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Post by Roger on Sept 12, 2019 12:29:30 GMT
Dear Roger, That sounds like a good idea. I have spent many years reading ME and even though I prefer locos, tools and clocks I still read the build aricles on road locos, stationary engines, IC engines and so on as I usually learn something as far as processes are concerned. Having spent most of my working life convincing computers to do ever more complex things, I actually enjoy using traditional manual methods almost as an antidote. Having said that I do have plans ticking over in my brain for using a stepper motor to drive the automatic feed on my hand shaper (currently it has only manual feed). Tossing up whether to use discrete logic or a PIC / Arduino. Best Regards Tim Hi Tim, Fair enough, not everyone want's to get involved with computers in the workshop. I'd really feel like my wings had been well and truly clipped if I had to go back to a manual mill. They are so restricted when all you can machine is straight lines parallel to the axes. That's an interesting project. I suppose you could use Mach3/4 as the control for the shaper, but a single line display and a rotary selector along the lines of what you have on most 3D printers would work. I do something similar with PIC projects for custom machine controls. I use a little membrane keyboard and a display connected with a serial port for the display. I've never used an Arduino because I've been able to do everything I need with the PIC. I have a general purpose PIC board I had made for this sort of thing. You're welcome to have a look at that if you're interested and I could let you have a board or two to play with if you have the ICD3 programming module.
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timo
E-xcellent poster
Completing 3 1/2 Rainhill .Building 5" Railmotor and waiting to start 3 1/2" King
Posts: 234
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Post by timo on Sept 12, 2019 14:09:33 GMT
That's an interesting project. I suppose you could use Mach3/4 as the control for the shaper, but a single line display and a rotary selector along the lines of what you have on most 3D printers would work. I do something similar with PIC projects for custom machine controls. I use a little membrane keyboard and a display connected with a serial port for the display. I've never used an Arduino because I've been able to do everything I need with the PIC. I have a general purpose PIC board I had made for this sort of thing. You're welcome to have a look at that if you're interested and I could let you have a board or two to play with if you have the ICD3 programming module. Dear Roger,
Thank you for your kind offer. Once I have decided which direction to go I might take you up on that. At the moment I am tending towards discrete logic as I will only need 3 or 4 different feed rates. A simple selector switch which chooses four different pulse counts plus a left / right switch and a standard H mode driver module would suffice. I tend for historical reasons to use assembler on the PIC (plus a bit of Pascal as I have a compiler) and C on the Arduino. I have a cut down Arduino circuit with a crystal and about 5 other components to act as a stand-alone module but perfboard each one up as I haven't got around to laying up and getting boards made - something I must do! I have three different PIC dev systems including an IDC3 and of course for Arduino all you need is a Uno board plus the free software. I do like the Arduino IDE - easier to use than the PIC equivalents.
I guess I ought to start a thread on this rather than cluttering up your Speedy thread.
Best Regards
Tim
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Post by terrier060 on Sept 12, 2019 18:42:46 GMT
Yes Roger, we were once the young folk and we started before the age of computers. Old folk like us are gradually dying and being replaced by a new breed who will take up these new ideas and methods. Progressive model engineers like yourself and others on this Forum are leading the way and the dinosaurs are gradually dying out!
Having said that I remain Imperial, mainly because Terriers were all Imperial, as are the antique clocks that I restore. When you research a lot of clocks you recognise repeat dimensions which would be meaningless in metric. For example the dimensions of clock plates are often about 5.25 inches by 6 to 8 inches. Ed
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Post by Roger on Sept 12, 2019 19:30:07 GMT
Yes Roger, we were once the young folk and we started before the age of computers. Old folk like us are gradually dying and being replaced by a new breed who will take up these new ideas and methods. Progressive model engineers like yourself and others on this Forum are leading the way and the dinosaurs are gradually dying out! Having said that I remain Imperial, mainly because Terriers were all Imperial, as are the antique clocks that I restore. When you research a lot of clocks you recognise repeat dimensions which would be meaningless in metric. For example the dimensions of clock plates are often about 5.25 inches by 6 to 8 inches. Ed Hi Ed, All true, but I'm 61 and was taught the Metric system back in secondary school, used old and new units in my apprenticeship and pursuaded the company I worked for to make the change. There were many just like me doing the same in industry yet none of this seems to have filtered down to ME circles. I think this is because the older generation of MEs are always in charge, and they were retired when I was at school. There's a tremendous resistance to change in ME, especially since the subject matter is ancient and there's a long history of old methods and old designs. Hopefully this thread will help open some eyes of the old and give hope to the young.
