Here is a list of all the postings Zan has made in our forums. Click on a thread name to jump to the thread.
|Thread: Any advice on how to cut/file a 45 degree chamfer on a 1mm steel sheet to EXACTLY 45 degrees?|
Come on Jeff, get real He has very little kit and no room for even a small mill let alone a surface grinder He is asking for advice. Not a scathing unhelpful comment from someone who obviously has a lot of kit
|Thread: Plumbing Overflow - Help!|
Lol been there done that ( almost)
|Thread: Bandsaw overhang|
Good solution John, but I went a bit further. As the outboard platform is wider on my version, I bolted a piece of angle about 2” long there almost touching the fixed jaw . This allows a g clamp to hold very short pieces rigid It is only ever removed and reset when a rare angled cut is needed. It could still be fixed to your lower insert bar. The advantage of this is that it supports the work and removes the twisting caused by the cutting action, thus making it easier on the vice.
|Thread: A Certain Age|
I came on here today to read a particular thread, but having read all this great funny one. Iv forgotten what it was......
I was always taught never start a sentence with “and”....... or am I the dolly old duffer?
Edited By Zan on 10/03/2021 13:42:41
|Thread: A Cornish conundrum|
A photo would help
|Thread: SX2P Gas Strut Modification Issue?|
rod Interesting! Just checked my junk box there’s a lot of interfaces in the system
1 the rack and pinion are well clear in their respective spaces, but the bottom of the pinion grooves seem to be rounded and could be causing interference.
2 the universal joint has about 0.04mm slack
3 the worm shaft can move in and out due to clearance prob 0.04mm
4 fit between worm and wheel ? Can’t determine
5 the dog clutch between wheel and pinion shaft 0.25mm?
6 clearance between rack and pinion unknown but it must be there.
conclusion A lot of interfaces all of which need clearance to work or clever expensive engineering to eliminate all contributing to the backlash . This makes me even more certain a z feed screw of some type is the way forward and ditch the gas strut and spring system as I did I never lock the z , not a good idea anyway with cnc. I have to use light cuts , nothing like Jason in his blogs, but the results are excellent and well worth the effort of converting the machine
interesting. The rack is 25 wide. Why did they go to the expense of making the pinion gear 75 long? A bit of a waste the end could be reduced to below root dia and a bush inserted to reduce the hole diameter, or use a reduced hole..which to me seems cheaper. I wonder???
Edited By Zan on 05/03/2021 11:29:37
edit. Autotype errors
Edited By Zan on 05/03/2021 11:37:54
If your fine adjustment does nothing when adding cut, then the head drops 5 mm then the rack /pinion interface is strange,. Perhaps the pinion is moving in its bore The sx2 is a cheap light weight machine. Built to keep the costing down. When I converted mine to cnc I found that the z head dovetail casting was warped, probably from machining it when the casting was a bit green. It took a lot of work to get it so that with the column off the machine the head could slide up and down without any twisting. The test was done with a 3/4” silver steel bar in an R8 collet and the head was pushed along the column by hand. I can see that this could be a source of your problems as well.
I think the twisted casting was causing it to rock and this would be a course of the sticking. I found it by putting the head on the surface plate on the working face of the dovetail. From memory it I think needed about 15 thou packing under one corner to stop the rocking.
the idea that a ball screw nut will allow the head to fall is bunkum. The nut has to rotate for it to move! Fitting any z feed screw would solve the problem as you will have total feed control and sticking issues will be resolved unless there is serious clearance issues within the z slide arrangements as I had . Fitting a motor to any feed screw would make positioning impossible without the associated electronics and/or computer control. A hard wheel would do the trick nicely, so you end up with an arrangement as in one of the photos above and like the down feed arrangement on the Emco FB2 mill
I could never understand the original spring arrangement as the lever arm resulted in a change of upward force as the head is moved up and down all this and the z feed system was scrapped In my conversion which works very very well without any form of upward thrust. When jogging up and down with Mach 3 I need 1-4 x 0.01 increments in order to obtain a reversal of the head movement . This has not manifested itself as any problem while in use.
fit a full feed screw and dump all the z feed arrangements which I always considered to have too much lag and interface clearances to be effective. Your problems seem to confirm this
Edited By Zan on 05/03/2021 10:06:29
|Thread: Condenser Cooling water flow|
Yes hopper. I did make gunpowder!
no Duncan the condenser is there to provide a vacuum to give a greater pressure difference, and to reduce the sink temperature of the engine as much as possible
Regarding condensate temperature, thermal efficiency is all about temperature difference, the hotter the hot source (T1) and cold sink (T2) difference the greater the efficiency so a cold condensate means a bigger temp difference and therefore More efficiency.
