A centre finder

[powderpost]

Here is another gadget that has been around from before the ark was built. It is made from a bit of 250mm x 38mm x about 300mm long, and some 15mm square stock. Equally a bit of 19mm ply will do the job. The 15mm square stock is cut to form accurate squares, with a spike in the centre. To use it, rest the timber on top of the spike, rotate the timber until the four corners touch the side of the square and tap the wood gently. The spike will mark the centre.
Before retiring, I turned a lot of 100mm square table legs, 75mm square coffee table legs and 50mm square chair legs. Because of that, I made the squares 5mm larger both ways, for each size. Later I added a small one for needle box blanks. The 45 degree 'line' is in fact a hacksaw blade glued into a groove with the back of the blade sharpened to a knife edge. We often have a bit of round stuff cut off from a turning without a centre. If the round is placed in the 'corner', with a tap, a diameter is marked. Rotate the piece about 90 degrees and tap again. Where the lines cross is centre.
Certainly not my idea, but have been using it for many years.
Jim

[coffenup]

great idea have to make one for my self. took 5 mins to make the centres as a learner i see the benifit of this type of jig

regards Michael

[funkychicken]

I reckon that's brilliant:2tsup:

[oldiephred]

Sorta off subject but not entirely: Finding the center of irregular shapes was a particular problem for me so I made a perspex centering tool. Probable a very old idea but I don't get out much.:U Actually I firmly believe that the center moves between the time it is marked and when it gets to the lathe.
I attached a piece of 6mm clear perspex to my faceplate and put it on the lathe, marked the center and scratched a series of concentric circles about 10mm apart from the center to the outside. Drilled the center about 2mm dia.
Placing this on the end of a work piece one can find the circle that best encloses the end of the workpiece then mark the center through the center hole. It can be dressed up a bit by coloring some of the rings with fine felt tip markers to reduce errors.

I appreciate the ideas I see on this site.

[barnsey]

Gee - did I miss something somewhere??

1. Combination Square for square stock,
2. V Square for round/irregular
3. Sharp roughing gouge
4. Sharp Skew

Why do I need a jig?:?

OK maybe if I want to do 30 pieces at a time but 3 &/or 4 will more than compensate for inaccuracy in 1 &/or 2 in general.

Large dia's need better accuracy so you don't throw em at yourself :B I guess!

[rsser]

It's about speed burnsey.

[oldiephred]

Not really a debater BUT it seems to me that before using a gouge or skew to find a center one has to decide where to pace the faceplate, chuck, drive dog or whatever?
Anyway differing opinions are what make the world interesting--- sometimes:;

[hughie]

Finding centre is not really a major issue for me. I do it by eye and near enough is good enough for me.

Plus or minus 1/2" or 10-15mm is not problem. Irregular blanks will eat that up anyway, round blanks, well they are fairly easy to guess a centre point.

[TTIT]

Gee - did I miss something somewhere??

1. Combination Square for square stock,
2. V Square for round/irregular
3. Sharp roughing gouge
4. Sharp Skew

Why do I need a jig?:? ...................................
Pummels (transition from square to round like on table legs) look pretty cruddy if you don't have the centre spot on! Jim's jig is ideal for getting them right.

[Frank&Earnest]

Somebody (oldiephred?) posted a picture of the clear plastic solution a few months ago and I jumped on it - it seems to me the easiest, quickest and most effective for irregular blanks, but to everybody their own, I guess.

[rsser]

Pummels (transition from square to round like on table legs) look pretty cruddy if you don't have the centre spot on! Jim's jig is ideal for getting them right.

Pommel.

All my pummels are rough :wink:

[jimbur]

For small split stock I even use a plastic bottle top with a hole in the centre. It's just a matter of what's quickest and suits the job in hand.