Centerline on a dowel

[Dave Norris]

Hi Everyone,

Would anyone have any insight on to how to accurately scribe a centerline down the side of a dowel? When I do it I slowly but surely drop my line off to one side or the other.

Thanks, any help greatly appreciated.

[Dick Brown]

Hope I understand the question. Lay dowel on a flat surface, put another flat surface (thin lath??) approx. 1/2 thickness of the dowel next to it, scribe your line using top of thin surface for reference while making sure dowel doesn't move. If you are working with a larger dowel and have a small angle iron as long or longer than the dowel, just the lay the dowel in it and mark down it using the edge of the angle to stay straight.

[John Coloccia]

So, it should be noted that any line parallel to the axis of the cylinder is a center line, so to speak. With that in mind, there are many different ways to do it depending how complex you'd like to get. It's sufficient to rigidly hold a pencil (hold it up against a wall, for example) and drag the dowel underneath, so long as you don't twist it. Anything along those lines works. You may also lay the dowel on your bench, and drag the pencil along the bench top.

[Garth Almgren]

I was going to suggest something very similar: lay the dowel in a V block and scribe your line where the dowel meets the V block. As long as the dowel doesn't move, you're golden.

[Mike Cozad]

My son and I built model rockets when he was a youngster. We often had rockets with upper and lower fins and needed to draw the lines along the body tube. We used the stop on an interior door frame as our straight edge. Never had an out of alignment fin that way....

[Matt Day]

I have LV's center marker and it works well for turning
http://www.leevalley.com/US/wood/page.aspx?p=43205&cat=1,330,49237&ap=1
You could use the general idea and make something for marking with a pencil
Or buy this
http://www.woodcraft.com/product/2004363/8961/groz-steel-center-finder.aspx
or this, but I don't think it's available any longer
http://www.woodpeck.com/ottpbcenterfinder.html

[ray hampton]

If you can mount the dowel in a lathe and lock the spindle, you can use the carriage or rest to scribe a line from one end to the other end

[Bill Huber]

I have LV's center marker and it works well for turning
http://www.leevalley.com/US/wood/page.aspx?p=43205&cat=1,330,49237&ap=1
You could use the general idea and make something for marking with a pencil
Or buy this
http://www.woodcraft.com/product/2004363/8961/groz-steel-center-finder.aspx
or this, but I don't think it's available any longer
http://www.woodpeck.com/ottpbcenterfinder.html

He is talking about a line down the side of the dowel, not the end. You were thinking the same thing I was until I read the post again.

[Keith Hankins]

I'd use a simple jig. Take a square piece of scrap drill three holes on the center line of the piece. in the two outer holes put a round piece of dowel of your choosing. In the center put a pencil. Place the jig over the dowel and twist till each end dowel contacts the side of the cylendar(dowel to mark), and then the pencil in the center will be ligned up dead over center. Same principal for a jig for a router brace to put a slot mortice dead center in a piece of stock.

272431

[Bill Huber]

I'd use a simple jig. Take a square piece of scrap drill three holes on the center line of the piece. in the two outer holes put a round piece of dowel of your choosing. In the center put a pencil. Place the jig over the dowel and twist till each end dowel contacts the side of the cylendar(dowel to mark), and then the pencil in the center will be ligned up dead over center. Same principal for a jig for a router brace to put a slot mortice dead center in a piece of stock.

272431

You would need something to keep the dowel from twisting or you line would not be straight.

[Keith Hankins]

You would need something to keep the dowel from twisting or you line would not be straight.

yea, made that assumption, but did not draw it in. How's this?

272441

[Roy Harding]

My son and I built model rockets when he was a youngster. We often had rockets with upper and lower fins and needed to draw the lines along the body tube. We used the stop on an interior door frame as our straight edge. Never had an out of alignment fin that way....

Bingo. Exactly what I was going to suggest - with exactly the same history behind it!

It works perfectly. It's simple. You don't need to build a jig of any kind (simple OR fancy).

[Dave Richards]

And you could do this at the tablesaw or router table against the fence or if the dowel isn't too small, put it in the miter gauge slot. If you look around the shop you'll surely find something to use without actually making a jig.

[Dave Cullen]

My son and I built model rockets when he was a youngster. We often had rockets with upper and lower fins and needed to draw the lines along the body tube. We used the stop on an interior door frame as our straight edge. Never had an out of alignment fin that way....

That brings up memories. I made model rockets too, and laid the body tube along the rabbeted inside edge a desk drawer. I think I got that from an Estes rocket builders handbook.

[Dave Norris]

Hi Folks,
All excellent ideas. For my purposes the door frame will work perfectly. Very good replies too, thanks!

[Don Jarvie]

Any particular reason for this? Maybe an interesting way of doing it.