Here is a list of all the postings Doubletop has made in our forums. Click on a thread name to jump to the thread.
|Thread: Cheapskate Sandblaster|
Yes I have garnet in my small cabinet blaster and wear a 3M respirator and hooded overalls as dust still gets out. I made the mistake of not wearing overalls once and after I took off the respirator started breathing the dust in my clothes.
Edited By Doubletop on 06/09/2019 23:08:34
Much as I had suspected, a total loss solution and cost effective if you live near a beach!
As for removing machining marks and other minor imperfections that's certainly one of the benefits of blasting parts. Far quicker than trying to blend with files and wet and dry. If you want a good finish give the job give it a blast, and then start with the wet and dry. Otherwise a great base for the etch primer. Just make sure all the running surfaces are well protected.
Edited By Doubletop on 06/09/2019 11:33:29
I've got one of the small cabinets and even though it is enclosed quite a bit of dust gets out. I've looked at these open air systems but have always wondered how much mess they make.
Although you are using kiln dried sand in your Kartcher I assume it runs wet so you soon have a pile of wet sand? Does that help contain the dust? Can the sand be adequately dried out to re-use it?
What is your experince?
|Thread: The Chocolate Fireguard as designed by Mercedes Benz|
The point I was trying to make. Or at least 41 similar points
Edited By Doubletop on 16/07/2019 21:24:08
|Thread: Electricity Supply|
Here we go, and no mention of EV's
More from Transpower. This time their views on battery storage from a grid owners perspective.
The conclusion being that its better done at the consumer end of the network. Which aligns with suggestion of using your EV as a battery backup and to feed power back to the grid. You EV probably has the biggest battery you own.
What it does to the lifecycle of the battery is another consideration.
Thats exactly what Transpower said in their document that I quoted
We will see the mainstream commercialisation of distributed solar, electric vehicles and energy management systems. These will start to significantly change the profile of demand and operation of the system with solar and batteries as well as other distributed energy resources enabling load to be partially flattened within a day but also adding additional intermittency. Despite growth in distributed supply, there will also be significant growth in grid energy demand. In the short and medium term we do not expect these batteries and distributed energy resources to be sufficient to flatten the daily or annual load curve, however it has an important potential to shave off peaks and it is critically important that it doesn’t accentuate existing peaks and troughs
The Australians already have the solution
But it may take a while and the wife and kids will have to fly..........
On a serious note it is encouraging to see that the we are now seeking formal documents on the subject rather than trotting out 'she'll be right', wind, solar, batteries and smart chargers will sort it...
I'm with you. A case of "The Emperors Clothes”.
At some point the stakeholders are going to have to wake up and realise that it is time to take this seriously rather than the piecemeal solutions that are being bandied about.
From Transpower the NZ grid network owner
" We will see the mainstream commercialisation of distributed solar, electric vehicles and energy management systems. These will start to significantly change the profile of demand and operation of the system with solar and batteries as well as other distributed energy resources enabling load to be partially flattened within a day but also adding additional intermittency. Despite growth in distributed supply, there will also be significant growth in grid energy demand. In the short and medium term we do not expect these batteries and distributed energy resources to be sufficient to flatten the daily or annual load curve, however it has an important potential to shave off peaks and it is critically important that it doesn’t accentuate existing peaks and troughs."
"Many of our existing assets will need significant investment in the next couple of decades. The assets of greatest concern are the conductors on some of our key 220 kV lines, many of which are built over urban areas. We need to sequence them carefully to manage our and our contractors’ resources, to avoid volatility in our transmission charges and to ensure sufficient capacity headroom to enable the grid outages required for the work.
Further future opportunities exist. New tools leveraging our data using learning algorithms such as artificial intelligence will increasingly play a role in managing the network as a complement to the distributed energy resources in individual homes and businesses. The increasing storage in the network could eventually create a network with extensive storage in which the grid’s role shifts."
Edited By Doubletop on 10/06/2019 03:54:09
Edited By Doubletop on 10/06/2019 03:55:09
|Thread: Model aircraft pilots angry over drone laws|
We are having a similar debate here in NZ following the Christchurch tragedy. The government quickly introduced a ban on automatic weapons and will introduce gun registration. The pro-gun lobby trotted out similar arguments about criminalising law abiding people and suggested criminals wouldn’t bother handing in their weapons or registering them.
