[SCzEngrgGroup]

\r\n \r\n Have you tried taking multiple finish passes, including a final "spring pass"?
\n
\nRegards,
\nRay L.\r\n \r\n

[CadRhino]

\r\n \r\n Hi Ray,
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\r\nOnly on the corner round did I do a finish pass of .003" and I still have those lines.
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\r\nGood suggestion (I should have done it on the rest of the ops but they are not visible).
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\r\nI was just expecting overall better finish.
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\r\nI will add a .003" finish pass to the other ops and that will probably help but I suspect I will still get the lines (just finer).
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\r\nThanks,
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\r\n-Nathan
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Have you tried taking multiple finish passes, including a final "spring pass"?
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\r\nRegards,
\r\nRay L.

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[SCzEngrgGroup]

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Hi Ray,
\n
\nOnly on the corner round did I do a finish pass of .003" and I still have those lines.
\n
\nGood suggestion (I should have done it on the rest of the ops but they are not visible).
\n
\nI was just expecting overall better finish.
\n
\nI will add a .003" finish pass to the other ops and that will probably help but I suspect I will still get the lines (just finer).
\n
\nThanks,
\n
\n-Nathan

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Try taking a heavier finish pass. At 0.003", you may be rubbing. Cutting tools like to have a good "bite", and will often cut better when working harder. My typical finish cut is 0.01". Try both slowing down, and speeding up, feedrate. Depending on conditions, either one can improve finish.
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\nI don\'t know what the quality of the Tormach endmills is, but the specific tool makes a HUGE difference. Those may simply not be very good endmills.
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\nRegards,
\nRay L.\r\n \r\n

[kfriedrich66]

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Try taking a heavier finish pass. At 0.003", you may be rubbing. Cutting tools like to have a good "bite", and will often cut better when working harder. My typical finish cut is 0.01". Try both slowing down, and speeding up, feedrate. Depending on conditions, either one can improve finish.
\n
\nI don\'t know what the quality of the Tormach endmills is, but the specific tool makes a HUGE difference. Those may simply not be very good endmills.
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\nRegards,
\nRay L.

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Umm this contradicts your "spring pass" suggestion earlier which would be removing a minute amount of material and more than likely leave a worse finish.
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\nNathan, are you using a finishing endmill, 4 flutes or better for your finish work?
\nKate\r\n \r\n

[CadRhino]

\r\n \r\n Hi Kate,
\r\nI am using the same tool for rough and finish so I am not switching over to a 4fl for finish but I will do that.
\r\nIt is the chamfering and corner rounding that is getting me. Those are 4 flute and I was hoping for a better (mirror) finish but maybe, like popspipes said, it will always have some lines.
\r\nRay\'s, comments kind of mesh with what Frank Mari (Mari tools) told me today. He said I might want to try 2000 rpm and 30 IPM and mix it up. That my machine might be having a funny \'harmonics\' at 5100 RPM and that I might want to find the sweat spot for each too.
\r\nBest,
\r\nNathan
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Umm this contradicts your "spring pass" suggestion earlier which would be removing a minute amount of material and more than likely leave a worse finish.
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\r\nNathan, are you using a finishing endmill, 4 flutes or better for your finish work?
\r\nKate

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[SCzEngrgGroup]

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Umm this contradicts your "spring pass" suggestion earlier which would be removing a minute amount of material and more than likely leave a worse finish.
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\r\nNathan, are you using a finishing endmill, 4 flutes or better for your finish work?
\r\nKate

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The point, is, you have to try different things. There are countless factors that can affect finish quality, and some can only be found by experimentation. Feeds and speeds that work well on one machine, may be awful on another, due to small differences in the cutting tool geometry, or machine or tool resonances. Even a small change in RPM can sometimes have a large effect. But, in general, tools are happier with a higher chipload. That can be achieved by reducing RPM, or increasing feedrate. If all is perfect, a spring pass can help, otherwise, it might hurt. You just have to experiment, and find what works best for you, with your tool, on your machine. For me, 3-flute tools are rarely an improvement. For others, they are. I also generally get better finish with a 2-flute than with a 4- or even 6-flute. Go figure...
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\r\nRegards,
\r\nRay L.\r\n \r\n

[popspipes]

