Here is a list of all the postings lee webster has made in our forums. Click on a thread name to jump to the thread.
|Thread: To Cap It All|
The radiator cap on my 1930 A7 special is a steel plumbing fitting of the correct thread with an old penny placed on the top which was then covered with plastic filler and carved to shape. Made some 60 years ago. Not by me I might add, but I approve!
|Thread: cutting spur gears on a mill|
Sketchup is good fer what it's good fer. Creating slightly cartoonish drawings that dont have much in the way of chamfer or fillet. I have designed many things with good 'ol SU, but I wouldn't use it for cad work. If I could afford it I would use Solidworks. I can't so I don't. I spent a year or two learning Freecad. Don't go down that route. F360 lost my respect long ago. If you want to be one of their unpaid testers using hobbled software, go for it. But before you do, try DesignSpark mechanical. You can't produce technical drawings with it, but seeing as I can't read 'em I don't need 'em. Designspark has been an eye-opener for me. It has limitations, but I can live with those. And it's free. My fave word.
|Thread: Aldi belt & disc sander|
The one I bought from Aldi is poorly made and inaccurate. I thought it would be a re-badged tool from the far east, but it appears to be German made. It does however remove metal or wood quite well, just not with a great degree of accuracy. I have seen old used belt/disc sanders (not Aldi brand) at car boots etc, and they seem to be well made. I am sure the Aldi model could be made a lot better if I had the time.
|Thread: Good workshop practice? NO.|
I couldn't agree more Nigel. My shopping list gets longer every day!
Thanks Speedy, I already have two of the drawings. Very useful they are too.
Even with the nut in place the puller bolt locates on the end of the crankshaft without touching the threads. Mind you, a badly alligned puller could damage the threads. I think the crankshaft is OK, they are prone to breaking, but I won't know until I remove it. It could be a spare engine for someone once I have finished with it.
Bob, the engine is about 1930, two bearing with dynamo.
brian jones 11, An Austin Seven flywheel can "fly" off the taper if you are not carefull. The suggested way is to leave the nut on the crankshaft, but loosened. I didn't do that!
Russell, The flywheel taper and rear hub taper are both a bit suspect. I lapped a flywheel onto its taper many years ago. That quietened it down.
I have a confession to make. I have started to dismantle my Austin Seven engine so that I can start designing the half size model. (Is it half size or half scale?) Today I wanted to remove the flywheel which is held onto the crankshaft by a taper and large nut. The nut was easy to remove and I have a flywheel puller. It consists of a bar of steel an inch wide by ¾” thick by about 2 ½” long. It has a threaded hole in the middle and 2 holes that line up with 2 blind threaded holes in the flywheel. All threads are ½” BSF. My puller was missing the central bolt. I remembered that the last time I used it to remove a flywheel I had to use a lot of heat, brute force and swearing. It took several days to get that particular flywheel off, and the middle bolt was beyond saving. So, I had a puller, but no very important bolt and ½” BSF isn’t available locally. I found a piece of steel rod about the right diameter, and I had a ½” BSF die. What I didn’t have was the correct die holder. I had bigger and smaller, but not the right size. There was only one thing I could do. Sorry, you might want to cover your ears. With the steel rod clamped in the vice I used a pair of water pump pliers to turn the die. I cut about 1 ½” of (wonky) thread and screwed the puller into the 2 flywheel holes and tightened down my home made bolt. It seemed to be working until I realised that one of the flywheel bolts was pulling out of its thread. The flywheel threaded holes are only about ½” deep at the most. I removed the bolts and cleaned out the holes as much as I could. Re-assembled and tightened I started to hit the middle bolt very hard. Several moments later the flywheel sprung off the taper and I could remove it. I still have the crankshaft to remove, then I can measure the crankcase and produce a 3D drawing before 3D printing it.
|Thread: Drill powered nibblers - buying advice sought.|
As mentioned above, noisy, messy, more messy, difficult to control, messy. Bought one used it a couple of times threw it away. Best thing I did was throw it away. I would rather bite my way through metal than use one of those.
|Thread: 'Puter upgrade recommendations|
Fusion 360 is cloud based I believe. How fast is your internet connection?
