|
Post by Mr Stabby on Oct 27, 2016 21:20:58 GMT
Yoghurt Pot A tongue-in-cheek slang description of a GRP (glass reinforced plastic) cruiser. Tupperware PartyTwo or more yogurt pots in close proximity.
|
|
|
Post by bettina on Oct 29, 2016 18:49:56 GMT
Hi What's a skin fitting please? As in... The highest point of a calorifier (whether it is vertical or horizontal) will be fitted with a Pressure Release Valve (PRV) to prevent excess pressure from the hot water from splitting the tank. The PRV outlet can be piped to a skin fitting or the bilge. Read more: thunderboat.boards.net/thread/808/glossary-terms?page=2#ixzz4OV9QwNC5
|
|
|
Post by canaldweller on Oct 29, 2016 19:04:50 GMT
Hi What's a skin fitting please? As in... The highest point of a calorifier (whether it is vertical or horizontal) will be fitted with a Pressure Release Valve (PRV) to prevent excess pressure from the hot water from splitting the tank. The PRV outlet can be piped to a skin fitting or the bilge. Read more: thunderboat.boards.net/thread/808/glossary-terms?page=2#ixzz4OV9QwNC5Something to do with contraception I think.
|
|
|
Post by bettina on Oct 29, 2016 19:05:18 GMT
Hi guys, What is - Specific Gravity / Relative Density & what is the process for measuring it please As in..... A 12V battery is comprised of 6 supposedly identical cells. Of course, there is no such thing as truly identical, and some cells will deteriorate faster than others. This can be seen by measuring the Specific Gravity (Relative Density) of the cells. When the measurement of the cells begins to noticeably differ, it is time to perform an Equalisation Charge. Read more: thunderboat.boards.net/thread/808/glossary-terms?page=2#ixzz4OVCwasBHWhen replying, please try to keep it as simple/basic as possible and when possible use lay terms. Ta B~
|
|
|
Post by Telemachus on Oct 29, 2016 19:41:10 GMT
Hi What's a skin fitting please? As in... The highest point of a calorifier (whether it is vertical or horizontal) will be fitted with a Pressure Release Valve (PRV) to prevent excess pressure from the hot water from splitting the tank. The PRV outlet can be piped to a skin fitting or the bilge. Read more: thunderboat.boards.net/thread/808/glossary-terms?page=2#ixzz4OV9QwNC5A skin fitting is the plumbing fitting that, for example, allows the sink drain to run outside the boat. You drill a hole in the side of the boat (its skin) and then you need a fitting to connect to the sink drain pipe so that it goes overboard and stops the nasty canal water from getting inside the boat.
|
|
|
Post by Gone on Oct 29, 2016 19:46:22 GMT
Density also known as specific gravity. The density is the weight of a defined amount. This is usually stated as grams per millilitre(ml) or kilograms per litre. For example 1ml of water weighs 1g or 1kg per litre. Diesel which floats on water because it is 'lighter' than water has a density of 0.832kg/L or in english one litre weighs 832grams. With a battery the composition/concentration of the acid (a battery contains a mixture of sulphuric acid and water) will change as the battery becomes more or less charged. Another example is Antifreeze which is a mixture of ethylene glycol (occasionally propylene glycol) and water. The density of ethylene glycol is 1.10kg per litre. So if you measure the density of the mixture if it were 1.1kg/l it would be 100% ethylene glycol (often called glycol) and if the density is 1.0kg/L it would be 100% water. Where the density is between the two values it is because it is a mixture, you can therefore calculate the mixture from the density. Same with the battery, the density of the 'acid' depends upon the state of charge and so if you measure the density you can look at the tables and work out the state of charge. Make sense? Added - Just had a good curry and a few beers so I may be rambling
|
|
|
Post by Telemachus on Oct 29, 2016 19:52:58 GMT
Hi guys, What is - Specific Gravity / Relative Density & what is the process for measuring it please As in..... A 12V battery is comprised of 6 supposedly identical cells. Of course, there is no such thing as truly identical, and some cells will deteriorate faster than others. This can be seen by measuring the Specific Gravity (Relative Density) of the cells. When the measurement of the cells begins to noticeably differ, it is time to perform an Equalisation Charge. Read more: thunderboat.boards.net/thread/808/glossary-terms?page=2#ixzz4OVCwasBHWhen replying, please try to keep it as simple/basic as possible and when possible use lay terms. Ta B~ The electrolyte (liquid) in a battery is composed of water and sulphuric acid. The sulphuric acid is quite a bit heavier (more dense) than the water, so when they are mixed together in a fully charged battery, the density (weight) is quite a bit higher than water. As the battery discharges, the sulphuric acid is absorbed into the plates and so the electrolyte become more water and less acid, and so starts to get lighter and approaches the same weight (density) as water. Density of course is the weight (mass, really) per unit volume e.g. some number of Kg per litre. Water happens to weigh 1kg per litre. The relative density is the density of the liquid compared to water. So a fully charged battery might have electrolyte density of around 1.27kg per litre. So the relative density is the density of the electrolyte divided by the density of water. But since the density of water is 1 and when you divide something by 1 it is unchanged, the relative density in that case would be 1.27. As I said, as the battery discharges the density reduces and is thus a good guide to the state of charge. relative density is measured using a hydrometer which is just a float. The float will float higher in a dense liquid, it will float lower in a less dense liquid. Think "bathing in the Dead Sea". By putting a scale on the float, the relative density can be measured. One can also get refractometers which instead of measuring the density directly, measure it by how much it bends light.