\r\n \r\n Machine marks will always be present, they get smaller with lower feedrates but never completely go away as they are a function of the cutting action of the cutter.
\nI always take a finish pass on everything of .005 to .01, it does improve the finish.
\nI also have a vibrator finisher with walnut hulls and emery grit mixed with it that works to brighten parts up,
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\nI finish at 5140 rpm and 20 to 35 feedrate but the spindle and drive are balanced pretty well so the finish is better but I still have the marks, they are just more even.
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\nI also use 4 flute cutters for finishing.\r\n \r\n

[CadRhino]

\r\n \r\n Hi Popspipes,
\r\nThanks for the insight.
\r\nI have a Harbor Freight vibrator I have not used yet so this may be a good reason to get it set up.
\r\nWhat kind of Walnut shell and grit do you use and where do you get it?
\r\nThanks for the feedback on feeds and using a 4 flute for finish passes. I have 2 flute beaten into my head for aluminum but that makes sense.
\r\nBest,
\r\nNathan
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Machine marks will always be present, they get smaller with lower feedrates but never completely go away as they are a function of the cutting action of the cutter.
\r\nI always take a finish pass on everything of .005 to .01, it does improve the finish.
\r\nI also have a vibrator finisher with walnut hulls and emery grit mixed with it that works to brighten parts up,
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\r\nI finish at 5140 rpm and 20 to 35 feedrate but the spindle and drive are balanced pretty well so the finish is better but I still have the marks, they are just more even.
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\r\nI also use 4 flute cutters for finishing.

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[SCzEngrgGroup]

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Hi Popspipes,
\r\nThanks for the insight.
\r\nI have a Harbor Freight vibrator I have not used yet so this may be a good reason to get it set up.
\r\nWhat kind of Walnut shell and grit do you use and where do you get it?
\r\nThanks for the feedback on feeds and using a 4 flute for finish passes. I have 2 flute beaten into my head for aluminum but that makes sense.
\r\nBest,
\r\nNathan

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Walnut shells will not take of machining marks unless maybe if you leave them in there for an eternity (days, if not weeks). Plastic pyramids (which must be used wet) will remove machining marks in 1-2 hours, leaving the surface looking like it was media blasted. It will also remove burrs, and put a very small radius on all the edges. You can then polish it using ceramic balls or rods with a fine abrasive (dry), and finish polish with walnut shells and rouge. But the last two polishing steps will still take a day, perhaps two. And, you can\'t put a lot of parts in each run, or they\'ll scratch each other up.
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\r\nRegards,
\r\nRay L.\r\n \r\n

[popspipes]

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Hi Popspipes,
\nThanks for the insight.
\nI have a Harbor Freight vibrator I have not used yet so this may be a good reason to get it set up.
\nWhat kind of Walnut shell and grit do you use and where do you get it?
\nThanks for the feedback on feeds and using a 4 flute for finish passes. I have 2 flute beaten into my head for aluminum but that makes sense.
\nBest,
\nNathan

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walnut shell I got from Harbor Freight, the emery I had from years ago, It can be bought at a supplier that handles polishing grits.
\nMachining only goes so far, the marks get smaller but never all go away, If I were going to polish the radius on that part I would put it in the lathe max spindle speed and use a 3 m metal finishing wheel mounted on an angle grinder at reduced rpm, a few minutes of this will give it a matte finish and will remove the tool marks, if you need a mirror finish, go to jewlers rouge or emery and a rag wheel. All polishing takes some time, the more mirror finishes take the most time.
\n
\nMost of my aluminum work doesnt need polishing as the guys that buy it want to see the machine marks, they just have to look nice and not have any burrs.
\n
\nI have used many 3m polishing wheels on stainless parts and piping, they are the best period, that I have found, also the most expensive.
\nThe most even way I have found to polish a part is to rotate it (lathe) and use a rotating 3m wheel on an angle grinder at reduced speed. I never did much aluminum polishing except for my hobby parts, most of mine was done on stainless tanks and piping.
\nThose 3m wheels I used work equally well on aluminum, it just cuts much faster than stainless.
\n
\nThere are many ways of doing it, you just have to find the way that suits you.
\n
\n3M sells many wheels for metal finishing, the one I used mostly was a 2S FN 6" or 8" x 1/2" x 1"arbor hole, the last ones I bought were around 60 dollars each, that was almost 10 years ago.
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\nI would say that buffing that part in the lathe would take less than 10 minutes on the radiused end only, if its aluminum, once you get the hang of it.
\n
\na piece of emery paoer would do the job on the lathe as well but would take longer, and is a bit more work.
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\nI am kind of new to the vibratory finishers, and I am sure there are better ways than mine, I just dont know what they are ha!!\r\n \r\n

