Member postings for Ajohnw

I tend to favour older Jacob's 1/2" chucks. There are usually a number of them about on ebay etc but often they are 2 morse. 3 morse should be around as well.

Some years ago Rotagrip had a lot of used ones about and may still have them. No facilities for a draw bar though.

I have also used one of the heavy duty ones on this page but infrequently. Seems ok and well made to me.

**LINK**

Arbour from the same source.

John

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People might be curious about just what is the best grade of carbon for pistons Ian ?

John

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The Downham looks to be an excellent small machine BUT it would pay to remember that it uses collets and it would be best to find one with them, both metric and imperial. It might take a while to find one let alone the collets. It's the sort of machine that might crop up on the lathes co uk for sale section.

I have a Dore Westbury. A few other people on here have them. They are compact and can machine a fairly large area for their size. They have a 2 morse spindle which is a limitation but it's in a Myford lathe type spindle nose so things can also be attached via that. 2 Morse collets can be used and I also use an 2 Morse ER16 collet holder. Other sizes of ER collet holder are available. The only unhappy owner I have come across is the one I bought mine off. Usual things, inadequate vice and slides way too loose. They were built from kits and crop up now and again. There are details on Lathes co uk.

You can visit and buy used machines off dealers but prices are generally rather high compared with private sales and usually any extras will have been split of from the machine and will be sold separately. If people are prepared to take their time machines crop up that are sold with all sorts of things. Often sadly because some one has died or had to give up for one reason or another. My general advice on buying any machine is to wait until something crops up with plenty of kit.

Over budget but this far eastern milling machine deserves far more attention than it gets

**LINK**

Similar machines will be available from other sources.

People are inclined to say I want to change speed with a knob but there is no getting round the extra power available when speed is changed mechanically. This style of machine has been made in various sizes for as long as I can remember. You'll notice it weighs in at 300Kg which gives some idea of the rigidity it has. In real terms they are pretty serious machines for people who need that. It's what I would have if I had a little more space. Dore Westbury machines are also rather heavy for their size. Decent machines generally are.

Emco and Wabeco millers turn up used at times. Probably the best of the lighter weight machines. These do crop up used at times.

Don't rush what ever you buy especially if it's a used machine.

John

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Edited By John W1 on 27/12/2015 11:23:37

My wife is a good cook too but she cooks more or less 7 days a week with maybe 1 ready meal a month so only fair really for me to do some and anyway she prepares and cooks the veg etc. I just do the cooking now and again - and look after the practical things.

I also get the joy of doing the turkey sandwiches - real work but for me eating them is one of the best parts of Xmas washed down with a decent bottle red. Just had 3 door steps and 1/2 bottle of read.

John

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I had one of these a while back. They have increased the capacity across the width since then. With some pretty careful setting of the gibs it's not too bad to use. Unlike some it has a 3 morse spindle as well.

**LINK**

Little noisy due to the gears but not over the top. The owner after me was pleased with it too.

The one before me wasn't. Reckon to budget on a milling chuck and a good solid vice as well as the machine.

There is also a roughly similar machine from Sieg but I know nothing about it.

**LINK**

Arc are also a good place to look for a milling vice. There is a cheap one about that tilts and the tilt is held up by bits of plate steel - my advice would be don't. Go for a basic decent quality one.

John

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One of our local butchers gets in some award winning BP that is like that Richard. Of the "other" type I've found Lidl to be the best. Grilled rather than fried but I like it a bit crisp. If you happen to be around Clent Hills the cafe there does a great sandwich especially on their granary but I usually have a BLT. No charge for parking usually in the winter months.

I've had my suspicions about the so called fresh turkey we have been getting for several years so bought one from some where else this year. First one we've had that cooked well ahead of time for years. I use an American idea for cooking them. 20mins at Mk9 245C, have to turn half way through in our oven then 20min per pound plus 20 at mk 3/4 120C checking 2/3 through. I turned it breast down and reversed 1/2 way through that. Checking with a meat thermometer a nice even 80C everywhere 2/3 through. Then rest the bird for an hour if possible. Best buy an oven thermometer to set the oven that low and check now and again. I just hang it on the dish. I check the meat thermometers in boiling water just to be sure.

Last years turkey needed an hour over that - so much for fresh.

I cook stuffing separately. 2 good sized chopped and cooked onions per packet of stuffing along with a pack of sausage meat, a good teaspoon of garlic powder, salt and pepper and extra dried sage, heaped big tea spoon of that. Mix it all up well. I bought my wife a Keenwood a couple of years ago = easy. About an hour at 220C covered in foil. Generous amount of olive oil on the onions and microwave till soft. The neck of the bird can be stuffed but we are always in a rush in the morning so prepare and cook the stuffing while the turkey is cooking.

