No matter how much I measure before hand......

SgtWookie

Joined Jul 17, 2007
22,230
Just squeeze that 1N5821 in a vice a bit...

That reminds me... I once saw that someone had tuned the value of a resistor by using a Dremel moto tool (or similar) and a small rotary sanding drum to take a "U"-shaped section out of the side of it...
 

Ron H

Joined Apr 14, 2005
7,063
Just squeeze that 1N5821 in a vice a bit...

That reminds me... I once saw that someone had tuned the value of a resistor by using a Dremel moto tool (or similar) and a small rotary sanding drum to take a "U"-shaped section out of the side of it...
I once used a Dremel to change a 1N5821 to a 5082-2835.;):D
 

Jaguarjoe

Joined Apr 7, 2010
767
Just squeeze that 1N5821 in a vice a bit...

That reminds me... I once saw that someone had tuned the value of a resistor by using a Dremel moto tool (or similar) and a small rotary sanding drum to take a "U"-shaped section out of the side of it...
I think that only works with carbon composition resistors. It's been a long time....
 

#12

Joined Nov 30, 2010
18,224
LOL! Practice, practice, practice. You'll get better or learn to let the fat ones live half an inch off the board. ;)
 

KMoffett

Joined Dec 19, 2007
2,918
I think that only works with carbon composition resistors. It's been a long time....
Actually, we've done that to increase the resistance of chromium coated tungsten rods used for vacuum deposition. Shaved the diameter to half over the length of the rod with a diamond burr. ;)

Ken
 

Markd77

Joined Sep 7, 2009
2,806
Quote:
Originally Posted by SgtWookie
Just squeeze that 1N5821 in a vice a bit...

That reminds me... I once saw that someone had tuned the value of a resistor by using a Dremel moto tool (or similar) and a small rotary sanding drum to take a "U"-shaped section out of the side of it...


I think that only works with carbon composition resistors. It's been a long time....
Definitely not going to work with wire wound resistors...
 

ErnieM

Joined Apr 24, 2011
8,377
@jerseyguy: can you use a SMD diode on the back side? It might look a little cleaner if you can get a large enough package to span the thru holes.

Wish I could say I'm immune to these things too. Just last week I found I had miswired a SOT-23 AGAIN! I seem to have a particular brand of mental defect I refer to as "transistor dyslexia," the complete inability to understand the simple spacial relationships between base, emitter and collector.

In this case, I was laying out a previous working PCB design to a new form factor, same parts, different board shape. I "improved" the SOT footprint to the "standard" pin 1 2 & 3 configuration without checking my schematic symbol which was laid out to some random configuration, so the auto router and design rule checks thought all was fine. And since I had already made "this" board I shorted my manual checks.

Fortunately I could spin the device and still get proper connectivity to ship my prototype.
 

Wendy

Joined Mar 24, 2008
23,421
I have a set of templates I call PaintCAD. I try to draw the components as close to real size as possible, Someone mentioned the PCB software, the same thing applies. I use Express PCB, but in this the exact software doesn't matter a lot, the feature is in all of them.

Experience helps, but this is definitely a case of measure twice and cut once.

Look at it this way, it fit. :D
 

Thread Starter

jerseyguy1996

Joined Feb 2, 2008
214
@jerseyguy: can you use a SMD diode on the back side? It might look a little cleaner if you can get a large enough package to span the thru holes.

Wish I could say I'm immune to these things too. Just last week I found I had miswired a SOT-23 AGAIN! I seem to have a particular brand of mental defect I refer to as "transistor dyslexia," the complete inability to understand the simple spacial relationships between base, emitter and collector.

In this case, I was laying out a previous working PCB design to a new form factor, same parts, different board shape. I "improved" the SOT footprint to the "standard" pin 1 2 & 3 configuration without checking my schematic symbol which was laid out to some random configuration, so the auto router and design rule checks thought all was fine. And since I had already made "this" board I shorted my manual checks.

Fortunately I could spin the device and still get proper connectivity to ship my prototype.
I just shoved it in as far as it would go and soldered it on. I decided in the end that I didn't really care if it looked pretty or not.;)
 

Thread Starter

jerseyguy1996

Joined Feb 2, 2008
214
I have a set of templates I call PaintCAD. I try to draw the components as close to real size as possible, Someone mentioned the PCB software, the same thing applies. I use Express PCB, but in this the exact software doesn't matter a lot, the feature is in all of them.

Experience helps, but this is definitely a case of measure twice and cut once.

Look at it this way, it fit. :D
I use expressPCB as well and had to draw the terminal block from scratch. I guess I read the dimensions wrong on the datasheet. But like you said.....it fit....just not very well.
 

ErnieM

Joined Apr 24, 2011
8,377
I'm not familiar with Eagle, I use Orcad's PCB Editor (Allegro), which has a "place bound" property, basically a keep-out area for other place bound shapes. Keeps from putting a part on a part IF you make the footprint correctly.

If.

I would be surprised if Eagle didn't have a similar feature.
 
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