[CadRhino]

\r\n \r\n I have thought about chucking the parts on my metal lathe to sand/buff them but the thought that was getting any grit in my ways always stops me. I know I can clean it up every time but just a little grit missed could wreck havoc on the ways.
\r\nI have a wood lathe I might try it on.
\r\nHow do you hold the demurring wheel when it is on your lathe or do you use it on a seperate tool?
\r\nThanks
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walnut shell I got from Harbor Freight, the emery I had from years ago, It can be bought at a supplier that handles polishing grits.
\r\nMachining only goes so far, the marks get smaller but never all go away, If I were going to polish the radius on that part I would put it in the lathe max spindle speed and use a 3 m metal finishing wheel mounted on an angle grinder at reduced rpm, a few minutes of this will give it a matte finish and will remove the tool marks, if you need a mirror finish, go to jewlers rouge or emery and a rag wheel. All polishing takes some time, the more mirror finishes take the most time.
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\r\nMost of my aluminum work doesnt need polishing as the guys that buy it want to see the machine marks, they just have to look nice and not have any burrs.
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\r\nI have used many 3m polishing wheels on stainless parts and piping, they are the best period, that I have found, also the most expensive.
\r\nThe most even way I have found to polish a part is to rotate it (lathe) and use a rotating 3m wheel on an angle grinder at reduced speed. I never did much aluminum polishing except for my hobby parts, most of mine was done on stainless tanks and piping.
\r\nThose 3m wheels I used work equally well on aluminum, it just cuts much faster than stainless.
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\r\nThere are many ways of doing it, you just have to find the way that suits you.
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\r\n3M sells many wheels for metal finishing, the one I used mostly was a 2S FN 6" or 8" x 1/2" x 1"arbor hole, the last ones I bought were around 60 dollars each, that was almost 10 years ago.
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\r\nI would say that buffing that part in the lathe would take less than 10 minutes on the radiused end only, if its aluminum, once you get the hang of it.
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\r\na piece of emery paoer would do the job on the lathe as well but would take longer, and is a bit more work.
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\r\nI am kind of new to the vibratory finishers, and I am sure there are better ways than mine, I just dont know what they are ha!!

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[Steve Seebold]

\r\n \r\n You can get walnut shell with rouge at your local gun shop. It\'s primarily used for polishing brass for reloading. I use it to polish some of the aluminum parts I make for my model boat running gear. It had absolutely no debarring qualities. I use it only for polishing. I have 2 Burr King vibratory tumblers. One is a 3 quart and one is a 10 quart. I use the 10 quart one for debuting and the 3 quart one for polishing. When I put parts in the polishing media, they will often run for up to a full week.\r\n \r\n

[pickled]

\r\n \r\n Agreed with the comments above. The other piece to verify is that you are at the shortest stick-out of the tool that you can get for your set-up. I typically only give my tools a reserve of about 0.015" in length to get a high finish job done. Expensive carbide tooling is nicer in this regard, but it even likes to be choked up a bit in the holders. Your radius cutter did quite well and a little bit of hand finish or walnut lovin\' should make that area shine. What DOC were you using for your chamfer and how high was your contact point?\r\n \r\n

[CadRhino]

\r\n \r\n I had the chamfer up .02" and added another fudge factor of .02" stock to the chamfer so it was .03" up from the tip of the chamfer tool. I use sprutcam so that is the formula I used so it was not cutting on the tip.
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Agreed with the comments above. The other piece to verify is that you are at the shortest stick-out of the tool that you can get for your set-up. I typically only give my tools a reserve of about 0.015" in length to get a high finish job done. Expensive carbide tooling is nicer in this regard, but it even likes to be choked up a bit in the holders. Your radius cutter did quite well and a little bit of hand finish or walnut lovin\' should make that area shine. What DOC were you using for your chamfer and how high was your contact point?

