Here is a list of all the postings jaCK Hobson has made in our forums. Click on a thread name to jump to the thread.
|Thread: METAL DUST & VFDs|
I have had a vfd die and a couple stop working but come back to life after opening up and dusting with a brush.
I now have VFD in a large enclosure covered by a cloth.. .e,g, on a middle shelf with cloth pinned across the top and bottom shelf, or in a plastic box with cloth draped over it.. No problems since doing this. The forced air enclosure above is better and smaller and looks pro, but as a quick soln, simple works (I've been running like this for years).
|Thread: Workshop warming|
I got a heated vest/gilet which works very well. Mine has a heated collar which is nice.
Edited By jaCK Hobson on 28/04/2022 13:31:37
|Thread: Blobs on 3D print..|
I couldn't get on with Octopi until I ran the pi from the Ender power supply. The stepper motors caused too much noise.
So now I run the 20Vfrom my ender supply into a voltage converter to drive the pi. No comms problems since...
|Thread: It's About Time!|
What a fun day! Not as busy as previous years but that meant that the visitors could really engage. I didn't get a chance to take a break so managed to bore many people with long explanations of active damping applied to my 3d printer.
I don't think there is anything quite like this anywhere else. The South London Branch of the BHI is probably the biggest. I'll try and give more warning next time...
I think morrisons etc is fine for most visitors - I think 3 hour limit. Worst case, move the car from one to other - 6 hours!
If disabled then talk to the people at the soper hall barrier and you might get special treatment.
Unlimited parking is available up the road... but it is a bit less than a mile to walk back
Sorry about the website. That is an oversight
Edited By jaCK Hobson on 21/04/2022 12:25:29
I'm going to be showing off 3D printing on my table... Lots of other better exhibits. Should be a good day and maybe worth up to an hours commute - you will be able to spend more than an hour at the event without getting bored.
|Thread: Acceptable runout on drill chuck|
Thanks for the tip on using the draw bar to remove the chuck. Simples with some parallels. I used similar idea (3/4" pipe sleeve and bolt/washers) on MT2.
Deburring the R8 adaptor with a fine diamond stone got the total runout down to .1mm and .06mm measured of the J6 taper of the adaptor. I think it reasonable to expect .01mm on a reasonable quality adaptor so I will get one. .04mm on cheap 3 jaw keyed 16mm chuck is probably what can be expected?
I might buy another chuck for small drills...
Edited By jaCK Hobson on 29/03/2022 13:16:33
For comparison, I had a check of my new Sieg 3.5. This is the first time I use the drill chuck (which was supplied with machine as part of the standard package).
If I measure runout on a quality hss 10mm endmill held in 3 jaw chuck, I get in the region of .25mm runout. Not what I hoped for at all as it is clearly visible and not what I'm used to. Disappointing if I'm using 1mm drills, which was my intention. Any tips on how to get a chuck off a J6 taper so I can compare with other chucks I have? I suspect the R8 adaptor makes a significant contribution as it is not the same quality of finish as that of the separate 10mm collet I got at the same time.
Runout on the same 10mm end-mill in a R8 collet is difficult to measure - I think the movement on my .01mm indicator is due to lack of stiffness in the mill. So I would guess .01 or less. The collet is std from Arc - not std with the Sieg. Does any of this matter if the mill isn't that stiff? Applying hand pressure (maybe 5-7kg) to the head in x directon, with all axis gibs locked, gives .4mm deflection. Much more than I would have guessed.
I got no idea if any of that is good or bad. Not a clue, but I would be much happier if I hadn't measured it Can someone cheer me up?
Edited By jaCK Hobson on 23/03/2022 12:54:11
|Thread: First Lathe - Colchester Triumph (1960s roundhead) vs Warco WM250v|
I think it is very unlikely you could ensure a high chance of detecting a knackered old lathe without personal practical experience of turning and/or tinkering on a lathe.
If you lack experience then you might not even know if the poor results you get from your lathe are due to lack of knowledge or a fault with the lathe.
Either buy new, or buy according to the direction of someone you trust and who has something to lose (if only your respect) if they give bad advice.
Big lathes are a bother to install.. but equally a bother to get rid of. If you want a big old bargain, get something smaller and cheaper to learn on.
This is stuff I have concluded after buying a few old lathes with little personal experience. I am an expert in making bad decisions; I should not be trusted to make good ones.
Machine shops will chuck big old knackered lathes in the skip just for the scrap value.
Edited By jaCK Hobson on 13/03/2022 09:06:18
|Thread: Does anyone recognise this model engine?|
I finally have better credentials for reading 'model engineer' but only as a collector. I bought this...
Pretty sure it is an engine. It has inlet an exhaust and a suggestion of a fuel pipe/carb so I guess it was intended to be IC.
I think it has twin 'cylinders' (I bet they are flat, not cylindrical) that move towards each other on an arc with a single combustion chamber in between.
I also guess it is 4 stroke as there is some backgear and cam which means the 2 valves each operate on alternate rotations.
I don't expect it would ever work... the concept would seem to require accuracy and precision well beyond that which the evidence of build quality would suggest has been achieved. But somone has invested a lot of thought and time into making it.
|Thread: It's About Time!|
As a bit or marketing, which I'm not good at, this is run by the 'South London Branch' of the BHI, which is one of the largest branches. I'm lucky to rub shoulders with world experts in their field... and there seems to be strong correlation between success and just being really nice to talk to. For pedigree, George Daniels was a founder and former president.
We had to cancel the last one because of Covid so this is a celebration of the new normal!