Xmas cake - I follow a recipe from the Guardian including making the marzipan and icing. I mix in some almond extract in the marzipan to give it a bit more of a kick. Maybe 2 table spoons of brandy over night on the dried mixed fruit and say 8 soaked into the cake over a week or so. Following my wife the marzipan is stuck on with marmalade. Her mon did that. Golden caster sugar is easy to get. I make the icing sugar from it with a hand held liquidiser with a poly bag over it to save breathing in the dust.

Model engineering aspect - we have a gas oven. Older ones used to have a sort of chute around the burner to make the heat circulate. The one we have tends to get hotter at the back.

John

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I had a used Meade 8" LX90, paid for with a 3 way split, me, my wife and my son - I insisted on paying for some of it. Much much cheaper than buying a new one. Then an odd mouse mat that has different granularity on each side, a quadcopter with a live video camera that feeds back to a phone or ipad etc, 2 good fictional books to read and as usual toooooo much chocolate but thankfully all is the dark sort.

John

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Reading lathes co uk I get the impression it uses a separate 2 speed motor for feeds and yet another single speed motor for milling. It mentions that the max milling speed is rather low for smaller diameter cutters.

If so the milling motor might be dual voltage so could be driven directly with an inverter. Or if pure 440v a single speed motor could be driven with a Transwave unit. These are fine if the instructions are followed. An inverter would allow the max speed to be increased. I would have thought that increasing the original 1900 rpm to 2,850 by driving up to 75Hz would be fine. Personally I wouldn't go any higher than that but some do. A lot of people also go for a more powerful motor when they convert like this so that the power is still there when it's slowed down. Personally I never run mine below 40Hz. People do go lower but only for very short periods.

You could also fit a 240v motor and add some sort of pulley arrangement to get more speed.

If it does use a dual speed motor for feed you might be stuck with changing it to a singles speed and then lacking the faster feed rates or not having the slower ones. It is possible to buy dual speed 240v motors but they are rather expensive. Looking at these some time ago there may be more than one type in terms of HP at each of the speeds. Not sure about that aspect.

Deckel get round the high speed aspect by offering a different head with it's own drive motor. My guess is that they wouldn't be selling it if it had this and all was ok.

All that running small cutters at lower speeds means is slower feed rates really. If it's in good order I wouldn't let that aspect put me off. I would want both the horizontal and vertical heads - trying to find these used could be something of a problem. Some wouldn't be bothered by not having the horizontal head but they are more ideal for certain types of work. eg During training I made a V block on one that didn't show any improvement in accuracy after is was ground.

John

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I've no idea how difficult it is to machine Brian but if I bought some I would think ahead and buy the largest diameter I could find within reason eg ebay 281456250113

I would have thought that brittleness was more of a problem. Elaborating on the "machining" instructions. Machine until it nearly goes in then switch to paper and then switch to paper by hand to finalise the fit. Pass - I've never done it. The bore would need to be smooth well finished and very parallel.

Could a mod arrange to do something about the way this forum often switches font size when something is pasted in from elsewhere. Also I find the normal font size just a little bit on the small size but that might just be me. I don't have this problem elsewhere though.

John

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Edited By John W1 on 26/12/2015 12:04:12

The ideal fit will drop through with an open end but feel springy if the other end is blocked - a challenge. Drawings I have seen suggest 0.0005" clearance on 0.6" dia. This would would behave like that.

Graphite rod seems a bit tricky to get in the UK. It is on ebay uk but only from China or the USA. I've seen suggestions that it should be polished and finally sized with photocopier type paper.

There is another source, well below UK import duty limits.

http://www.ebay.co.uk/itm/221629899565?ru=http%3A%2F%2Fwww.ebay.co.uk%2Fsch%2Fi.html%3F_from%3DR40%26_sacat%3D0%26_nkw%3D221629899565%26_rdc%3D1

John

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Edited By John W1 on 26/12/2015 10:42:21

Edited By John W1 on 26/12/2015 11:09:41

Merry Xmas All

At last I have the turkey on and the onions are nearly cooked for the stuffing. Just need to mix and get that in the oven now. Then whoopee it's Xmas.

John

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I'm inclined to keep stum on shortening a test tube which is probably made of borosilicate. It isn't soda glass tube which breaks cleanly and easily just via a groove cut with a decent file. You'll find all sorts of ideas for cutting tube around on the net. I have used the method outlined by Maurice on tube. I've tried hot wires, chalk and other ways but stick to what a laboratory man told me to do. Something very hot will cause soda glass to crack along a groove but it needs to be rather thick wire and chalk - waste of time.