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Post by ettingtonliam on Sept 12, 2019 19:58:44 GMT
I'm 69, and it was imperial measure at school, though metric measures were coming in in chemistry and physics. The construction industry had gone metric by the time I started work in 1971, so all my working life has been spent using metric measurements, except restoration projects which were imperial. At home, I work in imperial, largely because the drawings I'm working off are imperial. I do have imperial and metric cutting equipment about in equal quantities, though I've got a lot more imperial micrometers than metric. It isn't difficult to be bilingual in measurement terms, and I don't understand those who won't.
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timo
E-xcellent poster
Completing 3 1/2 Rainhill .Building 5" Railmotor and waiting to start 3 1/2" King
Posts: 234
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Post by timo on Sept 12, 2019 20:16:13 GMT
I think that part of the issue is that there are very few loco designs dimensioned in metric compared to those in imperial. Likewise a lot of the imperial designs are actually dimensined in fractions..... I personally prefer imperial but can work in either - digital measuring instruments sort that out. Until I get DRO on the Myford S7 turning is done in imperial, the mill has 3 axis DRO so can work in either and the shaper only has divisions without numbers on the downfeed! I do have both metric and imperial files though
Tim
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Post by Roger on Sept 12, 2019 20:24:32 GMT
I think that part of the issue is that there are very few loco designs dimensioned in metric compared to those in imperial. Likewise a lot of the imperial designs are actually dimensined in fractions..... I personally prefer imperial but can work in either - digital measuring instruments sort that out. Until I get DRO on the Myford S7 turning is done in imperial, the mill has 3 axis DRO so can work in either and the shaper only has divisions without numbers on the downfeed! I do have both metric and imperial files though
Tim
Hi Tim, I've worked exclusively for so long in Metric that I don't think in Imperial any more. All of my machines are Metric and I convert anything imperial into Metric units. Personally I find it much easier than using fractions which don't immediately tell you if one size is larger than another, or worse still, a mix of fractions and decimal inches. It's the complete mess when it comes to imperial threads that I find the most frustrating, ME adding their own confusion into the heady mix! Still, each to their own, I'm just glad I don't have to use them.
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Post by andyhigham on Sept 12, 2019 21:07:47 GMT
There is no difference working in metric or imperial, it is only the base that is different. The real t**t is the fractions that litter drawings, no micrometer, vernier caliper or DRO will read fractions.
