Member postings for Danny M2Z

Here's another of my favourites.

Nothing can be made 100% foolproof because fools are so ingenious.

I have been on the blunt end of this one a few times - once when a 'mate' managed to short out the electrical system of a Queenair 10,000 feet over the highlands of Nui Guinea. Same bloke screwed the decoding of a grid reference and I ended up in a mangrove swamp with our own 84mm mortar rounds landing nearby - when we got back I got a bollocking from the ASM for being away for so long. He (mate) had used 'yesterdays' code book. Fortunately the only damage was to my passenger's undies - it was his first deployment.

The trouble is, he was a really nice bloke and a good mate - just very dangerous.

Same mate built a 400W linear amplifier on 27MHz (CB) and asked me to help him sort it out - he had laid the directional yagi antenna in the attic but had a massive SWR - until I pointed out that he had a corrugated iron tin roof over it.

And then there was the time he gave me a lift, we filled up with petrol, he hit the transmit button on his boot mounted high powered CB and reset all the fuel pump gauges.

Like I said, fools can be very ingenious.

* Danny M *

Today I read a wonderful quote to the oldies club where I volunteer to help out.

Attributed to Albert Einstein, but I cannot confirm that.

“The difference between intelligence and stupidity is that there is a limit to intelligence".

They loved it, I hope that you do.

* Danny M *

Not exactly a lathe bible, this book has some very good machining techniques from the 40's. **LINK**

It's about gunsmithing, it's about 40Mb and it's a freebie.

* Danny M *

To prevent reamer chatter (when chambering a rifle for example), some gunsmiths advocate wrapping the flutes with waxed paper.

I am not sure why this works, maybe somebody has an explanation.

* Danny M *

Windy, you could make a decent still with all that stainless tubing.

Are you trying to re-claim the title of the World's Best Whisky?

Read it and weep - the best whisky in the world comes from Tasmania.

**LINK**

* Danny M *

Keep them both. As you gain experience you will be glad that you did.

Decent tenth's clocks are not cheap.

Welcome to the forum,

* Danny M *

The most annoying thing in my workshop is the operator.

I don't like to throw stuff away. So when faced with a boring job, half way through grinding a nice looking boring tool from 5% cobalt HSS I succumbed to laziness and gave the supplied brazed carbide @#*&^$ crap boring tools another go.

Nearly stuffed the job, gave it away just before it was ruined and finished the HSS tool grinding with great results, rescued the work.

We can be our own worst enemy.

The brazed tools now live in the tool cupboard with a note that says "HELLO STUPID, what do you want to ruin today?"

* Danny M *

Edited By Danny M2Z on 16/04/2015 08:23:09

Today I decided to make a tailstock threading adaptor for my mini-lathe as an aid for producing threaded spraybars (brass) for model engines.

Apart from the fact that I spent an hour or two grinding a boring tool from a 1/4" HSS blank (after trying the supplied and also binning the supplied chattering brazed insert rubbish) it was a pleasure to make a clean hole that fitted my circular split dies.

Add one more hour for reading up the great article by George H. Thomas (M.E. 3 June 1977) on Boring Tools.

I have a few questions:

1. How tight should one fit the split die into the adaptor body (does it need room to expand a bit and will the die run off-center if the hole is too big)?

2. What are the advantages/disadvantages of fitting a spring between the die-holder body and the chucking device? (I can see how it might apply positive pressure to the die, but then how much is too much)?

Dies are B.A. (of good Aussie quality ), 7/8" body dia with two locating pips and an expander slot, lathe chuck rotation is by manual labour.

* Danny M *

Like you said John, it's horses for courses.

As a club/shop purchase it could well justified.

For occasional use one would have to re-grind a lot of end mills to justify it's cost - but it is an interesting device.

As for my own efforts, I use a square block in conjunction with a Harold Hall designed simple grinding rest which gives satisfactory results for the end cutting edges. When I get a-round-tuit I plan to make the optional jig which permits sharpening the side cutting edges.

* Danny M *

Microwaves also have the property of disrupting your local home WiFi system (when they are working).

I tried this with a laptop. It's true - the signal bars dropped out when I was making a cuppa.

