Questions tagged [fasteners]
The fasteners tag has no usage guidance.
84
questions
1
vote
1
answer
29
views
Maximum tensile and shear loads on screw
I'm using a screw in an application where I want to have a high degree of confidence the screw will not fail, and I want to be sure I'm calculating the maximum tensile and shear loads it can sustain ...
- 113
0
votes
1
answer
45
views
Spring clamps recommendations to lock a breadboard when inserted
I need to lock a soldering breadboard to a 75 mm coupler cap. The picture below is upside down: the board will be hanging underneath the coupler cover.
And the assembled pic:
The board is inserted ...
- 101
5
votes
3
answers
681
views
Origins of the "threaded fastener pullout formula"
I was looking through NASA's document for "Installation Torque Tables for Noncritical Applications" and noticed their formula for the pullout load of a fastener on a certain material. It ...
0
votes
1
answer
29
views
Distorted threads and bolt preload
Say a bolt is clamping 2 plates together, by threading into a distorted thread in the bottom plate. After the thread is used several times and becomes less distorted, will the relationship between ...
- 1
0
votes
2
answers
27
views
Sleeve nut with non-circular cylinder
I've been scouring the internet for hours to find this type of nut. The requirements are fairly simple:
I want to cut holes into two metal sheets to join them with some kind of fastener (e.g. nut and ...
- 1
0
votes
2
answers
55
views
What is this fastener? Brass colored, three slots of some type. (And how to remove it?)
Here's a close up:
This vehicle license-plate holder uses three of them: Unfortunately I can't see behind.
Note, ignore the four small dimples on the plastic arranged rectangularly; unrelated.
What ...
- 111
-1
votes
3
answers
112
views
Inline pull load rating of lag bolts in wood?
Is there some sort of general guidance or load rating for wood screws (lag bolts) going into framing wood where the force is pulling directly inline with the screw orientation? More context and ...
0
votes
0
answers
65
views
Do automatic quick release mechanisms exist?
I'm imagining something like a cable tie that would automatically release after a certain amount of tension was applied.
I guess a very basic way to do it would be to use different diameter strings ...
- 101
0
votes
2
answers
55
views
Are bolt and nut dimensions standardized?
Given the nominal size of a bolt/nut, e.g M10, can one construct all other dimensions from it? Do these dimensions differ between manufacturers or are these standardized. If so, where can I find ...
0
votes
2
answers
50
views
Is high TPI sheet metal screw stronger for thin materials?
I just discovered that in addition to standard #10-12 sheet metal screws, there are #10-16 and even #10-24 versions available. I'm planning to use them on 0.06" thin aluminum, 0.12" nylon ...
- 155
0
votes
0
answers
21
views
Securing Removable "Clocked" Handrail Knobs
I am in the process of machining and assembling a smokebox for a model train. The smokebox in question is approximately 35mmx35mmx22mm. There are a series of handrail knobs and rails that are to be ...
- 31
0
votes
1
answer
75
views
Can you explain mathematical and mechanics formulation of equation in Junker 1969 paper on self-loosening of fastener by vibration?
Can you help me to understand how the first equation in the paper 'New Criteria for Self-Loosening of Fasteners Under Vibration' by GH Junker, 1969 is derived? I'm not able to understand the ...
0
votes
2
answers
50
views
I am designing a light that is hung from the end of an arm. How do I calculate the amount of force on the fastener where the arm attaches to the wall
I have a light hanging from an arm that is attached to the wall. I need to make sure that the fastener at the wall end is able to hold the weight. How do I calculate this?
- 3
0
votes
0
answers
24
views
How to pull a component through a panel cutout using a screw mechanism?
I have a camera fixed to a cube frame structure made from aluminium extrusion. The frame will be covered by a 3 mm thick fibreglass enclosure (this is highly rigid) with a cutout for the camera, which ...
- 103
0
votes
2
answers
73
views
Remove stripped screw inside of a tube
I have a stripped screw inside of a tube (see picture):
The size of the screw is M2 and it seems to be glued. This is part of a camera objective so I want to avoid impact (e.g. tapping with a hammer)....
0
votes
1
answer
55
views
Why aren't fasteners open standards?
I just wanted to find information for an M2 flat head hex socket machine screw which, I believe, is defined by ISO 10642, but unfortunately that is locked behind a paywall of a couple hundred dollars. ...
