Machining 70 degree angle

[JeffinWI]

Hanz, by biggest concern would be measuring the "way" angle accurately and then duplicating that angle when tilting the head. I wouldn't worry too much about rotating the part to cut the 2nd side of the "V". Assuming you have a machined suface somewhere on the "face" of the steady rest, that you want your "V" to be square to. Indicate that/those surfaces in, and cut one side. Then turn the part 180º and re-indicate those same surface in again, and cut the 2nd side. If the indicating surfaces are not widely spaced enough to make you feel comfortable, clamp a good straight parallel to them and indicate that. Easier, IMHO, than tilting the head the opposite direction and tweaking the angle exactly the same again. Parts are done this way in job shops every day, for bearing bores, etc., on opposite sides of large frames, etc. that MUST be in line. Many times they can't be bored through for one reason or another. If indicating surfaces are lacking, "set-up cuts" or "reference marks" are milled to allow indicating.

[Ralph_P]

Hanz,
I bought a S/B 13" steady and remachined it to fit my 12" Clausing. I removed the top half, then mounted the base upside down on the mill. After squaring the V up to the table I milled 3/8" off the base. This removed most of the original V. I centered the spindle where the new V needed to be, then using a 1/4" end mill, cut a groove about 1/16" deeper than the V needed to be. Using a sine bar I tilted the mill head and cut one side of the V using I think about a 3/8" end mill. Then tilted the head to the other side and cut that side. The 1/4" grove in the bottom of the V gives enough clearance that the end of the end mill dont make contact on the second side cut. Look at the V on your tailstock it's made the same way.

(trying to add pic.)

[metalmite]

Hanz,
Smile, life is good!
You look like a grump in your photo.
Life ain't that bad is it?
I have confidance a mechanic with your toolmaking, amd machining experience can work this one out.
Metalmite.

[fredwhite]

I could be wrong, but I thought the angle on a Clausing 59XX series was 60 degrees.

[Hanz]

Hmmm...I measured it a couple months ago, I will certainly recheck it before starting. Thanks

[Matt_Isserstedt]

But I cut a 70 degree groove last night with the shaper.

While my slot was over-wide (but still 70 deg) I could visualize a perfect parallelogram in the open space. I'm going to make a smaller slot today to verify my technique and fit before proceeding.

[Hanz]

I just checked- definately 70 degrees. Matt- my latest plan is to spray weld up the current 90 degree V, so that I can go ahead with milling the needed V and not worrying about interfering with the current wrong one. Spray weld is soft and easily machined. Hanz

[Harold_V]

Hanz,
Assuming the steady is made of gray iron, The juncture of the weld with the iron may come out harder than the hinges of hell. You may have to do an anneal process on the steady. I'd enjoy hearing how this process ends up.

Harold

[Matt_Isserstedt]

Did you just indicate the round casting ID of the steady with an indicator in the chuck/collet?

On the roller bearing steady, I planned to first setup the v-groove and then mark a center point with a center in the headstock, and then pick this up for the bearing bores...

Anyway, I've got the same issue with the steady rest, I did consider shaping/milling out an oversized rectanglular slot, then bolting in a tight-fitting piece of steel (perhaps hard) with the 70 degree V.

Keep us posted!

-Matt

[Hanz]

Well Matt, first we realize that this does not have to be and cannot be the most accurate dimension, since the fingers are adjustable and are only meant to barely rub on the workpiece. So I will close the fingers so they seem to be even, on an appropriate piece of stock with a point on one end, with a diameter that fits the radius on the ends of the fingers. I will set the steady on the way like I already have done and compare the height to a center either in the chuck or the tailstock. Point to point holding a scale next to them I can visually estimate within .010 or so, and I believe that is well within tolerance for that dimension, and I will do the same for the lateral. Then it will be easy enough to diagram the height and V location.

[philinmt]

I think what Hanz is refuring to is using spray power to build the vee. I done this for years with out any hard spots, also there is good cast iron weldind rod on the market now that will give good results(not the cheap nickel rod that is called cast iron welding rod...this stuff runns $50 to $100 a lb) ...Phil in Mt

[Harold_V]

Phil,
You're telling me you can build up cast iron and not have hard spots? If so, that's really cool. I've seen the spray process only one time, many years ago. I wasn't aware it could even be sprayed on cast iron, let alone not have it harden on you. How well does it bond to the iron?

Harold