What did you do Today 2018

[Michael GilliganParticipant @michaelgilligan61133]

Posted by SillyOldDuffer on 21/08/2018 08:52:58:

My experience of superglue used to hold work is that it works well about 80% of the time and I'm not sure what causes the failures. I wonder if the bond gets too hot?

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I suspect that the main problem is that [most, cyanoacrylate] 'superglue' is brittle, rather than tough.

I haven't researched the market for near 30 years, but 'the way forward' with egineering adhesives was then 'toughened acrylic'.

MichaelG.

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Edit: an alternative, for special jobs, might be this:

http://www.lakeside-products.com/html/cement.html

The No 70C product is very effective … but priced accordingly !

Edited By Michael Gilligan on 21/08/2018 09:28:50

[David TaylorParticipant @davidtaylor63402]

I wonder if 5 minute epoxy might work better? Superglue does seem to be really strong in some circumstances and useless in others.

Has anyone tried double-sided tape? I can't find any that isn't thick and spongy so probably not what I'm looking for.

[Michael GilliganParticipant @michaelgilligan61133]

PostScript

Anyone who has stopped 'crack propogation' in [say] a motorcyle windscreen, by drilling a small hole, should recognise the inherent logic in toughening adhesives:

**LINK**

UCD Participation at the Adhesion Society Annual Meeting

MichaelG.

[RobinParticipant @robin]

How about good ol' shellac? You paint it on as button polish, thick as you like to both surfaces, dry it, fuse them together at around 80degC, cut your part then melt again to get it apart.

[Tony JeffreeParticipant @tonyjeffree56510]

I've used superglue and also double sided sticky tape for work holding before now – both suffer the problem that the adhesion reduces as the part warms up, so they have to be used with care. Epoxy also softens with heat, so would suffer the same problem.

An alternative workholding adhesive often used in clock/watchmaking is shellac, but again, it softens with heat.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Robin on 21/08/2018 10:31:18:

How about good ol' shellac?

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Nothing much wrong with Shellac

… but it, too, may be a little brittle for some jobs.

MichaelG.

[DrDaveParticipant @drdave]

I am tarting up the control box for my lathe. Instead of bodging something from a bit of of-the-shelf steel from Wickes, I ordered some bespoke sheets to be cut to size for me. They have just arrived so I am feeling smug.

Or I was until I realised that I have no excuse not to finish the job now. Hump!

[Anonymous]

David: Thanks for the notes. I'm going to be using 16swg, about 1.5mm, CZ120 engraving brass for my nameplate. I'd thought about double sided tape, but I suspect it won't like the coolant. I plan to make a small fixture, like an inverted T-nut, to go in the machine vice and screw down to that through some sacrificial parts of the brass square.

Andrew

[Ron LadenParticipant @ronladen17547]

Posted by David Taylor on 21/08/2018 09:50:06:

Has anyone tried double-sided tape? I can't find any that isn't thick and spongy so probably not what I'm looking for.

David, If you are looking for thin/non spongy double sided tape go to a carpet shop/supplier, thats where I have always got mine. Its usually 50mm wide, thin and as sticky as hell, well at least the roll I have is.

Ron

 

Edited By Ron Laden on 21/08/2018 15:56:30

Edited By Ron Laden on 21/08/2018 15:59:05

[Neil WyattModerator @neilwyatt]

Posted by Andrew Johnston on 20/08/2018 21:48:41:

The complete assembly or just the nameplate ring? The whole assembly is fine, but what you can't see is that there is 3/4" boss underneath that locates in the smokebox door. For 3D printing I'd hide that otherwise most of the boss will be unsupported. Confirm what you'd like and I'll ping the STL file by email.

Andrew

Thanks Andrew,

Just the ring/boss as shown in your picture, but if the underside is uneven, don't worry I can chop that off in Cura by 'sinking' it into the bed.

Neil

[Neil WyattModerator @neilwyatt]

I find copper doesn't like superglue, I don't think it adheres well to any surface tarnish, so adding a bright surface texture with fine emery might be a solution.

Neil

[chris stephensParticipant @chrisstephens63393]

What did I do today? Well by my estimation I took a couple years of my life by boring and sleeving the oil pump housing on a BMW boxer crankcase. Close tolerance work leads to nerve racking and palpitations, hence life shortening, it pays well but is really worth it?

