Center Finder.

[toxo]

How many times do we punch out a circle or draw around something to get a circle and then find that we don't have a center to work from? If we draw the circle with a compass we have to deal with a hole in the middle. I determined to get a center finder for this job so earlier this year I bought one online and as usual I didn't pay attention and this turned up.

So I went back online to look for one like I used to have on my combination square. I bought one with a center finder on it and this turned up minus the center finder.

They did refund my money and told me to keep the junk. At this point I decided to make one, it's not rocket science and I had the welder out already so I found a couple bits of steel and set to. It's ptretty much there already but when I'm sure I'll weld it properly and might even put some paint on it. Happy days.

 

[Littlef]

I have a similar tool that's aluminum with a steel ruler.  Its odd that mine doesn't find the exact center.   Playing around with mine, I found a process to get the center point.  I draw the first line through "center."  Then, I turn it 180 degrees, and it draws a parallel line about a MM away from the first line.  Then, I turn it 90 degrees and draw an intersecting lien.  Then I turn it 180 degrees again and draw the 2nd parallel line.  When I'm done, there's a tiny square in the middle, instead of a single point.  The center of the tiny square is the center of the circle.  I thought about returning the tool, but I think that's precise enough for anything I'm doing.  

Edited Tuesday at 07:55 PM by Littlef

[toxo]

That's annoying but as you say it's usable. If it's aluminium you should be able to clamp the v in a vice and give the edge a gentle tap in the direction of where it needs to be. 

[Littlef]

17 hours ago, toxo said:

That's annoying but as you say it's usable. If it's aluminum you should be able to clamp the v in a vice and give the edge a gentle tap in the direction of where it needs to be. 

I think any attempt to bend this would just warp or crack it.  The red base is 1/2" thick and the ruler is steel.  At least I worked out a process to make it usable.

 

[toxo]

5 minutes ago, Littlef said:

I think any attempt to bend this would just warp or crack it.  The red base is 1/2" thick and the ruler is steel.  At least I worked out a process to make it usable.

 

Not talking about bending it. Were talking a quarter of a millimeter. A gentle tap is all that's needed on the end. Nothing to lose but if you're not comfortable...

[fredk]

or, superglue a thin sliver of plastic to the edge of the ruler and carefully sand it away until its just right

[chuck123wapati]

18 hours ago, Littlef said:

I thought about returning the tool, but I think that's precise enough for anything I'm doing.  

1 mm is pretty close especially for leather work.

 

22 hours ago, toxo said:

How many times do we punch out a circle or draw around something to get a circle and then find that we don't have a center to work from? If we draw the circle with a compass we have to deal with a hole in the middle. I determined to get a center finder for this job so earlier this year I bought one online and as usual I didn't pay attention and this turned up.

So I went back online to look for one like I used to have on my combination square. I bought one with a center finder on it and this turned up minus the center finder.

They did refund my money and told me to keep the junk. At this point I decided to make one, it's not rocket science and I had the welder out already so I found a couple bits of steel and set to. It's ptretty much there already but when I'm sure I'll weld it properly and might even put some paint on it. Happy days.

 

pretty cool!!

 

[toxo]

8 minutes ago, chuck123wapati said:

1 mm is pretty close especially for leather work.

 

pretty cool!!

 

Thanks Chuck.

[chuck123wapati]

for those without welders here are a couple ways to find center without extra tools. Sorry for the light  lines.

1.  with just a square find the diameter then divide that number and mark both points on the edge of the circle turn the square over and align it with the marks and the measurments on the square.

2. use a compass , find the diameter divide in half then put thepointy end on  the edge and draw an arc, move it anywhere basicly and draw another or a few. 

3. The easiest way, buy a compass and blunt the point a bit so it doesnt poke a hole in the leather and draw on the back of you piece. In my case i simply installed the point backwards.

[chuck123wapati]

2 minutes ago, toxo said:

Thanks Chuck.

yw  

[toxo]

4 minutes ago, chuck123wapati said:

for those without welders here are a couple ways to find center without extra tools. Sorry for the light  lines.

1.  with just a square find the diameter then divide that number and mark both points on the edge of the circle turn the square over and align it with the marks and the measurments on the square.

2. use a compass , find the diameter divide in half then put thepointy end on  the edge and draw an arc, move it anywhere basicly and draw another or a few. 

