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Hello guys. This is a simple boring bar I made up to use for a pulley I needed for the lathe I'm working on. The pulley was made of 6061 aluminum. I used an insert I had on hand for this. The bar chattered quite easily, so I don't think the geometry was correct but I went real slow and it worked. A narrow v block was made up to help with clamping.

Block layout:

[Image: boringBarBlock.jpg?dl=0]

Finished block:

[Image: finishedVblock.jpg?dl=0]

V Block fitment:

[Image: vBlockFitment.jpg?dl=0]

Starting bar cut with dial indicator to use for the starting point of each pass:

[Image: startBarCut.jpg?dl=0]

Bit base cut. A 20 degree angle was also cut for the bit side face.

[Image: barCut.jpg?dl=0]

Tap bar:

[Image: tapBar.jpg?dl=0]

A couple of views finished:

[Image: topBar.jpg?dl=0]
[Image: sideBar.jpg?dl=0]

That's all.

I have said it before, I'll say it again; I gotta get me a shaper.
Very nice job Mark.
Yea Pete O, I feel ya! When I went to get the lathe from a guy on Kijiji (basically Craigs List in Canada), he had a bunch of machining stuff I have never seen from his recently passed dad. The shaper was one of those things. At first I thought that it was stupid and I wasn't going to buy it, but I looked it up on the net, and realized it might come in handy, so I asked him what he wanted for it and he said $125 CAD and I said SOLD. That was one of the best purchases I ever made. I use it all the time. I love it. It is my 70 year old baby! I spent a little over a thousand bucks at that guys house, and don't regret it even a little. Now I have a small machine shop.
(04-22-2016, 05:49 AM)turbo711 Wrote: [ -> ]Now I have a small machine shop.

And the enjoyment that you will get out of that is priceless.
Really nice work Mark Smiley-signs107   Thumbsup 
a job well dun
Nice work. I love shop-made tools. What material did you use for the bar?
Nice work! I especially like that style of insert. They are ideal for boring, in fact just what they were made for. The right hand version of the chipbreaker on those is something special for when you need very low cutting pressure, such as a longer small diameter bar or thin walled tubing. Valenite still offers both left and right in the TNMM negative rake style, chipbreaker designation PN-EL1 & 2 and the PN-ER1 & 2. The 1 is a tighter chipbreaker than the 2.
I'm not sure of the bar material Roadracer_Al. It is just something a picked up when I bought all the tooling, lathe and shaper at the same time. I just grabbed all the various stock I could. The gentleman was clearing his mothers basement and was eager to get rid of it.
The type of steel has virtually no effect on a boring bar. They all have the same modulus of elasticity which determines their stiffness. Tungsten Carbide on the other hand is about 3 times stiffer. I have a few of those inserts and also made a boring bar to use them. They eat metal for breakfast.