1. Existing barograph chart reference:
Firstly what chart are you currently using? Take the chart currently mounted on your barograph drum and look along the edge to check for a product code or chart reference. This will normally appear as a combination of numbers and letters such as 2MS or M/W/1915/X. If you can see a reference simply go to our online shop and select your papers from our catalogue. Once you have ordered a pack of charts from Metcheck we will keep your chart preference saved on file ready for next time you need a refill.
2. Barograph chart length:
The majority of barograph charts are 300mm in length that's around 12 inches. If you don't currently have a chart on your barograph; measure the circumference by wrapping a piece of paper around the drum and marking were the two ends overlap, then add about 5mm. This measurement is approximately the length of chart required. It is fine to pick a slightly longer chart but nothing shorter.
3. Barograph chart height:
Standard sized charts are 90mm in height that's around 3 ½ inches. If you don't currently have a chart on your barograph measure the height of the drum with a ruler or piece of string. A chart should not exceed the height of your barograph drum but can be 1 or 2mm shorter.
4. Measurement range:
This can be read off your current chart and matched to our stock accordingly, but if you don't have something to work from it can be a little harder. During manufacturing and restoration this process involves testing and calibration in a pressure chamber. Most old barographs of common size will generally measure 3 inches of mercury from 28 to 31 vertically (on a curved graph). The millibars equivalent would be 950 to 1050. Metcheck sell millibar charts as well as inch measuring charts.
5. What day of the week do you change your chart?
Most barograph charts are a Sunday or Monday start. Select your start day carefully as you will need to be available to go to your barograph and change the papers over ready for the upcoming week of recording.
6. Does your barograph have a clip?
The final consideration in selecting the perfect barograph chart is how to hold it in place. This is solely based on whether your barograph has a clip to hold the recording papers steady. If you do not have a clip on your instrument you will need the Metcheck Barograph Tape which is a double sided adhesive designed to be trimmed to the height of your chart and used to secure the papers in place.
If you cannot find your barograph charts in our online catalogue your first port of call is to email firstname.lastname@example.org with a picture or scan of your existing chart and we can match them as closely as possible. Once you have ordered a pack of charts from Metcheck we will keep your chart preference saved on file ready for next time you need a refill. Metcheck are able to order specialist charts; however, this can be a timely and costly exercise as we often require a minimum order or 300 charts (that's six years' worth of papers!)