Author Topic: Replacement Knobs, Feet and Fittings for Test Equipment  (Read 466808 times)

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Online beanflyingTopic starter

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #25 on: March 10, 2019, 07:30:54 am »
That will teach me for not reviewing the GCode before printing.  :palm: Result was exactly what it miscalculated.

Oddball Sli3er Prusa issue with the small flutes I guess.
« Last Edit: March 10, 2019, 07:32:56 am by beanflying »
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #26 on: March 11, 2019, 12:04:59 am »
Random idea for the HP knobs to make a better clone. Standard Hardware store Cup Washer (11mm OD 4mm bore) reworked to make a replacement metal trim for the knob. Would require a female form to round the edge over on but a correct thickness peice of steel  (1.5mm) with a hole drilled in it then peen the lip over then finish as required with a Dremel/Files etc.

In an ideal world you would make a proper tool for stamping/punching them out but this might suit for a one off home option.

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #27 on: March 11, 2019, 12:32:32 am »
Random idea for the HP knobs to make a better clone. Standard Hardware store Cup Washer (11mm OD 4mm bore) reworked to make a replacement metal trim for the knob. Would require a female form to round the edge over on but a correct thickness peice of steel  (1.5mm) with a hole drilled in it then peen the lip over then finish as required with a Dremel/Files etc.

In an ideal world you would make a proper tool for stamping/punching them out but this might suit for a one off home option.
Investigate plastic joinery buttons used for hiding screw heads for capping the knobs.
Some have a spigot that inserts into Robinson (square drive) screws.
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Offline bitseeker

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #28 on: March 11, 2019, 04:13:09 am »
Great thread, bean. Here are all my bookmarks for a variety of parts on Thingiverse.

HPAK
Bonus (not a spare part):
Wall mount for HPAK DMMs with IR interface: https://www.thingiverse.com/thing:1056579

Keithley
Fluke 
Valhalla 
Racal-Dana
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Online beanflyingTopic starter

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #29 on: March 11, 2019, 06:23:30 am »
Thanks @Bitseeker will add yours later in the evening.

Bizarre thing with the HP Knob reduced the export quality from Fusion into sli3er PE and the Spaghetti Monster from yesterday went away seems I overloaded it's brain :-//

Still not 100% done but this one is dimensionally close to the real deal if anyone wants to print it and take a look. This one will take the HP Brass insert with a little heat to slide it in and the grubscrews protruding into the alignment slots I have put in the design so the holes line up while you do that. Switch off thin wall detection and print at 0.1 should get a result.

Edit of the Edit of the Edit - ZIP now removed. Updated Zips further down this thread or found in the Index under HP Knobs.
« Last Edit: March 14, 2019, 05:26:29 am by beanflying »
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #30 on: March 12, 2019, 02:37:12 am »
Eight other colours but no Grey and a non bright Green time to add more Filament to the stash :palm:

I have sorted out the high quality STL spaghetti issue but the file goes over the 1Mb allowed here. When I have a set including a Cap I will put them on my Google Drive and link them with a separate post.

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Offline DaJMasta

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #31 on: March 12, 2019, 03:13:34 am »
Here's a potentially useful one for the generic fittings category: a set of anti-vibration gaskets for common computer fans
https://www.thingiverse.com/thing:3486100
Have one that fit 40mm, 60mm, 70mm, 80mm, 92mm, and 120mm fans (was really easy to adjust dimensions on the sketch to crank all of them out), and they've been printed and test fit and the dimensions seem good.  Worth noting that this will only be useful for printers that can print flexible filaments, and the more flexible the filament, the better the anti-vibration performance, but a lot of printers can do TPU or similar, so they may help quiet down your fans without having to go buy a bunch of gaskets which tend to be a little overpriced imo.
 
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #32 on: March 12, 2019, 03:45:14 am »
so are you going to keep posting on how you improve gcode on agilent knob in this thread? go post the gcode in thingyverse, most people post stl there.
this msg will self destruct

I choose not to give my files to Thingiverse for a start and am unlikely to change my mind on that in the future. The files I choose to put up here are mine and available for any non commercial use including by stl hosting sites for their gain. Depending on the item and the complexity of the Print I tend to also post the Cad file so others can tweak it if required and also encourage others to have a go at CAD for their own.

