Cutting quiexxxxx nevermind #104 - Kansas USA

[JamesJ]

Looking forward to building my MechMate! I'm a avid woodworker and a passable welder with a son who welds like a madman. Looks like sonny has some welding to do.

[MetalHead]

Welcome to the group !! Looking forward to your build.

[riesvantwisk]

Welcome to the group Jim!

Browse the forum, read the PDF's, browse the forum, read the PDF's ask question... read.... you will have some fun there with your son.

Ries

[Felton]

hi welcome to the forum.

[JamesJ]

Thanks to everyone for the encouragement.

[JamesJ]

I started on my control box. I also received my laser cut parts and have machined some parts on my Logan 10" lathe. I purchased a gear blank and intend to try my luck at cutting gears out of it. I have attached a few pics...

[Drad98_98]

Good luck Jim, I just finished mine, had a great time building it. There is a wealth of infomation and very knowledgable people on here that will help in a minutes notice, it is what made my build so enjoyable.

[Gerald D]

Jim, is that a South Bend lathe?

[JamesJ]

No, it is a Logan 10" toolroom lathe. It's on the small side but I still find plenty of uses for it.

[MetalHead]

That is a sweet lathe. Did you restore it? Or was it that cherry when you bought it?

I am currently looking for a nice lathe, but I want a larger one. I have a 10x22 Grizzly that has worked great for what I paid for it.

I just want to work heavier material and these Logan and South Bend machines are a good buy if you learn what to look for when you buy one.

[JamesJ]

Yes, I did a total teardown and restore when I first got it. Nobody told me about the fact that quality tooling costs many times the cost of the lathe. I might not have one if I knew ahead of time.

[Regnar]

Jim we have a 10x54 Clausing Lathe at work and I bet it has never chucked up anything over 10 inches. If you did the restore you it turned out great. I am almost finished rebuilding a old Bridgeport Round Ram. I am just waiting on the motor to get rewound.

What is your plan on chucking up the gear stock?

[JamesJ]

Haven't thought about it much. I have a 6" 6 jaw that might work if I use some shim stock. Or maybe just center it up in my 4 jaw. Do you have any ideas?

[JLFIN]

Jim,
welcome and good luck
bit of advice for ya, 4 jaw will work to dial that blank in, take some old copper wire and strip it back about the length of ea. jaw and slide that baby down the teeth and chuck away. 3 or 6 jaw wont hold it concentric because of the 20 teeth on blank.
another way is to bore out a heavy walled pipe, slit lengthwise then chuck back up on it
carefully bore to the dia. of blank, when you release it should let you slide the blank in to the sleeve and you should run centered( mark the jaw of the chuck and the sleeve with marker so you can return to the same place in the chuck) kinda wordy for me

[JamesJ]

Jim
Thanks for the ideas. I am going to try the wire method and see how close I can get to concentric. I used the slit/collar method to cutoff the excentric bushings so I may end up doing it that way if the wire method does not work good enough.

[JamesJ]

Jim
Are you building a MM?

[JamesJ]

Anyone have a US source for the c channel washers shown in this thread on the second page most of the way down?

http://mechmate.com/forums/showthread.php?t=1385&page=2

[OBXCNC]

McMaster-Carr has the washers

http://www.mcmaster.com/#washers/=664vff

[MetalHead]

Jim - Most folks make these. You can drill holes in the wing of a c-channel drop then use your grinder to cut them out. Turn them around and you have a washer that matches your channel.

http://www.mechmate.com/forums/showt...7&postcount=32

[JLFIN]

Jim- I have not started mine yet, I'm still in the procrastination stage.(design stage)
I've logged about 200 hrs of thread reading and decided I'm not to smart!!!! There are some folks on here that are. Speaking of design, I'm considering the use of ball screws, possibly one on each side for x-axis, driven by one motor located in the center, with timing belts to each side, driven by a 3 or 4 to 1 reduction, can I have feedback on why that won't work, also I really liked the builds done with I-Beams, seams a little stouter to me.

[JLFIN]

Russel, is that old mill called a "M" head, I think I owned one once upon a time but it seams to me the collets were hard to come by?(not R-8)

[Regnar]

Jim it is a M-head with a MT2 tooling. Not hard to come by but not as easy as R8 or new collet systems.

[JamesJ]

Jim
The first thing that comes to mind is cost. Ball screws aren't cheap. I also think you will have pretty long timing belts which will have to be pretty tight due to their lenght. You will also lose the flexability that two motor drives gives you. Timing two ballscrews vs simple adjustments in Mach3. I'm thinking the mechmate design is solid as is, that is why I am sticking pretty close to plan when it comes to drive arrangements.

[JLFIN]

russell, seams to me mine(which i dont think i ran) had a 3 pc split collet thing that went together inside of the locking nut, but it's been alot of yrs. good luck with that build i am sure you will enjoy it.

[JLFIN]

Jim, I'll be honest, I don't know the mach control at all, but if that were the issue a guy could put a motor on both ends. the prices i've seen on some of these links tells me that ball screws aren't as pricey as they used to be and i don't think they need to be huge (.75 or .875) but I agree, can you syncronize the ball screws? The length of the timing belts would only be about 26 inches

[Gerald D]

Cheap ballscrews have cheap seals and they jam up after being exposed to lots of dust.

[oopz]

In addition to Geralds comment above. Would You Might Need a SPINNING - NUT due to the length of the screw in the X axis (even Y if you ask me). Due to there is a high risk of that the ballscrew begins to wobble. That - and reconstruct the design (or buy a spinning nut) takes both more time and costs significantly more $ $ $. Thats my opinion (and experience) in order to obtain the same reliability in design as MM has.

For what it's worth do other DIY hardware / designers pursue to use the R & P.
In there later creations, so it seams as its cost effective..And if anything happens, it is very easy to repair to a low cost. For me was MM's use of the R & P a strong advantage.

Hope it helped you..!

/oopz

[JamesJ]

Managed to get a little shop time in this weekend and was able to get the pinion gears cut down. Need to drill and tap for the set screws next. I plan to use two set screws 90 degrees apart. Anyone else used this approach?

[JamesJ]

Jim
BTW, the wire method worked great. I was able to indicate the gear blank down to 2 tenths before boring for the shaft. Thanks!

[DeadGuy]

Hi Jim,

One question, where did you get the gear blank?

Dennis