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[MichaelHenry]

\r\n \r\n To me, it would be a lot easier (and faster) to get a good finish on parts like that with a lathe, either CNC or manual. If a dull matte finish, rather than bright, is acceptable than you might try tumbling the mill-machined parts.
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\nMike
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\nOn edit: Using the Tormach as a lathe, as others here have shown, might also be a good solution.\r\n \r\n

[CadRhino]

\r\n \r\n Agreed but I am going to be doing quite a bit of work on the back sides and I only have a manual lathe which I am not terribly fast on.
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To me, it would be a lot easier (and faster) to get a good finish on parts like that with a lathe, either CNC or manual. If a dull matte finish, rather than bright, is acceptable than you might try tumbling the mill-machined parts.
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[CadRhino]

\r\n \r\n I would love to start using my mill as a lathe but since I am using the tts system (and atc) I think the best I could do is to put a 1/2" diameter into a 1/2" tool holder.
\r\nIf I didn\'t have the atc and PDB I could put a r8 chuck in the spindle. Do you know if any alternates ways?
\r\nThanks
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To me, it would be a lot easier (and faster) to get a good finish on parts like that with a lathe, either CNC or manual. If a dull matte finish, rather than bright, is acceptable than you might try tumbling the mill-machined parts.
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\r\nOn edit: Using the Tormach as a lathe, as others here have shown, might also be a good solution.

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[MichaelHenry]

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I would love to start using my mill as a lathe but since I am using the tts system (and atc) I think the best I could do is to put a 1/2" diameter into a 1/2" tool holder.
\nIf I didn\'t have the atc and PDB I could put a r8 chuck in the spindle. Do you know if any alternates ways?
\nThanks

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You can still put an R8 chuck in the spindle, it will just be more hassle. That is more hassle than I want to put up with so the Slant Bed Lathe is probably in my future.
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\nMike\r\n \r\n

[CadRhino]

\r\n \r\n Really?
\r\nI thought I would have to take the whole PDB out to be able to chuck up a standard r8
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You can still put an R8 chuck in the spindle, it will just be more hassle. That is more hassle than I want to put up with so the Slant Bed Lathe is probably in my future.
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[G59]

\r\n \r\n You should try a 3 flute endmill. This was discussed in another thread how the spindle harmonics affect finish. The 3 flutes create their own harmonics but at different frequencies. This difference in frequency can sometimes dampen or even cancel each other out eliminating tool marks.\r\n \r\n

[CadRhino]

\r\n \r\n Thanks G59.
\r\nI actually have a 3-flute roughing E.M. I bought from tormach and will try it.
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You should try a 3 flute endmill. This was discussed in another thread how the spindle harmonics affect finish. The 3 flutes create their own harmonics but at different frequencies. This difference in frequency can sometimes dampen or even cancel each other out eliminating tool marks.

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[G59]

\r\n \r\n Taking a 0.01 cut can be beneficial as a final pass, as you are biting into the material instrad of rubbing it off. A lot of it depends on the quality of the cutter.\r\n \r\n

[Steve Seebold]

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Hi Fellow Tormachers,
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\nI am making a run of these parts in 6061 aluminum and I am not really happy with my finish results so far.
\nThe non-corner rounded part is held .2" deep in a vise very snugly and the corner rounded side is held .5" deep very firmly in a vise.
\nAs you can see from the photos, there are lots of tiny vertical lines left over from the cutters.
\nHere is what I am using;
\n1) Main cutting (on vertical sides) is a Tormach 1/4" HSS E.M. in an ER20 collet at 5100 RPM and 12 IPM.
\n2) Chamfering is done with Maritool 1/4" 4-flute carbide cutter in 1/4" dia. tool holder 5100 RPM and 12 IPM.
\n3) Corner round is done with Maritool .187 radius 4-flute carbide cutter in 1/2" dia. tool holder running at 5100 RPM and 5 IPM.
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\nI originally cut the corner round at 5100 RPM and 12 IPM but it had the same line issue so I reduced the feed to 5 IPM and it is better but as you can see it still has a bunch of small vertical lines from the cutter.
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\nAny thoughts on what might be happening or how I can get a better finish? Change the speeds/Feeds?
\nIf just one of the tools was having this issue I would think it was that particular tool but all of the tools are creating these lines in surface finish.
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\nI have some Lake Shore carbide 1/4" 2-flute EM\'s coming to see if they are better but I need to stick with the MariTool profile cutters for now.
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\nThanks,
\nNathan