As we all have different Slicers and Printers in use the best option is to give any Print Specific settings you think relevant to a particular STL. The Knob for example varies from 'my normal' PLA settings by using 0.1mm Layer and turning off 'Detect Thin Wall' and 'Avoid Crossing Perimeter' with no supports. These two were the principal cause of the Spaghetti.

I am sure these will have similar variations in other Slicers but I don't use anything else and have only really glanced Cura and Ideamaker but never used them seriously to know what settings are or are not available.
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Offline Mechatrommer

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #33 on: March 12, 2019, 04:45:05 am »
Quote
I choose not to give my files to Thingiverse for a start and am unlikely to change my mind on that in the future. The files I choose to put up here are mine and available for any non commercial use including by stl hosting sites for their gain..

Thingyverse has common attr + Non commercial license, but what stopping others from downloading your model, mod it and repost on in their domain? with different licensing scheme?  like some of your links in op? Same Thing if you post your model here.. but i was not talking about your attached model, i was talking the process you are trying to achieve in few of your latest posts.
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Online beanflyingTopic starter

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #34 on: March 12, 2019, 05:11:47 am »
Thingiverse - Makerbot - Strtasys get the support they have earned over time. Not very much at all :horse: It took a major public stink only a few years ago for Thingiverse to adopt their 'current' legal waffle 'subject to change'. As to their parents companies :bullshit: over time that is best left for another forum or thread. Basically I don't have any trust in them based on their combined history.

Here my files are offered by me and are here at my discretion and are offered under 'my rules' such as IP 'borrowing' for gain happens. There is some of my commercial and business print work that won't be as that is my D&C and IP to make money from. If others try openly to make $ from using them them at minimum they can expect a public flogging for IP theft and most likely me pursuing them to cease if they go down the evilbay path to resell. These low volume speciality designs and reimaginings for old test gear are unlikely to attract any serious commercial entity and more likely to be someone running a backyard printfarm using stolen designs because they have no clue or imagination to create their own. One example https://3dprint.com/120727/ebay-licensing-3d-models/

Process of what is put here to accomplish a good result as per the last post it is offered openly along with help on settings within the understanding that all Slicers and Printers are different. Feedback or suggestions on how a design could be improved should be welcome too as this is to benefit all in need of unobtanium.

In the case of the last few posts in particular if anyone had an idea on how to treat the top cap and washer I was throwing it out there for other ideas that may be better than mine.
« Last Edit: March 12, 2019, 05:23:45 am by beanflying »
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Offline coppercone2

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #35 on: March 12, 2019, 05:21:20 am »
lol i just put wooden bits

their like battle scared pirates
 

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #36 on: March 12, 2019, 05:56:40 am »
THANKS. I have been looking for a tektronix foot since forever :)
 

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #37 on: March 12, 2019, 06:10:18 am »
THANKS. I have been looking for a tektronix foot since forever :)

Cast a glance in the TEA thread (if you dare  ;D ) https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg2262690/#msg2262690 and the few follow up posts after the link regarding print orientation and materials. Basically stand it on the small part of the foot with supports for improved strength and allow the bolt to keep the layers together. Also Nylon, PETG or maybe ABS rather than PLA IMO in order of toughness.
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #38 on: March 13, 2019, 06:54:32 am »
HP Knob 1/4" plain shaft, washer and Cap to suit reuse of the Stock Brass bush is at the Google Drive Link STL's along with the Fusion 360 CAD file. https://drive.google.com/open?id=16TDa7CEWRLShBq6--NWDScFT7Y22YXop

I still need to drop a 0.2mm Nozzle onto most likely my CR-10S/Glass Bed when I get the correct colour filaments in for a finished item. That said the samples in the photo came of my Ender Pro with a 0.4mm Nozzle and are physically great and cosmetically not horrid. The surface finish on the cap is due to a worn bed. Personally this entire job would suit SLA better than FDM.