|
|
|
Post by bettina on Oct 29, 2016 20:30:03 GMT
Hi What's a skin fitting please? As in... The highest point of a calorifier (whether it is vertical or horizontal) will be fitted with a Pressure Release Valve (PRV) to prevent excess pressure from the hot water from splitting the tank. The PRV outlet can be piped to a skin fitting or the bilge. Read more: thunderboat.boards.net/thread/808/glossary-terms?page=2#ixzz4OV9QwNC5A skin fitting is the plumbing fitting that, for example, allows the sink drain to run outside the boat. You drill a hole in the side of the boat (its skin) and then you need a fitting to connect to the sink drain pipe so that it goes overboard and stops the nasty canal water from getting inside the boat. Thanks Nick - I "get it" Density also known as specific gravity. The density is the weight of a defined amount. This is usually stated as grams per millilitre(ml) or kilograms per litre. For example 1ml of water weighs 1g or 1kg per litre. Diesel which floats on water because it is 'lighter' than water has a density of 0.832kg/L or in english one litre weighs 832grams. With a battery the composition/concentration of the acid (a battery contains a mixture of sulphuric acid and water) will change as the battery becomes more or less charged. Another example is Antifreeze which is a mixture of ethylene glycol (occasionally propylene glycol) and water. The density of ethylene glycol is 1.10kg per litre. So if you measure the density of the mixture if it were 1.1kg/l it would be 100% ethylene glycol (often called glycol) and if the density is 1.0kg/L it would be 100% water. Where the density is between the two values it is because it is a mixture, you can therefore calculate the mixture from the density. Same with the battery, the density of the 'acid' depends upon the state of charge and so if you measure the density you can look at the tables and work out the state of charge. Make sense? Added - Just had a good curry and a few beers so I may be rambling Thanks Chewy - I'll come back to this one in the morning and re-read it, bit on the techy/chemistry side, but I'm sure it will make more sense to me with a fresh brain & eyes Hi guys, What is - Specific Gravity / Relative Density & what is the process for measuring it please As in..... A 12V battery is comprised of 6 supposedly identical cells. Of course, there is no such thing as truly identical, and some cells will deteriorate faster than others. This can be seen by measuring the Specific Gravity (Relative Density) of the cells. When the measurement of the cells begins to noticeably differ, it is time to perform an Equalisation Charge. Read more: thunderboat.boards.net/thread/808/glossary-terms?page=2#ixzz4OVCwasBHWhen replying, please try to keep it as simple/basic as possible and when possible use lay terms. Ta B~ The electrolyte (liquid) in a battery is composed of water and sulphuric acid. The sulphuric acid is quite a bit heavier (more dense) than the water, so when they are mixed together in a fully charged battery, the density (weight) is quite a bit higher than water. As the battery discharges, the sulphuric acid is absorbed into the plates and so the electrolyte become more water and less acid, and so starts to get lighter and approaches the same weight (density) as water. Density of course is the weight (mass, really) per unit volume e.g. some number of Kg per litre. Water happens to weigh 1kg per litre. The relative density is the density of the liquid compared to water. So a fully charged battery might have electrolyte density of around 1.27kg per litre. So the relative density is the density of the electrolyte divided by the density of water. But since the density of water is 1 and when you divide something by 1 it is unchanged, the relative density in that case would be 1.27. As I said, as the battery discharges the density reduces and is thus a good guide to the state of charge. relative density is measured using a hydrometer which is just a float. The float will float higher in a dense liquid, it will float lower in a less dense liquid. Think "bathing in the Dead Sea". By putting a scale on the float, the relative density can be measured. One can also get refractometers which instead of measuring the density directly, measure it by how much it bends light. Nick, thanks again - I get "most" of it, right down to the hydrometer bit. So, he would need to remove some of the liquid from each cell of each battery to measure it? or just some liquid out of the battery to measure it? Now I know he's got a Turkey baster out the back with the rest of his tools that I am forbidden to ever use in the kitchen. I'm now wondering if he uses that to remove liquid from the batteries to measure. I'll ask him when he gets home tonight if he has a hydrometer. He must have I'm beginning to wish I'd taken chemistry as one of my electives in high-school rather than history & law and thanks for using as basic lay terms as possible - with examples
|
|
|
Post by tonyqj on Oct 29, 2016 20:37:07 GMT
All good explanations above. When I've got the time I'll put a much abbreviated version in the main Glossary up top.
