Van norman boring bar questions

Hi!

I found a solution for my last question regarding my boring bar, but as i go forward i run into other things as well so instead of posting another thread regarding this bar i took the freedom to edit this first thread.

So here goes, ive started testing my bar now and i think it runs great, but the motorcase got a little hot, at least hotter than other motor equipped tools i have, i meassured outside the casing and i got about 40 degrees celcius on the surface, this was during a low speed, low feed cut of 0.015" in a smallblock 350 chevy, is this normal temperature? I have just tested this on one cylinder and i will clean it up and make an oilchange before further use because i dont know its previous history, other than this is a quite old machine.

Does anyone have recommendations for how much to cut at the time when going 0.030" over for instance? How much cut is to much in each pass?

Ive made a temporary solution for clamping down this bar but im waiting for a used kwik way boring bar table to put the machine on.

Im going to rebore a 1938 gm six cylinder so i made an improvised clamp with an aluminium roundstock, an m14 threaded bolt and a stainless steel bar with a nut welded to it. Any thoughts about this solution?

 

Here is the Ebay link to what the foot clamp looks like 320643102888

I'm thinking that you use the foot clamp to hold the boring bar down in and adjacent cylinder.

There are also several manuals for different Van Norman boring bars listed on Ebay if the bar didn't come with one. you will want to practice on a couple of junk blocks before you tackle a good block to make sure that the machine is working right and you figure out how to adjust the cutter head right. The one I had had the shaft bearing pretty worn out and they are "precision" bearings meaning that they are selected for having very low tolerances and can hold the shaft exactly in line with the machine working.

 

Thanks for the link i just bought a manual from ebay yesterday, hoping for some pictures so i get more ideas of how to fab something. ive got a couple of chevy blocks, one that needs a sleeve so ill start with that one when i get to it

 

Updated the first post with more questions and some pictures

 

pogona,

you should have no problem cutting .025 to .027 at once depending on how much you enjoy honing. Opinions vary on how much should be left for honing but it looks like you're getting a nice finish so far. We typically did .030 overbores in one cut, .040 and .060 in two cuts. You could probably take bigger cuts yet if boring for a sleeve, but you don't have to.
When doing it for a living you try to do it faster for obvious reasons.

You might want to experiment with a fast cut followed by a slow cut at the same cutter setting to see what it removes on a "skim" cut.

Anyway, enjoy yourself and be safe. I wish I owned a boring bar...and a guide and seat machine...and a hot tank...and, well you get the picture

 

Thanks for your reply 54nomore

I was actually quite amazed by how it turned out the first time. I have all the time in the world because i work in the north sea so this is just a hobby, not hoping to get rich on it, but maybe get the money to invest in a valvegrinder, bigger lathe and so on i will keep experimenting with the bar and post some pics as i go

 

I know thats most likely a test block, but never boar with out main caps on tight. Just saying.....

 

Thanks bootleggerjim, i actually didnt think of that but now that you mention it i can see why this is a good idea.

 

Use an amp meter and check you draw against the spec plate. If it's not pulling to many amps check for an internal fan problem.

 

Nice job with the hold down,and sunbeam is right on with the amp probe.
This will tell you if the machine is happy cutting the dialed in amounts.
Looks like you are expanding well in the rebuilding end of things,curious on how you are finishing the cylinders.
Depending on the hone process you can dial in your boring bar to make short work of the finishing.
I use to leave .008-.010 when I finished with a an style hone. Sunnen hand held and a big drill with a over head spring to aid stroking. Take your time and good results can be had. Lots of time.
Some folks bore up to .001 of finish size and quick hone to finish,IMO and many others this leaves tool marks and greatly reduces ring life.
When you and your boring bar have a relationship and understand each other you will find the way that works for you.
There not just tools,somehow they all have personalities.
Like said torque main caps to pull on block and use a toque plate when you can.
I have torqued wrist pins as a attempt to draw on the deak surface and had measurable changes happen

 

Thanks for the replies guys, i knew this was the right forum to ask

Im going to check the current draw when i can find my clamp amp meter (electrician by trade but put those tools away when i became an rov pilot, was hoping to never use those tools again hehe)

The bar actually seems to work quite well, so she is going to get some fresh oil and grease today, and maybe some brushes for christmas if she continiues to behave like this. Anyone know who supplies brushesfor the motor?

As for the finish, i have an Sunnen An hone i got for free so i bougt a couple of sets with new stones, any suggestions on the finishhone regarding stone grit?

Im planning to make a tray on the kwik way 054 table when i get it with an oil pump and tank and som kind of filter so i can hone with the block the same place im boring because i dont have to much workingspace around me. I also have an idea for an automatic operated pneumatic drive for the hone with adjustable speed and stroke, but ill leave that for another thread when i get to it. Been planning to make a project thread but i realised ive been doing a lot more work in my workshop than on my nova lately so any updates would probably be about organising the shop and building stuff not related to the nova and boring to read anyway.