FDM Print Guide - 0.1 Layers, PLA, No supports, Turn off detect thin walls in sli3er (or look for a similar setting in your slicer) to stop the Spaghetti from a few posts back.

The Washer is virtually unprintable with a 0.4mm Nozzle but the Cap print holds nicely without it into the printed Knob with or without it. A quick wipe with a paint marker could be done. as shown too.

Brass insert use a fat tip on a soldering iron set to 200'ish C with firm pressure. Make sure the allen screws are protruding slightly into the guide slots so the final position is correct.

For improved overall look most likely replace the lot on each bit of test gear as needed and sell the other unobtanium to fund more TEA  ;)
« Last Edit: March 13, 2019, 11:35:56 am by beanflying »
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #39 on: March 13, 2019, 12:20:37 pm »
Here's one for you:
HP 5040-7829 cord wrap foot, fits HP174* CRO's.

Thingiverse was useless and Google too.  :horse:

I've had a couple of these fine old CRO's both with missing feet on the back and as there's BNC's, a fuse holder and the CRT cover plate protruding, none of which make a stable foot to stand/store the scope.  ::)

Little project for someone with a sample to build a 3D model.
Drilled broom handle offcuts look a bit shit.
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #40 on: March 13, 2019, 04:29:11 pm »
I've been working on the old style HP feet. Part number 5060-0767.
Still have to work out how to make the spring-loaded retaining pin, probably using an M3 cap screw, spring and nut or something.
Where does all this test equipment keep coming from?!?

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #41 on: March 14, 2019, 12:21:41 am »
I've been working on the old style HP feet. Part number 5060-0767.
Still have to work out how to make the spring-loaded retaining pin, probably using an M3 cap screw, spring and nut or something.

You can fairly easily buy Flat Head Rivets in all sorts of lengths and diameters if you want to keep it more like the original. Try a Google search for "3mm flat head aluminium rivets" The 3x5mm collar and spring should be easy to sort out.

The few older Nixie Counters I have with those feet came with all attached  ;D But keep on with the design  :-+

Here's one for you:
HP 5040-7829 cord wrap foot, fits HP174* CRO's.

Thingiverse was useless and Google too.  :horse:

I've had a couple of these fine old CRO's both with missing feet on the back and as there's BNC's, a fuse holder and the CRT cover plate protruding, none of which make a stable foot to stand/store the scope.  ::)

Little project for someone with a sample to build a 3D model.
Drilled broom handle offcuts look a bit shit.


Send me one of the Scope's and I will send you some feet back in exchange :-DD Drop a picture of the foot here so we can have a look at if it is printable for a start?
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #42 on: March 14, 2019, 12:42:11 am »
Here's one for you:
HP 5040-7829 cord wrap foot, fits HP174* CRO's.

Thingiverse was useless and Google too.  :horse:

I've had a couple of these fine old CRO's both with missing feet on the back and as there's BNC's, a fuse holder and the CRT cover plate protruding, none of which make a stable foot to stand/store the scope.  ::)

Little project for someone with a sample to build a 3D model.
Drilled broom handle offcuts look a bit shit.

Drop a picture of the foot here so we can have a look at if it is printable for a start?
That's the thing, couldn't find an image with some searches but will look harder over the next few days.
Similar to the Tek one posted earlier but different in that they fit nicely with the corner of the case and they're quite long ~60 mm IIRC. Screw hole down the guts as is normal. As I remember they were a hard black rubber that got real brittle with age and they fell into chunks.
Someone here will have them and hopefully do a measure up so someone can do a 3D model.
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #43 on: March 14, 2019, 12:52:52 am »
Looks like making something to do the job will be easy. Making a look alike without a sample impossible and not really that important I guess.

https://youtu.be/Cmz8bzUsj7E?t=1038

If you can measure the footprint or even the area available and where the screw sits relative to the edge and it's dimensions and a height needed to clear the transformer cover is all we would need to roll you a design based on the Tek one shown earlier.
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #44 on: March 14, 2019, 01:27:16 am »
Looks like making something to do the job will be easy. Making a look alike without a sample impossible and not really that important I guess.

https://youtu.be/Cmz8bzUsj7E?t=1038

If you can measure the footprint or even the area available and where the screw sits relative to the edge and it's dimensions and a height needed to clear the transformer cover is all we would need to roll you a design based on the Tek one shown earlier.
Yep, them's the buggers.
As these HP's use an IEC lead there's really no need to have slots for the mains cable but the feet do need to be long enough to give good clearance for the CRT cover to ground.
Remember, these also used insulating feet for the days when it wasn't frowned upon to float your scope.