Your idea of the lathe and a file sounds fine to me. Just keep working at it but it might be better to wait for some one who has done it to come along. Diamond disc - maybe but I can see that going wrong and chipping in unwanted places unless extreme care is taken especially when the tube is nearly cut through.

If you want to try a scratch build the person who designed this has a web site some where but plans are now all over the place

**LINK**

If I remember correctly he designed and built it for a present for his father.

John

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It's best to make the parts needed first before dismantling the lathe. I did but with ball races etc it's important to try and make sure that the all thread is central to the bearing when it's pulled in. Maybe a bit of a boss that locates in the shells on the discs used to "pull" them in. This probably doesn't matter on S7 bearings as they are so long but other types can be pulled in slightly slanted.

I managed to do it without that but it would be easier with the bosses. The same applies to getting the spindle out if the bearings are tight fit as they usually are. I had problems until I carefully squared things up by eye - it then needed less force. Maybe a sleeve that fits in the the spindle and locates the all thread centrally would be a good idea.

John

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I always wonder why people don't realise that some must be left when cleaning with solvents unless loads are used or there was next to none there in the first place.

If you can get hold of it there is a laboratory cleaner called teepol L. It's wonderful stuff for cleaning carburettor jets and should remove all traces of oil and grease.

**LINK**

I used to be able to "borrow" this when needed. Last time I looked there wasn't an easy on line source and my little bottle is empty. Looks like there is a source now, their on line shop.

John

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The 21t is usually on ebay. When the price is really silly it means not in stock until more come in. Might be worth messaging him to ask about the price - he might not have bothered to update yet>

John

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I probably mentioned in part IPA as I have just had a degreasing experience. An off topic one. My Xmas present, a used Meade 8" F10 SC telescope. As it can take a while to test under clear skies I use terrestrial objects and crazy magnifications. When I tried it I was a touch disappointed. Ok but hoped for better. I then did a torch test on the glass and mirror and thought oh dear so stripped it and cleaned it all. Initially with the usual window cleaner that comes in spray bottles. It's basically the same mix of IPA I mentioned. Then a wipe with IPA followed by the microfibre cloth. I tested it again this morning. Whoopee. It now focuses cleanly and crisply with a 3mm eyepiece in it. Very very slight signs of miss alignment but that's probably because the telescope is horizontal.

Anyway if some one wants to try an IPA mix window cleaner is readily available and cheap. The wetting agent is needed so that the water in it doesn't bead and allows it to dry more quickly and evenly.

John

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With aluminium you are probably better off not using a super smooth file. It's rather soft so can clog up the file. The actual size of the cut on a file can vary with the size of the file too. Smaller - finer. I need to get a couple of coarser cut small files off Aminster.

A drop of oil will help with the wet and dry. If I'm feeling manic I sometimes finish with a little abrasive rubber like block that is used for cleaning pcb contacts. Quick and easy and they last a long time. It's a very fine abrasive as pcb contacts are often gold plated. Metal polish will do it too but rags can catch in chucks which can result in lost fingers.

John

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Solvents are sort of interesting. Some these days for paint are marked for professional use only - extraction needed. The health people seem to think we can buy as much IPA as we like - not the beer. it's pretty readily available. Ebay for larger amounts. I've only used it to clean optical glass some a fairly large sizes. It seems to work a lot more effectively as 30% mix with distilled water plus a drop of wetting agent. I've used all sorts of things for this and it's pretty clear at this level that vast amounts can be needed to remove all signs of grease / oil / finger marks etc. Fortunately micro fibre cloths will remove the last traces for this sort of thing.

I'd guess industry use some variant of this for degreasing metals now.

**LINK**

They used to use tric. - the baths were more like swimming pools. Highly addictive too given long exposure to the fumes despite attempts to minimise them.

John

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It's the fit the drawings indicate between cylinders and pistons that is most important Brian not the precise sizes some slight variation on those wont matter.

The other aspect that matters on stirling engines is the phasing of the pistons. That usually corresponds to the distance between holes in linkages.

Stainless is sometimes used for the hot cylinder but borosilicate test tubes have lower thermal conductivity so may well be a better choice.

Red brass etc - it's more capable of running in close proximity to a cylinder than say aluminium or even mild steel which might well pick up and bind.

I assume that little program some one posted a link to calculates the step sizes to produce a radius. It's an easy way of doing it pretty precisely and finishing with a file after that is done is easy. Some people do the same thing on milling machines for the same reason. I might be tempted to buy a cutter. It's also possible to produce a decent rad by turning various angle chamfers and then smoothing with a file. Best for situations where the actual value doesn't matter too much.

John

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Personally if I was replacing the bearing I would fit a new spindle as well. There will be some wear in that. They should have spares stock. I asked and they had none but made some shortly after.

I intended to rescrape the bearing true but bought a boxford instead.

John

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