Author Topic: Going over to the dark (CNC) side!  (Read 10377 times)

Offline Jasonb

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Re: Going over to the dark (CNC) side!
« Reply #45 on: March 04, 2019, 01:03:31 PM »

I'd have tackled the engine pillars in a slightly different way. I'd have done a helix all the way through in the centre and then incremented out, leaving about 0.5mm of stock. Then I'd have done a profile pass full depth to finish using a circular approach and retract. That way you avoid possible tool marks from multiple passes, and minimise tool deflection. I'd then take out the recess in one pass. For the outer profile I'd probably do it in two depth passes, again leaving about 0.5mm stock. Followed by a full depth profiling pass. I'd probably leave the tabs, but experience shows they're a PITA to remove without impairing the visual appearance of the part. At least I'd try and put them in places that mate with other parts so they're not seen.

Andrew

Thanks Andrew, that make sense as you get to use all of the cutter and as you say no risk of the various passes showing down the edges. I've done that with Cut2D and it does not make much difference to the suggested time though I did do the outer profile in 4 rather than two. May give it a run if I can find another bit of scrap Ali.

Online Vixen

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Re: Going over to the dark (CNC) side!
« Reply #46 on: March 04, 2019, 01:37:56 PM »
My PathPilot screen has 1mm as the maximum jog.  I also set jog feed rate to 40% of rapid.

That's useful to know. I contacted Tormach about the issue and they promised to change the values. I'm still using an early version of PathPilot, so it may be that Tormach did indeed update the values in a later release.

Andrew

PathPilot is derived from LinuxCNC.

With LinuxCNC, the jog increments are defined in the . INI file.

Go to the machines . INI file, in the [DISLAY] section you will find the INCREMENTS parameters listed. You can change and save the INCREMENTS parameters

I do not know if this works for Pathpilot as well as LinuxCNC. It is worth a try, you can always return to the original setup. :zap:

Mike

« Last Edit: March 04, 2019, 01:52:55 PM by Vixen »
It is the journey that matters, not the destination

Offline jadge

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Re: Going over to the dark (CNC) side!
« Reply #47 on: March 04, 2019, 03:57:38 PM »
I do not know if this works for Pathpilot as well as LinuxCNC. It is worth a try, you can always return to the original setup. :zap:

Me + fiddling with computer software internals =  disaster

Company IT managers have been known to turn white when I appear at their desk.  ::)

It's pretty windy here today, so I haven't gone out to the gliding club to rig my glider and measure the control deflections. Instead this afternoon I have updated my PathPilot to Tormach version 1.9.13 and lo and behold the metric jog steps have changed to slightly more sensible numbers. PathPilot is now on version 2.x, but to upgrade to V2 I need to buy a USB stick. Which will probably cost more to ship to the UK than the cost of the stick.  :(

Andrew

Offline kvom

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Re: Going over to the dark (CNC) side!
« Reply #48 on: March 04, 2019, 04:18:14 PM »
A good practice is to place tabs on straight surfaces rather than curves.  Easier to clean up.  They don't need to be as large as yours.

For your engine parts, a no-tab solution would be to use stock thicker than needed.  The outer profile would then be milled so that it doesn't cut through.  Then fill the slot with an epoxy gel, wait for it to harden, and then face mill the back side to reveal the part.  The place in boiling water to release the epoxy.

Instead of epoxy, cut a pocket in some soft jaws that matches the output profile.  Then you can hold it securely when removing the bottom layer.  This is a good solution when making a lot of copies.

Offline kvom

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Re: Going over to the dark (CNC) side!
« Reply #49 on: March 04, 2019, 04:25:03 PM »
@jadge

I'm running the 1.9 version myself on non-Tormach equipment and see no reason to update.  The CD version costs $100, and I doubt the USB stick would be more.

Notice that typing G20 in MDI will change the jog steps and DRO values to imperial; G21 back again.  Even when machining a metric part, I will often switch to imperial since I'm using an edge finder with a .200" diameter.

Offline Jasonb

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Re: Going over to the dark (CNC) side!
« Reply #50 on: March 04, 2019, 05:02:41 PM »
This is the Cut2D version with the paths suggested by Andrew.

I have used smaller tabs but put them on surfaces that are not going to mate with others - the flat bottom and concave top therefor have clean machined mating faces. As I said the rest will get the corners knocked off with a dremel and files to get a better "cast" look and then be painted so my thinking is better to have the tabs there in this instance.

« Last Edit: March 04, 2019, 05:17:32 PM by Jasonb »

Offline jadge

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Re: Going over to the dark (CNC) side!
« Reply #51 on: March 05, 2019, 08:42:55 AM »
I'm running the 1.9 version myself on non-Tormach equipment and see no reason to update.  The CD version costs $100, and I doubt the USB stick would be more.