1/ So length required is 40 mm.
2/ Screw CL to case side edge max 10.5 mm. (so 21 mm min wide and square)(see 4 and 5)
3/ Screw CL to case top/bottom edge max 15.5 mm.
4/ Back panel to case edge/rim step 2.2 mm (in case you want to step up over it and make the foot slightly larger to the case side edge.)
5/ Case rim width 3.2 mm.
6/ Standard screw: remaining meat at bottom of screw recess 13.5 mm.
7/ Screw allow 3.5 mm dia.
8/ Screw head/washers allow for 8.5 mm dia.

These should fit in any of the 4 positions.
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #45 on: March 14, 2019, 01:54:08 am »
Literally 5 minutes work.

Strongly suggest you run the bolt nearly full length to avoid layer shear. If the screw is to stay at 3.5mm then running a tube outside of that will help a lot so 3.5x5 or 6mm? Personally I would look and see if the chassis can be drilled and tapped to maybe 6mm?

The Foot outer I have made 31mm Square so a 5mm lip, partly it will give better stability when sitting on the feet but also would allow cable wrapping. The lower square is 21mm BTW

Simple print job when finished and I will send you a couple of sets over to play with.  :)

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #46 on: March 14, 2019, 02:19:02 am »
Literally 5 minutes work.

Strongly suggest you run the bolt nearly full length to avoid layer shear. If the screw is to stay at 3.5mm then running a tube outside of that will help a lot so 3.5x5 or 6mm? Personally I would look and see if the chassis can be drilled and tapped to maybe 6mm?

The Foot outer I have made 31mm Square so a 5mm lip, partly it will give better stability when sitting on the feet but also would allow cable wrapping. The lower square is 21mm BTW

Simple print job when finished and I will send you a couple of sets over to play with.  :)
Yeah they could be improved some however without cord slots they should be stronger.
I've allowed for 5 mm screw thread engagement with the standard screw that while this 1740 I have here has zero feet all the screws are there.  ::)
While I could put bigger screws in most that own these would just want a drop in replacement so it's a shame we haven't got the original length so ppls could just print one or two to suit their immediate needs.
Thought you'd add a lip.  ;)

Thanks again, that's very kind or you but these are a commonly missing/broken part and I was just trying to add to the great future resource you're building.
Only got one unit here and not likely to be chasing another as this was a freebie I'be had for some years and still haven't got around to fixing.  ::)
One set will be fine.  :)
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #47 on: March 14, 2019, 02:53:44 am »
Literally 5 minutes work.

Strongly suggest you run the bolt nearly full length to avoid layer shear. If the screw is to stay at 3.5mm then running a tube outside of that will help a lot so 3.5x5 or 6mm? Personally I would look and see if the chassis can be drilled and tapped to maybe 6mm?

The Foot outer I have made 31mm Square so a 5mm lip, partly it will give better stability when sitting on the feet but also would allow cable wrapping. The lower square is 21mm BTW

Simple print job when finished and I will send you a couple of sets over to play with.  :)
Yeah they could be improved some however without cord slots they should be stronger.
I've allowed for 5 mm screw thread engagement with the standard screw that while this 1740 I have here has zero feet all the screws are there.  ::)
While I could put bigger screws in most that own these would just want a drop in replacement so it's a shame we haven't got the original length so ppls could just print one or two to suit their immediate needs.
Thought you'd add a lip.  ;)

Thanks again, that's very kind or you but these are a commonly missing/broken part and I was just trying to add to the great future resource you're building.
Only got one unit here and not likely to be chasing another as this was a freebie I'be had for some years and still haven't got around to fixing.  ::)
One set will be fine.  :)

Extruding down to the lower level of 13.5mm is easy as is dropping back to the 3.5mm hole (3D print cross sections shown done below). The major difference with 3D printing over injection or rubber molding is the layer shear strength. As a design I will post a drop in replacement and a 6mm bore as shown above.

