Here is a list of all the postings fizzy has made in our forums. Click on a thread name to jump to the thread.
|Thread: Steam boiler|
With a bore of 1" and a stroke of 2" you will need a lot of steam. A customer bought two of our 5" diameter boilers to run a ham radio generating set running twin Victoria engines which worked well. **LINK**
|Thread: Taps and Dies|
A very basic rule I adopt when selecting dies which applies to tap and die sets is that if the die is split it is likely to be better quality than onw which isnt. No proff other than buying them for over forty years I have found this to be the case.
You need the same pitch as your bolts - modt likely coarse
|Thread: Machining Cylinder Head Chamber Roof - DIY or Shop Tool|
William, if your not intending to go for bigger valves then you are over thinking this. The modded chamber in the above photo has beed achieved using a high speed die grinder, ive done dozens of them and thats what they all look like. If all you are modding is the chambre you wont see much gain - the inlet throat is a nightmare design and requires extensive work. Get yourself the DV bible and all will be revealed. I can only assume you are turbocharging it as thats the only reason to open just the chamber and have such a low cr. Please do tell us what its for (sorry if you already have and ive missed it). Nostalgic stuff this is !
|Thread: Model Engineer's Auction|
|Thread: Machining Cylinder Head Chamber Roof - DIY or Shop Tool|
Thirty years ago I made good money modding 12G295 and 240 heads.Im assuming your increasing valve size? Cutter is easy to make if youve got a lathe - 120rpm. If your wanting high compression (13 to1 is as high as you go for normal fuel) then the chamber surfaces need to be ground smooth otherwise you will get detonation. Pillar drill - not a chance. An easier way to increase the seat size is with a conical grinder. If its just to lower the compression then die grinder - still got my Bosch die grinder somewhere - and wear goggles, forgot how many times I went to a and e with cast iton in my eye!
|Thread: Steam operated drain cocks|
Duncan - I opted for no.1 as it has a much lower surface area when closed so whould require less pressure to hold it shut, but either way should work.....I think
1. drain in
2. drain out
3. valve head
4. O ring
5. Gland nut
7. Out of shot - live steam line
Simples - perhaps all that time spent trying to get them to work wasnt a complete waste! Whats not shown is that you will also need a steam relief valve to release pressure to operate the valve.
|Thread: Cutting an exact diameter using a carbide tip.|
Agreeing with Andrew, we use nothing but carbide tips - you need the correct tip for the job but anyone who telly you they have to be deep fast cuts clearly doesnt know what they are talking about! No problem taking cuts of 0.0002"
Andrew - have you spotted your deliberate error? LOL
I got a mixed box containing several hundred for under a tenner so im good for a while. What are these people on?
|Thread: A Welding Problem - Steel Type?|
As an ex coded welder .....150 amps will struggle with 6mm plate even if its set up well and you are a very competent welder . Needs to be about 300 amps, spray not drip and 1.2 wire. What you are describing is what I would expect given equipment, material and experience
Could be yours for only £38 ish - have I missed something?
|Thread: Boiler stays|
If soldered correctly in the first place there is no problem in machining stays flat to the surface, the solder between the stay and the plate does all the work.
Whilst the regulations may require a permanent mark on the pressure gauge face plate, on smaller older gauges it is very unwise to attempt this as the retaining screws tend to corrode and snap off. New gauges come apart easily but must be handled with great care.
If your safety is unscrewing itself then something is badly wrong. As Nigel says, the spring should hold it plenty tight enough in place.
For most fittings I use fibre washers, but for brass plugs I use PTFE tape, and sometimes both if the direction of the fitting doesnt fall quire right. What a lot of people dont realise is that PTFE tape made for water pipes shouldnt be used for gas pipes. There are two types, one specifically for each application.
|Thread: 10TB HDD|
hdd backup has had its day, and im glad to be rid of them after so many fails. Everything on my pc is automatically backed up to the ms cloud so i can access everything anywhere. Will the cloud fail - unlikely given who runs mine.
|Thread: Shortening HSS drills|
Could you please provide an explanation of how stiffness (which is a function of Young's modulus and geometry) correlates to hardness. Thanks.
Lifted from the net - a bit vague but copvers the basics
The hardness (H) of a material tends to increase with an increase in the elastic modulus (E), yield strength (σy) and the strain-hardening exponent (n). Several materials with different combinations of elastic and plastic properties can exhibit identical true hardness (for a particular indenter geometry/apex angle). In general, combinations of materials that exhibit relatively low elastic modulus and high yield strength or strain-hardening exponents and those that exhibit relatively high elastic modulus and low yield strength or strain-hardening exponents exhibit similar hardness properties. Depending on the strain-hardening characteristics of the indented material, (i.e. n = 0 or ), the ratio H/σy ranges, respectively, from 2.2 to 2.6 or 2 to 20 (for indentations with a cone angle of 70.3°. The materials that have lower σy/E and higher n exhibit higher H/σy ratios. The commonly invoked relationship between hardness and the yield strength, i.e. H ≈ 3σy, is not generally valid or applicable for all power-law hardening materials. The indentation hardness of a power law hardening material can be taken as following the relationship H ≈ (2.1–2.8)σr where σr is the representative stress based on Tabor’s representative strain for a wide range of materials.
|Thread: Shipping to the EU - update|
As far as im aware amazon dont operate a courier service unless you are buying an item from them - I wish they did!
Pleased to report that a boiler which we shipped to Belguim last November arrived safely at its destination yesterday. Thats after writing it off as lost and sending the customer a free replacement item. I am still being hounded for Import Duty on my own item which was not delivered but was sent back to me. So much BS and stress!
|Thread: silver soldering|
As someone who buys their silver solder by the kilo (from the cup twins no less) take it from me that if you get your copper bright red there will be no flux left to flux. An easy way to ensure you dont over do the heat is to apply flux - HT5 is more forgiving - then cut off a snippet of solder from your rod and place it in the joint area. Evenly heat the job and at the point the snippet starts to turn liquidus apply flux rod. You may find it easier using 1mm or 1.5mm rod. And the super clean part - maybe years ago but technology has moved on since thene. It just needs to be free from surface debris, the flux does the job of cleaning far better that we can. And on a small item, dont be tempted to try to make a gap for the solder to run in to. capillary action and ipmerfect metal finish will ensure it finds its way everywhere it needs to. Wont be long before you crack it.
|Thread: Shipping to the EU - beware!|
Oops - not sure how that happened!
Cant even get it into first gear - stuck in neutral! Having played email tennis with someone at UPS customer services (no names on their emails) and asking what/why/when etc they firstly explained that they could do nothing without the shipping number....that would be the line in big bold green letters which starts with Shipping Number (I kid you not). They then referd me to their request 16th March asking for "Documents". No emails from them whatsoever in March, so I asks What document". No answer to this, nor indeed to any of the specific questions I asked. Instead a few lines of waffle refering to me paying a return shipping fee. What Return shipping fee? Ive been asked to pay an Import Tax? Finally customer services have suggested I ring a department to sort it out.....you guessed it, Customer ruddy services! They even supplied a number to call, the very same number that I tried every day last week, waited what must have amounted to several hours on hold but no one ever answers. Do you thing they are trying to fob me off! I have requested a meeting with my MP to discuss this issue - not holding my breath!
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