Form tools on the lathe

[Shawn]

I was watching Toms video last night about using a corner rounding endmill to cut a radius in the lathe and had to give it a try today. I had a 1/4" thick piece of O1 tool steel in the shop so I cut a couple short pieces. I used a 10 degree angle to place the piece in my mill vice and used a 3/8th endmill to plunge cut a radius. I know it won't be a perfect circle due to the angle at which I held the work but I couldn't think of a better way to get the clearance angle I needed. Then it was just a matter of grinding the tool to provide clearance angles on the front and side edges, heat treat and an hour in the toaster oven at 400 degrees to temper. I cleaned up the edges with a diamond hone and tried cutting a ball in aluminum bar. Took a bit of fine tuning on the grinder but I can see making a number of these form tools for adding some detail to handles etc. 
















The pics didn't come out in order but it's easy enough to get the idea. I have one more tool in the oven right now and will post a few close up photos soon. 

Shawn

[Shawn]

Here's a better shot of the first tool, I was spinning the lathe in its lowest gear (direct drive) and didn't get any chatter but the work did want to ride up on the tool if I plunged to aggressively. I will try it in back gear and see if that helps any. 

[Shawn]

Had a  go on some 12L14 and it cut no problem. If I had of been thinking I would have cut a profile in both ends of the form tools!

[DaveH]

Very nice work  
 
DaveH

[Shawn]

Thanks Dave, simple idea but I think it opens up a lot of possibilities for adding that finishing touch to a project. 

On a slightly different topic, when I heat treated the tools I went a little hotter than what is shown in the photo. I used a handheld Mapp gas torch and concentrated the heat more on the cutting edge, wasn't able to hear the full part evenly. Would the colour in the photo be considered carrot orange? Cherry red would be quite a bit redder I assume?

Shawn

[dallen]

stick a magnet to it when it won't stick your at temperature for most metals that will harden.

Use a second brick as a wall to bounce the heat off of back onto the part your heating.

DA

[DaveH]

Cherry red, I've always had a problem with cherry red mainly because I have seen so many different red coloured cherries  

I like bright red  

One of the troubles with seeing colours we all see them differently another problem is not being able to judge the colour subjectively.
It is far better for our eyes to judge colours by comparing hence the term 'cherry red'

As the temperature goes up it goes from red, to bright red, to orange/red (carrot). So orange/red (carrot) is hotter than bright red.

What was the question ................  My rubbish guess is the colour in your photo is red next (going up in temperature) should be bright red then orange red (carrot).

Bit of a rubbishy answer

 
DaveH

[Shawn]

Thanks Dallen, I have meant to buy a second brick and will do so tomorrow. I should have remembered the magnet trick as well, will give that a go on the next ones. I have a cherry tree in my front yard and have never seen metal turn what I see as cherry red so your right Dave, it's all subjective. I'll keep experimenting and learning, it's half the fun anyways.

Cheers
Shawn

[DaveH]

(01-28-2015, 07:55 PM)Shawn Wrote: I'll keep experimenting and learning, it's half the fun anyways.

Cheers
Shawn

100%

DaveH

[Highpower]

(01-28-2015, 07:50 PM)DaveH Wrote: One of the troubles with seeing colours we all see them differently another problem is not being able to judge the colour subjectively.
It is far better for our eyes to judge colours by comparing hence the term 'cherry red'


 
DaveH

+1

I cheat and resort to using my box of crayons.