I am using Solidedge 2021 on a very simple laptop with an SSD but no internet connection and it is so fast! Solidedge loads in about 4 seconds. Designspark loads in about the same time. I hate to think how much slower it would be if it was connected to the WWW.
|Thread: Sieg baby lathe not starting|
A friend looked after my old lathe for a while. When it stopped working he discovered that the motor had got damp. It was removed and placed in a warm oven for a few hours. Fixed.
|Thread: 2D and 3D Cad Software Recommendations|
I have been using FreeCAD for a year or two now. It is "buggy" to say the least, but very good for producing some great 3d parts for 3d printing. It wasn't up to what I hope to do so I too downloaded the community version of Solid Edge. A very powerful programme that is going to take some learning. I also decided to re-try DesignSpark Mechanical. I stopped using it when I decided to concentrate on FreeCAD, but getting back into DS with some design experience under my belt I am surprised at how good it is. I believe there is also a way to produce 2d drawings. Something I haven't explored yet. I still use FreeCAD for my one-off simple parts. It will work 90% of the time. The other 10% is what is so annoying about FC.
|Thread: Have You considered getting a 3D printer|
If I hadn't got myself an Ender3, I wouldn't be casting metal. I don't think I could ever have produced the patterns I use without my E3. I am now in the market for a resin 3D printer, a big one!
|Thread: Light weight building block forge|
Well, what an eventful few days since my last posting about trying to find suppliers of materials to make a foundry. I discovered that pottery suppliers usually stock most of the materials I needed, but I couldn’t find a supplier in Cornwall. A web search turned up many potters, but only 1 supplier who had shut down a few years ago. I sent an email to one of the potters asking where he got his materials from and the reply was the supplier who had shut down. He hadn’t shut down, just moved 500 yards round the corner. I went to see him and got both the sodium silicate and some silica sand, but no refractory blocks. When I returned home I sent an email to the potter thanking him and continued my search along a different tack, I would search for people casting metal hereabouts and ask them who supplied them. I left an email with a local business that is an engineering company that also casts metal, JW Engineering of Camborne, Cornwall. Five minutes later they phoned me inviting me to a pour today 10th Nov. I went along and watched as John was timing the melt of 25kg of cast iron in his home made foundry. Before long John and his wife Angela helped by their son used a small crane to lift the crucible out of the foundry and poured the iron into two moulds. A second smaller melt filled the third mould. If that wasn’t enough the potter has sent me an email stating that he probably has some spare refractory blocks I could have. I am arranging a suitable time to meet up. If all goes to plan I could have a foundry up and melting by next weekend, but I have family visiting so that could slow me down a bit. Meanwhile I will experiment with the sodium silicate and silica sand to see what sort of mould I can produce. Because of the shape of the cylinder block I think I will have make the mould in six parts, four sides and top and bottom. The sides will have to be semi self-supporting, green sand won’t do that. That is why I need try different strengths of sodium and silica to find a mix that will hold its shape with very little framework.
Thanks Dave, I have found a supplier closer to me than Wales, CTM potters supplies in Exeter. I will keep looking. Lee
Has anyone any experience of building a forge/furnace using a light weight building block like Thermalite or Celcon? I would like to use proper foundry blocks to build a forge (is it forge or furnace?) but I am having difficulty sourcing them locally, I live in Illogan Cornwall. I have watched some videos on youtube where small forges/furnaces have been built using a building block instead. They seem to work. I would line mine with fire cement and heat it electrically not with a gas torch.
|Thread: 3D parts printing undersize|
I will take on board all suggestions. I am very much 'playing it by ear'. My printer should be here on Monday. I will do a trial print of the head or block, less plastic to print a head, and then measure. I am not adding any of the stud holes to head or block, I think it will be easier to drill them in the castings.
