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Reel seat insert/lathe turning question
Posted by:
Rick Lewis
(---.boeing.com)
Date: January 23, 2002 10:39AM
My only experience on a lathe is with metal. My question is about grind angle on the tool for turning reel seat inserts. Would a grind angle of 7 to 10 degrees be good for wood? I have looked at some wood gouges and most look nothing like tools for a metal lathe, roughing gouges are "U" shaped. Re: Reel seat insert/lathe turning question
Posted by:
Tom Kirkman
(---.dialinx.net)
Date: January 23, 2002 12:04PM
Yes they are U-shaped but you are not cutting with the entire face, only a portion of it.
Selection of the proper bit, cutting and relief angle and rake are important to get the best results from a machine lathe. We are fortunate that wood is quite forgiving compated to many of the other materials turned and shaped on that style lathe. I could go into several pages of comments on tool bit grinding and what works best for what. But to get you going, try a standard round nose cutting bit, or a standard right hand turning bit. Position your tool holder so that the angled edge of the bit confronts the edge of the wood at 90 degrees. Cut from right to left (towards the headstock/chuck). This same method will work for the shoulder on the right end. Don't cut too deeply on any one pass. Sometimes I make my finishing cut with a square finishing tool that looks much like the standard wood turner's scraper or bedan tool. It can be fed across the insert lengthwise for a very smooth surface (only for a very light cut, however) and can also be fed directly into the insert for cutting shoulders. The only downside is that you must dress the tool perfectly flat on the face, and align it in the tool holder perfectly square, or it will leave cutting marks all along the insert where one corner is doing most of the cutting. You want the entire face to cut. Tools can be on the insert centerline and the standard front clearance of 3 to 15 degrees is fine. There is really no need for any back rake on the tool or the position of it for wood cutting. A sharp bit is one that will cut cleanly. A dull bit (and they do dull quickly) is one that will tear the wood. If you have invested in any type of lathe, you also need to invest in the tools to properly sharpen the bits. As you practice, you will no doubt learn a bit more about which bits work best and what depth of cut is best. When you can "peel" of ribbon of wood shaving off that is several feet long, you're on the money! *(The cut angles I have given you work well on wood, but aren't necessarily what you will want on any type of metal. In fact, you find they will not cut at all on certain types of steel. For more info on cutting bit selection, grinding and use, please get yourself a copy of "How to Run a Lathe" by South Bend. It's an old book but top notch as far as info goes. Most of the metal supply shops carry it.) ................ Re: Reel seat insert/lathe turning question
Posted by:
Scott Brockwell
(---.s58.tnt1.chts.va.dialup.rcn.com)
Date: January 23, 2002 07:38PM
Rick, You can also simply use regular wood turning tools locked onto your tool post. I have a turret tool post and my lathe centers with 3/8ths bits, but I use a regular wood turning gouge for roughing and large dimensional cuts, and then finish with a small skew while the lathe is at its highest speed with the lead screw engaged. I have to shim the tools somewhat to bring them to just above center, but that's simple enough. I get very smooth finishes, even when I've used as many as four different materials of varying composition laminated to create a single insert (such as two types of wood with a synthetic mother-of-pearl-like inlay sandwiched between thin knife handle spacer material -- soft and hard stuff side-by-side that would drive you crazy turning it by hand while trying to get a smooth surface). If you want pictures of the tooling set up in the lathe, or work produced on it, I can e-mail you. It's nice to avoid the hassle of shaping your own tools if you already have any wood-turning tools on hand, or readily available. After all, they are made for the job. Sorry, only registered users may post in this forum.
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