- 101
0
votes
3
answers
155
views
Is it possible to tap a hole partially through a 3mm aluminium sheet?
I would like to secure components to an aluminium sheet that is 3mm thick. Ideally I do not want to drill holes all the way through the sheet because it is important that a seal is maintained.
I am ...
- 103
0
votes
0
answers
70
views
Which side is "up" on this nylon nut?
I have this nylon nut, and I wonder which side should contact the material:
Is it the wide hex face, because the nut is built like a lock-nut?
or is it the cylindrical face because it serves as an ...
- 191
0
votes
1
answer
30
views
What type of rivet is this?
This is a pivot point on a linkage in my coffee table. It appears to be a rivet with a tail that was pressed with a cross-shaped punch to widen it. I haven't see something like this before. Is there a ...
- 35
1
vote
3
answers
98
views
Steel bracket fixing spacers on a wall
What could I do to address the uneven vertical wall (not plumb) behind the bottom of the steel bracket?
Would you fill in the gap with sand/cement and once dried tighten the bolt or use steel plates ...
1
vote
1
answer
72
views
Screw Calculations/Math
At the risk of every woodworker in the world snickering at me, I'm curious how strong my wood joints are and want to know how much weight a table supports. I'm an aero engineer who ended up in EE, but ...
- 155
0
votes
1
answer
124
views
Unable to understand minimum length of engagement for bolts
I've attached a snap of the part I'm unable to understand Machinery's Handbook 29th Edition.
Here's a link to the ebook as well https://www.vtc1.org/cms/lib/PA03000913/Centricity/Domain/21/Machinerys%...
- 37
0
votes
3
answers
125
views
Does the nut experience the same forces a bolt experiences but in opposite directions as reaction forces?
More specifically, if I have an eye bolt being used to lift a body, I can find the various stresses acting on the bolt, but I want to know what happens to the threaded area of the body where the eye ...
- 37
1
vote
2
answers
150
views
Solutions for a slanted roof
I'm using I-Joists to span this 27' vaulted living room and create a shed style roof. I've got two problems. Because of the angle, the joist won't make full contact with the walls (short of 20 years ...
- 117
1
vote
3
answers
307
views
What is the real name of those rivet-like plastic fasteners?
I'm trying to find the name of a removable fastener operating by a deforming retainer in the front like in the picture:
[
All I found online are Alibaba and similar listings that don't seem to contain ...
- 11
5
votes
4
answers
2k
views
Why can't screws be used for locating parts?
I remember hearing awhile back that it's not a good idea to use screws to locate/align parts. Why is that? Apparently dowel pins, or "locating pins" should be used instead. From my ...
2
votes
5
answers
2k
views
Are there any benefits to using a regular washer alongside a lock washer?
I am new to fasteners in general, and was wondering if anyone knew if it was acceptable to use a regular washer underneath a split lock washer. There are two applications, one is on top of a 3D ...
23
votes
5
answers
6k
views
Why exactly does a washer help distribute the stress around a bolt?
Usually the reason for having a washer under a bolt head is stated to be that it helps to evenly distribute the stress to the clamped material surface. But why is this?
I would understand if the ...
- 2,209
1
vote
3
answers
524
views
Mechanical fasteners made of HDPE?
I need to fasten pieces of HDPE together but I’ve heard gluing HDPE is difficult (after all, glue comes in HDPE containers, and the glue doesn’t get stuck in the bottle).
Using mechanical fasteners ...
- 131
0
votes
0
answers
52
views
Thread adapters larger than 1/2"
I have a 1/2-20 stud that I need to step up to a 3/4-16 stud. I searched around for 1/2-20 female to 3/4-16 male thread adapters, but was only able to find such a product on McMaster for sizes 1/2 and ...
- 101
0
votes
0
answers
851
views
Maximum strength size thread for aluminium sheet per thickness
Is there a rule of thumb, or a table which helps one determine what is the maximum strength thread size to use for aluminium sheet?
I am interested in threading 3mm, and 2mm thick sheet aluminium. I ...
- 101
0
votes
1
answer
182
views
What type of fastener / rivet is this please?
I think I may have worked this out but I would love it if a real engineer could confirm it please? Is the fixing shown in the photos a shoulder rivet? Semi tubular? For the record the pictures show ...
- 1
0
votes
1
answer
59
views
What type of fastener is this? How does it work?
I'm trying to find more information on this type of fastener. It looks like a variation on a bayonet mount but I'm not exactly sure how it is locking in place.
