My Second Rotary Table,80 mm table.

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Will finish up with the 71 tooth worm gear. Got my plus and minus wrong and ended up a mile off-course with the holes for the crank axle. :wall::hDe: Promise,will look for a 72 tooth spur gear to use as direct divider plate to help gash worm gear blank so as to get the 72 tooth .
Bearing housings done. Will use some bush engineering techniques to align crank axle. The cheapy carpentry clamps are quite easy to use. Its Neap Tide tomorrow and a bit windy,so no fishing and will spend time working on the RT. Hopefully I can crank/spin table .See foto.

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Will finish up with the 71 tooth worm gear. Got my plus and minus wrong and ended up a mile off-course with the holes for the crank axle. :wall::hDe: Promise,will look for a 72 tooth spur gear to use as direct divider plate to help gash worm gear blank so as to get the 72 tooth .
Bearing housings done. Will use some bush engineering techniques to align crank axle. The cheapy carpentry clamps are quite easy to use. Its Neap Tide tomorrow and a bit windy,so no fishing and will spend time working on the RT. Hopefully I can crank/spin table .See foto.

Hi Gus,
Put the shaft in eccentrics that will allow you to move the worm in and out of mesh. :):)
 
Hi Gus,
Put the shaft in eccentrics that will allow you to move the worm in and out of mesh. :):)

Good advice but I cheated with slightly larger holes on the bearing caps for room to adjust best rotating contact/fit.

Will most like build a vertical RT for gear cutting with indexing plates. Next RT will be further improvement.
 
Took total 4 hours to assemble worm drive and fit . After some adjustment and fitting, table can be crank. By early next week can complete RT but some reworks is expected. Will find a way to graduate table with 10 degrees spacing. Stamping the 0----360 degrees will be fun but no hurry.

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Looks nice. Is the rotation graduated in turns of the crank to degrees rotation?


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Hi Gus,
Looking good ! I like the knob and handle, it looks right.

Vertex sell a set of dividing plates intended for 90:1 ratio and 4 degrees per turn. Could save an awful lot of work.

I came into a fist full of goodies today. I'll take a picture later and post it.
 
Looks nice. Is the rotation graduated in turns of the crank to degrees rotation?


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Plan to graduate handwheel . Plan to granduate handwheel by 1 degree division and possibly 1/2 degree too basis I can successfully hob 72 T instead of 71 T. Now looking for or making a 72 index plate.
 
Had a great day. Made two table clamps out of scrap bin. The clamps have two clamping holes to prevent same colliding with table and jam. This happened with the last RT.Alignment circles on table cut. One of four tee slots cut.
Was finger biting when you are stretching a small mill to cut tee slots. When cutting tee slots,please ensure table is secured to prevent table movment.
6:40 pm now and getting dark.Gus cannot see too well at night.See no point in rushing and end up with a bad miss-cut tee slot.
The other three tee slots will be cut tomorrow. Hopefully I have enough time to try getting the elusive 72 tooth worm gear.

IMG_0247.jpg
 
Last edited:
Had a great day. Made two table clamps out of scrap bin. The clamps have two clamping holes to prevent same colliding with table and jam. This happened with the last RT.Alignment circles on table cut. One of four tee slots cut.
Was finger biting when you are stretching a small mill to cut tee slots. When cutting tee slots,please ensure table is secured to prevent table movment.
6:40 pm now and getting dark.Gus cannot see too well at night.See no point in rushing and end up with a bad miss-cut tee slot.
The other three tee slots will be cut tomorrow. Hopefully I have enough time to try getting the elusive 72 tooth worm gear.

Hi Gus,
By Gum, that is a mean looking T slot cutter.
I've been doing some more work on the QCTP and making mistakes. :wall::wall::wall:
 
I like that design. I will copy it.


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I like that design. I will copy it.


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Hi Rick,

You're very welcome.
The disk is 15 mm thick stainless steel. it was an offcut from a length of 75 mm diameter bar that I was given. Warning it is very tough stuff to machine. If I was doing it again I would use BMS or black bar. The cutting bit is 6 x 6 mm tool steel held in place by a 1/4", 1/4" whit grub screw. I made the shaft from 16 mm silver steel and turned a spigot on the end to press fit it into the hole. It sits square up to a shoulder.

I've tested it with a 0.5 mm DOC at 800 rpm on black bar. It went through it like butter leaving a very good finish. I ground the cutter with a radiused end and put 7.5 degree relief's on both front and top faces.

If I get chance I will do a drawing and post it.
Let me know how you get on when you make yours.
 
A note on the drawing, I just got Auto CAD on my computer. Time to exercise that part of the brain again.


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Got up early and after three hours of careful,cautious hard work ,tee slotted the Rotary Table. Its true the tee slot mill is a wee bitty big. The table clamps held table firmly while tee slots were milled.:)
Cast Iron is easy to mill but sure hate the CI dust which follows me to the shower bath and leave behind rust stains if you are not alert enough to thoroughly flush remnant dusts.
The 10mm slot was easy meat to mill and it is not required to hit dead bottom which the tee slot mill will mill off.
Tee Slot Cutter.
Be advised .Please ensure cutter is very firmly secured to mill chuck. Lesson learned today the chuck nut dropped out but cutter still firmly held.
At long last 4'' R.T. is 99% done,leaving behind the teeny weeny details to mop up. RT is quite forgiving.I did goofed wee bit but same goofs well hidden. The crank axle has ball bearings and thrust bearings and all NTN ,Japan bought from TpkyuHands.
The 'Tee Slot Nuts' will be done soon as I get back from Feb 22----March 2 Burma Bank Fishing Trip. I have a Power Reel Deep Sea Rod Holder to retrofit to bring up the 50----70 kg Tunas and Sharks.

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Hey Gus

I somehow missed following this thread, have just read from beginning, fantastic build, you have more patience than me, I have to admit I would have bought one, great job my hat is off to you.

Dave
 
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