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The Regular Stuff: Chat, Buy, Sell, Off Topic, etc. => General Discussion - Model & Toy Steam Engines – Stirling Cycle – Flame Lickers – Small Antique Originals => Topic started by: Diverguy64 on April 15, 2021, 12:53:16 pm

Title: Boiler gauge glass replacement question
Post by: Diverguy64 on April 15, 2021, 12:53:16 pm
Good afternoon,
I just received in the mail a small kit with all the parts I need to replace the broken gauge glass for a Wilesco D12 that I bought at an auction. The little replacement kit has the new glass, all the little nuts and bolts, the stiff gasket with the holes to accommodate the tiny bolts ... and a slightly smaller, thick rubber gasket. It's the same diameter as the glass itself, but on which side of the glass does it go?
Title: Re: Boiler gauge glass replacement question
Post by: classixs on April 15, 2021, 02:22:08 pm
Never had an engine so new, that it had rubber gaskets in there, but would assume the rubber between boiler/glass, and the paper between the outer retaining ring/glass.
The only reason for a gasket on the outside, is to compensate for small imperfections in the retaining ring, so that it doesn´t stress the glass to crack again.
Title: Re: Boiler gauge glass replacement question
Post by: classixs on April 15, 2021, 02:47:04 pm
Would appear i was correct with my assumption.

Just cropped this D22 sightglass from a picture i lifted on Wilesco´s website.
Would appear to be paper under the outer retaining ring, unless your rubbergasket is white?

[attachimg=1]
Title: Re: Boiler gauge glass replacement question
Post by: Diverguy64 on April 15, 2021, 03:49:04 pm
Thanks for the advice. I think you’re correct, it goes between the glass and the boiler flange. However, the new replacement glass seems to be considerably thicker than the original glass, so with the rubber gasket in place, the retaining bolts aren’t long enough. Long story short, I installed it without the rubber gasket and it seems to run fine with no leaks.
Title: Re: Boiler gauge glass replacement question
Post by: classixs on April 15, 2021, 04:44:38 pm
Yes, the new glasses are way thicker than the old ones.

Good to hear you got it working again, even if a different approach had to be executed :)
Title: Re: Boiler gauge glass replacement question
Post by: Diverguy64 on April 15, 2021, 07:20:23 pm
If it does develop a leak, I’ll make my own much-thinner rubber gasket and reassemble. Too bad the new replacement glasses are so much thicker. You simply can’t use the proper nuts and bolts.
Title: Re: Boiler gauge glass replacement question
Post by: classixs on April 16, 2021, 02:52:42 am
You could make it yourself, and if not contact a local glazier, and get him to cut one for you in the correct thickness.

Made a couple myself, back when i collected Wilesco. They were made from unidentified scrap glas, and has held up fine.
However, later wisdom forces me to recommend a confirmed borosilicate glasstype, as it has a very low thermal expansion.
Title: Re: Boiler gauge glass replacement question
Post by: Trainmaster on February 21, 2023, 03:08:23 pm
I've read that in 1976, Wilesco switched to the thicker 4mm sight glass.  Prior to that I read that 3mm was used.  I ordered a 3mm x 37mm watch glass for my D-32 from 1965, so I'll see if it fits.
Title: Re: Boiler gauge glass replacement question
Post by: SteamerJ on February 22, 2023, 12:57:36 pm
You could make it yourself, and if not contact a local glazier, and get him to cut one for you in the correct thickness.

Made a couple myself, back when i collected Wilesco. They were made from unidentified scrap glas, and has held up fine.
However, later wisdom forces me to recommend a confirmed borosilicate glasstype, as it has a very low thermal expansion.

Jan I’m impressed! I worked at a sheet glass factory in my younger years and cutting circles are the hardest.
Title: Re: Boiler gauge glass replacement question
Post by: Trainmaster on March 26, 2023, 08:04:58 pm
A 3mm thick wrist watch glass from ebay worked perfectly on an older engine.  The new glass Wilesco sells is 4mm.  I used new Wilesco gaskets tightening the bolts alternately in three stages.  They don't have to be very tight.