• We want to encourage those of you who ENJOY our site and find it USEFUL to DONATE and UPGRADE your membership from active member to donating or premium membership. If you want to know the differences in membership benefits, please visit THIS PAGE:

    https://www.hobby-machinist.com/premium/

    Donating memberships start at just $10 per year. These memberships are in fact donations that help pay our costs, and keep our site running!
    Thank you for your donation, God Bless You

  • As some of you know, I have wanted to stop managing H-M for some time. It's a tremendous strain on my personal life. I want to set up my own shop. In September, September 15, to be exact, it will be 8 years that Hobby-Machinist has been in existence.

    We've seen a lot of changes. In March, 4 moderators left to start their own site. They took some of you with them. So now you have split loyalties. You know who you are. They didn't like my way of managing this place, and thought they could do better without me. They didn't. The only thing holding them together is that they hate me. Their site was down until mid July. That is why I wanted to stay involved on here until they could learn to run this place. But they wanted me to leave right away, without the training part.

    Anyway, I have been training VTCNC to run things here. Dabbler is going to learn too. I feel that they are ready to start taking over the operation. I will be here to help in case they need, but I don't think they will. Tony Wells is and will be here also to consult with. I will be doing backups, upgrades, and installing addons. Other than that, I don't want to know about this place.

    What about the 4 moderators who were disloyal? I don't care. It isn't my call anymore. I would think that, rather than fumble, they ought to come back and do good work. That's up to them. If they want to return to try to lead more members to their site, I am done caring. I suffered too much aggravation worrying about it. I don't plan to spend any more. What they do impacts on them. I have my own opinions including those of you who followed them there. No longer my problem.

    I am leaving this place in good operating condition, and financial condition.
    --Nelson
[4]

Finding center of 3/4 rod

[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

umahunter

Active User
Registered
Joined
Jan 21, 2014
Messages
641
Likes
353
#1
Ok tell me if I'm thinking correctly say I want to find quick center on a say 3/4 small rod. if I put that rod in a 5c collet block shouldn't I then just be able to find the center of the block thus putting me on the center of the rod or pretty close. I know this all depends how accurate the collet and block are but am I thinking correctly or am I off ???? I just need to drill a cross hole a bolt will go in to hold a rod in a plasma cutter circle cutter so it doesn't need to be NASA accurate lol
 
Last edited:

P. Waller

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Mar 10, 2018
Messages
328
Likes
195
#3
Measure the part diameter, if it is .735 edge find it and move 1/2 this diameter, done deal.
 

higgite

General Manger - Proofreading Dept.
H-M Supporter - Gold Member ($25)
Joined
Aug 15, 2013
Messages
793
Likes
836
#4
You could certainly do it that way, but I’m curious why you would do that instead of just finding the center of the rod? Maybe I’m missing something, but it seems that one would be just as quick as the other.

Tom
 

Franko

Active User
Registered
Joined
Feb 24, 2015
Messages
1,327
Likes
1,118
#5
I'd clamp a V-block in my mill vise and visually locate the center with a center drill.
Clamp your rod in the V-block and make a dimple or starter hole with the center dril.
Then chuck your chosen drill bit and drill the hole.
 

P. Waller

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Mar 10, 2018
Messages
328
Likes
195
#6
You could certainly do it that way, but I’m curious why you would do that instead of just finding the center of the rod? Maybe I’m missing something, but it seems that one would be just as quick as the other.

Tom
This is how you find the center, 1/2 the diameter from the OD, when finding center of a part held in a collet block in a mill find the center of the part rather then the center of the tool holding device thus reducing any errors in the part holding.
 

Charles Spencer

Active User
H-M Supporter - Silver Member ($10)
Joined
Aug 29, 2013
Messages
1,046
Likes
1,111
#7
Unlike the end there is no one center on the side of a cylinder. Every spot for 360 degrees around it has the potential to be the center. Since tolerances aren't too tight I think I would proceed by:

1. Bluing the side and the end of the rod
2. clamping it down
3. Using a 3/8" block, scribe the end and the side
4. clamp it in a vee block using the scribed line on the end to ensure that it is perpendicular to the spindle
5. mark the hole's location with a center punch
6. make your hole
 

MarkM

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Apr 23, 2017
Messages
230
Likes
158
#8
Scribe three chords. Divide the length of each chord in half and using a square scribe lines. Where they intersect is the centre.
 

kd4gij

Active User
Registered
Joined
Feb 7, 2011
Messages
4,587
Likes
1,758
#9
^ All that just to find the center of a rod? ^ I just use an edge finder on the side of the rod and move over half dia.
 

MarkM

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Apr 23, 2017
Messages
230
Likes
158
#10
I guess I should have read the post properly. I Thought the o.p. Was referring to the face of the rod. Ya I agree I d just touch off and move half plus half the diameter over since Nasa wasn t waiting.
 

higgite

General Manger - Proofreading Dept.
H-M Supporter - Gold Member ($25)
Joined
Aug 15, 2013
Messages
793
Likes
836
#12
Build a round bar center finder?

1) dig an iron mine
2) make charcoal
3) smelt
4) etc etc.

=OR=

https://www.mscdirect.com/product/details/76416528

:)

MetaKey
I have one of those gizmos. Works fine, but not NASA approved. ;) I haven't tested it against the edge finder +1/2 diameter of work + 1/2 diameter of edge finder since I haven't needed that precision, but it's better than my eyeball and it's quick.

Tom
 

umahunter

Active User
Registered
Joined
Jan 21, 2014
Messages
641
Likes
353
#13
Lol I did it I just found the center of my block quick stripe of dykem scribed a line located line spotted and drilled hole thanks for all the replies
 

Chip Hacket

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Jul 12, 2015
Messages
187
Likes
140
#14
Mount the rod with V block in vise.
Put flat bottom end mill in collet.
Lower quill until it just barely makes a flat on the rod. That’s the center of your rod. Drill there.

Using edge finder then moving over 1/2 is still better I think. But this works pretty well.
 
Last edited:

westerner

If you are gonna be stupid, ya gotta be TOUGH!
H-M Supporter - Gold Member ($25)
Joined
Mar 29, 2017
Messages
123
Likes
179
#16
Lol totally space this was sitting at the back of my drawer
Oh, boy, THAT'S funny! It happens around here more and more. Best part of that is SWMBO is unaware of this development (we hope).
Might make for some awkward conversations later. "Don't you already HAVE one of those:cautious:?" LOLOL. I have certainly been there!
 

hman

Active User
H-M Platinum Supporter ($50)
Joined
Feb 17, 2013
Messages
1,699
Likes
1,325
#17
I have and occasionally use a center finder like that. It's pretty good within +/-.005". To increase accuracy, I'll usually "find center" from one direction, zero the DRO, approach from the other direction and compare. Then just for fun, I'll rotate the spindle 180º and repeat.
 
[6]
[5] [7]
Top