 

I had an old storm-Vulcan, I used to cut .015" and then another cut to get to the finale .028" or what ever you want before honing.kept the motor from getting too hot. also wait awhile before you start another cylinder.

 

Just wondering how do you know that you are boring the cylinders straight and not at a very slight angle ?

Do you check that the deck is straight where the boring bar mounts ?

Just wondering what it is squared off of or lined up with?

 

I tried to meassure my bores using a stainless steel axle clamped along the main bearings and a machinists angle in the bores and a set of feeler blades but i couldnt meassure any angle of the new bore.

My main concern was discoloring and slight pitting on the bottom of the boring bar when placing it on the block but its pretty clean and seems straight. Another concern i had was wether to surface the block before or after boring, so far ive just scraped the gasketleftovers on the deck and sanded slightly with fine grit paper until the deck feels smooth and even.

 

Because i thought it would be an idea to save the decksurfacing until after im finished sliding and clamping the 60kg boring bar along the deck.

 

I have a Kwik=Way and a Van Norman boring bar. I use the K-W most of the time as it has multiple speeds and can cut large quantities at a pass. But I like the Van Norman for it's cut Quality. Only .025-.028 per pass but the finish is almost mirror perfect. A lot has to do with the cutter profile. Which is different for rough cut and finish cut. Also different cut angles between the machines. But the VN is just more consistent..

The supplied clamp system for either machines consists of an upright unit that goes in adjacent cylinder and a clamp mechanism in the machine base.

I use a system close to yours when doing large diesels.

Also used is a bolt in fastener that threads into the deck, threaded head bolt holes. Then slides into the base clamp. This piece is also used on boring fixtures to clamp the bar to the top plate.

Goodson or Silver Seal in Trenton Mich. are good places to buy the correct cutters etc.

As for motors, my model K-W uses several different motors depending on year of manufacture. As far as I could tell the Van Normans are the same thru out each different models.

 

This method has been used since engines have been casted,not to say it is the best though.
A rottler has a cradle that carries the block and cuts 90degrees to the mains.
This is the caddilac of boring systems.
I for one do not have this.
But I do have a storm Vulcan 85b block master and I use a bhj bloc true fixture that squares the decks to the cam/main bores.
After the decks are square and true I bore off the decks to square it to the mains.
This also allows me a point to measure to to achieve my desired deck height without a mockup assembly.
A real time saver.
If you were to really measure a stock block you would be shocked how far they are really out.
To date my worst has been a 360 Chrysler,.035 removal before the decks were flat.
When I used a an hone I would use 100 grit after bore until I was .004 to finish,300 grit until .002 until finish then to finish with a 500 grit.
Remember an grits are different than ck styles.500 is about a 320 finish.
If you invest in a set of pleatu brushes( a tad pricy for a an hone) it's money well spent.will give you better than a 15 ra finish and your rings will love you for it.
Hope this all helps.

 

Any inputs on cutter profiles? Im currently cutting with a pretty sharp cutter i think, it has 45 degree angles towards the tip and the tip is about 1 mm wide where it cuts, is this anything i should change?

 

Is this a machine that was made for USA use? If so the motor was made to run on 60 cycles(hz) I think you guys run power at 50 cycles(hz). Check motor label for info. This may cause motor to run warm

Norm

 

Nevrdun, i forgot to check today but you might have a point, i got my machine from the us and we do have 50hz here. My transformer is also pushing out a tad higher voltage than i planned for so im going to see if i can find a big enough variac or what its called instead.

Prior to boring the block i bored yesterday, i opened up the boring bar to inspect the motor and it all looked good exept for one of the wires where the insulation was damaged because of the rotor, easy fix with som shrinksleeve and a zip tie, and then i got carried away and opened up the main gear casing and the oil inside actually looked like something that could have been 50 years old, it was hardly liquid at all, so i gave it a good clean, inspected the gears and put it together again with new oil and it actually sounded different when running.

Anyway, i bored this 216 block from 040 over to 060 over, and all the meassuring and converting from inches to mm and mm to inches and different piston materials etc gave me some other questions regarding boring, like;
What guidelines should i follow when determinig clearances between pistons and bore, how much is recommended in stock builds and performance builds?
How much is to much and not enough clearance?

Today i put back the 350 block in the stand and it got me to think of the sleeve i want to try to install, any thoughts about clearance and should i hone the block before i press the sleeve in, or should i leave the bore unfinished?



Pretty happy with this finnish

 

Suggestion: Make up another bit holder with a 45* angle ground into the bit. When you remove the boring bit and holder, insert this chamfering bit and holder and manually (carefully) lower it to the top of the bore to cut a slight 45* relief at the top of the bore. Sure beats hand finishing this area with a Sunnen cone sander!

Yeh....those 360 Mopar engines are out-to-lunch with machining quality control, especially with squaring the decks with the mains.

