Drilling, Tapping, Threading 303 on Light Machines

[itsme_Bernie]

Hello HM'ers

My cousin is into pen making, especially kitless pens. He recently purchased a Sherline lathe.

He wants to machine parts of his pens, which require drilling, tapping, and threading with dies. Do any of you guys have any tips for these operations in 303 Stainless?

Any suggestions for more appropriate metal for Pen making? He was using aluminum, and complaining that it was too soft and easily marred. I questioned his choice of alloy, and he was unsure.

I know 303 is pretty easily machined, and have heard that Anchorlube is a great lubricant for it. I am not sure how durable it is, in day to day use and handling as a part of a Pen.

Any pen makers out there? Any 303 aficionados?
Thanks for any thoughts and opinions here!

Bernie

 

[Terrywerm]

I have done some work with 303, nothing real special, but I had no trouble getting a nice finish on it, nor did I have any trouble with single point threading, or cutting threads with a tap or die. It was pretty nice stuff, in my thinking. Then I thought back a bit and realized that I was used to working with 316 stainless which is a bearcat. Being used to 316 it is no wonder that it was quite easy to work with 303!

 

[itsme_Bernie]

I have done some work with 303, nothing real special, but I had no trouble getting a nice finish on it, nor did I have any trouble with single point threading, or cutting threads with a tap or die. It was pretty nice stuff, in my thinking. Then I thought back a bit and realized that I was used to working with 316 stainless which is a bearcat. Being used to 316 it is no wonder that it was quite easy to work with 303!

Gotcha. To add to it, my cousin has a Sherline, so it really needs to be easy to work. I had one once, and it was wonderful. But high speed and low HP makes certain metal a challenge.

Thanks Terry!
What cutting fluid do you use, if you don't mind my asking?


Bernie

 

[mikey]

Bernie, I have a Sherline lathe and turn, drill and tap 303 a fair amount. I've not had any problems doing so, even on sizes that push the envelope for this little lathe. For turning I would recommend a HSS tool with 3-5 degrees more side rake; this will reduce cutting temps a bit more. If he doesn't dwell in the cut and uses some cutting fluid (I prefer Tapmatic Gold for 303) then he won't have any problems at all cutting 303. It finishes nicely at high speeds with light cuts.

For tapping, I suggest going with a drill one or two sizes larger than called for, particularly if the part is not load-bearing. This greatly eases tapping and I suspect it will be more than adequate for a pen.

He might also consider 7075 T-6 aluminum. It is a good bit harder than 6061 and if I'm not mistaken it might be lighter in weight. It turns very nicely with HSS but I'm not sure how it would hold up as a pen in terms of getting scratched. I've used 7075 a lot and haven't had issues with appearance - maybe I'm not too particular.

 

[itsme_Bernie]

Bernie, I have a Sherline lathe and turn, drill and tap 303 a fair amount. I've not had any problems doing so, even on sizes that push the envelope for this little lathe. For turning I would recommend a HSS tool with 3-5 degrees more side rake; this will reduce cutting temps a bit more. If he doesn't dwell in the cut and uses some cutting fluid (I prefer Tapmatic Gold for 303) then he won't have any problems at all cutting 303. It finishes nicely at high speeds with light cuts.

For tapping, I suggest going with a drill one or two sizes larger than called for, particularly if the part is not load-bearing. This greatly eases tapping and I suspect it will be more than adequate for a pen.

He might also consider 7075 T-6 aluminum. It is a good bit harder than 6061 and if I'm not mistaken it might be lighter in weight. It turns very nicely with HSS but I'm not sure how it would hold up as a pen in terms of getting scratched. I've used 7075 a lot and haven't had issues with appearance - maybe I'm not too particular.

Thanks Mikey-

I suggested 70xx series aluminum but I think he had some cheesy, gummy Al and wants to try something new. I appreciate your tips and will pass them along directly to him!


Bernie

 

[Bill C.]

Hello HM'ers

My cousin is into pen making, especially kitless pens. He recently purchased a Sherline lathe.

He wants to machine parts of his pens, which require drilling, tapping, and threading with dies. Do any of you guys have any tips for these operations in 303 Stainless?

Any suggestions for more appropriate metal for Pen making? He was using aluminum, and complaining that it was too soft and easily marred. I questioned his choice of alloy, and he was unsure.

I know 303 is pretty easily machined, and have heard that Anchorlube is a great lubricant for it. I am not sure how durable it is, in day to day use and handling as a part of a Pen.

Any pen makers out there? Any 303 aficionados?
Thanks for any thoughts and opinions here!

Bernie

I recall 303 was used in the food industry machinery. It can be buffed up to a shine with jeweler's ruse.

 

[Terrywerm]

Gotcha. To add to it, my cousin has a Sherline, so it really needs to be easy to work. I had one once, and it was wonderful. But high speed and low HP makes certain metal a challenge.

Thanks Terry!
What cutting fluid do you use, if you don't mind my asking?


Bernie

Sorry I didn't get back to you sooner, Bernie. Been out of town for a couple of days.

On stainless I usually just use plain old cutting oil, the same stuff that plumbers use in their pipe threading machines. Nothing more special than that. There might be something that works a bit better, but in my opinion, regular old stinky cutting oil works just fine.

 

[itsme_Bernie]

Thanks so much guys- good for me to know too, but I will be passing this along to my cousin too..

I heard ANCHORLUBE is great for Ss 303 too..


Bernie

 

[Terrywerm]

I forgot all about Anchorlube! It is great stuff on stainless. I have used it, but not in quite some time, thus my forgetting about it. It was one of my favorites for drilling in 316SS, but I ran out of it and never found a new source for it. Guess I didn't look very hard, they have their own website and will even send out a free 2 oz. sample. www.anchorlube.com

 

[Bill C.]

Thanks so much guys- good for me to know too, but I will be passing this along to my cousin too..

I heard ANCHORLUBE is great for Ss 303 too..


Bernie

I was thinking if your cousin not use to threading with a die to tell him/her to cut a shoulder where the threads stop. Also after die threading to turn the die around as to finish cutting the last two or three threads. Dies have a lead in taper and by turning them around completes the thread.