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What did you do Today 2018

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Mark Rand03/09/2018 11:22:32
761 forum posts
Posted by David Taylor on 03/09/2018 08:27:50:

The bench needs to come towards the camera too, the vice is barely usable now and I'm left-handed.

Being also left handed, I reasoned that all the vices in the school woodwork shop and apprentice training school were set up for right handed folk. So I put my vice at the other (right) end of the bench in my shed. Works for me smiley.

David Taylor03/09/2018 12:56:02
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128 forum posts
39 photos
Posted by Andrew Johnston on 03/09/2018 09:16:09:

Almost certainly a tool change problem. It's normal to set X, Y and Z zeros using tool 0, the master tool. When you change to tool 1, say, which is a different length the machine needs to take that into account.

I've been looking at the code from Fusion, PP conversational, and Cut2D. I think the problem is that the Cut2D post-processor turns off tool length compensation (G49), then travels to Z20.320 which the post-processor is calling the home Z position. But when there is a tool sticking 70mm out this means it will plunge 50mm into the material! Only after this does it do the G30 like the others. It makes no sense to me, even if I had an empty spindle it is just an unnecessary Z move which will be undone by the G30 so I can put the tool in.

G0 G17 G21 G90 G40 G49 G64 P0.03
G80
G0 Z20.320 <--- Waste of time?
G0 X0.000 Y0.000
G30
T8M6
(End Mill {8 mm})
G43H8

The G0s between G80 and G30 are not required - PP and Fusion don't do them.

Andrew Johnston03/09/2018 16:12:29
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4855 forum posts
544 photos

Here's a snippet of my code with tool heights taken from the table at tool change:

N10 G21
N20 G0 G80 G17 G40 G94 G54 G49 G64 G90
N30 (2 1/2 Axis Profiling - Roughing-1)
N40 M09
N50 T01 G43 H01 M06
N60 S4000 M03
N70 G04 P3
N80 G90
N90 M08
N100 G00 Z1.500
N110 X-4.000 Y-85.100
N120 G01 Z-0.800 F600.0
N130 G01 Y-82.100 F150.0

There are a few oddities in the toolchange code, such as the G90, which is there for historical reasons, must get rid of it sometime. The G04 delay is to allow the spindle to get up to speed before moving axes when machine tapping. The following is the sequence I use after powering up the Tormach:

RESET the controller using the button on the screen

Reference all active axes using the buttons - I reference Z first in case there's anything in the way. This sets the machine co-ordinates using the limit switches

Set Z=0 on the mill table using tool 0, which in my case is a length of silver steel with a ballnose end and longer than any tool I'm likely to use

If I need to fill the tool table I use the electronic tool setter and the offsets screen making sure the tool number box represents the tool I want each time

Once the work is in place I set X=0 and Y=0 on the work, or fixture, according to where I've set the origin in the CAM program

I then set Z=0, using tool 0 with 0 selected in the tool window, on the work or fixture, again according to where the CAM program origin is set

Once that is done putting tool 1 in the spindle,and selecting tool 1 in the box, should give Z=0 at the same origin as set with tool 0

It may not be the most elegant method but it works for me. When I updated to PathPilot I had a disagreement with Tormach about using tool 0. They now recommend using the spindle nose rather than a master tool. But the spindle nose is big and clumsy, and you can't see what you're doing. So I don't use it.

The post-processor is part of the CAM program rather than part of the Tormach controller. It is normal to write ones own. Which is what I did for my CAM program (VisualMill). I've got two, one using tool tables and one not. I use tool tables 95% of the time. But when I use the high speed spindle I don't want to use tables, as the spindle has no repeatable way to swap tools.

Homing for tool changes is something I must sort out. At the moment I simply edit the G-code to put in a G0 Z100.00 to move the spindle up far enough for a manual tool change.

Roll on retirement, then I'll have time to sort out all these little issues!

Andrew

mechman4803/09/2018 19:17:09
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2458 forum posts
371 photos

Yesterday actually; replaced a defunct cooker hood fan that decided to stop working last week. managed to find a 'generic' replacement on 't'internet from electrical spares provider so with the aid of a builder friend & some fiddly manoeuvring managed to swap it out. Tested out fine before replacing hood on wall so job done, in the same context has anyone done the same /similar, & would any one know if these motors are repairable as it seem a waste to throw it out if it can be repaired, the replacement aint what I would call cheap, but a lot cheaper than buying a complete new hood.

TIA

George.

Neil Wyatt03/09/2018 21:30:04
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16570 forum posts
687 photos
75 articles

I tried my first experiment with anodising today.

Just a rough-finished block that I had knocked up as a temporary telescope dovetail clamp, as it was the right size. Don't judge the workmanship!

The result was a very impressive colour, although I had to microwave the (industrial) dye to get it to work and yes it faithfully kept all the original machining marks. I can run a hardened steel screwdriver ove the finish with light pressure and it doesn't mark it, which is good.

More noticeable was where I had filled some wrongly placed holes with Alutite - they went black in the caustic soda, didn't anodise and didn't take any die. They look like JB Weld but aren't!

Tomorrow I will try a couple of 'proper' parts.

anodising test.jpg

Mark Rand03/09/2018 23:07:01
761 forum posts

I'm not sure I really want a finishing process that highlights all of my 'design changes'!

Sam Stones03/09/2018 23:50:37
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647 forum posts
254 photos

George (mechman48) ... I sent you a PM.