The USB stick for V2.x is $24.95; I've ordered one. Unexpectly the order went through with 'free' postage. Not sure I believe that! I had some trouble updating my profile (clunky website software) but it should be clear I'm outside the US. We'll have to wait and see what happens.

Andrew

Offline gary.a.ayres

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Re: Going over to the dark (CNC) side!
« Reply #52 on: March 06, 2019, 12:27:05 PM »
Jason -

the potential of this is huge.

Enjoy!

Offline DICKEYBIRD

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Re: Going over to the dark (CNC) side!
« Reply #53 on: March 06, 2019, 08:33:10 PM »
@jadge00

 Even when machining a metric part, I will often switch to imperial since I'm using an edge finder with a .200" diameter.
After screwing up a part or 2 doing the edge finder switch-eroo, I recently started touching off my .200" E/F @ 2.54 mm.  Works great & no more miscues!
"Accuracy is the sum total of your compensating mistakes."

"The thing I hate about an argument is that it always interrupts a discussion." G. K. Chesterton

Offline kvom

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Re: Going over to the dark (CNC) side!
« Reply #54 on: March 06, 2019, 09:17:04 PM »
@jadge00

 Even when machining a metric part, I will often switch to imperial since I'm using an edge finder with a .200" diameter.
After screwing up a part or 2 doing the edge finder switch-eroo, I recently started touching off my .200" E/F @ 2.54 mm.  Works great & no more miscues!

One reason I do it the other way is when my stock isn't metric and I'm center finding using opposing sides, seeing the DRO at expected dimension + .2" gives a degree of confidence that I didn't screw it up.  Note that until the current engine build I'd never machined any metric parts, so habits are hard to break.

Offline jadge

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Re: Going over to the dark (CNC) side!
« Reply #55 on: March 06, 2019, 09:54:12 PM »
I use a Haimer Zero Master to pick up edges. Using one means you don't need to worry about imperial or metric units, simply jog until the needle is on zero.

Andrew

Offline kvom

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Re: Going over to the dark (CNC) side!
« Reply #56 on: March 06, 2019, 11:58:00 PM »
I use a Haimer Zero Master to pick up edges. Using one means you don't need to worry about imperial or metric units, simply jog until the needle is on zero.

Andrew

I recently bought a Haimer Taster.  The problem I've had with it is that I don't have a pendant and use the keyboard to job.  Accidentally hitting an arrow key instead of PgUp has resulted in destroying 2 of the probes at a cost of $50 each time.  So now it's confined to the Bridgeport.   >:(

Online Vixen

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Re: Going over to the dark (CNC) side!
« Reply #57 on: March 07, 2019, 12:32:58 PM »
For edge finding, centre finding and other work, I use a 3 axis touch probe and the LinuxCNC Probe Screen utility



The probe is permanently mounted on a quick change toolholder and has a replaceable Haimer stylus.

The LinuxCNC Probe Screen utility will automatically find an inside or outside edge, corner, hole centre or bar centre at the touch of a button. The probe makes some beautifully choreographed moves to find the required edge or corner or centre, then moves to the clearance height resetting the appropriate X or Y coordinates to zero.

I crashed one of those expensive Haimer stylus tips while initially setting the search parameters. After that, I set the search speed fairly low ( 10 and 2 inches per minute) to be within human reaction times rather than having it whizzing about at the speed of light. The lower search speeds only add about 10 to 15 seconds to each operation, but is much safer.

I am very pleased with the touch probe and the  LinuxCNC Probe Screen utility. It works for me.

Mike
« Last Edit: March 07, 2019, 04:38:40 PM by Vixen »
It is the journey that matters, not the destination

Offline jadge

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Re: Going over to the dark (CNC) side!
« Reply #58 on: March 07, 2019, 12:35:43 PM »

Accidentally hitting an arrow key instead of PgUp has resulted in destroying 2 of the probes at a cost of $50 each time.  So now it's confined to the Bridgeport.   >:(

I feel your pain. At the end of last year I broke the probe on my Zero Master. I managed to break mine on the Bridgeport by turning the handle the wrong way while in a rush to finish a job for work. :'(

Andrew

Online Vixen

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Re: Going over to the dark (CNC) side!
« Reply #59 on: March 07, 2019, 01:18:21 PM »
Here is the tutorial, installation and user guide for the LinuxCNC Probe Screen utility.

https://vers.by/en/blog/useful-articles/probe-screen

If you are a LinuxCNC user, you will find this a very useful tool. It may also work with Pathpilot, but I have not tried that yet.

Mike
It is the journey that matters, not the destination