| |
| |||||||
 |
| | LinkBack | Thread Tools | Display Modes |
10-02-2006, 06:19 PM
| #1 |
| owner, Holmes Hobbies LLC   Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
|  Unknown metal, wont lathe with HSS I have some "shaft" that I am turning down. The HSS bits I am sharpening just turn into mush against the material. It looks like a chromed shaft, but I think it is just a shiny steel. Maybe a high nickel content? Any tips on ID'ing the material or getting a cut going? Heat it till to change the temper? Get some carbide cutters? I have browsed the manufacturing forum for quite a while now and cant seem to find the answers I look for. |
|  |
| Sponsored Links | |
| | |
|
10-02-2006, 06:29 PM
| #2 |
| I'm a stupid C U N T!  Join Date: Jun 2005 Location: In the Garage!
Posts: 4,361
| Are you getting the bits excessively hot while sharpining them? that can make them soft. also you may want to adjust your rpm's abit? I only have limited Exp. on a lathe but ive learned a few things the hard way.  |
|
| |
|
10-02-2006, 06:48 PM
| #3 |
| I wanna be Dave Join Date: Jul 2005 Location: Cedar Rapids
Posts: 2,031
| I had the same problem clearancing a cross pin in a 1:1 diff. Went through several bits instantly. I figgured it was just the hard chrome like coating. I was right, ground through it with the 4". Then it was smooth saling with the machining. |
|
| |
|
10-02-2006, 07:36 PM
| #4 |
| Pebble Pounder Join Date: Aug 2005 Location: Rochester
Posts: 121
| I'd switch to carbide... after using it once, I'll never go back- just seems to make life so much easier. |
|
| |
|
10-02-2006, 07:48 PM
| #5 | |
| 2006 2.2 National Champ  Join Date: Dec 2004 Location: Driving my R/C rototiller
Posts: 7,941
| Quote:
Sometimes carbide won't do it either. If that's the case, a grinder is the only way. As mentioned already, plating and heat treating can make metal extremely hard on the outside. Sometimes if you take a deep enough cut you can get into the softer material underneath. It might be possible to get it annealed (sp.), but you'd have to know exactly what kind of metal the shaft is made of. What diameter shaft is it? How sharp is the H.S. bit? How many RPM's you turning? | |
|
| |
|
10-03-2006, 10:25 AM
| #6 |
| Pebble Pounder Join Date: Jan 2005 Location: st. louis
Posts: 113
| if its a shaft that is normaly used for linear roller bearings then the shaft is hardened ground and polished, they can also be chromed. either way its going to be in the 60-65RC in hardness. you will need carbide tools to get anywere with it. |
|
| |
|
10-03-2006, 11:51 AM
| #7 |
| owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
| rpms, dont know. Tried it on high and low. I have an old logan lathe and it doesnt say the rpms of the different gears. bits- as sharp as I can get em on my fine grinding wheel. Sharp enough to slice a finger easily. As soon as they touch the metal the cutting edge is literally deforming. 5mm shaft I am turning down to 3.17mm I took it to the grinder, the metal is of consistant hardness and material. It looks like chrome all the way through. When it hits the grinder, the metal almost tears away. It doesnt leave a good finish at all on the grinder either. I am going to try hardening the HSS bits once, and I am ordering up some carbide bits today. Seems like the only option at this point. |
|
| |
|
10-16-2006, 04:39 PM
| #8 |
| owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
| Finally got this ****e turned down! It was a combination of tool overhang, work deflection, and improper tool material. These little shafts are flexy, and any more than 1cm of work overhang makes the tool chatter like morse code. Still hard to get a consistant diameter, but I am going to try turning the shaft down in two sections or three instead of one. It should "fix" my problems. The Carbide still gets mucked up though. I cant afford one bit per shaft! |
|
| |
|
10-16-2006, 05:09 PM
| #9 | |
| I wanna be Dave   Join Date: Apr 2004 Location: SoCal
Posts: 4,212
| Quote:
 | |
|
| |
|
10-16-2006, 05:11 PM
| #10 |
| owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
| got one, I used it to grind the flat spot for the pinion  |
|
| |
|
10-18-2006, 12:29 PM
| #11 |
| owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
| Just an update. As I machine the ferrous metal more and more, each cut seems to be cutting smoother. I have found that burying .010" of the bit into the metal and feeding the handcrank fast is the best bet for a smooth and quiet cut. Letting the bit sit in one spot work hardens the shaft and blunts the cutting edge very fast! |
|
| |
|
10-18-2006, 08:13 PM
| #12 |
| TEAM MODERATOR  Join Date: May 2004 Location: Tennessee
Posts: 10,770
| When my buddy turned down the shaft in my MPJet motor,it dulled the bit fast also. He tried different speeds and different cutters as well. He said it worked as well and just as fast putting a small file in the tool rest and slowly filing it down. Don't know if it'll help,just tossin out ideas. |
|
| |
|
10-18-2006, 08:45 PM
| #13 | |
| 2006 2.2 National Champ Join Date: Dec 2004 Location: Driving my R/C rototiller
Posts: 7,941
| Quote:
| |
|
| |
|
10-18-2006, 11:34 PM
| #14 |
| owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
| The hardness actually seems consistant all the way through the shaft. What I meant to say is "my lack of skill made the first cuts horrible, and each cut thereafter gets marginally better as I learn". |
|
| |
|
10-19-2006, 08:46 AM
| #15 |
| Web Wheeling   Join Date: Jan 2005 Location: Twin Cities
Posts: 2,837
| Does this mean that we will soon hear how this new motor works? |
|
| |
|
10-19-2006, 12:32 PM
| #16 |
| owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
| |
|
| |
|
10-19-2006, 12:39 PM
| #17 |
| Web Wheeling Join Date: Jan 2005 Location: Twin Cities
Posts: 2,837
| Yup... Didn't think to look in the motors forum for it before. Kept checking the vendors forum for updates on this :-P |
|
| |
|
10-19-2006, 12:48 PM
| #18 |
| owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
| Before I post up the vendor thread, I want to make sure everything goes smooth and all the details are worked out. Should be a few more business days, probably mid next week. |
|
| |
|
11-08-2006, 03:01 PM
| #19 |
| owner, Holmes Hobbies LLC Join Date: Nov 2004 Location: Volt up! Gear down!
Posts: 14,854
| One more update on this. Today I tried heating the shaft until cherry red and then letting it air cool. WOW! It machined so smooth, the finish is awesome, and my bits are lasting much longer now. So, my assumption is that these are hardened steel shafts. They do cut as-is, but changing the temper really helped! |
|
| |
|
11-18-2006, 05:00 PM
| #20 |
| Newbie Join Date: Apr 2006 Location: Canby
Posts: 13
| So what you did is you anealed the metal. Which makes it softer. Be carful when using the rod after you are done anealing it because it will not be even close to as stong as it was before it was anealed. |
|
| |
|
| Thread Tools | |
| Display Modes | |
| |
Linear Mode