 

Thanks for the tip, i was going to buy i cone sander but im not that steady on the hand so a cutter for chamerfing is on the to list.

 

Piston clearance is determined by the manufacturer. I usually leave the bore about .003-.005" small. Part of this decision is whether the block is going to be honed with an automatic Sunnen Ck-10 or CV616 type machine or a hand held type hone..

When installing repair sleeves.. The proper install usually requires a bore with a step at the bottom for the sleeve to set on.
This is done by boring the hole short about 1/8-3/16" then running a flat bottom edge cutter down to make the ledge flat. This also the cutter that is used to trim the top edge of the repair sleeve. After it is installed..

The hole should finished with a smooth final cut from the boring bar. As there is a ledge there is no honing at this point. Hole size is determined by manufacturer and use but a general rule of thumb on non siamese sbc blocks is .002" smaller than the sleeve.

If you are using a press you can get tighter but that only distorts the neighboring cylinders. I usually measure the sleeve in three points around the OD. divide by three. Subtract .0015-.002" and you have your hole size.

Beware, cheap sleeves usually have rough outer surfaces and are far from round. Buy quality sleeves at least 1/2" longer than your intended cylinder..

If there is no block oven available.

After the hole is correct and lubricated. Old timers use brake fluid. I use a bi-polymer sealer. I then get the sleeve. Which has been the freezer overnight. Place sleeve in hole. It will usually go in about 1/8". Place a piece of inch thick plate over it and QUICKLY drive it in with a eight lb. sledge hammer till it seats in the block.
Re center bar and trim top of sleeve to about .002" above deck. Bore sleeve to desired size, they are undersize usually about .060" then cut a minor top chamfer. Remove bar and surface top of sleeve to block deck carefully with a wide flat fine file..
BOB

 

I love this forum more and more, for every question asked here, theres a person with a answer. thanks Bob. Im using a Sunnen An style hone with a power drill for the moment but thats getting a bit heavy for the biceps so im going to make an automated setup. Ive bought some sleeves from enginetech, theyre stamped us-made and looks to be of fair quality. I dont have a big enough oven but i have a 20kw kerosene heater in the garage so i thought i might heat the block up to hotter than it is now sitting in the basement at least. And i have a freezer in the workshop for the sleeve.

Ive been trying to read a littlebit about heat expansion and i got concerned about setting the cutter because i have all my micrometers and the toolsetter in a clean and heated part of the workshop and the boring bar in a chiller part where the temp difference might be 4-5 degree celsius, could this affect the meassuring?

 

Yes, all involved pieces should be at room temp..

If you use a heater on the block. Don't freeze the sleeve. Possibility of the chilled sleeve cracking from such a temp difference. I haven't cracked one but I've seen it done.

One shop I work in uses a block oven. Makes install simple. Bore block to correct temp and put it in oven. At proper temp. roll block deck up to level and the sleeve drops right in. As a matter of fact. I have to be careful and keep down pressure on the sleeve because sometimes it strikes the bottom ledge and pops up about 3/8" and freezes,, then it's a real bitch to move down.. Ask me how I know that!!

Other shop I work uses the frozen sleeve method. This works best for a no heat system.

Also do not bore or hone adjacent cylinders till the sleeve is finished. Sleeving distorts the neighboring cylinders. Not much but it show up at the top of the bores.. 400's are the exception and very few will sleeve a 400 sbc unless absolutely have to..

When I started doing this back in the sixties.. I had the same Sunnen hone. Chucked into a Giant Thor drill.. After almost breaking my arm and several bouts with wrist sprains. I made a fixture. Two arms from the wall holding the drill. A large spring to help upstroke. and a threaded fine thread rod to limit down stroke. All mounted over a stainless milking parlor basin. Used it for years till I bought into a "modern" shop/

 

Thanks guys, really appreciate your knowledge

I got the 054 table home last week, bought it second hand in new york so it was missing a few parts but im shure ill be able to fab up the missing stuff. A friend of mine delivered to my shop with a flatbed truck and a crane so that saved me some effort.

I didnt have a clamp for the VN boring bar so i made one up myself, any thoughts about it?

I have aquired a 25mm stainless steel bar i was planning to use to hold the block mains, do you reckon thats thick enough to cope with the weight of the block? Last thing i want is movement of the block when boring.

I also got a round fixture with the table, i suspect its for a single cylinder aplication, does anyone know if thats for HD cylinders or VW? I was hoping for vw but cant figure out how it wil seat the cylinder on the underside of the table. Any pictures of this?





I also got my hands on a 427 bbc block with a cracked cylinder to practice on, but then i got to think it might be saved, i was thinking about reliefing the ends of the about 1-1/2" crack with an angle drill or die grinder to prevent further cracking and sleeve the block, any thoughts about that? My main concern is that the crack will expand further with the interference fit of the sleeve and wether or not i will get it sealed properly to keep the coolant out of the crankcase.