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You\'re just running the spindle too fast. I get a great finish on my PCNC 1100 Series II. I have experimented with feeds and seeds with my machine since I got it in July 2011. I learned that at 5100 RPM, the finish on both the walls and the floor sucks, but if I leave .015 to .025 on the floor and walls for a finish cut, use a 3/8 3 flute end mill and reduce spindle speed to 3500 RPM at 25 to 30 IPM I will get a beautiful finish.\r\n \r\n

[CadRhino]

\r\n \r\n Thanks Ray.
\r\nI will mix it up and try it.
\r\nI also have a 3/8" Tool 3/FL finishing rougher I should test as well.
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You\'re just running the spindle too fast. I get a great finish on my PCNC 1100 Series II. I have experimented with feeds and seeds with my machine since I got it in July 2011. I learned that at 5100 RPM, the finish on both the walls and the floor sucks, but if I leave .015 to .025 on the floor and walls for a finish cut, use a 3/8 3 flute end mill and reduce spindle speed to 3500 RPM at 25 to 30 IPM I will get a beautiful finish.

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[Machinehead57]

\r\n \r\n I have found that using a commercial router bit which has the 1/2" shank leaves a very nice finish on soft metals. They are extremely sharp well shaped and maintain this for a long time. One other thing never use a cutter on soft metal once used in steel, you will get the ugliest finish you ever saw. These router bit can be bought at most home supply stores in beveled corner rounding in various radius and so on.
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\r\nGood luck
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[CadRhino]

\r\n \r\n Thanks for the insight, Steve
\r\nIt makes me a little nervous using a carbide wood bit on my tormach but I will try it. Do you think it would give a better finish than the round over profile I showed?
\r\nThanks
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I have found that using a commercial router bit which has the 1/2" shank leaves a very nice finish on soft metals. They are extremely sharp well shaped and maintain this for a long time. One other thing never use a cutter on soft metal once used in steel, you will get the ugliest finish you ever saw. These router bit can be bought at most home supply stores in beveled corner rounding in various radius and so on.
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\r\nGood luck
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[300sniper]

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[mountaindew]

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Thanks for the insight, Steve
\nIt makes me a little nervous using a carbide wood bit on my tormach but I will try it. Do you think it would give a better finish than the round over profile I showed?
\nThanks

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I use 2 flute solid carbide spiral up-cut, down-cut and compression cut router bits on aluminum, plastic and wood and find in many cases they work very well. The main reason I use them is they are long and cut to depths of 1.5" or more where many standard end mills are to short for this . White side makes some of the best in my opinion and you will pay for this. At $50-$80 each they don\'t come cheap. On the other hand if used with care they will last a very long time. btw If you want the best finish possible of acrylic these are awesome and blow away most any other tool that I have ever tried.
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[Machinehead57]

\r\n \r\n The router bit with 1/2" shanks work great in a mill the 1/4" ones are to week to do much but will work if used lightly. A straight cut router bit is the best way I have found to re-spline hardened axle shafts. But yeah I think it will, do the spring cut as a final pass and use conventional milling not climb. The climb will leave little straight marks like you are getting. The extremely sharp edge of the wood bit can take the smallest of cut cleanly high spindle speed with slow travel works best. Experiment some on a piece of scrap and find the combo that works best with your setup.
\nYou would be surprised to find what can be used in a mill. I have used a fine toothed carbide tipped 7 1/4" skillsaw blades to make deep undercuts or slice off thin layers of a profiled piece.
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\nGood luck
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[CadRhino]

\r\n \r\n Thanks for the insights, Steve
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The router bit with 1/2" shanks work great in a mill the 1/4" ones are to week to do much but will work if used lightly. A straight cut router bit is the best way I have found to re-spline hardened axle shafts. But yeah I think it will, do the spring cut as a final pass and use conventional milling not climb. The climb will leave little straight marks like you are getting. The extremely sharp edge of the wood bit can take the smallest of cut cleanly high spindle speed with slow travel works best. Experiment some on a piece of scrap and find the combo that works best with your setup.
\r\nYou would be surprised to find what can be used in a mill. I have used a fine toothed carbide tipped 7 1/4" skillsaw blades to make deep undercuts or slice off thin layers of a profiled piece.
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\r\nGood luck
\r\nSteve

