engine boring on a vertical mill

To all the people who say that I cannot bore a engine block with a
vertical mill, let me ask you this:
Why cannot I bore a engine block with five inches of diamator and six
inches of depth with .001 accuracy in both its horiontal and vertical
plane?
Can I purchase a longer quill and still mantain accuracy?
Can I purchase a tool which will allow me to by-pass the spindle and
attach my boring bar directly to the quill and still mantain accuracy?
Don't get me wrong' I am not a expert, but I am not buying it.
Reply to
nattydreadlocks2001
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Hi Natty, On a dedicated cylinder boring bar there are four cats paws which expand onto the bore as the cutter is desending which stops the thrust of the cutter from pushing the quill off course. Regards Rotty
Reply to
Rotty
Then try it. What have you got to lose?
Regards,
Robin
Reply to
Robin S.
you could even bore it with a hand drill if you had the right setup. The whole thing is how rigid the boring bar is held, using guide bushings or a real stiff quill. All you got to do is to make the boring tool move through the bore in an absolutely straignt line. Its easier if you take small cuts.
John
Reply to
john
Because you're not an expert...
Reply to
Tom
vertical
accuracy?
Please be more specific Mr. Expert! If your are not out to help me please don't respond to my posts. Once again, why cannot I bore a engine block with .001 accuracy in both its horizontial and vertical planes? Are those large vertical $8,000 mills sold by companies such as Jet and Grizzly not up to the task? I would like to use a vertical mill because it come down to simple dollars and cents. A vertical mill could be used for milling cylinder heads, manafolds, cluthes, presure plates and valve work just to name a few.These specilized pieces of equiptment brought individualy are far beyond my budget. So what say the? Help, or no?
Reply to
nattydreadlocks2001
Ok, here's what you'll need to do:
1. Setup machine correctly.
2. Select appropriate boring tool (insert and holder, or brazed toolbit, or bar and HSS tool), grind (if req'd) and setup correctly.
3. Select appropriate feeds and speeds for roughing and finishing.
4. Setup block correctly.
5. Machine cylinders to dimensional and finish specifications.
There. No problem.
So how many dozen factors must be considered to do the above correctly. Also, how much will it cost you if you're wrong?
There's a reason people are paid to do this stuff. However, if you feel confident, you should go for it.
Regards,
Robin
Reply to
Robin S.
Correct you are. But then again, I thought that was the whole primis of this thing; to get help, give help and to trade ideas. To be quite honest, I don't believe that you have the necesary skills either. Reason being, you haven't answered any of my questions. With that, I humbley ask that you not answer any more of my posts.
Reply to
nattydreadlocks2001
Thank you for your reply. The only problems I foresee running into are steps two and three. Do you have any more insight on these two steps? The cost to me is zero if things go wrong. I have about twenty cast iron engine blocks on reserve totaling 160 +/- holes to practice on. The thing which worries me is dropping $10,000 on the cost of a new "multipurpose" machine and tooling and it not being truely "multipurpose".
Yes, their is a reason why people are paid to do this stuff. The reason is: others are afraid to try new things.
Reply to
nattydreadlocks2001
My older brother bored out his 350 with a (IIRC) 9x42 Bridgeport with 4" of quill travel. That was umpitty years ago and it is still running. He does know his stuff, I don't think I qualify as his shadow.
Wayne
Reply to
Wayne
snipped-for-privacy@yahoo.com wrote in news:1104715718.576831.202440 @f14g2000cwb.googlegroups.com:
Or, in this particular case, they know and have what is needed to do the job in an accurate and efficient manner. In addition to what Robin stated, you will need to: a) design and build an accurate and rigid jig on which to mount the engine block. b) determine what all this weighs (jig + block) and determine if that will exceed the table capacity for the machine. c) determine if (the weight is close to the table capacity), what deflection will occur on the table because of the weight, and then find a way to correct for that.
** ASSuming a b-port type machine here.
Reply to
Anthony
Wow, great way to win friends and influence people. I'm sure that your attitude will make many others want to try to help you with _your problem_. Not.