Maximum theoretical efficiency = (T1-T2)\ T1. %. Measured in degrees Kelvin
if one considered only the engine efficiency itself and take the boiler heat source out of the equation, steam tables show that a tremendous increase in pressure is needed to increase temperature, and of course that brings lubrication problems associated with reciprocating engines. Remember all early steam engines were powered by the vacuum in the condenser, not the steam pressure
Stumpf in his treatise of the “Unaflow Engine” had a simple maxim “ Keep the hot end hot and the cold end cold” amazingly, his cylinders were cooled in the centre where the exhaust is, and that caused expansion problems resulting in the cylinder needing to be bored barrel shape. so the smaller dia hot ends expand more and result in a parallel bore. This was achieved by reversing the process, the normally water cooled centre jacket was fed with steam while the hot end steam jacket was water cooled thus reversing what is found when the engine is running. His other important aspect by the way was to keep piston end clearance very very small , just a few thou carefully calculated in relation to the overall expansion of cylinder and piston systems.
one of the many reasons aircraft fly so high is because of the air temp being lower results in a lower cold sink. This also enables greater cooling of the turbine blades which run an a higher temperature fluid than their melting point
Edited By Zan on 24/02/2021 10:41:11
Edited By Zan on 24/02/2021 10:44:09
I found about this out as a 10 year old with a love of chemistry! The local chemist gave me a glass condenser, which was duly set up to make distilled water with the cold initially going in the top. Result, steam not distilled water flowed out the bottom. Very disappointed I cursed (sulk), then had a think, switched the water input to the bottom n bingo it worked. By the way I set my wooden retort stand on fire, I used a mammon burner for heating
easy reasoning. With the cold water in at the top, it hit the hot steam at the top, it also got hot, therefore cannot cool at the bottom. If. It goes in at the bottom, it will rise being forced to the top getting hotter all the time, but will always be less than the steam. So the bottom where the steam is coolest, get the biggest temp drop with the cold water input. At the top, the cooling water although hot by now is still lower than the steam input
so in at the bottom, out at the top very logical when you think about it
Edited By Zan on 23/02/2021 22:33:17
edit. Dont you hate auto type
Edited By Zan on 23/02/2021 22:34:38
|Thread: Using a vfd for two machines|
V d f thin on the ground? There’s thousands for sale Google it. Not worth the risk of disconnecting whithout. Switching the mains off and destroying the vdf Get one for each machine. I have one on each of my 5 machines they all have different perimeters set to suit the individual requirements. They are cheap( ish) compared with the uncertainty of remembering to change the settings n plugeps. What happens when one machine is running very slowly and you want to run another at the same time?
StrangeG double post without the edit! See below
Edited By Zan on 21/02/2021 00:04:32
|Thread: Confusing t-slot dimensions|
Ps you need good clearance with t nuts, so decimal mm dimensions for them come with the fairies
You got a machine, so mill t slot nuts to suit each one Using nuts in place of proper t nuts will give you grief in the long term. Make them, it would take less time than typing your post.....
all my 4 millers which I have had had different sizes. First task with each new machine was to mill sone new ones...
Edited By Zan on 20/02/2021 23:55:21
|Thread: Should it be bent? Meddings Content|
Meddings would not paint their motors a different colour to the drill, and it’s mounting is strange. The pulleys should align and not be so far out vertically which will cause wear and noise levels
I think this is a bigger problem than the bent arms, which can be corrected with “ washers” under the motor mounting bolts
|Thread: Skynet is Coming|
too many devices are becoming so called smart
why would you want a phone app to control a toilet flush.. not nice later handling a contaminated device.....
do what you can to disable the wifi, the pw protection on them is usually poor and it gives opportunities for hackers to get into your systems
My dishwasher annoys me, we only use one program but it has to be selected with three button ( extreme left, centre then extreme right ) presses not one if you hit the wrong button in the centre the so called eco program runs for 3.5 hours not our normal 29 min......
my camper van control unit had only three buttons one to cycle through then select with another then back to the first to cycle through the changes you need. So frustrating when you miss the thing u want. It failed, repaired, failed replacement costs £300 . So I , ripped it out n replaced it with switches
Edited By Zan on 20/02/2021 09:59:00
|Thread: Newton Tesla Electric Drives|
Perhaps off topic, but regarding single phase noise and problems.
Interesting! But it all depends on the s phase motor. When I got my new s7 in 82 I had to get a motor, and as I had already broken the bank I opted for a cheaper foot mount roped motor. It was TERRIBLE! The chatter and vibration marks made the new machine a real pug. I took it back n got a Brook Crompton redial the mount. Oh what joy! Super smooth, and used until I managed to get a cheap vdf in about 98
|Thread: Machining a kurt clone vice|
Well done, a good solution
|Thread: ml10 or some other?|
I have been very happy with my s7 new in 82, but then I had to add a gearbox and even then a motor!
looking at the specs for the Warco, it looks a better machine with a better bed guide system, full gearbox and screwcutting, enabling a range of sliding feeds as well . What is good is the spindle bore, the 9/16 on my Myford was a constant annoyance until I got a cheap Colchester student 15 years ago( not much used!)Buying the Warco would give you about £300 to spend on other stuff.
the speed 10 looks a good machine with its stand and the tool range is ok but not brilliant the vertical slide is shop built and looks as if it lacks rigidity in the mounting You won’t get a lot of use from the studies. The cutting tools could be good or v poor, some stuff I looked at when considering the Myford were to say the least a bit sad.
Edited By Zan on 19/02/2021 13:14:08
Edited By Zan on 19/02/2021 13:15:34
|Thread: You think you have trouble starting your car on a cold morning?|
Gee you can’t get decent coal these days I wonder where it came from?👻
|Thread: Further Adventures with the Sieg KX3 & KX1|
Interesting stuff Jason, always fascinating to see your efforts , you are teaching us all so much with your experience. Keep it coming!
how exactly did you align each side of the flywheel when flipping it over? I’m intending to do something similar, and considered a pin in the central bore then another removable one to mate with one face of the 1” dia holes you produced
did you use the “ tool stay down” feature ( can’t remember the exact wording} when doing the initial adaptive clearance?
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