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[LeeWay]

\r\n \r\n I put this video in the other thread that was mentioned.
\r\nhttps://www.youtube.com/watch?v=9eyA2kq7lDM
\r\n
\r\nIt is a home made mill that has worked great for me. Finish passes should be very slow to take out some of the resonance and frequency issues. These parts off this little machine were pro quality. Almost mirror finish. The pictures do not do those parts justice. That is the result you are looking for. Something like a FINISHED part. \r\n \r\n

[pickled]

\r\n \r\n Pyramids are quick. Walnut and corn in a simple tumbler do pretty well for me when smoothing over 6061 and 7075. They will not remove scallops, but surface marks tend to drop off quite well. Yes it does take 1-2 days, but I don\'t have to worry about dimensional changes when I leave my parts in and forget about them- thankfully. They do not remove burrs and you better plug any holes that you have tapped or plan on tapping!\r\n \r\n

[CadRhino]

\r\n \r\n Ok I got my parts better by tweaking feeds speeds an using 3-flute cutters.
\r\n
\r\nNow I want to soften them a tad.
\r\n
\r\nI picked up a harbor freight 18 pound vibratory, green pyramids and some fine 24 grit walnut.
\r\n
\r\nI want to run these parts in walnut only for a day or two.
\r\nShould I run them dry or as a little soap and water to the walnut?
\r\n
\r\nI could at some point add a little jewlers rouge too.
\r\n
\r\nWhat do folks use.
\r\n
\r\nThanks
\r\nNathan
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Pyramids are quick. Walnut and corn in a simple tumbler do pretty well for me when smoothing over 6061 and 7075. They will not remove scallops, but surface marks tend to drop off quite well. Yes it does take 1-2 days, but I don\'t have to worry about dimensional changes when I leave my parts in and forget about them- thankfully. They do not remove burrs and you better plug any holes that you have tapped or plan on tapping!

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[popspipes]

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Hi Fellow Tormachers,
\r\n
\r\nI am making a run of these parts in 6061 aluminum and I am not really happy with my finish results so far.
\r\nThe non-corner rounded part is held .2" deep in a vise very snugly and the corner rounded side is held .5" deep very firmly in a vise.
\r\nAs you can see from the photos, there are lots of tiny vertical lines left over from the cutters.
\r\nHere is what I am using;
\r\n1) Main cutting (on vertical sides) is a Tormach 1/4" HSS E.M. in an ER20 collet at 5100 RPM and 12 IPM.
\r\n2) Chamfering is done with Maritool 1/4" 4-flute carbide cutter in 1/4" dia. tool holder 5100 RPM and 12 IPM.
\r\n3) Corner round is done with Maritool .187 radius 4-flute carbide cutter in 1/2" dia. tool holder running at 5100 RPM and 5 IPM.
\r\n
\r\nI originally cut the corner round at 5100 RPM and 12 IPM but it had the same line issue so I reduced the feed to 5 IPM and it is better but as you can see it still has a bunch of small vertical lines from the cutter.
\r\n
\r\nAny thoughts on what might be happening or how I can get a better finish? Change the speeds/Feeds?
\r\nIf just one of the tools was having this issue I would think it was that particular tool but all of the tools are creating these lines in surface finish.
\r\n
\r\nI have some Lake Shore carbide 1/4" 2-flute EM\'s coming to see if they are better but I need to stick with the MariTool profile cutters for now.
\r\n
\r\nThanks,
\r\nNathan

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One of my mentors told me when I was learning machining, that a smooth file was used for fine finishes, I use that a lot as well, followed with some fine emery paper etc.
\r\nMy circular cuts on the Tormach are not perfect either, the all have very short straight segments in them. There is a lot to be said for finishing in a lathe as the marks can be blended together rather easily, especially if dimensions are not super critical.
\r\n
\r\nIf the spindle and drive are not balanced really well, use an rpm that doesnt vibrate, that will make a big difference in the finish as well. Vibration transfers thru the whole machine and will be seen in the finish to some degree.
\r\nI do polish on the lathe, and it does have an adverse effect on the ways etc. Covering them with a cloth under the chuck helps with that.\r\n \r\n

