[Bob La Londe[_7_]]

I need to machine some metric trapezoidal threads. Both internal and
external.

What's the best way to do that?

Is hand grinding the tools going to be my best approach? I think maybe it
is since they are for making molds of two mating parts. The molds can't be
of the exact thread forms or the parts won't fit together. A proper cutting
tool for those threads might not produce what I need. I'm still thinking my
way through the process.

[shiggins]

On 12/5/2018 10:04 AM, Bob La Londe wrote:
I need to machine some metric trapezoidal threads.Â* Both internal and
external.

What's the best way to do that?

Is hand grinding the tools going to be my best approach?Â* I think maybe
it is since they are for making molds of two mating parts.Â* The molds
can't be of the exact thread forms or the parts won't fit together.Â* A
proper cutting tool for those threads might not produce what I need.
I'm still thinking my way through the process.



There's guy on Youtube that ground his own tools for making ACME
threads. Same thing as trapezoidal. Only different.
He has a channel.
This Old Tony.

Steve

[Bob La Londe[_7_]]

"shiggins" wrote in message
...

On 12/5/2018 10:04 AM, Bob La Londe wrote:
I need to machine some metric trapezoidal threads. Both internal and
external.

What's the best way to do that?

Is hand grinding the tools going to be my best approach? I think maybe it
is since they are for making molds of two mating parts. The molds can't
be of the exact thread forms or the parts won't fit together. A proper
cutting tool for those threads might not produce what I need. I'm still
thinking my way through the process.



There's guy on Youtube that ground his own tools for making ACME
threads. Same thing as trapezoidal. Only different.
He has a channel.
This Old Tony.

Steve


****************
Thanks Steve. I actually follow his channel and I've seen the "ACME?
Ac-You" title a few times. I don't think I ever watched it before. Thanks
again.

[Jim Wilkins[_2_]]

"Bob La Londe" wrote in message
news
I need to machine some metric trapezoidal threads. Both internal and
external.

What's the best way to do that?

Is hand grinding the tools going to be my best approach? I think
maybe it is since they are for making molds of two mating parts.
The molds can't be of the exact thread forms or the parts won't fit
together. A proper cutting tool for those threads might not produce
what I need. I'm still thinking my way through the process.

A local vendor who has closed sold me an imported 3-axis angle vise
like this that I use to surface-grind angular and trapezoidal
threading and spline milling bits.

http://www.wikiwand.com/en/Tool_and_cutter_grinder

[Bob La Londe[_7_]]

"Jim Wilkins" wrote in message news
"Bob La Londe" wrote in message
news
I need to machine some metric trapezoidal threads. Both internal and
external.

What's the best way to do that?

Is hand grinding the tools going to be my best approach? I think maybe it
is since they are for making molds of two mating parts. The molds can't be
of the exact thread forms or the parts won't fit together. A proper
cutting tool for those threads might not produce what I need. I'm still
thinking my way through the process.

A local vendor who has closed sold me an imported 3-axis angle vise
like this that I use to surface-grind angular and trapezoidal
threading and spline milling bits.

http://www.wikiwand.com/en/Tool_and_cutter_grinder

*****************

The link brings up a CNC tool grinder. If that's what he gave you.... WOW!
I'm impressed.

You reminded my I have an antique (its so old the cords have cloth wrap)
basic tool grinder on the shelf that I saved from going into the dumpster on
a house clean out from a hoarder who passed on. Its halfway apart and
needs to be taken all the way apart, but it might just be a good project to
move up the projects board.

[Jim Wilkins[_2_]]

"Bob La Londe" wrote in message
news
"Jim Wilkins" wrote in message news
"Bob La Londe" wrote in message
news
I need to machine some metric trapezoidal threads. Both internal
and external.

What's the best way to do that?

Is hand grinding the tools going to be my best approach? I think
maybe it is since they are for making molds of two mating parts.
The molds can't be of the exact thread forms or the parts won't fit
together. A proper cutting tool for those threads might not
produce what I need. I'm still thinking my way through the
process.

A local vendor who has closed sold me an imported 3-axis angle vise
like this that I use to surface-grind angular and trapezoidal
threading and spline milling bits.

http://www.wikiwand.com/en/Tool_and_cutter_grinder

*****************

The link brings up a CNC tool grinder. If that's what he gave
you.... WOW! I'm impressed.

You reminded my I have an antique (its so old the cords have cloth
wrap) basic tool grinder on the shelf that I saved from going into
the dumpster on a house clean out from a hoarder who passed on.
Its halfway apart and needs to be taken all the way apart, but it
might just be a good project to move up the projects board.

I wish! My surface and cutter grinder is a small manual machine from
the 1940's.

The vise is similar to the vise on multiple swivels on the table of
the green manual tool & cutter grinder. I used it for example to grind
a trapezoidal bit to spline a shaft to accept a motorcycle final drive
sprocket, in the transmission on my sawmill.

I machined the shaft grooves slightly too small and pressed on the
sprocket, so the bit geometry didn't have to match exactly.