I can see why some folk take to drink, even though I have done it before and should have learned by now, guess that makes me an old dog.Ho hum!

[Michael GilliganParticipant @michaelgilligan61133]

Today … found an unexpected source of useful-looking metal stock.

If you are in the vicinity of Dagfields [near Nantwich, Cheshire] … look at Unit 211 in Building 6

**LINK** http://www.dagfields.co.uk/

He has a small but very tasty selection of non-ferrous materials; including bronze bar, and copper tube in model-boiler-making sizes.

It's the usual arrangement of 'Antiques Centre' with a single checkout for absentee sellers, but the folks on the checkout generally have telephone contact with the sellers.

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Andrew Johnston on 21/08/2018 15:13:27:

… I'd thought about double sided tape, but I suspect it won't like the coolant.

.

That's one advantage of the Lakeside 70C 'cement' that I mentioned.

… Unfortunately I have no idea what it 'really is' by any other name.

MichaelG

[Ian PParticipant @ianp]

Posted by Andrew Johnston on 21/08/2018 15:13:27:

David: Thanks for the notes. I'm going to be using 16swg, about 1.5mm, CZ120 engraving brass for my nameplate. I'd thought about double sided tape, but I suspect it won't like the coolant. I plan to make a small fixture, like an inverted T-nut, to go in the machine vice and screw down to that through some sacrificial parts of the brass square.

Andrew

I think I would use carpet tape to fix the brass to a dead flat but larger metal plate and prevent the coolant getting to the tape run a small bead of sealant round the edge. Dead flat only matter if you are using a tapered cutter and are concerned about the line width. If coolant did get to the edge of the adhesive I think it would only be a problem if it made the adhesive swell and bend the plate.

I find the biggest problem unsticking the part after machining. Easy if you can use heat, but if you have to pry the two apart its easy to bend something. One never know until afterwards but often parts can be held in place with small pads of tape rather than covering the whole surface, and that would make separating much easier.

Ian P

[MuzzerParticipant @muzzer]

I don't think it's generally understood why the paper tape / superglue trick works so well.

Check out a couple of examples:

Coolant and decent MMR

The long story

It gives a connection that's clearly very solid in operation yet allows the bond to be broken once the job is done. The tape tears once a fracture has been started – I think that's what marks it apart from solid superglue or shellac etc. Hopefully somebody with a strong armchair instinct could explain the mechanism.

Given the context of this thread, I should explain that I am (again) deprived of workshop access for the time being. Luckily I'm the devil's own cook, so concocted a load of cottage pie and generic mince for the freezer. It's not quite as fulfilling as generating swarf but will avoid me wasting away.

Murray

[Tony JeffreeParticipant @tonyjeffree56510]

Hmmmm…the Tormach video left me wondering why they used 2 layers of masking tape stuck together with super glue rather than double sided tape. Way back in my teens, I remember turning bowls on a wood lathe by using a plywood backplate with a sheet of watercolor paper sandwiched between the wooden blank and the backplate, held together with wood glue. After turning the bowl, you split the bowl from the backplate by splitting the paper with a chisel. You could do exactly the same with shellac/super glue/whatever and a sheet of paper…but why bother with the paper when you can use a heat source to melt the bond.

[Ian PParticipant @ianp]

In the video he explained that using tape on both surfaces allowed air bubbles to be burnished out. He avoided air getting trapped on the gluing surface by not fully covering the surface with superglue.

The machined part seemed to detach very easily compared with my carpet tape experience.

Ian P

[David TaylorParticipant @davidtaylor63402]

Ron, thanks for the tip about carpet tape.

Andrew, do you need to use coolant on brass? I never do. You could stand there and blow the chips away with an air nozzle which I did for the steel parts. That was just to ensure the cutter was only cutting 'new' metal.

I found with the GWizard software the feeds and speeds it gave me basically melted my cutters on the 1.6mm steel parts. Perhaps it assumes coolant. I did specify HSS cutters. I dialed things way back to basically what I'd do on the manual machine and the steel parts went smoothly (if slowly).

[HopperParticipant @hopper]

After the long and laborious task of making my own fabricated version of GH Thomas's Versatile Dividing Head some time back, I scored a full set of the castings on eBay UK today for just 30 Quid. Brilliant! Then of course there is the 30 Quid for shipping to Australia. But still a fraction of the cost of buying the castings new. And this lot includes the tailstock, an added bonus. Very pleased with my day's work.

