Bottle threads

[shifter]

Has any of you guys seen this type of callout?

 

48-400 or

48 fitment

 

These are callouts for bottle threads and I was wondering if Mastercam has the capability to allow a CNC milling machine to make the female version of this thread size. I'd like to have them machined into aluminum so that the aluminum piece would act as a cap (allow a bottle to be threaded into it).

Anyone know anything about this?

Thanks!

[JasonM]

If you have the right tool form, and the details of the thread - pitch, minor dia, etc. then you shouldn't have a problem programming it.

[shifter]

That's the problem - the only info I have is the 48-400 and 48 fitment designations. I guess I could have the inside of the cap laser-scanned, but I was hoping there'd be someone out there who had to do this, before.

 

Thanks.

[shifter]

Ah, it appears that the diameter is 48mm and the pitch is 4.00mm. I measured the male thread width to be about 2.54mm and the thread height above its base diameter is about 1.88mm. I guess it can be modeled, but..........

[JasonM]

I did a quick google search and found this.

 

http://www.plasticbottle.com/techinfo/spi.html

 

Might be applicable to you

[shifter]

That's great info - thanks, Jason! The only thing I didn't see in it is the width of each thread. If you were going to make female threads, how would you do it? Would it require a 5 axis mill? I would assume that this thread spacing cannot be done on a lathe, correct?

[SledGeek]

Lollipop type form tool on a VMC......?

[shifter]

I would think that form of mill bit is necessary, but what is a VMC?

 

Thanks

[JasonM]

Vertical Machining Center

 

I would imaging if you had the right form cutter that it would be fairly easy to cut the female thread if you had all the proper information.

[#Rekd™]

Hi Shifter,

 

This is a GPI (Glass packing institute) thread. 48 is the thread size and 400 is the finish. Go to www.gpi.org they have drawings there under tech/stats info.

 

John

[htm01]

its special thread forms,we have cutters made at a few different places,jasonm had the right site,400 means 1 turn of thread.shoot me an e-mail if you need more info.

[shifter]

Thanks, everyone. The glass packing institute web site contains a link to the cap side of things. Both sites have drawings that I should be able to use. htm01, it sounds like your shop has cut bottle threads. If so, have you cut female threads as well? I should have a drawing this weekend of a part containing female bottle threads (or cap threads, as I call them). The solid model may not be perfect, but I can always attach the pdf drawing of the threads, along with the chart. This way, I won't have to copy everything to my own drawing.

[htm01]

shifter,

yes we make plastic bottle molds,so we cut female that becomes the thread on the bottle,are you just making a part that goes on like a cap?

[shifter]

htm01,

 

Yes, I plan on using a gasket ring at the bottom of the cap. The cap will also have some pipe tap holes (2) and a center, straight threaded hole. Initially, I need just one so that I can run some experiments. I should be able to send you a drawing by Sunday night if that's okay with you. My company is as small as they come - 1 person, so I cannot spend too much. However, I'd appreciate a quote if you can - thanks!