Reply to
Dave Hinz
Once again, you obviously don't have the necessary skills!
Reply to
Tom
You're right, a "vertical" mill is the bee's knees for boring engine blocks, anyone who says different, doesn't know how to waste time and get a lousy return on money invested. Engine reconditioning shops in your area better look to sharpen their pencils.
Reply to
Tom
Thanks for all of your help. I still insist that it can be done properly and in a timely manner. Peterson Machinary sells what basically is a huge vertical mill, jigs and tooling to do exactly what I am talking about. The only draw-back is the $80,000 price tag. Were thier is a will, thier is a way!
Reply to
nattydreadlocks2001
vertical
accuracy?
I beg to differ, I have bored cylinders for 30 years with various machines and what you are referring to are the centering jaws which work like 3jaw lathe chuck jaws to center the boring bar in the cylinder. The boring machine, which is setting on top of the block is clamped down and the jaws retracted before boring. Engineman1
Reply to
engineman1
Ill be glad to sell you a Sizouka Horizontal/Vertical mill for $5000 or best offer
The table travel is just big enough to set up for horizontal boring.
Located in So. California.
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Gunner
It's not unwise to remember that Mother Nature is essentially a murderous, sneakly, promiscuous bitch who has been trying to kill you since your conception.
Eventually she will succeed, perhaps with the help of your fellow man.
Life consists in putting off the inevitable as long as possible and taking what good and joy you can before her success.
Whether you attribute that situation to evolutionary forces, a fallen nature after Adam and Eve screwed the pooch, or whatever, it's no less true.
Be friendly, pleasant, unaggressive, and honest toward all and be prepared to ignore, avoid, or even kill anyone who is otherwise toward you. Being ready doesn't mean eager, just ready. What true friends are found in life will undestand and accept that fundamental rule of human interaction." John Husvar
Reply to
Gunner
Yes, you can do it, but not quickly. This mill has the 6" riser block installed and a power knee feed. This would probably be about the best setup for a Bridgeport type mill to bore blocks. It's still not a very good setup to do blocks. You still have the problem of the knee rocking because of the heavy weight of the block. When you move the table from left to right. That means you will have to shim the block for about just every hole.
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A block machine is built almost like a bed mill. The table is fixed, so there is no rocking of the table. Link of a picture of a BPV-B2V Manual Bed Type Mill
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This bed mill still has the weaker Bridgeport type head, but because the rail that the head is mounted to goes up and down. It's not limited to the 5" spindle travel.
If I understand you correctly you want to do this for a living. Boring bars for engine blocks are specialized machines. Designed for quick set up. The last guy I spoked to in an automotive shop shop said he could bore all 8 holes in under 45 minutes. On a Bridgeport type machine I would guess you would have over 8 hours in it. A guess on my part since I have never done one in a Bridgeport. In today's paper Schucks is selling a 305 chev long block for $799 exchange. You are going to have about 1/2 of that tied up in labor just boring the block and you still have to hone it.
Automotive shops have deadicated machines so they don't have long setup times. Also one person runs 2 to 3 machines at the same time. You can't do that with only one machine.
No! At least I haven't seen any with over 30 years in the trade. The reason is in order to increase spindle travel. You must make a longer spindle. The housing that holds the spindle must be made longer and the casting for holding the spindle housing must be made longer. Also the handle for raising and lowering the spindle must be moved down for the extra travel. In other words you need to cast the lower portion of the head. Machine it and make a new spindle and housing.
The answer is no.
You are looking at a Bridgeport machine to do everything with and it's just to light of a machine to do block boring and head work. A Bridgeport will do light drilling, but it's not a head machine. To face the head you will have to fly cut it, (1 cutting tool) the head/block surfacing machine has a multi inserted facing cutter. (Often 8 to 10 cutting edges) So it's much faster and more rigid of a setup. You really need all the specialty machines to compete in this market.
If you are just messing around in your garage, then time means nothing. So just have fun.
Richard W.
Reply to
Richard W.

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