So now the lad and I will be able to make a second VDH body with the correct centre height to suit our ML7. The first, fabricated version, was bored out on the Mighty Drummond and so its centre height is about 1/8" too high for the Wimpy Myford. Will just make up the new body and a spindle to suit and equip it with a disc with 24 holes for use in general indexing of common numbers. If we want to use it for gearcutting etc int he ML7, will swap the worm gear and index plates off the Drummond's fabricated VDH onto the new one. No way I'm making a second set of index plates with 814 holes to be drilled!

Eventually, I'll get around to using one of my growing collection of dividing heads to make the 14 gears to drive the cams and oil pumps in the quarter-scale WW2 Harley engine model that's in the works. One day…

[Neil WyattModerator @neilwyatt]

Posted by Hopper on 22/08/2018 09:27:37:

After the long and laborious task of making my own fabricated version of GH Thomas's Versatile Dividing Head some time back, I scored a full set of the castings on eBay UK today for just 30 Quid. Brilliant! Then of course there is the 30 Quid for shipping to Australia. But still a fraction of the cost of buying the castings new. And this lot includes the tailstock, an added bonus. Very pleased with my day's work.

So do I have to bin your article now…

Neil

[HopperParticipant @hopper]

Posted by Neil Wyatt on 22/08/2018 10:42:13:

Posted by Hopper on 22/08/2018 09:27:37:

After the long and laborious task of making my own fabricated version of GH Thomas's Versatile Dividing Head some time back, I scored a full set of the castings on eBay UK today for just 30 Quid. Brilliant! Then of course there is the 30 Quid for shipping to Australia. But still a fraction of the cost of buying the castings new. And this lot includes the tailstock, an added bonus. Very pleased with my day's work.

So do I have to bin your article now…

Neil

No way! 30-pound VDH castings come up but once a lifetime. So there's no chance of any dear reader being so lucky.

[Neil WyattModerator @neilwyatt]

Here's my print of Andrew's Burrell nameplate.

Two faults – first I forgot to recoat the bed with PVA so there's slight curl you can see at the front edge – my error.

Second, the descenders on the T and D in Ltd haven't printed. I did have print thin walls ticked so walls thinner than the 0.4mm nozzle diameter should have printed, but I think that with the very fine 0.06mm ~2 thou layer height this was expecting too much.

I could use a 0.2mm nozzle but then it would become a ~20 hour print instead of a five hour one…

If doing again I would speed up with thicker layers as there is very little vertical detail and use thinner walls, I had it on a robust setting better suited to 0.2mm layers.

Neil

[David TParticipant @davidt96864]

Posted by Hopper on 22/08/2018 10:49:05:

Posted by Neil Wyatt on 22/08/2018 10:42:13:

Posted by Hopper on 22/08/2018 09:27:37:

After the long and laborious task of making my own fabricated version of GH Thomas's Versatile Dividing Head some time back, I scored a full set of the castings on eBay UK today for just 30 Quid. Brilliant! Then of course there is the 30 Quid for shipping to Australia. But still a fraction of the cost of buying the castings new. And this lot includes the tailstock, an added bonus. Very pleased with my day's work.

So do I have to bin your article now…

Neil

No way! 30-pound VDH castings come up but once a lifetime. So there's no chance of any dear reader being so lucky.

I was watching that same set of castings; nearly pulled the trigger but decided to follow Harold Hall's route instead……..

[Anonymous]

Posted by Neil Wyatt on 22/08/2018 13:58:11:

Here's my print of Andrew's Burrell nameplate.

…………

Two faults – first I forgot to recoat the bed with PVA so there's slight curl you can see at the front edge – my error.

Second, the descenders on the T and D in Ltd haven't printed. I did have print thin walls ticked so walls thinner than the 0.4mm nozzle diameter should have printed, but I think that with the very fine 0.06mm ~2 thou layer height this was expecting too much.

I could use a 0.2mm nozzle but then it would become a ~20 hour print instead of a five hour one…

If doing again I would speed up with thicker layers as there is very little vertical detail and use thinner walls, I had it on a robust setting better suited to 0.2mm layers.

Looks good, although I'm not surprised it didn't print the T and D. Pity really because it means you can't show it and go ta da! Some of the letters seem well defined, but it seems strange that others, like the A, seem zigzig? If I get time over the weekend I may have a go at printing it myself.

Andrew

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