# Van Norman Boring bars?????



## Tamper84 (Sep 18, 2013)

I have been researching engine machinist work lately(both full size and scale models is where my interests lies), and came across Van Norman boring bars. There are several YouTube vids of them running but really no instruction on setting up/actually using them. 

In different forums/videos I have seen them on use on the floor, fixed to the back of a Bridgeport, and on a speacially designed table. They appear to be pretty versatile. 

What would be the advantage of using these to bore a block over a standard vertical mill? I'm guessing they have more travel then the spindle of a mill but I'm not sure.  Anyone here own/run one that wouldn't mind doing a little tutorial about them? 

Thanks,
Chris


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## Tamper84 (Sep 19, 2013)

Well I guess that to be a no lol. But for anyone else that is interested in the subject, I just stumbled across this video. http://youtu.be/HShR1r0vVl4  It is about the most information I have found on them. 

Thanks,
Chris


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## Tony Wells (Sep 19, 2013)

Never ran a VN, but have a Kwik-Way. I think the main advantage would be the travel yes, but some of these automotive machines can bolt to the block and be pretty close to square with the bore, which is a plus on vee engines, or any block that would be awkward to mount to a table. I have bored jugs for H-D's in a lathe, using a plate for a case fake, and that works too.


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## Tamper84 (Sep 19, 2013)

Thank you Tony!!! So you just bolt them to the block and center them up on each bore correct? Doesnt seem that bad lol.

Thanks,
Chris


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## rgray (Sep 19, 2013)

I have 2 VN bars and a rottler. I have had them ten years longer than I have had a lathe or mill. They have an apprx 12" stroke. One of my VN's is set up on a 1 3/4" thick plate that is surfaced on both sides. It is bolted on with allen bolts right into the base of the machine, there is a 3.5" hole that it is centered on(guess what cut that hole). Small cylinders can then be clamped up to the bottom surface, centered by the bar and then bored. Works good on motorcycle,snowmobie, and small engines that will fit into it.
I usualy use my rottler on automotive engines. I set it right on the deck of the engine (head surface)It is old but very stout and accurate. It has a 2.5"+ shaft. My Van normans have 2.2" and the other 1.8" boring shaft.
Lots of old chevys and Fords out there 4"+ bores...expect to cut within a .001 easily...From the boring I've done on a mill it seems much harder to hold that tollerance.. maybe that is easier on the larger diameter??? seems it would be harder..


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## Tamper84 (Sep 19, 2013)

Thank you for the info and the picture Russ!!! I appreciate it!!!! 

Thanks,
Chris


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## Al_T (Sep 20, 2013)

I used VN portable bars for years. They are great! I bored thousands of cylinders with them. I used the Quickway FN bars as well but always had a soft spot for the VN777 and the smaller 944 What was cool about he VN bars are the expanding "paws" They stabilize the cut in the cylinder and are very accurate for a portable bar. Many automotive machine tool companies made stands but just bolting to the deck for most applications worked fine. There is just a round bolt that screwed into the head bolt hole, slide the bar over and center with the paws tighten the bar down and start cutting. Once the paws were in the cylinder you expand them to stabilize the bar to the bottom of the hole. I always would hone at least about 3 to 5 thousandths out for optimum surface finish on a power stroke hone. But this was just for finish, the dang holes were always strait with very little if any taper with the VN bars. 

The Quickway bars became popular because they were faster and they would extract under power where the VN bars you had to crank out of the cylinder. Not a big deal. The VN bars were a bit more compact then the Quickway bars.


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## rgray (Sep 20, 2013)

If you're buying one be sure the tool kit comes with it. I have seen these tool kits sell for as much as an entire boring bar on ebay, the micrometer alone can bring $600.00.
If you get one with out the micrometer all is not lost. My rottler had no tools with it when I got it and I made a setting fixture out of some steel and a dial indicator. The indicator remains dedicated to the fixture bolted to it. You then begin the process of boring and writing down indicater readings vs size cut. It's more delicate than a mic but works good. I keep it in a foam lined box.


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## Cal Haines (Sep 20, 2013)

How do you center these portable boring bars up on the hole?  Do you have to loosen the clamp bolts and slide it around until it's centered, or does the boring bar have a way to displace it relative to its mounting plate?

What do they sell for on eBay or Craigslist?

_Cal_


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## Tamper84 (Sep 20, 2013)

They seem to sell around 800-1000 bucks. At least with the tool kit, and from what I have seen. I think this will be on my list after a mill :lmao:  Thanks for all of the great info on these!!!

