Cutting Points - up vs down, climb vs conventional

[BarenbruggeCues]

Sorry, after I read that statement that I wrote I realized that I should have said "Diekman, as you are probably aware". The film I had, on building points, was purchased in 92 or 93 from Dennis. He had the set-up in a lathe, not a mill however. He had a bracket made that held the router at a 45 deg. angle using a 5/8 straight router bit for cutting V grooves. This was mounted on the compound. This arrangement will work well as long as all movement from vibration is eliminated. I used to cut my V's on the lathe but I used a 90 deg. V cutter and went straight in from the side. This is a poor way of doing it I found as the very bottom of the V doesn't get cut sharply because the very bottom of the bit is innefficient. The way you are considering and using a router bit where the outer circumference is in motion so that the bottom of the V is cut cleanly are, by far, the best solutions although there are, I'm sure, many others. The nice thing about your set-up, although more difficult to build the jig, once done, the bits are much cheaper and easier to find.

Dick

I have to agree.........and besides all that..it gives you other options you can't have using a v cutter.

 

[BarenbruggeCues]

Dave,
Too bad Chester has gone away, he could spend two days telling you how to set up the sine bar. Comes down to length of the sine bar, then I believe it's the cosine of the angle you want to use that determines the height of the blocks you put in. Pain in the butt to set up. My bridgeport tends to drift a little left and right as I crank in the angle, so not only are you working the angle of the head you are fighting to keep it square with the table. Then comes the fun of getting the cutter height correct. But all said and done, when you get it right, I believe it is the best way to cut deep points. I use a shell mill that was designed for aluminium. Razor sharp. And of course, as soon as you get it set up, along comes something else that you want to do on the mill. Picture on my website/ shop page with the head cranked over.

If you ever saw Diekmans tapes, you would die laughing, He used 2 by 4's to mount things and measured depth by counting turns on his cross slide.
Nothing like using 4 turns on the cross slide for a reference.

Getting back to climbing and conventional milling. All those articles are written for metal workers. A forearm will flex more than the cutter will deflect, no matter which way you go about it. Especially if you do it between centers, and who knows how the 4th point will react with all the wood already removed from the other 3 points. I personally think that as long as you did it the same for each point, it doesn't matter which way you do it.

He's the only reason I know what a sine bar is! That was one of many things we talked about that I didn't listen about very well.

 

[BarenbruggeCues]

A sine bar is called that because you use the sine of the angle to get the stack height for the bar. They are normally whole number of inches in length to the center line of the rollers. EG 4.000 inches or metric 100.00 mm long. You do the sine of the angle , like say 5 sine,0.0871557 then x length of bar say 4.0, = 0.34862 . This is the amount needed to be stacked under 1 end to make the angle. Then when the indicator on the top of the bar is zero the angle is correct.When using on a lathe is tricky as you need the bar to be at 90 deg. I use magnets to hold the gauge blocks in place and a stack of parallel blocks to keep it at 90 deg to the saddle.

I must have played hooky that class day in math.

 

[ugotactionTX]

What is the "A" joint?

I cut from the "A" joint out, and then back in. I don't readjust the cutter depth on the reverse cut. It is only a "cleaning" cut that basically does just that, cleans the cut surface up.

Sorry guys EXTREME newbie here. I understand most of this thread just not sure what your calling the "A" joint.

Also, could someone please tell me the specs on the double angle cutters? size, no. of teeth, angle, stuff like that. Is there someone that sells these specifically for cue building?

 

[Tommy-D]

> The math info is correct. A scientific calculator is needed though for the degree-minute-second conversion. The question is,how many cuemakers have a set of gage blocks? Fortunately for my machinist schooling,I have my own set along with a 3,4,5,and 10 inch sine bar,thanks to my departed grandfather.

The ones the shop at school provide are so worn,they can't be "wrung" properly.

My set is by Browne and Sharpe who supposedly don't make them any more,and a comparable Mitutoyo or Starrett 81pc set in AA quality like I have,is around 4k. Some of mine are still covered in cosmoline,having never even been taken out of the box.

I had to perform this task of using a sine bar to set the compound on a lathe yesterday afternoon. The taper has to be cut manually,due to no taper-bar,and the angle is 2 degrees,5 minutes,17.04 seconds. Using the method outlined above,I trigged out the angle according to the print,and adapted it to a 3" sine bar,the gage block stack came out as .1095,so I used a .1015 block and an .008 feeler gage,and got it to indicate to 0. I could have just used a .110 block,but being more anal than most,I shot for DNP. The tolerance on the part for grading purposes is 2 minutes,30 seconds. Tommy D.

 

[jspach42]

router vs milling machine.

I cut points on both my lathe and my milling machine, depending on how many I want to cut that day. Its easier on the miller but faster on the lathe. I climb cut with my router using a 90deg v bit and 2 passes toward point, but I conventional cut with my router on a taper bar on an old lathe using a 2 sided 90deg v cutter and do it in one (1) pass nearly as fast as the lathe feed will run as to not burn the wood or heat up the bit. If your burning the wood your running too slow..

Hurricane cues.