3. The easiest way, buy a compass and blunt the point a bit so it doesnt poke a hole in the leather and draw on the back of you piece. In my case i simply installed the point backwards.

I hate smart kids

[chuck123wapati]

1 minute ago, toxo said:

I hate smart kids

lol they used to teach this stuff in grade school. a compass, ruler, protractor and square were basic tools back in the day. 

[toxo]

50 minutes ago, chuck123wapati said:

lol they used to teach this stuff in grade school. a compass, ruler, protractor and square were basic tools back in the day. 

I will admit to learning most of this stuff as well though forgotten most of it. Never used the try square one but used the compass method a lot. Also using a small leather patch to put the point on works as well.

As an aside, talking about learning stuff, I needed the learning at one job I did. I was given the drawings of a water heater to accompany an enormous on site concrete mixer to cold climates. Was 9ft dia and a little taller with a chinese hat roof. Because my face didn't fit I had to make everything out of scrap 1/8th plate so lots of cutting and welding before I could even start. The fun started when the drawings only gave the apex of the roof so with only the radius to go by I had to make the overall diameter and then work out how much of a wedge to cut out to arrive at the required height. Good job I thrive on that shit.

Edited 15 hours ago by toxo

[chuck123wapati]

25 minutes ago, toxo said:

I will admit to learning most of this stuff as well though forgotten most of it. Never used the try square one but used the compass method a lot. Also using a small leather patch to put the point on works as well.

As an aside, talking about learning stuff, I needed the learning at one job I did. I was given the drawings of a water heater to accompany an enormous on site concrete mixer to cold climates. Was 9ft dia and a little taller with a chinese hat roof. Because my face didn't fit I had to make everything out of scrap 1/8th plate so lots of cutting and welding before I could even start. The fun started when the drawings only gave the apex of the roof so with only the radius to go by I had to make the overall diameter and then work out how much of a wedge to cut out to arrive at the required height. Good job I thrive on that shit.

 i am going to make one like yours for my wood lathe work it will be handy. 

[DwightT]

A while back I was looking for a center finder and stumbled on this site:

https://www.instructables.com/Homemade-center-finder-tool-quick-cheap-easy/

I haven't actually made one yet, but it looks like it would be easy enough to do.

    /dwight

[chuck123wapati]

11 minutes ago, DwightT said:

A while back I was looking for a center finder and stumbled on this site:

https://www.instructables.com/Homemade-center-finder-tool-quick-cheap-easy/

I haven't actually made one yet, but it looks like it would be easy enough to do.

    /dwight

now thats the ticket!!!

[toxo]

47 minutes ago, DwightT said:

A while back I was looking for a center finder and stumbled on this site:

https://www.instructables.com/Homemade-center-finder-tool-quick-cheap-easy/

I haven't actually made one yet, but it looks like it would be easy enough to do.

    /dwight

I saw a few like that online but they were too small. Just as good a design as any if you're gonna make one though.

The ones I saw had three pips though.

Edited 13 hours ago by toxo

[Littlef]

4 hours ago, chuck123wapati said:

1 mm is pretty close especially for leather work.

 

pretty cool!!

 

I use mine far more for wood working than leather, but it comes in handy to find the center of a circle, regardless of the medium.    - the center point is far enough out , that I can see on a quick glance that its off.  But I worked out the process and I explained above to get the actual center. (or at least close enough that it works for me.)

[Littlef]

4 hours ago, chuck123wapati said:

lol they used to teach this stuff in grade school. a compass, ruler, protractor and square were basic tools back in the day. 

  I remember doing this in geometry.    - Probably did this in a drafting class also, but that's been many many moons ago.   

[chuck123wapati]

3 minutes ago, Littlef said:

  I remember doing this in geometry.    - Probably did this in a drafting class also, but that's been many many moons ago.   

yeah i'm a youngun at 65 lol I never quit using them thats all. 

[DwightT]

3 hours ago, toxo said:

I saw a few like that online but they were too small. Just as good a design as any if you're gonna make one though.

I think if you are making one you could make it any size you want.  The author of that page even mentions that you could scale them to any size, just keep your pin circles the correct size for your pins and spaced appropriatly.

    /dwight

[dikman]

I like that little dohickey, I'll have to make one.