Member postings for richardandtracy

You are looking for 0.676691729 turns of the handle each time (90/133)

With the 99 plate and 67 holes each time, you will get an error of 7.5947 x 10^-5 turns error each hole, or a total error of 0.0404 degrees. I am assuming the 99 plate is attached to the handle & rotates once per 4 degrees.

Regards,

Richard.

Edited By richardandtracy on 26/04/2018 13:52:36

Was reading 'Echoes of the Oil Country 4' last night & Bill Osborne talked of using a modified pressure gauge as a dial gauge. This was 1901/1902. Seems redundant pressure gauges have been used for other purposes for well over a century.

Regards,

Richard.

Interesting to see how they developed. The 1886 pattern 12" mortar is much more sophisticated in its carriage: **LINK**

Regards,

Richard.

Cap heads are grade 12.9 (1200 N/mm^2 ultimate, 1080 N/mm^2 0.2% Proof). Hex head screws/bolts are usually grade 8.8 (800 N/mm^2 ultimate, 640 N/mm^2 0.2% proof) or weaker. If not marked, hex heads are grade 4.6, (400 N/mm^2 ultimate, 240 N/mm^2 proof), same with studding. Nuts are grade 8 by default, and are at least as strong as a grade 8.8 bolt/screw.

The grade 12.9 material is less shock tolerant. So, for strength use cap heads, for shock tolerance, use hex heads.

The head of a grade 10.9 button head is weaker than the thread, and under tension a button head will have its head pop off before the thread snaps.

Regards,

Richard.

Edited By richardandtracy on 26/04/2018 12:20:25

Phweee

There are some incredibly skilled & patient people around. Thanks for the links. Foolishly I looked for N.A.M.E.S 2018 on Google too. Based on that I understand someone irrelevant has done what many mothers do - had a third one quite quickly. Oh joy.

Richard

Kapa Board is available in the UK. Not in 4mm, but 3 & 5mm, both of which are closer to 4 than 6mm. May help a little.

Regards,

Richard.

I played about with the location from MichaelG and attached bracketry to allow a cheap & nasty vernier calliper to be attached. I used the idea of the depth measuring rod to attach to the quill, but had to replace the stainless rod that came with the calliper with a longer 3x1mm carbon fibre rod bonded in with epoxy. Both ends of the calliper can be moved to re-set the zero where necessary.

The fixture is as below:

No permanent mods to the machine were necessary, and everything is reversible.

I attached a gib clamp lever on the cross slide through a ready tapped hole in the side of the saddle, obviously put there by Warco for that purpose without ever mentioning it in the handbook. The cross slide dial is set up for diameter turning, and it's an effort to remember that the movement is half what the dial says.

Did my first real milling over the weekend (made 5 Tee Nuts - wow, so complicated!) and now can claim I'm starting to be a beginner. It was much easier with the cross slide clamp & the quill scale than it ever was before. Thanks for your advice. At some point I will fit a prop behind the milling head to prevent it rotating about the lathe headstock & improve the stiffness further.

Regards,

Richard.

Planning on doing exactly the same thing myself, but in an aluminium block. The only difference is that our machinist at work suggested angling the block at 30° and machining the dovetail with a slot mill. If the back face of the dovetail groove is not flat, what of it? Makes sense, but until I've tried it on a practice piece I'm a bit nervous of the idea. Apparently he did it for home use with his 250-201 toolholders.

Mt first guess would be to treat as an HSS mill of the same diameter of the largest part.

I await answers with anticipation too.

Regards

Richard.

Can I suggest you look on http://archive.org and do a search for the 6" MkXII Naval gun manual from 1917. They have a handbook for the gun and gizmos, with drawings at the end of the book of both the barrel and gubbins. Only the barrel is dimensioned, though.

If everything is perfectly made, if the surface is perfectly smooth, if there will be no micro-welding under the theoretically infinite forces of infinitely rigid gear teeth surfaces, then no lubrication is needed.