**LINK**

* Danny M *

Machining the guts out of one and precisely fitting an insert to give two heads or two tails is a very naughty old trick (one can get $50 a pop for them).

ANZAC day is almost here, and the ancient game of 'Two-Up' is a great Aussie tradition.

Probably the only day of the year when the 'authorities' turn a blind eye to a bit of gambling. (If you get caught with a double-headed penny though, you'd better know a good doctor).

As an ex-digger, I can confirm that it is true that my mates would bet on two flies walking up a wall!

In FNQ we once ran a book on cane toad races during one particularly boring field deployment.

As for spelling, one of the most unfriendly 'innovations' must surely be the 'Predictive Text' mobile phone.

Second to that would be this forum's software that puts cheesy little smiley faces into one's messages when all a bloke is trying to do is add a bit of punctuation!

Have a great Easter.

* Danny M *

Naughtyboy, WSP #38 Tool & Cutter Sharpening is very good. It also contains plans for two grinding rests and accessories.

* Danny M *

Citric acid is readily available in the foodstuff aisle at my local supermarket here in Oz.

Very useful to clean cartridge cases in an ultrasonic cleaner prior to reloading. Compared to my vibratory tumbler which takes hours to brighten the brass, three minutes in a cheap (Aldi) ultrasonic cleaner with a tablespoon of citric acid in a cup of water results in shiny cases and one doesn't have the problem of picking the media (crushed walnut shells) from the primer flash-holes. Unlike vinegar which leaves dark stains (from leaching zinc?) it gives a great result.

Bombmaking????? It's only lemon juice!

* Danny M *

Get yourself one of these - worth their weight in gold.

**LINK**

* Danny M *

Not quite model engineering, but today I heard the local fire engine blipping it's siren as it inched up the road with lights flashing.

A great Aussie tradition here in Victoria on Good Friday, the fire engine is followed by volunteers with collection tins. Kids and parents, dogs on leashes. Unlike some charities, one is not asked for an email address, phone number or any details - just a big smile and a thanks is the reward.

This is happening in every small town and hamlet here in Victoria - The local CFA fieries are also volunteers, only the large cities have the luxury of a fully paid service.

**LINK**

* Danny M *

Total lunar eclipse here down under

I have had this ruler for a while - how would one pronounce the units?

* Danny M *

According to this manufacturer, the Americans already have their own variation.

* Danny M *

Allegro razor blade sharpener.

Until relatively recently, razor blades for 'safety razors' were made from carbon steel.

I use them for cutting 'indoor' grades of carefully selected (expensive) balsa wood for competition model aircraft (Class F1D, designed to fly indoors for +30 minutes using rubber power).

It is important to make a 'clean' joint with no crushing for Unlike stainless steel razor blades, carbon steel razor blades may be 'snapped' to a very fine point, which is very useful for my hobby. It is also useful for sharpening small double edged model plane blades.

A lovely lady friend gave me this razor blade sharpening device that she had inherited from her father-in-law who was a Norwegian trawler captain during WWII.

I was/am fascinated by this precision tool and did some homework. In WWII steel and razor blades were in short supply so many a device was utilised to re-sharpen razor blades to gain a few more shaves.

As the first photograph illustrates, razor blade manufacturers were forced to reduce the thickness of blades due to wartime steel shortages.

Rubbing a blade around the inside of a glass was a popular trick and I found a few commercial sharpeners based on this technique, but my Allegro is very special. It's Swiss ancestry dates back to 1927.

It has a carrier that wipes the blade across a diagonal 3 position stone (coarse, fine and leather strop) tilts the blade on the return stroke for the other edge (via a cam) and at the end of the return stroke the blade is flipped 180 deg to repeat the process for the other side.

It also has a variable 3-position adjustment for blade pressure and replacement stone assemblies were available on request. Pure Swiss precision.

If you know anybody who flies competition indoor free flight models (F1D, EZB etc), watch their eyes light up if you offer them some unused carbon-steel razor blades!

* Danny M *

Ok, as this is getting away from the subject matter I started a little thread of its own about my razor blade sharpener as it is a fascinating device.

* Danny M *