|
|
|
Post by JohnV on Oct 29, 2016 21:50:55 GMT
A couple of items that could possibly be added to the glossary
Sheer ............................. the curve formed by the line of the gunwhale between bow and stern
tumblehome ....................an inward curve to a boats side after it has reached it's maximum width before it reaches the deck line
Rond anchor ....................an anchor with only one fluke for hammering into the bank to take a mooring line
|
|
|
Post by tonyqj on Oct 29, 2016 21:55:19 GMT
A couple of items that could possibly be added to the glossary Sheer ............................. the curve formed by the line of the gunwhale between bow and stern tumblehome ....................an inward curve to a boats side after it has reached it's maximum width before it reaches the deck line Rond anchor ....................an anchor with only one fluke for hammering into the bank to take a mooring line Great, thanks. 😀 I'll do them along with the above ones when I'm on a PC - too difficult to get the formatting right on a phone.
|
|
|
Post by Gone on Oct 29, 2016 22:05:58 GMT
If we were doing big boats we should include Roll, Pitch and Yaw but if we are limiting this to narrowboats in a ditch then there is no point.
These are unintended movements of the craft due to external influences such as waves, wind and currents. Roll - the rotation of the boat along the keel axis Pitch - the rotation of the boat about a horizontal axis at right angles to the boat keel - ie the bow going up and down. Yaw - the rotation of the boat about the vertical axis at right angles to the boat keel - ie turning left or right
I'm sure the pilots amongst us can come up with better definitions :-)
|
|
|
Post by tonyqj on Oct 29, 2016 22:10:17 GMT
If we were doing big boats we should include Roll, Pitch and Yaw but if we are limiting this to narrowboats in a ditch then there is no point. These are unintended movements of the craft due to external influences such as waves, wind and currents. Roll - the rotation of the boat along the keel axis Pitch - the rotation of the boat about a horizontal axis at right angles to the boat keel - ie the bow going up and down. Yaw - the rotation of the boat about the vertical axis at right angles to the boat keel - ie turning left or right I'm sure the pilots amongst us can come up with better definitions :-) Those are identical descriptions to an aircraft (well, maybe not the 'keel' bit 😏
|
|
|
Post by Telemachus on Oct 29, 2016 22:11:10 GMT
The electrolyte (liquid) in a battery is composed of water and sulphuric acid. The sulphuric acid is quite a bit heavier (more dense) than the water, so when they are mixed together in a fully charged battery, the density (weight) is quite a bit higher than water. As the battery discharges, the sulphuric acid is absorbed into the plates and so the electrolyte become more water and less acid, and so starts to get lighter and approaches the same weight (density) as water. Density of course is the weight (mass, really) per unit volume e.g. some number of Kg per litre. Water happens to weigh 1kg per litre. The relative density is the density of the liquid compared to water. So a fully charged battery might have electrolyte density of around 1.27kg per litre. So the relative density is the density of the electrolyte divided by the density of water. But since the density of water is 1 and when you divide something by 1 it is unchanged, the relative density in that case would be 1.27. As I said, as the battery discharges the density reduces and is thus a good guide to the state of charge. relative density is measured using a hydrometer which is just a float. The float will float higher in a dense liquid, it will float lower in a less dense liquid. Think "bathing in the Dead Sea". By putting a scale on the float, the relative density can be measured. One can also get refractometers which instead of measuring the density directly, measure it by how much it bends light. Nick, thanks again - I get "most" of it, right down to the hydrometer bit. So, he would need to remove some of the liquid from each cell of each battery to measure it? or just some liquid out of the battery to measure it? Now I know he's got a Turkey baster out the back with the rest of his tools that I am forbidden to ever use in the kitchen. I'm now wondering if he uses that to remove liquid from the batteries to measure. I'll ask him when he gets home tonight if he has a hydrometer. He must have I'm beginning to wish I'd taken chemistry as one of my electives in high-school rather than history & law and thanks for using as basic lay terms as possible - with examples generally a hydrometer consists of a thing that looks a bit like a turkey baster but inside the tube is the float thing. So you suck up the electrolyte from a cell and see how far the float sinks/floats inside. Once you have read it off you return the electrolyte to the cell. Generally cells SHOULD all have the same density but not always. personally I think using a hydrometer to routinely check the state of charge is only for masochists who also like holey clothes. Far too difficult! A hydrometer is a useful tool for checking battery health occasionally (e.g. Looking for differences between cells, checking for sulphation etc). I use mine about once every 6 months when I'm bored! It is if you like the "gold standard" but impractical for day to day use.
|
|
|
Post by Gone on Oct 29, 2016 22:17:16 GMT
If we were doing big boats we should include Roll, Pitch and Yaw but if we are limiting this to narrowboats in a ditch then there is no point. These are unintended movements of the craft due to external influences such as waves, wind and currents. Roll - the rotation of the boat along the keel axis Pitch - the rotation of the boat about a horizontal axis at right angles to the boat keel - ie the bow going up and down. Yaw - the rotation of the boat about the vertical axis at right angles to the boat keel - ie turning left or right I'm sure the pilots amongst us can come up with better definitions :-) Those are identical descriptions to an aircraft (well, maybe not the 'keel' bit 😏 Car designers also have targets for these on test circuits, especially yaw when heavy breaking.
|
|