In reality, the wheels are not infinitely stiff, the wheel is not perfectly smooth and not perfectly made, either. All this imperfection leads to small sliding movements that degrade the surface, and lubrication reduces the degradation rate to acceptable levels. If the two were perfectly made etc, then there is likely to be micro welding, which degrades the surface and starts wear - so lubrication is used to reduce the probability of micro welding to acceptable levels by leaving a non-weldable molecule between the two surfaces.

Taking this limit explanation shows why it's needed.

Regards,

Richard.

If you are interested in a program to calculate the line positions for you, take a look at my web site at http://www.chestnutpens.co.uk/misc/sundial.html

Hope this is of interest,

Regards

Richard.

Difficult, but possible. Hand fitting is needed.

Regards

Richard.

A few years back I had a hard drive recorder fail at age 4 months. I took it back to Curry's clutching a printed copy of the Sale of Goods Act, and after making such a fuss that the Manager came out, they honoured their legal obligations. In full.

Regards,

Richard.

66mm is about 2 5/8", so probably imperial.

Our local stockist has mostly inch stock quoted in mm, but as imperial dies wear out, they're replaced with the nearest sensible metric, eg 8x4x1/4" box is now 200x80x6mm

Regards,

Richard.

When I hear 'Devon' & 'Zummezet' I feel as if I've come home, but rarely speak with any residual accent 31 years after moving to Kent, and now I've lost most of the dialect words too. Blank looks from 'Men of Kent' or 'Kentish Men' tend to reduce the dialect injection rapidly.

And what a trivial distinction, if there ever was one, it is between 'Men of Kent' or 'Kentish Men', especially when you have to consider they furriners on 'tother side of Tamar and how different they are from the English. I'd just like to say, afore things get nasty, 50% of my ancestors prior to 1900 never set foot on the English side of the Tamar.

Regards,

Richard.

I had a look, but all acrylics seem to be cast outside the UK. I think one of the monomers is covered by the psychoactive substances regulations. It also needs to be cast in a pressure pot to crush bubbles. Polyester is very brittle, polyurethane is too soft to polish up adequately, and epoxy seems to discolour over time.

Regards

Richard.

Edited By richardandtracy on 15/04/2018 12:20:45

The process is certainly done with Micro SD cards, the smaller size ones being big ones formatted not to use an area that fails.

Regards

Richard.

Of those who stop at my stall, about 50% say they remember using fountain pens and how nice they were, about 25% consider ones for presents and the remainder consider them for themselves. The materials available are very attractive, and kit pens do look flashy and relatively posh. I really want to sell custom fountain pens, where only the nib & feed is bought in, but taking 15-20 hours work for a one-off is not viable to sell. Going into production, even ona small scale would cut the unit time by a lot, but it bores me rigid doing the same thing time after time.

While people do not write a lot, there is still a certain cachet associated with using a fountain pen, and they feel so good to use if the nib is correctly tuned. Personally I always use one, having a pens dating back to c1915 in fairly regular use, and a box on my bedside locker of 25 inked up pens, from which I choose 2-3 every day. I regret to say, my little collection probably exceeds 200, of which Parker pens form at least 50%.

Regards

Richard.

Went to a craft fair today to sell kit pens. Today was as slow as every other fair in the last year-18 months. People want to hang onto their dosh. The only pen I sold was the nicest of the lot, made from the same material as many exquisite blue Conway Stewart fountain pens. The guy I bought the blanks from bought up the stock at the CS liquidation sale a few years ago and is selling it off to pen makers. The stuff goes for about £10,000 a tonne at the prices he's selling it at. Shame acrylics are well nigh impossible to cast at home.

Regards

Richard.

I have an MT4/ER32 collet chuck. I can see the needle on my dial gauge move, but it's less than 0.01mm. Not bad for a £22 inc postage collet chuck direct from China.

Could I buy the material for much less than that? Don't think so.

The question has to be: Do you enjoy making tools, or making stuff with tools? For me making the stuff with tools is what I want to do, and if the time making the tool is excessive (saving less than £2/hr) I'll buy not make. A collet chuck may be quick for some, but not me. And the accuracy of my cheap chuck is at least as good as I could make.

Regards

Richard.