|Thread: Be gentle with me.|
I re-connected my cad computer to the internet yesterday to allow F360 to update its licence. All my old drawings were gone from the left hand panel, can't remember what it's called, but I still had a copy of the drawings on my HD. I started to use it and soon remembered another reason why I stopped using it. I don't like the dimensioning tool, in fact I don't like most of the tools and the method of selecting them in F360. I suppose I am more used to FreeCAD and Solidworks to bother with Fusion. I am not sure if I will ever need to see my design 'working'. But my main dislike of F360 was the internet connection. I had it installed for many months before I tried it without the internet on my back-up computer, it fell over and refused to work. One of the reasons I never upgraded Sketchup 2017 is because the later version is cloud based.
94cc! Thats almost two mopeds!
3D printer now on order for delivery Monday. If my designs print out OK I will post pictures.
|Thread: 3D parts printing undersize|
I watched a video on youtube this evening where the poster showed that 3D parts print undersize because of filament shrinkage, about half a percent. I don't know if this applies to resin printed parts. I hope I can post a link to the video here.
What really interested me was that I am designing parts to print out and I would have to enlarge the design by the shrinkage of the metal being used in the casting. I thought I would have to do this in my cad programme, it seems it can also be done in the printer software. Does this mean I could design full size parts, a scale of 1:1, and then tell the printer to change the scale to suit? factoring in shrinkage for the filament and the metal of course!
|Thread: Be gentle with me.|
Thanks to all for the replies. I had originally thought I would make the model 1/4 scale, but that looked awfully small when I started to draw it. I then decided that 1/2 scale would be easier for me, this is my first attempt at model engineering. OH! I can hear the groans already! Start small, make something easy. I know I should, but there's something broken inside me that says, you can do it. I then dallied with 1/3 scale before listening to reason(?) and I have settled on 1/2 scale with 1/3 on the back burner. I know I have taken on a large task, but I built my first full size A7 in a garage 7 miles from home with no electricity. I love a challange! The only challange I don't feel up to is making cast iron parts. I will have to make most of the engine in aluminium and then paint it to look like a display engine, I don't mind that.
The comments made by SOD about F360 are one of the reasons I stopped using it. I felt that exploring the creation of joints would take me away from learning to design the engine. I now see the point behind watching a working model in action on screen. I have all my cad programmes on a second computer (second hand but very well specced) which is very rarely connected to the WWW. Fusion is supposed to run without internet connection, but it refuses to on mine. Both Solidworks and FreeCAD are happy, for the moment, to not be online.
My next purchase will be a 3D printer so I can print the parts I have drawn, the block and the head, and figure out how to make the moulds. I had considered the lost pla way of casting parts, which is why I will probably buy that type of printer rather than the type that prints at a much higher resolution with resin. I would like to make moulde I can re-use. When I have the parts printed I will post them online.
Neil, do you mean that a scale model sometimes doesn't look like the real thing scalled down? A friend used to build scale model locos and said once that some of the dimensions were "out" to make the model look more like the real thing. It's a shame he doesn't live in Cornwall anymore because he was also an A7 owner.
I have joined other model engineering forums (forii?) recently, so if you have read a post from me somewhere else, you've heard it all before.
I am hoping to build a working scale model of a 1930 Austin Seven engine. I have two good full size drawings and a real engine I can strip down and measure. I am teaching myself to use 3D cad programmes, I seem to have settled on FreeCAD even though I also have Fusion 360 and Solidworks. I am now looking to buy a 3D printer so I can see what the model will look like and figure out how to make the moulds for the castings. I would prefer to use cast iron for the block, head and crankshaft, but I might have to settle on aluminium for the first two and steel for the crank. I have seen other A7 engines and now realise what a task I have set myself. I can't wait for the day I fire the engine up!
Lee. (Illogan, Cornwall)
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