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Post by terrier060 on Sept 12, 2019 21:51:57 GMT
The classic is timberwhich is still measured in Imperial and metric on the same piece! I work in either, mainly because it is easier to get materials in metric now, As all my machines are Imperial it is easier for me to use imperial decimal measurements, but the Tormach just works fine whatever you use as long as the drawings are correct! No more marking out with marking blue and squinting with poor eyesight! I have written a program which instantly converts my fractional dimensions into decimal so there is no problem
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Post by Roger on Sept 13, 2019 11:40:50 GMT
Back to the blower arrangement to catch up with what's been going on in the background... Here's a quick reminder of the general arrangement of the prototype. I decided that I was still thinking way too much along conventional manufacturing lines for the finished item. The thin red coloured motor shell is fine in metal, but not that strong in plastic. Also there would be three major parts that needed to be assembled and bonded together. Sectioned assembly by Timothy Froud, on Flickr So I decided to be more radical and beef the whole thing up and print the body in one piece. Remember that making something chunky doesn't add much weight because the inside is only 15% filled in this case. It does make a huge difference to the overall strength of the print though. That poses some challenges if you want to avoid it being covered in support material. Normally that isn't a huge issue, but I'm using ColorFabb HT high temperature filament which tends to make those difficult to remove and leaves unsightly marks where they've been broken away. So I altered the end so that it had a large flat area that could be printed from, leaving sloping sides to the two smaller diameters which then wouldn't need any supports. The two tubes do need internal supports though, so I used a cylinder enforcer in the slicer inside those two to make it create supports in that area. The air inlet slots half way along the sides had generous 45 degree chamfers added to them so they could be printed more easily. That not only deduces the amount the printer had to bridge without supports, but also made it a lot stronger. So here it is after a 16 hour print. I used a 0.15mm layer height so that the diameters were well defined. 20190912_094609 by Timothy Froud, on Flickr Even so, the inside was scruffy when the support material was removed, and the diameter was under size even though that worked out just fine when printed in the other orienation as a separate part. So here I've turned a support for the part that's in the vice so it doesn't get crushed and nipped it up as lightly as I think I'll get away with. Then it was a matter of using very light cuts and only 1mm deep with a razor sharp cutter to gingerly bring it out so it was a nice fit. I could have used a file, but you know what I'm like! I ought to have made the support go up to the top and engage in the bottom of the top section too. That would have made it a lot more rigid. Still, it worked out ok with a little patience. 20190912_140007 by Timothy Froud, on Flickr The end plate was designed with the sleeved grommet off centre to miss the shaft boss. I also created two shallow 'U' shaped closed channels to act as strain relief and to keep the wires tidy. This kind of arrangement is used on the 3D printer to thread cable ties through so that it stays together during assembly. You'd never design something like that, even for casting, it would be madness for anything other than a 3D print. The trick with this game is working to the strengths of the process rather than adapting design ideas you used in conventional ones. 20190913_102911 by Timothy Froud, on Flickr Anyway, the ends are now screwed on with 3 x M2 screws and it's ready for action. I'll be giving it a try on my neighbour's American locomotive this afternoon since he wants to run that up to test the rolling road he's just modified. 20190913_121626 by Timothy Froud, on Flickr
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timo
E-xcellent poster
Completing 3 1/2 Rainhill .Building 5" Railmotor and waiting to start 3 1/2" King
Posts: 234
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Post by timo on Sept 13, 2019 14:59:35 GMT
Roger,
That looks good. The print quality is impressive. 16 hours print time - yikes - you hope at the end of that that it is all OK! I had a Prusia 3D printer but sold it as I wasn't making any use of it - good kit. Interesting extruder on yours.
Tim
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Post by Roger on Sept 13, 2019 18:15:40 GMT
Roger, That looks good. The print quality is impressive. 16 hours print time - yikes - you hope at the end of that that it is all OK! I had a Prusia 3D printer but sold it as I wasn't making any use of it - good kit. Interesting extruder on yours. Tim I've still got lots of things I want to make with the printer, mostly things around the workshop to keep things tidy.I just love the fact that you can create something with so little effort. I downloaded an apple picker from thingiverse and printed that out so I could go scrumping today. I've bought several different types of filament too experiment with. All good fun.