Free tea/coffee and cake. (No hog roast this time - a casualty of Covid )
Lots of displays that would be interesting to many on this forum. Workshop guided tour this time! I'm planning to have my 3D printer there so not just strictly horology.
I would guess this won't be as busy as last time but hopefully that gives more opportunity to 'engage', chat with exhibitors, 'have a go' etc.
Train station 50 yards away. Not far from J6 on M25. There is easy local parking for an hour or so.
|Thread: How useful is high 5000rpm spindle speed in a mill|
The DRO works. Bargain.
X is neat:
I'm a bit worried about Y - I should really turn the scale up the other way to minimise dirt getting in (for now I leave a bit of extrusion resting on top).
Does anyone want to encourage me to turn it upside down, or do some people live with a scale this way up?
Tips for installation:
I started trying to complete the install without any dismantling of the mill but it is so much easier once you do! And tapered gib strips make is simples.
Again I am glad I got this size of machine and not any bigger - the cross slide is about as heavy as I would like to handle on my own without any assistance.
Thoughts on the SX3.5
The flaking paint issue is extensive on my mill. I was forewarned so I'm managing not to let it bother me. Be careful to check if paint is going to bother you!
The X power feed installation feels like it lets the side down. The electronics and motor are fine, but the hosing is thin plastic and will not last much longer. I have had to take the cover off a few times and if you put the wrong screw in, or over tighten, then the plastic cracks and that screw hole is then no good. I got 2 screws left holding the panel on... and they come undone because I don't want to over tighten like I did the others. I thin I will be 3Dprinting a new box within 12 months. The wire to the limit switch dangles around ... not sure what the soln would be though. The power is via a separate brick about the size of an old laptop power supply, and the power input socket has its threads stripped so dangles out the box. Note that there are extensive power supply options hidden in an enclosure behind to column so a nice soltion would to have been to provide the power from there.
The column is no where near as massive as it seems in the sales pictures - most of that is a steel sheet covering to enclose the power and electronics.
The Z power lift however is a nice install. Enclosed power supply, hidden wiring etc.
The quality of finish, including surface finish, tends to be good enough and no more. An example is the gib strip. Where you might expect a scraped surface, you have the same effect but achieved with a hand held grinder. The actual points of contact are probably less than 10 across the whole gib - but these are at the extremes so it does its job. I don't know what impact this might have on wear.
The rest of the wiring and circuit boards are all neat.
As far as being a good or bad mill... I have no idea as I have nothing to compare to. But if you are buying, then be prepared for the above and you will be much more likely to avoid dissapointment.
I went ahead and cut the glass scale with a slitting disc in the angle grinder. I got lucky and it cut perfectly. I had a lot of extra scale so had the opportunity to try multiple times. Worst case was 2cm of scale chipped out at the end.
I reckon there isn't anything special about the angle grinder - I would guess that glass just shatters under stress but tends to go across scale rather than along... which makes sense from a 'science' point of view. Band saw, hack saw, just snapping without even scoring... I bet they all work within 2 cm. I was 'careful' but that is only within the limits of how careful you can be with an angle grinder.
Edited By jaCK Hobson on 27/02/2022 13:53:28
There are people on the internet who claim to have cut glass scales with methods including slitting disc in an angle grinder, metal cutting bandsaw, diamond wheels, dremmel, handsaw...
I didn't actually come across any reports of anything going badly wrong but I guess people are less motivated to publish their fails.
Some minor glitches with the mill, but I'm over that now. The box it comes in is huge and an almighty bother to move but now the mill is in place it is 'just the right size'. I have already moved its location in the workshop several times as I work out where it fits best. The Mill comes with 4 Tnuts to help fit the vice.
I took a punt on the cheapest 2 axis DRO that still had the sexy features I'll never use like radial coordinates. Just over £100 delivered due to special offer on the day from Vevor. I only gave it 50/50 that I'd receive what I expected, and that it might take months...
The DRO did come in two separate deliveries... but it all arrived in not much more than a week, and it works! Already I'm happy!.
The X axis is 1m so a bit long... I'll just take an angle grinder to it and see what happens. Not sure if I put this on the mill or the Myford... Do I need 3 axis on a mill that already has dro on spindle?
Edited By jaCK Hobson on 22/02/2022 17:12:23
|Thread: What is this?|
It has lot of little features that wouldn't help with buttons?!
|Thread: How useful is high 5000rpm spindle speed in a mill|
|Thread: What is this?|
What is this? I guess some template for drawing skirting board mouldings. Just found it in the garage (I hadn't noticed it for 20 years)
|Thread: Hermes and couriers|
Hermes may outsource so some couriers are not directly employed by Hermes.
Our Hermes delivery person is the best! Takes care and interest. Chatty if you want, or not. Waits if you are 'indisposed'.
It is very rare I have any sort of bad experience with any delivery that is the drivers fault. I owe them a lot for keeping things 'normal' during lockdown. I have never found language a problem except poor Uber eats driver who had been given the wrong address, it was dark, raining etc
I think it is great that Hermes is addressing the language challenges and trying to improve the service - I know they have a bad rep with some but that shouldn't be stuck on them if they improve. Note it works 'both ways' - there are lots of people who receive deliveries who are not fluent in spoken English.
It is probably going to be the way of the world that more people don't speak English as their first language, and that technology will really help.
I also suspect it is easy to draw misleading conclusion about 'English' speakers motivations compared to non-English. Delivery driving is probably a job where language is not as important as some other low-paid jobs (Retail springs to mind). It might be that English speakers just have more job opportunites and are distrubuted differnetly just because of that.
Edited By jaCK Hobson on 09/02/2022 09:33:59
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