[CadRhino]

\r\n \r\n Thanks for clarifying, Popspipes. I can see how the vibration things translate. Each tool run has its own unique set of sounds and sometime a weird ticking noise that seems to come from the motor (fan blades).
\r\n
\r\n Things are definitely not as simple as using Gwizard to set everything then your off.
\r\nI am going to go back and look at your posts on balancing your machine. I assume you had to take your motor housing off to access the fan to balance it.
\r\nI am still determined to find a more hands off solution but I did get my lathe fired up yesterday so I may look at that option closer if I need to.
\r\n
\r\nThanks
\r\nNathan
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One of my mentors told me when I was learning machining, that a smooth file was used for fine finishes, I use that a lot as well, followed with some fine emery paper etc.
\r\nMy circular cuts on the Tormach are not perfect either, the all have very short straight segments in them. There is a lot to be said for finishing in a lathe as the marks can be blended together rather easily, especially if dimensions are not super critical.
\r\n
\r\nIf the spindle and drive are not balanced really well, use an rpm that doesnt vibrate, that will make a big difference in the finish as well. Vibration transfers thru the whole machine and will be seen in the finish to some degree.
\r\nI do polish on the lathe, and it does have an adverse effect on the ways etc. Covering them with a cloth under the chuck helps with that.

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- - - Updated - - -
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\nThanks
\r\nI will look for one.
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Looks like typical low spindle/holder rigidity issues as well as an unbalanced condition. Have a smart phone? Download a vibration app and place it on the machine. You\'d be surprised how well something so simple can balance so well.

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[underthetire]

\r\n \r\n Looks like typical low spindle/holder rigidity issues as well as an unbalanced condition. Have a smart phone? Download a vibration app and place it on the machine. You\'d be surprised how well something so simple can balance so well.\r\n \r\n

[adamvs]

\r\n \r\n A couple of ideas that might not have been mentioned: 1) if your client can go with 7075, instead of 6061, in my experience it machines much nicer. 2) If you have time to do a little hand finishing as a second op, #000 and #0000 steel wool do wonders on aluminum - it\'s a great deburring and semi polish.\r\n \r\n

[CadRhino]

\r\n \r\n Thanks for the insight, Adam.
\r\nI will toy with some 7075 in the future but all the material I have is 6061.
\r\nIt would be cool to come up with a way to chuck up steel wool in a spindle and use that as a \'polishing\' tool.
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\r\n-Nathan
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A couple of ideas that might not have been mentioned: 1) if your client can go with 7075, instead of 6061, in my experience it machines much nicer. 2) If you have time to do a little hand finishing as a second op, #000 and #0000 steel wool do wonders on aluminum - it\'s a great deburring and semi polish.

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[CadRhino]

Hi Fellow Tormachers,

I am making a run of these parts in 6061 aluminum and I am not really happy with my finish results so far.
The non-corner rounded part is held .2" deep in a vise very snugly and the corner rounded side is held .5" deep very firmly in a vise.
As you can see from the photos, there are lots of tiny vertical lines left over from the cutters.
Here is what I am using;
1) Main cutting (on vertical sides) is a Tormach 1/4" HSS E.M. in an ER20 collet at 5100 RPM and 12 IPM.
2) Chamfering is done with Maritool 1/4" 4-flute carbide cutter in 1/4" dia. tool holder 5100 RPM and 12 IPM.
3) Corner round is done with Maritool .187 radius 4-flute carbide cutter in 1/2" dia. tool holder running at 5100 RPM and 5 IPM.

I originally cut the corner round at 5100 RPM and 12 IPM but it had the same line issue so I reduced the feed to 5 IPM and it is better but as you can see it still has a bunch of small vertical lines from the cutter.

Any thoughts on what might be happening or how I can get a better finish? Change the speeds/Feeds?
If just one of the tools was having this issue I would think it was that particular tool but all of the tools are creating these lines in surface finish.

I have some Lake Shore carbide 1/4" 2-flute EM's coming to see if they are better but I need to stick with the MariTool profile cutters for now.

Thanks,
Nathan