Real Glass Cab windows (round)

[jma1009]

apologies if this has been mentioned before but can anyone please suggest either a source or method of making real glass windows?

diameter 1.5" thickness as near to 1/16" or 1.5mm as possible.

it is not something i've any experience of, having used perspex uptil now.

watch or clock repairer suppliers, or optical technicians?

or is there an easy method of making them in the workshop please?

any suggestions and help will be gratefully received.

cheers,
julian

[Deleted]

Julian
If you google 'Memory Glass' you'll find that which is shown in the pic. I have plenty spare if you want some! Postage only!
JB
modeleng.proboards.com/index.cgi?action=display&board=general&thread=5906&page=1

[RLWP]

Mine were made from microscope slide glass. I stuck them onto a flat disc in the lathe (with wax, I think), scribed a circle with a tungsten tipped tool (a scriber from memory), pulling the chuck around by hand (note, only go around once), removed the glass, then broke off the excess with a pair of pliers

I may have tidied the edges up with an oilstone as well

I only broke one using this process

Richard

[springbok]

HI RLWP
I want to put glass on my B1 Cab windows not plastic, do you think your method would work with non circular windows and not useing the lathe. would a template work! Would be very interested in hearing from you.
Regards
Bob

[jma1009]

thanks Richard for your reply and JB for your kind offer.

in between cutting an old bell clapper bearing in half for the frames i found this on the net this afternoon which may also be promising... flat ground watch glass in almost every conceivable thickness and diameter... U150 is £2.50 a glass.

www.watch-batteries.com/material/Round_Glass_Crystal_Flat.htm

cheers,
julian

[weary]

This previous thread has some good suggestions.
modeleng.proboards.com/index.cgi?action=display&board=general&thread=7704&page=1

I used 'simplyloco's suggestion of memory glass, and 'chris vine's punk methodology after scoring round the shape I wanted (square with rounded corners).

Worked for me and looks great!

Regards, Phil

[RLWP]

Bob, I have absolutely no idea

However, when I was a lad, in my Arthur Mee's Children's Encyclopaedia there was a drawing of someone cutting glass with a pair of scissors - with their hands in a bucket of water. Apparently the water damped vibrations and stopped the glass cracking.

I thought that was amazing as a child, and probably nonsense as an adult ;D

I would have a go at cutting the glass though. I would probably cut the curve first, then the straight bits and finish the corners with an oilstone. I'd expect to break a few, mind

Richard

[chris vine]

My slightly less punk grit blasting method would be much better I think. If you have a blast gun!

It is in the same thread that Weary has just pointed to....

Chris.

[Deleted]

Jan 24, 2013 16:54:21 GMT RLWP said:

I would have a go at cutting the glass though. I would probably cut the curve first, then the straight bits and finish the corners with an oilstone. I'd expect to break a few, mind

Richard

I thought hard about doing the shaped front windows on the Brit. Then I remembered: my partner has a lovely little vertical bobbin grinder with a 15mm diamond wheel. She uses it to shape her glass jewelry. As I gave it to her I might just claim a few rights!
Mind you, I now have a grit blaster......
JB

[uuu]

Has anyone tried approaching an optician (one of Julian's suggestions)? They must be trimming lens blanks to fit into frames all day.

[bobpendleton]

Jan 24, 2013 11:40:36 GMT jma1009 said:

...suggest either a source or method of making real glass windows?

diameter 1.5" thickness as near to 1/16" or 1.5mm as possible.

...any suggestions and help will be gratefully received.

cheers,
julian

May not be relevant (and I can't tell you how to cut 'em) but I do have a fair supply of 2" x 2" glass, unused, from the days when I made my own colour slides for projection.

Just let me know and we'll find a way to get them to you. In case there's a rush please mention the sort of quantity you can use.

Bob

[GWRdriver]

However, when I was a lad, in my Arthur Mee's Children's Encyclopaedia there was a drawing of someone cutting glass with a pair of scissors - with their hands in a bucket of water. Apparently the water damped vibrations and stopped the glass cracking.

Within the last two years I've read an article explaining this phenomenon. I can't now quote the technical particulars but as I understood it the water and glass interact on a molecular level and a chain reaction or cascade of separating glass molecules is created which promotes and in a way lubricates the cut. I haven't bothered to try it.

I'm having difficulty finding pre-cut glass rounds for my spectacle plate windows also and so far my attempts at circle cutting have not been successful. I would prefer glass also, but I may just be done with it and go to polycarbonate. One lesson to remember for next time is to see if glass rounds of the approximate size can be had first, and then machine the frames to suit.

[kwil]

Opticians trim lens blanks holding the subjest lens in a "jig" that matches the frame "window" against a lubricated grinding wheel of the correct edging profile.

[johnthepump]

Hi Julian,
Making round windows is really very easy. Mount a a piece of ply or chipboard onto you faceplate then a self adhesive cork tile to that, make a small pressure plate say for your job 1" in diameter centre drill one side and cork tile on the other side. Cut a square of glass larger than required and with the whole lot up in the lathe with a centre in the tailstock, mount a glass cutter in the toolpost at the required radius, bring it in contact with the glass pull the lathe round one turn no more. A little light oil on the cutter will help. Next take the glass out of the lathe & carefully make little cuts from the circle to the edge do this 4 times so that the waste is in quarters. Then very carefully tap along the cut lines.
Best Regards John.

[jma1009]

hi john,
thanks for the tip and for everyone else so far.
are you by anychnce 'john the pump' of godshill'?
cheers,
julian (atkins)

[Jim Scott]

Hi Julian

It is looking like watch glass is the easiest (if not cheapest) way to acquire plain circular windows for our Terriers. Your link to watch-batteries.com has produced, by return of post, 4-off, optically clear discs, accurately ground to 37.0mm dia x 1.5mm thick, all for a post paid price of £11.40. Don't ask your local jeweler, who will quote you an arm and a leg...

A check with my friendly optician suggests that almost every modern day spectacle lens is made from some sort of plastic these days so optical (spectacle) technicians may not be the way forward anyway. However, many Universities have glass working technicians, I know Newcastle has. This may be worth pursuing by those requiring more complicated window shapes.

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[jma1009]

hi jim,

that was quick! excellent!
i dont think at that price you can go wrong, so ive ordered a set too.

thanks everyone else for your very kind offers of help and advice.

i hope the link i found to www.watch-batteries.com may also be of use to others.

incidentally if anyone wants some 1/16" slightly opaque perspex used (apparently) for moped windscreens ive got 2 large sheets.

cheers,
julian

[uuu]

There is surely only one "John the pump", but are there 1008 other JMAs?

Wilf

[dscott]

Not wishing to advertise but I have fitted kitchens in the past for family and friends, and as my current day job seems to cover almost everything to do with other peoples homes flat pack furniture, shelves, lighting and decorating etc. And when I get home...

My wife runs an on line glasses business and as part of this there seems to be a full optical lab set up within the house with glass grinding facilities to almost any window shape seen on locomotives including round...when did I last get the chance to do any loco building and setting up of my workshop...but then again we have only been here 3 months or three bedrooms re-decorated!!

If this proves to be a required service I shall advertise in the proper section with approval from Alan Tel etc. All I will need is a shape in hard plastic that fits the window that the machine can follow.

David.

[jma1009]

david... you might have a productive sideline there!

wilf... surely one JMA is more than enough! the '1009' is my 3.5"g GWR KING's numberplates upside down i agree there can only be one 'john the pump'! long may he continue! we all go back along way!

cheers,
julian