When you size a fastener for a load, do you typically make allowances for variation in load due to vibration?
Or would you hope that the variations are covered by a safety factor?
We are having trouble with some screw bosses I have designed...[sadeyes]
I followed the standard design guides available online.
The screw is a #4-20 plastite 45 screw. It secures the connector into a metal housing. The 2 of the 3 screws use a half slot, rather than a hole. These are both...
Does anyone have some rules? I want to make a simple 90 degree twist in some thin copper lead frames (0.8 x 1.5mm). Max twist per length? Does the cross section stay reasonably similar? Is this an ok process for volume production (200k-500k/year)
Similar to the image.
I grabbed a CAD model of Mcmaster and built my jig around the CAD model of the bearing. It wasn't that the CAD model was wrong, it was just a bad selection in general.
The jig tests an electrical circuit board, and wouldn't be used very much; so I did no checks on the bearing loading, rpm...
I have been working 8 years as a designer, and last week found out bearings are predominantly metric.
I designed a test jig and ordered a 0.25" bore, 1" OD bearing from Mcmaster to fit the jig. When we got the bearings they are ultra cheap garbage, with about 1mm of play. I figured I'd just...
I work for an electronics company, we use a lot of stamped copper parts. We have a power module that will get molded as a single stamped array of lead frames. This will be cropped to make the individual circuits later.
Some of the GD&T is being debated with us from the supplier. The issue is...
I actually talked to SolidEdge support and the rep gave me advice to change the STP3D.ini file. After addressing some issues with multiple copies of that file, we were able to import the STEP files correctly.
I am having trouble with some models forwarded by customers.
Consistently the parts come in to a single part file as opposed to being distributed in an assembly file. It is quite time consuming to try to separate their part into parts.
Is there a better solution? I am not sure what options...
Hi Pud,
Thanks for your input. I am not really clear on the dampness/water affects on the resin.
Is this affect only while the resin is peletized? Or does it affect the molded part as well? If only the pellets, what mechanism restricts the affect after molding?
I have an older part and a newer part built from the same mold. Resin batches were obviously not the same. New parts all crack easily.
My first question is; was the correct resin used? Can PBTGF30 be compared and identified from Sabic, 3M, BASIF, Dupont?
Would the FTIR test be a good choice...
Does anyone have experience with Silver Sintering? Pressureless alternatives such as Alpha's Agromax or Henkel's SSP2000?
What would the best plating for a DBC be to work with these sintering processes?
I have received a print with a Flatness tolerance attached to the Datum. As far as I know this is backward, or am I missing a second meaning or interpretation?
I generally see datums attached to a GD&T tolerance.
See attached image.
Thanks.
But back to the original question.
What properties on the datasheet would predict the dimensional stability of a part made of resin X?
I felt that the;
Melt Temperature,
Vicat Softening point,
Deflection Temperatures,
were good indications of how the part would mold. Is there a...
Ok,
Sorry my description was not amazing. By move, I meant that the internal stresses in our "prototype" tooling injection molded part, pulled the room temperature straight sides and left them slightly curved. Approximately 1mm over a 50 mm length.
I think the plastic in it's softened state...
I am designing a plastic enclosure for electronics. I selected a PBT with no glass fiber reinforcement for the prototype, since it should be very predictable dimensionally.
The process engineer has raised concerns about the part "moving" when heated to 90C for 10 minutes.
My thoughts are if...
