head stock. That gave me a center to make a groove for the rod. Once I put a clamp on to hold it in place, I was able to drill one hole, loosen the clamp and rotate the rod about 30 degrees, and move the cross slide over for the next hole . Probably not very impressive to you guys that have all the good tools, but it works. Necessity Really is the mother of invention Mahlon
May 10, 2014 at 8:24 pm #57605Great solution! We learn more when we have to invent a method and maybe a jig to get the job done.
DanMay 10, 2014 at 9:26 pm #57606Great Mahlon. Glad to see you came up with a great idea. Glad you figured out the bit. I know when I first started I ordered a cutting bit and went to town. I was ready to chuck the whole lathe it made me so mad. A old machinist came over and first thing he said was, ” boy ya gotta sharpen this thing.” 😆 So the first thing I do before I ever start is sharpen my bits.
May 11, 2014 at 12:02 am #57607Hi Mahlon, well done for getting the job done
Did you start the holes with centre drills? This makes it much easier and they are quite cheap! I have this set – http://www.ebay.co.uk/itm/RDGTOOLS-12PC-CENTRE-DRILL-SET-AS-USED-ON-MYFORD-LATHE-/350476831745?pt=UK_Home_Garden_PowerTools_SM&hash=item519a0c0c01
Paul.May 11, 2014 at 3:43 am #57603Thanks Paul, now I really feel stupid. I have several of those in my bit box. I acquired them with boxes of junk that I have bought over the years. I thought they were counter sinks, so I after your post, I went to look, and sure enough, they are centers 🙄 Mahlon
May 11, 2014 at 5:16 am #57608Mahlon great job buddy, and a nice bit of McGyverism on your invention The good news is, I’m learning from your trials & tribulations and to me, that is a wonderful thang, so feeling slightly stoopid should be replaced by feeling slightly proud …
May 11, 2014 at 9:23 am #57609Thanks Chris, it’s amazing what poverty produces. There was a time when instead of going out and buying the newest and greatest tool was not an option. I have learned over the years that with a little thought I can make do a lot of the time with what I have. I bought a wood shaper several years ago, to make moldings. I have only used it a couple times. Either I don’t have the right cutter and have to order it, or I make it on the table saw. Years ago I thought that I needed a band saw to cut circles. An old carpenter that taught me to build cabinets, showed me how to do it on the radial arm saw. Since then, I have leaned that there is a gig that can be built to do just about anything, instead of buying a tool that I may never use again Mahlon
May 11, 2014 at 9:57 am #57610Mahlon,
Radial arm saws when set up and adjusted properly are incredible tools. There are a couple of videos on Youtube showing some of the things these machines are capable of, such as being set up as an overhead adjustable cutter angle moulder. There is also an old out of print video by Curtis Eplinger showing that incredible joint and dato work can done on these machines. Sadly, most of the newer woodworkers coming up have no knowledge about these tools and in fact use a bandsaw for almost everything. Like many large powerful fast moving machines, radial arm saws can be extremely dangerous if safety precautions are not followed. It always puzzled me however that most woodworkers consider router tables, band saws and table saws to be safe machines, and radial arm saws and shapers dangerous. The actual injury numbers show that they are all dangerous.
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