- 101
2
votes
1
answer
115
views
Are concrete screws suitable for repeated removal and reinstallation?
Is a concrete screw like the HILTI HUS3 removable?
I.e. can it be repeatedly unscrewed and reinstalled as required? Will this damage the fixing or the hole in the concrete?
We're thinking about using ...
- 857
0
votes
2
answers
51
views
Mounting a digital indicator on a plate
I have a flat aluminium plate and I need to mount a digital indicator[1] on it.
The digital indicator doesn't seem to have any mounting holes itself so I
think I need to use a clamp to hold it.
I don'...
- 105
0
votes
2
answers
2k
views
What is Proof Load of Bolts?
I seem to be getting conflicting information. Shigley's Mechanical Engineering Design textbook states that, "proof load is the maximum load (force) that a bolt can withstand without acquiring a ...
- 43
0
votes
0
answers
28
views
Is there a term for this kind of eccentrically threaded fastener or washer that has wrench flats and curved faces
Is there a standard term for this fastener or for the kind of problem it is intended to address?
- 203
0
votes
1
answer
87
views
Mounting methods for thin wall cast aluminum
Having a cast aluminium enclosure with the 3mm wall thickness. now I need to mount this to a mounting plate which fixed in vertical walls. can I have some idea on how should I choose the appropriate ...
0
votes
1
answer
37
views
Fasten adjustable perpendicular cylinders rotating on axis
What part(s) make it simple to secure two perpendicular cylinders together when one of the cylinders is rotating on its axis? In the drawing below, C(3) rotates with a simple motor. C(1) and C(2) ...
- 101
0
votes
1
answer
83
views
What is the best way to fasten securely a load onto a hollow brick?
Due to the ongoing COVID pandemic, I decided to put a basketball hoop on one of our outside walls, so that me and my son can stretch a bit. The problem is that the wall I plan to put the basketball is ...
- 24k
0
votes
0
answers
222
views
classes and grades of steel and stainless steel
I'm trying to learn the standard nomenclature for the steel and stainless steel mainly used in the bolts, screws, nuts, and other fasteners in general. So far I have created this table:
| Metric ...
- 249
0
votes
1
answer
1k
views
How to remove/replace a screw with a lock washer in a tight place
I'm trying to remove the screw in the images below from a metal cover.
The screw is locked in place by what I believe is called a locked washer. The screw can rotate, but I can't move it in and out. ...
- 113
1
vote
1
answer
138
views
Detachable tubing connections (joints) for frame assembly
I am looking into fabricating a steel tubing frame that needs to be dis/assembled (applies to many larger furniture like bed, shelving unit, wardrobe, cupboard, cabinet, ...).
What are the variants of ...
- 139
3
votes
0
answers
112
views
Aerospace bolts and washer combination
In my aerospace company we have repetitive discussions regarding the stacking of low tolerance fasteners with non-countersunk washers. For example a fastner NAS6703-X (size 10) has a max. base radius ...
- 31
1
vote
1
answer
862
views
Distribution of Forces into 3D Bolt Group
I'm trying to create an Excel spreadsheet that takes a 3D bolt group with x y and z coordinates, applied loading, and determines the distribution of forces into each bolt based on weighting by the ...
- 79
0
votes
1
answer
526
views
What's the best way to design a joint with two fasteners?
When you're trying to design a relatively long joint with only two fasteners, what's the best way to arrange them? Since fasteners effectively radiate a circle of clamping force around them, what's ...
- 156
-1
votes
1
answer
94
views
Serrated locking part
I need to fixate something at adjustable approximate angles. It doesn't need to have a lot of holding power. So the idea is to have washers/nuts that are serrated, that when closed in together, locks ...
- 149
-1
votes
1
answer
22
views
Looking for the name of this torque-arm post (to order one OTS)
It is a post that has an arm that can swing out so that you can torque on the post. I've seen it before but not sure where!
2
votes
2
answers
6k
views
M# Screw mm per turn?
So is there a standard rule of thumb, or equation about the distance the end of a screw will travel per rotation?
Conversely, how many turns it will take to travel a specific distance?
Say I have an ...
- 121
0
votes
0
answers
25
views
"Barbed" fastener, ideally with a release
I'm trying to identify a fastener or type of fastener. I have a stud/post that comes up through a board and the fastener is something that would push on and hold in place. Ideally it would be ...