Surely the point is that everybody that registers would potentially be off the list of suspects and the authorities will only have to spend their time dealing with the small percentage that don’t comply with the regulations.
Those of us with steam engines join a club and pay subs so we can get our boilers tested and approved for public use. We do it because we have to if we want to be safe and be insured to use them in public. Surely its much the same arguments for model aircraft?
|Thread: Electricity Supply|
In NZ the NZTA publish the vehicle registration statistics. In 2018 there was in the order of 200,000 new vehicle registrations. Those vehicles ranged from scooters to articulated trucks and larger.
The power ratings for every vehicle is given, and the average power of all the vehicles was around 100Kw. If the average annual mileage is assumed to be 10,000 miles (or 16000km) at say an average speed of 50km/hr then the average usage is 320hrs/year. Now those vehicles aren't going to be driven at full power so let’s say they are driven at 20% of the max power.
So 20% x 100Kw x 320hrs x 200,000 vehicles = 1,280,000 Megawatt/hrs of generation would be required. That’s a 150Megawatt power station running 24x7
There are 4Million vehicles registered in NZ. If they eventually all became electric then the power generation required would be 20 times that required for the 2018 registrations. That would be a 3,000Megawatt power station. The total generation capacity in NZ is currently 9,237Megawatts.
OK I accept there will be many other factors to be taken into consideration but surely somebody in the industry is doing a detailed analysis of what will be required and coming up with answers? Particularly; if we do need to generate this additional power how do we get it to where it is needed?
I've been looking for some sort of longer term planning or strategy for NZ. I've not found one and have assumed that with a deregulated electricity industry nobody wants to be the one to put up their hand and acknowledge there could be a problem.
I have found this from the UK though which may be a start
At the back are links to 218 other websites or papers related to the subject.
|Thread: The Chocolate Fireguard as designed by Mercedes Benz|
The link V8Eng provided led to this governemet strategy document. It may well be what I've been asking for
It looks like it is worth reading and right at the back 218 endnotes with links to other papers......
Edited By Doubletop on 20/05/2019 11:17:46
I think it means that if your neigbours have got home and plugged in before you you may well have to wait your turn alternatively they will load share and you may not get as much juice at the rate you expected. Broadband style.
Edited By Doubletop on 20/05/2019 11:00:29
Those of you in the IET may be interested in joining in on the discussion here. (not sure if others can access it)
One of the contributors provided this link
You may find it interesting
The previous post was made 12sec before mine but I can't modify the Scalextric reference now. However, it does look like they are on to it....
At the risk of undermining the serious debate going on here "Scalextric" rails? Stranger things have been tried.in the past. Atmospheric railways come to mind.
However, I am more interested in the planning for the immediate future rather than esoteric long-term options. It all seems a bit piecemeal at the moment, maybe Sainsburys can come up with a plan of their own?
So 174 miles at 6.2 miles per kWh is 28.06kWh from a 240v supply 116.9Ahrs. As 35amps have been quoted, as a charging rate, that's 3.35hrs to recharge.
We are not being Luddites here, we know something needs to be done and EV's look to be a promising solution. But the point being made is what is the plan to harness whatever energy source is going to be used and build the infrastructure to get the power to where people will need it?
There does seem to be a lot of “trust us” “she’ll be right” but not a lot of detail about any practical engineered solutions, short, medium or long term
We all know that electric vehicles in one form or other are here to stay. Every day we hear the virtues of this technology or that and benefits and features of one manufacturers approach as opposed to another’s
So, like any project, we’ve seen the brief, we’ve got some sort of business case, we are seeing the proof of concept, you can go and buy one. What we haven’t seen is any solid on-going forecasts or plans for how this is going to play out long term, particularly for the power infrastructure. Which is the point I’ve been making and we are now discussing.
I agree; my calculations are very ‘fag packet’ I cobbled them together from the information I had available, just to make the point. I could well be way off. I would expect that the power companies are working on this but would suspect that the answer could be too unpalatable to be made public. No doubt there are a number of our members from the power industry. Are they aware of anything in the public domain that they can share with us particularly around power consumption forecasting for the introduction of EV’s?
Maybe we should lobby the IET and get them to do an issue of Engineering and Technology (E&T) on the subject?
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