Regards,

Sam

Neil Wyatt04/09/2018 08:49:12
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16570 forum posts
687 photos
75 articles
Posted by Mark Rand on 03/09/2018 23:07:01:

I'm not sure I really want a finishing process that highlights all of my 'design changes'!

The block has been repurposed at least twice - that's why I had to change the placement/size of holes.

It also shows the scratched and dings unanodised alloys collect when left rattling around for a year or two.

Neil

Robin04/09/2018 09:16:07
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315 forum posts
Posted by Neil Wyatt on 03/09/2018 21:30:04:

The result was a very impressive colour, although I had to microwave the (industrial) dye to get it to work and yes it faithfully kept all the original machining marks. I can run a hardened steel screwdriver ove the finish with light pressure and it doesn't mark it, which is good.

My one attempt at anodising preserved the metal most wondrously but I could not get the colour to penetrate.

Controlling the current using an auto bulb meant it took a lot longer than expected to convert and I thought that was the problem.

Please explain this microwaving thing if you have time. I thought hot water sealed the surface.

duncan webster04/09/2018 10:18:28
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2232 forum posts
32 photos

I trust we're to look forward to an article in MEW about anodising. I'm making some bits in ally which would look a lot better black.

Edited By duncan webster on 04/09/2018 10:18:47

Neil Wyatt04/09/2018 11:12:03
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16570 forum posts
687 photos
75 articles
Posted by Robin on 04/09/2018 09:16:07:

Please explain this microwaving thing if you have time. I thought hot water sealed the surface.

It does, but the dye I'm using is optimised for 40-60C with lower temperatures giving a less intense colour.

Unlike most anodising dyes it's a chemical process based on ferric oxylate which reacts with the oxidised layer and the solution is bright green.

I'm following an industrial process which also means sealing in a cold seal solution then finishing with a simmer.

Neil

Neil Wyatt04/09/2018 11:14:03
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16570 forum posts
687 photos
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Posted by duncan webster on 04/09/2018 10:18:28:

I trust we're to look forward to an article in MEW about anodising. I'm making some bits in ally which would look a lot better black.

Edited By duncan webster on 04/09/2018 10:18:47

Yes, I'm hoping for one, but it's unlikely to be written by me.

Out of interest, that Alutite has gone 'porous' on the surface - my guess is that zinc has leached out. If scratched it shows bright silver.

Neil

mechman4804/09/2018 14:21:42
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2458 forum posts
371 photos
Posted by Sam Stones on 03/09/2018 23:50:37:

George (mechman48) ... I sent you a PM.

Regards,

Sam

Thanks, replied via pm...

Geo.

Neil Wyatt04/09/2018 14:59:18
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Moderator
16570 forum posts
687 photos
75 articles

This looks bit better. Three knobs for my telescope.

I did them together and one turned out pale (I don't think it had a very good connection with the titanium wire). It gopt close to the other two after an extra half hour in the die but I could see it wasn't ever going to match so I stripped it with caustic and reanodised it. In warm water these take about 20 -30 minutes to achieve full colour.

I'm guessing the conventional black die will take quicker.

knobs.jpg

Mick B104/09/2018 19:59:30
1187 forum posts
66 photos

Finished a nutcracker patterned after a 1950s example by Austrian modernist Carl Auböck. Not especially effective when compared to a Mole wrench but looks good:-

AubockNutcracker.jpg

...plus the truck bracket subassembly (trepanned out of flat bar) for a 68-pdr Carronade model.

CarronadeTruckBrkt.jpg

Spurry04/09/2018 20:51:30
165 forum posts
59 photos

In an attempt to try and find things when I need them, my "system" is to have various heights of 600x400 plastic trays positioned in modules with the locations shown in a database on the PC.

A requirement for a mobile module had arisen and it was completed today.

These are my original static modules made for the old workshop

img_8832a.jpg

A few shelvesimg_2933a.jpg

First side

img_2932.jpg

Assembled unit. All fitted together with just a rubber mallet.

img_2941a.jpg

Most difficult part was trying to work out how to post text and pictures. wink

Pete

Jon Lawes04/09/2018 20:54:49
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325 forum posts

Neil those telescope knobs look superb!

I reprofiled the Britannia wheels to give them the 3 degree profile recommended, and made more of the bogie. Very satisfying.

Neil Wyatt04/09/2018 21:39:20
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16570 forum posts
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Very nice Mick.

Neil

Mick B104/09/2018 22:08:16
1187 forum posts
66 photos
Posted by Neil Wyatt on 04/09/2018 21:39:20:

Very nice Mick.

Neil

Well, thank you but they seem very limited things compared with some of the stuff you and others do. You seem to've put in a temp/humidity gauge with one of your control knobs - I take it that's to help control dew condensation on your mirrors or lenses?

Neil Wyatt04/09/2018 22:29:49
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16570 forum posts
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75 articles
Posted by Mick B1 on 04/09/2018 22:08:16:
You seem to've put in a temp/humidity gauge with one of your control knobs - I take it that's to help control dew condensation on your mirrors or lenses?

Nowt wrong with your work at all!

Williams Optics (makers of posh telescopes) put a thermometer on the one-speed knob of some of their scopes. Personally I think humidity would be more useful. I googled for a round humidity meter and I found these cheap clip-in units for next to nothing.

Neil

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