Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: hoges on October 29, 2012, 05:05:56 PM

Title: Copying the lock cutouts on an old shotgun.
Post by: hoges on October 29, 2012, 05:05:56 PM

Hi all, I have spent a lifetime in engineering and will be retiring next year, Phew!

I have no experience of CNC software or machines but plenty on manual metal cutting machines.

I plan to spend my retirement restoring old shotguns many of which need restocking at up £2000 a go so not practicable as it is a lot more than they are worth. 

How sensible is it to try and programme a machine to cut out the lock end of a gun? and what kit do I need to do it?


Hoges,

Title: Re: Copying the lock cutouts on an old shotgun.
Post by: Hood on October 29, 2012, 06:30:09 PM

You would really need to describe more what you are wanting to do or maybe even pictures would help?
Hood

Title: Re: Copying the lock cutouts on an old shotgun.
Post by: BR549 on October 29, 2012, 07:17:05 PM

A small bench top size cnc mill with a small 4th axis would do all you need to do.  The lock plates are not very big. Th 4th is handy for cutting square ends on shafts and cutting the sear notches perfectly in time.

Just a thought, (;-) TP

Title: Re: Copying the lock cutouts on an old shotgun.
Post by: BR549 on October 29, 2012, 09:24:16 PM

I guess I read that wrong. You want to cut the pockets where the locks locate.  That would take a small router.

(;-)TP

Title: Re: Copying the lock cutouts on an old shotgun.
Post by: hoges on November 01, 2012, 02:35:27 PM

Hi BR549,

what I am trying to get a feel for is if it is possible to cut out the recess in the gun stock to fit the lock and the action in a new piece of wood using Mach and a 3 axis machine.

I tried to post a picture last night but no joy ?

Hoges

Title: Re: Copying the lock cutouts on an old shotgun.
Post by: BR549 on November 01, 2012, 04:17:37 PM

Yes it would be easy to do. You have to learn to create the pocket  gcode  correctly and then learn to locate that pocket on the stock properly.

Then learn to create a fixture to hold it securely at the proper orientation.

Not overly hard but there is a learning curve to the full process.

NOW what you need to know is that it cannot cut a square inside sharp corner. So there MAY be some hand fitting involved for the finished product.

(;-) TP

Title: Re: Copying the lock cutouts on an old shotgun.
Post by: RICH on November 01, 2012, 05:05:03 PM

Quote

How sensible is it to try and program a machine to cut out the lock end of a gun? and what kit do I need to do it?

It would be easy to do as compared to doing it by hand. There will be some hand work but minor.
If I were to do it i would just make a drawing of the pockets required and use a program to generate the code for the pockets.I say pockets because because there may be more than one.

There are a couple of options. You use CAD to create a dxf file, import it to a program such as LazyCam, Cambam,cut2d,
etc and generate the code for the machining  for use by Mach.

Another way would be to use Copycat which uses a webcam to trace the lines of the lock. and while doing that you assign the cut depth and Copycat generates the code on the fly.

There are other ways but the above give you some options to explore.

So you have some learning to do.

Have fun,

RICH

Title: Re: Copying the lock cutouts on an old shotgun.
Post by: hoges on November 01, 2012, 05:38:13 PM

Thanks for all the info.

Never one to resist a chalange here I go again!  I guess best not to stsrt with a £500 piece of Walnut.

Thanks again

Hoges.

Title: Re: Copying the lock cutouts on an old shotgun.
Post by: BR549 on November 01, 2012, 06:02:11 PM

Yep normally there are 2 pockets the first shallow one that the plate locates and rest against, then the second relief pocket to clear the lock mechanism.

(;-) TP