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7

I think you might have a misconception regarding to how far the pressure from the fasteners extends. One subject you might want to have a look into is "bolt joint stiffness". The most popular is the "Rotscher’s pressure-cone method". Essentially there is a pressure cone which radiates outwards with an pressure cone angle a. According to ...


6

That model of encoder is not intended for mechanical measurements. It's meant to be used as a fancy knob with high friction, for turning by hand, say, to pick a position from menu on a display, and trying to couple it to a mechanism for readout is a misguided attempt. What you need is an encoder based on slotted optocouplers or a reflective optocouplers. ...


4

The flat on the encoder shaft would typically be used for set screw. If you are able to get a gear or wheel with the right size shaft then adding a screw should be relatively straightforward. This will not only hold the gear onto the encoder, but also give it some increased tortional strength which should be better than just epoxy. If you are unable to get ...


3

Typically, most threads on pipes (in the USA at least) are male NPT and all the couplings or fittings are female NPT. You can connect two pipes with a coupling as long as the last pipe added is free to rotate about its axis. A union is used for easy removal of pumps and other serviceable equipment that would otherwise not be easily unthreaded. It is also ...


3

Well I would suggest that you don’t thread one of the items - just have a clearance hole then a locking nut. Then, to get a precise position have a hole with a locating pin - this will ensure the positioning.


3

A few things, hopefully helpful: Differential thermal contraction is almost certainly your enemy. For most engineering materials, the vast majority of thermal contraction occurs between 300 and 77 K, the two temperatures you are working at. Your PCB is almost certainly shrinking much more than the thing attached to it and cracking your epoxy (normal resin ...


2

A little late to the game. A method recommended in B&W's Steam, Its Generation and Use, is to drill small, closely set holes in the metal substrate, insert the individual wires into the holes, and peen them in place. This avoids the issues others have raised of welding affecting the properties. It provides intimate contact with the measured surface. ...


2

For an easily removable option you can use Kapton tape. It is heat resistant and works well for holding a thermocouple temporarily in place. I also wrap the wires in Kapton for electrical isolation.


2

I ended up finding a solution that works (haven't tried the cements suggested by others yet). The trick was to use a spot welder rather than a tig welder. With the correct power settings, that stuck the TC to the surface without damaging either component. It's not exceptionally strong (I used very fine TC wires), but it should result in conditions that ...


2

Assuming you're talking about plates: it would depend on you code, but usually it's the angle between the two joints that matters. If you mean a 90 degree joint with two 45 degree miter angles, I would still treat it as a corner joint. If there is a 10 degree miter angle on each piece so the dihedral angle in the joint is 160 degrees, it would be considered ...


2

Another alternate solution would be to use a Hall Effect sensor. There are many ways to apply a hall effect sensor to measure distance. Most simple might be to attach the hall effect sensor to the motor and count the rotations. Then translated the number of rotation to distance. Below are few reference links that better explains how to use a hall effect ...


2

Long story short : In any moving part you need to use a bearing, however there are many, many types of bearings. The main two types are : https://en.wikipedia.org/wiki/Plain_bearing https://en.wikipedia.org/wiki/Ball_bearing Also important is the direction of the bearing : https://en.wikipedia.org/wiki/Thrust_bearing If you google on 'buy bearing' you can ...


1

My advice is to change the design if possible from vertical split to horizontal. i.e. horizontal vertical Better Not so good The reason is that : in the vertical solution the internal pressure will tend to separate the halves figure 2: Forces developing on a half of cylinder due to internal pressure (source: Mathalino you could go for a design that is ...


1

For a static joint, there are basically three options: Use an adhesive of some sort to overcome irregularities in the mating surfaces. Use a gasket to overcome irregularities in the mating surfaces. Use sufficient clamping force to overcome irregularities in the mating surfaces. For a purely 3D-printed object, option (3) is out: you can't get sufficient ...


1

Use a thin cut extrude, instead of the "Split" tool. Set this to be midplane, and add the total tolerance gap that you require depending on your printer, and how loose you want the puzzle pieces to be.


1

I would use a collar lock with a slide action locking gate. Solves the durability issues and can be used thousands of times. The collar can be square and slide into a dual keyway to support the blue item while a cylindrical gate (spring loaded or not) shuts behind it. Collar thickness determines load bearing capacity.


1

I would agree with your assumption on the weld types. That being said, you could probably just specify a V-groove weld all the way around the joint like this(where xx is the size of the weld) If necessary, you can provide as many details as you need into the callout: Alternatively, you could something like this: Lastly, you could just use 4 separate weld ...


1

Use a 1/4" dia x 3/16" long shoulder screw with 1/16" thick washer. Also use nut and washer on the thread. You can get the screw at: http://www.mcmaster.com/#90298a530/=10jcicb A steel shoulder screw will be much stronger than a rivet and teflon (plastic) bearings. Steel on steel is commonly used in pivots from door hinges to motorcycle chains.


1

Drill small hole in the aluminum, big enuf to put in the TC junction head, then pound the edge of the hole with a center punch, that'll deform the hole to hold the TC in the hole mechanically. Works great in high temperature applications.


1

I would use a thermal epoxy (potting agent) for this. I have done this successfully with a thermistor before. Also I'm not sure, but you probably want to electrically isolate the thermocouple so that you don't lose voltage to an earthed component and thus get an incorrect reading. So a potting agent is great for this (high thermal conductivity, but not ...


1

If you aren't too worried about response speed, you might be able to embed the thermocouple in a thermal grease, then weld a piece of shim steel over the top to provide mechanical support. I have only ever seen thermocouples welded directly to a substrate before with spot welding equipment.


1

I'd agree that you're looking for an epoxy that stays relatively flexible upon curing, especially if the thermal expansion rates of the epoxy and substrates are different. If you haven't already done so, I'd recommend searching for "underfill" epoxy. There are a few Loctite and Masterbond products that fit the bill. They typically flow very well during ...


1

I think for that I'd probably try using MasterBond EP21TCHT-1 for what your looking for, It has excellent performance on difficult to bond materials and is also excellent at cryogenic temperatures from minus 450 degrees F (4 degrees K) right up to +400 degrees F. The surfaces need to be spotless though, absolutely grease free and slightly roughened for best ...


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