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Post by andyhigham on Sept 13, 2019 18:48:41 GMT
The residential home my mother will be going to next week has an apple tree worth scrumping, huge delicious looking Bramleys
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Post by Roger on Sept 13, 2019 21:01:37 GMT
Back to the water selection and bypass valves... This is the Steel fixture to hold the parts the other way round so I can machine the 'O' ring pocket and the 3mm bore for the shaft. I've taken a lot of care to completely remove any burrs since I want this to sit really flat against the face. 20190913_110518 by Timothy Froud, on Flickr I've reamed the 3mm hole in this and also in the fixture because I made a mistake with the diameter of one of these and it won't fit the body. That's a problem because I can't machine the diameter with those fixing screws in the way. I only need to take off 40 microns. 20190913_164108 by Timothy Froud, on Flickr So I've cut of a short length of 3mm Silver Steel to guarantee that the middle is true to the outside even when the fixing screws have been removed. Then the live centre was used to press the part into the fixture so I could machine it. The parting tool was ground to make sure that only the LH side touched. 20190913_172155 by Timothy Froud, on Flickr Anyway, that worked out nicely and they both fit now. 20190913_215105 by Timothy Froud, on Flickr
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Post by Roger on Sept 14, 2019 21:22:26 GMT
Time to make all of the arms and levers for the two valves. This is one of the ones connected to the valve shaft with a hex drive. The shaft is 3mm diameter, but using a hexagon instead of a square it's possible to have 2.7mm across the flats and a 0.5mm corner radius. That's been chosen so I can machine the hex with a 1mm cutter. 20190914_130321 by Timothy Froud, on Flickr The shaft was tested to make sure it was a good fit. 20190914_130331 by Timothy Froud, on Flickr The tilting rotary table was tipped over and the 1.5mm slot for the link was mathined with a 1.5mm diameter cutter following a single line along the side of the slot. 20190914_144343 by Timothy Froud, on Flickr One of the longer arms was machined from 40mm diameter free cutting Mild Steel bar. Here's a wobbly video of it being parted off as usual using power feed, proof if ever it was needed that Carbide Inserts are perfectly at home with intermittent cuts, contrary to what you might have been told! 20190914_190505 by Timothy Froud, on Flickr This is how they look, about 0.1mm too wide. I'm not overly bothered if it's not perfectly to size, it just needs to be nicely finished. 20190914_205950 by Timothy Froud, on Flickr You always get cutter bounce from side to side when parting off with intermittent cuts like this. This sort of thing is a pain to hold in the vise, so I've used some Florist's wire to stop if moving down when I'm filing it. 20190914_215306 by Timothy Froud, on Flickr The long arm still needs the slot in the end, but otherwise it's finished. 20190914_220517 by Timothy Froud, on Flickr
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timo
E-xcellent poster
Completing 3 1/2 Rainhill .Building 5" Railmotor and waiting to start 3 1/2" King
Posts: 234
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Post by timo on Sept 15, 2019 7:57:08 GMT
Roger,
The bits look good.
Were you using straight cutting oil to part off? What oil do you use?
Best Regards
Tim
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Post by Roger on Sept 15, 2019 8:37:35 GMT
Roger, The bits look good. Were you using straight cutting oil to part off? What oil do you use? Best Regards Tim Hi Tim, I'm using neat EXOL EXCELCUT 427 from eBay. It works really well, but you have to make sure the return path to the pump doesn't have a fine gauze or the tray will fill with oil. It's more messy than suds where you can tolerate the odd splash on the floor, so you have to make sure your splash guarding is good. I really like it though, I wouldn't go back to suds because this seems to work much better.