Some of the shear issue can be helped with the use of PETG (in my case as I don't currently run nylon or ABS) and raising the perimeter shells and infill. Below is 6 perimeters and 40% infill. The area will remain the weak point without the bolt running full length. The infill could be pumped up which will help a bit but it becomes the law of diminishing returns as it is still a point load at the head of the screw.

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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #48 on: March 14, 2019, 03:01:51 am »
Literally 5 minutes work.

Strongly suggest you run the bolt nearly full length to avoid layer shear. If the screw is to stay at 3.5mm then running a tube outside of that will help a lot so 3.5x5 or 6mm? Personally I would look and see if the chassis can be drilled and tapped to maybe 6mm?

The Foot outer I have made 31mm Square so a 5mm lip, partly it will give better stability when sitting on the feet but also would allow cable wrapping. The lower square is 21mm BTW

Simple print job when finished and I will send you a couple of sets over to play with.  :)
Yeah they could be improved some however without cord slots they should be stronger.
I've allowed for 5 mm screw thread engagement with the standard screw that while this 1740 I have here has zero feet all the screws are there.  ::)
While I could put bigger screws in most that own these would just want a drop in replacement so it's a shame we haven't got the original length so ppls could just print one or two to suit their immediate needs.
Thought you'd add a lip.  ;)

Thanks again, that's very kind or you but these are a commonly missing/broken part and I was just trying to add to the great future resource you're building.
Only got one unit here and not likely to be chasing another as this was a freebie I'be had for some years and still haven't got around to fixing.  ::)
One set will be fine.  :)

Extruding down to the lower level of 13.5mm is easy as is dropping back to the 3.5mm hole (3D print cross sections shown done below). The major difference with 3D printing over injection or rubber molding is the layer shear strength. As a design I will post a drop in replacement and a 6mm bore as shown above.

Some of the shear issue can be helped with the use of PETG (in my case as I don't currently run nylon or ABS) and raising the perimeter shells and infill. Below is 6 perimeters and 40% infill. The area will remain the weak point without the bolt running full length. The infill could be pumped up which will help a bit but it becomes the law of diminishing returns as it is still a point load at the head of the screw.
Understood and still reminding you the feet should provide full insulation so any metal fixings needs be recessed some.

BTW, we might be best for someone that has a HP1740 to chime in with the correct length for the feet.
« Last Edit: March 14, 2019, 03:19:24 am by tautech »
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Re: Replacement Knobs, Feet and Fittings for Test Equipment
« Reply #49 on: March 14, 2019, 03:07:14 am »
HP Knob Onesie to suit 1/4" shafts.

Modded the CAD file back to a single piece version to suit 1/4" Bore and approximately 14mm long round shafts. As shown I looked at running 2x3mm knurl nuts for the grubscrews but they are to long even at 3mm to be made work. The working version uses a 3D printed 3mm thread which turned out reasonably well formed at 0.1mm layer height. I don't have any grubscrews currently is the reason for normal ones shown. Also YES the bore is deliberately very tight on the shaft to minimise the work the grubscrews need to do.

Printing details as per the 3 piece version a few posts ago. 0.1mm layer no detection of thin walls etc.

What I would suggest to make it work better is sharpen a point on the 3mm grubscrew to bite into the shaft to allow a little less screw tension (don't strip the thread) and to then apply a drop of thin CA glue to the head of the grubscrew when in the correct position which should wick down the thread/knob interface and help it stay with less chance of it stripping.

Cad and STL in a Zip file at the Google Drive Link https://drive.google.com/open?id=1DrCOmr-j3UumHvSVMzbPccIYiV4O_ox6
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 


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