Chris


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## rgray (Sep 20, 2013)

Cal

The bar has expanding "shoes" that are extended out to center the machine before it is clamped down. The Van Normans have changable "cats paws" they call them, that are different sizes for differing bore sizes. They need these cause the fixed ones have a limited expansion range. My Rottler has three "fingers" that extend out of the bar to center it, handy cause there is no changing "paws" for differing bore sizes. It has the larger diameter bar where this can fit.


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## Rbeckett (Sep 20, 2013)

I can just imagine popping the heads off a SB chevy and dropping the pan. Punching out the cylinders, dropping in new pistons on the cleaned up rods and bolting it all back together with a fresh valve job.  Brings a whole new meaning to doing and "Inframe".  Probably much quicker than pulling the engine, tearing it completely down, hot tanking, painting, boring, honing, pressing rods, replacing cam bearings, rebuilding the heads and putting it all back together again.   I can see at least 10 hours and maybe more just avoiding pulling the engine to begin with.  I'm definitely interested in keeping an eye out for one laying around in an old garage or barn somewhere.  With all the machine shops closing due to the economy it should be possible to find quite a bit of stuff like that around, here and there.

Bob


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## GK1918 (Sep 20, 2013)

Rbeckett said:


> I can just imagine popping the heads off a SB chevy and dropping the pan. Punching out the cylinders, dropping in new pistons on the cleaned up rods and bolting it all back together with a fresh valve job.  Brings a whole new meaning to doing and "Inframe".  Probably much quicker than pulling the engine, tearing it completely down, hot tanking, painting, boring, honing, pressing rods, replacing cam bearings, rebuilding the heads and putting it all back together again.   I can see at least 10 hours and maybe more just avoiding pulling the engine to begin with.  I'm definitely interested in keeping an eye out for one laying around in an old garage or barn somewhere.  With all the machine shops closing due to the economy it should be possible to find quite a bit of stuff like that around, here and there.
> 
> Bob



I machined up a mill jig special for V8 flatheads, T's and A's are easy.


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## Al_T (Sep 20, 2013)

I did many a boring job in frame on fork lifts. Saved a bundle of cash in tear down time. The 777 was remade by Peterson machine tool and it was called the PK447. The parts would interchange between the 777 and the 447 Peterson is no longer the company it once was and far as I know does not sell the bar any longer. It was identical to the 777 and built in India brought over went through and put an American electric motor on it and went from there. They were very good bars as well. What was nice about the VN bars was they were very compact compared to others. But I can tell you doing an in frame bore was a nut buster without a hoist or something to lift the bar in and out of the frame. 

To center the hole you expand the "Paws" in the cylinder center the bar and then clamp it down. Put the cutting tool in and let it rip. Once the paws are below the lip of the cylinder you expand the paws back into the cylinder and has spring tension on them and it stabilizes the cut the rest of the way down. These bars just worked and worked well.


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## Cal Haines (Sep 21, 2013)

I'm still having trouble visualizing this.  What expands the paws and how are they kept concentric with the bar?

_Cal_


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## Al_T (Sep 21, 2013)

Cal, at the top of the bar is the knob that expands the Paws into the cylinder. The paws do not rotate only the bottom of the boarding head that holds the cutter holder rotates.  The purpose of the Paws is two fold. Center the bar and then stabilize the bar as it goes down the cylinder. The paws expanded into the already board portion of the cylinder keeps the bar from wondering and keeps it strait as the paws drag down the bored section of the cylinder wall. Really a simple effective idea.  They were always known as the most accurate of the portable bars.


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## Cal Haines (Sep 22, 2013)

OK, so something like a cone forces the paws out?  Are they spring loaded?

If I understand you correctly, the distance from the paws to the bit on the boring bar is constant?  As the tool is fed in the paws are also fed down the bore?

I remember reading about building your own boring bar in one of the "Machinist's Bedside Readers".  I don't recall that his machine had the centering paws.

_Cal_


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## Al_T (Sep 22, 2013)

Cal, 

Having never torn a VN bar apart I am not sure how they expand could be a cone inside but I do not know. The knob at the side on the top of the bar is what advances and retracts the paws. Yes the paws are a fixed constant distance from the rotating cutting head which is the bottom of the bar, and the paws go down the cylinder wall as it is boring the hole. Like I said before the paws serve two purposes. The first is to center the bar and the second is to stabilize the bar as the bar is boring the cylinder.


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