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Post by Roger on Sept 15, 2019 21:44:01 GMT
A few odds and ends being moved further on today... This is the arm that goes on the end of the long rod from the cab that's turned to operate the bypass valve. It's going to be permanently pinned to the shaft. 20190915_103145 by Timothy Froud, on Flickr And this is the arm on the other side that moves back and forth to operate the axle pump mixing valve. The joggle is so that the long actuating rod can be as straight as possible. The final thickness is 5mm so it makes sense to use 5mm BMS for that. The edge profile is done first... 20190915_113823 by Timothy Froud, on Flickr ... including the 1.5mm wide slot. You can see that I've taken a cut across the top at the slotted end so that the 1.5mm end mill will reach down far enough. 20190915_121605 by Timothy Froud, on Flickr Then it's turned onto its side and the holes drilled and reamed before the profile is carefully machined leaving 1mm at the bottom so it stays attached. 20190915_144050 by Timothy Froud, on Flickr 20190915_154310 by Timothy Froud, on Flickr It's left a massive burr for some reason, but that will come off easily enough with a needle file. 20190915_174829 by Timothy Froud, on Flickr The link that turns the rotary motion back into a linear vertical motion for the mixing valve is seen here getting the slot added. 20190915_123826 by Timothy Froud, on Flickr 20190915_140925 by Timothy Froud, on Flickr I've machined the diameter and the bore of the valve element from Fluorosint since I've got loads of it and it's a superior material to PTFE. I might regret doing it in this order though. I've turned the other end over size so that the cross hole can be machined before turning the outside diameter. I think on balance that's a better way to get a clean cut around the drilled holes. We'll see. It's easy enough to make another one. 20190915_144607 by Timothy Froud, on Flickr
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Post by delaplume on Sept 16, 2019 13:04:48 GMT
Back to the blower arrangement to catch up with what's been going on in the background... Here's a quick reminder of the general arrangement of the prototype. I decided that I was still thinking way too much along conventional manufacturing lines for the finished item. The thin red coloured motor shell is fine in metal, but not that strong in plastic. Also there would be three major parts that needed to be assembled and bonded together. Sectioned assembly by Timothy Froud, on Flickr So I decided to be more radical and beef the whole thing up and print the body in one piece. Remember that making something chunky doesn't add much weight because the inside is only 15% filled in this case. It does make a huge difference to the overall strength of the print though. That poses some challenges if you want to avoid it being covered in support material. Normally that isn't a huge issue, but I'm using ColorFabb HT high temperature filament which tends to make those difficult to remove and leaves unsightly marks where they've been broken away. So I altered the end so that it had a large flat area that could be printed from, leaving sloping sides to the two smaller diameters which then wouldn't need any supports. The two tubes do need internal supports though, so I used a cylinder enforcer in the slicer inside those two to make it create supports in that area. The air inlet slots half way along the sides had generous 45 degree chamfers added to them so they could be printed more easily. That not only deduces the amount the printer had to bridge without supports, but also made it a lot stronger. So here it is after a 16 hour print. I used a 0.15mm layer height so that the diameters were well defined. 20190912_094609 by Timothy Froud, on Flickr Even so, the inside was scruffy when the support material was removed, and the diameter was under size even though that worked out just fine when printed in the other orienation as a separate part. So here I've turned a support for the part that's in the vice so it doesn't get crushed and nipped it up as lightly as I think I'll get away with. Then it was a matter of using very light cuts and only 1mm deep with a razor sharp cutter to gingerly bring it out so it was a nice fit. I could have used a file, but you know what I'm like! I ought to have made the support go up to the top and engage in the bottom of the top section too. That would have made it a lot more rigid. Still, it worked out ok with a little patience. 20190912_140007 by Timothy Froud, on Flickr The end plate was designed with the sleeved grommet off centre to miss the shaft boss. I also created two shallow 'U' shaped closed channels to act as strain relief and to keep the wires tidy. This kind of arrangement is used on the 3D printer to thread cable ties through so that it stays together during assembly. You'd never design something like that, even for casting, it would be madness for anything other than a 3D print. The trick with this game is working to the strengths of the process rather than adapting design ideas you used in conventional ones. 20190913_102911 by Timothy Froud, on Flickr Anyway, the ends are now screwed on with 3 x M2 screws and it's ready for action. I'll be giving it a try on my neighbour's American locomotive this afternoon since he wants to run that up to test the rolling road he's just modified. 20190913_121626 by Timothy Froud, on Flickr Hi Roger, As usual very impressive stuff-----------------though I can't help thinking we've been down this road before, sort of ?? LoL !!}--------- en.wikipedia.org/wiki/V-3_cannon
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Post by Roger on Sept 16, 2019 21:38:20 GMT
Not much achieved today due to a round of Golf! I did finish this off though... 20190916_213656 by Timothy Froud, on Flickr ... and profiled the drop links that operate the two valves. These are made from 1.5mm thick gauge plate so they can be relatively slender but still strong. There shouldn't be any large forces involved in operating the valves. 20190916_213634 by Timothy Froud, on Flickr
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