# designing a lathe



## jimmyjames

Hi I'm currently thinking about the design of a lathe. Im trying to figure out some forces involved. I want to be able to turn big stuff, I'm talking like 24" long x 16" diameter+, I was thinking about using 1.5" pillow blocks for the spindle. If I do bore out the spindle for a Morse taper a lot of strength in the shaft will be lost. Does anybody have any pictures of the shaft on they're "big" lathe and possibly a bearing size and also what Morse taper it has and also a thread size and pitch? It just seams that with a 1 1/4 thread it doesn't seem very heavy duty, especially if I strap a 75lb log to it.... I want this thing to be indestructible.... also I have thought about using a 3 phase motor and a speed controller. The speed controllers can be found on eBay for relatively cheap for 3hp or less 3 phase motors.


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## jimmyjames

I will do that, thanks for the info. I also want to be able to do small things as well and be very stable and accurate, I'm probably going to build it so the base can be filled with sand, I would think that 500lbs+ of sand should help stabilize it and also I'm guessing the frame alone will weigh upwards of 500lbs plus the weight of the motor, spindle, covers etc. Probably 1200lb operating weight.


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## Mike Jones

Jimmyjames....

Here is Powermatic's basic info for a 3hp woodturning lathe,

http://powermatic-online.com/powermatic-lathes-1/4224-lathe-3hp-will-operate-1ph-or-3ph-230v.html

I think you can get spindle dia. , bearings, and similar info by going to Powermatic Repalcement parts.

Most of the "guys" say..."you can turn tiny on a big lathe, but you can't big on a tiny lathe"

hmmmm, you must be lookin' at some BIG 'ol logs! :no dice.


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## barry richardson

Even the big rigs use mt-2 and 1 1/4 x 8. I would stay with the standard, much easier to get accessories that way. I think it is heavy enough.. For my money I would get the biggest beefiest bearings you can find. I use a 1642 and I have beat the crap out of it. The spindle has held up fine, but the bearings are starting to go. Another thing I would want extra beefy is the tail stock assembly, Mine is shot because I like to use big bore forstners to drill out centers, and it couldnt handle the torque.


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## Tim Carter

Take a look at the Nichols lathe post. It has a massive spindle, set in pillow blocks, with a 1 1/2" x 8 tpi and a no.2 morse taper. The body has 2 access ports to fill it with sand. As it sits, it has a 26" swing that can be increased to 40" by sliding the bed further out. It also has an auxillary bed that mounts at a right angle to the primary bed to allow you to turn the back side of a large bowl or hollow form. It also has a built-in crane to help you mount large blanks. Great lathe!


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## jimmyjames

One thing i need to figure out if its really worth the headache and cost involved in making the spindle with the morse taper, alot probably thing that a morse taper is just drilled and reamed and done, thats not the case, it needs to be a precise ground fit, probably lapped to make it fit correctly, the added cost would be substanial. The only other option is to find a shaft with the morse taper already in it and then machine the rest, but finding one will be almost impossible and will probably be hardened and have to be hard turned which is a big chore in itself..... Does anybody on a regular basis use morse taper tools in your spindle? And if so what do you use and why?


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## EricJS

jimmyjames said:


> One thing i need to figure out if its really worth the headache and cost involved in making the spindle with the morse taper, alot probably thing that a morse taper is just drilled and reamed and done, thats not the case, it needs to be a precise ground fit, probably lapped to make it fit correctly, the added cost would be substanial. The only other option is to find a shaft with the morse taper already in it and then machine the rest, but finding one will be almost impossible and will probably be hardened and have to be hard turned which is a big chore in itself..... Does anybody on a regular basis use morse taper tools in your spindle? And if so what do you use and why?



I mostly use a morse taper for some of my pen turning accessories. Nothing else. 

If you could find a shaft with a morse taper already in it, could it be accurately held in place with a quality chuck?


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## NYWoodturner

EricJS said:


> jimmyjames said:
> 
> 
> 
> One thing i need to figure out if its really worth the headache and cost involved in making the spindle with the morse taper, alot probably thing that a morse taper is just drilled and reamed and done, thats not the case, it needs to be a precise ground fit, probably lapped to make it fit correctly, the added cost would be substanial. The only other option is to find a shaft with the morse taper already in it and then machine the rest, but finding one will be almost impossible and will probably be hardened and have to be hard turned which is a big chore in itself..... Does anybody on a regular basis use morse taper tools in your spindle? And if so what do you use and why?
> 
> 
> 
> 
> I mostly use a morse taper for some of my pen turning accessories. Nothing else.
> 
> If you could find a shaft with a morse taper already in it, could it be accurately held in place with a quality chuck?
Click to expand...


Jimmy - I can speak to the use of the lathe and the morse taper - but understand that as far as machining, i don't know my arse from my elbow - so my suggestion may be completely ridiculous ...
A morse taper in the tail stock is priceless. I wouldn't even consider a lathe without it. 
In the headstock, I use it for a pen mandrel as Rob mentioned, a buffing wheel set up, A steb center almost daily, a collet chuck from time to time, bowl buffs, and when I had a jet lathe I used it for realignment purposes with a double ended M2 taper to align perfectly with the tail stock. It seems like I am missing a few, but I would say that having it has helped me out of more tight spots than not having it. The most critical of those would be the steb center and yes you could hold it in a good chuck, but I have have problems with that on large heavyweight pieces of wood. The chuck does not allow for a Steb center to extend much more than an inch beyond the jaws. The inability to get adequate bite from those teeth can lead to safety issues. Only one bad accident could offset the cost and aggravation. 
So here is my suggestion / question. Could you find an old junker that is inoperable for next to nothing and re-purpose the headstock MT out of it? Or is that just completely ridiculous? ~ Scott


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## woodtickgreg

Or just order a spindle from one of the manufacturers and build around it. :dunno: Possibly look at grizzly on line to look up parts for their lathes and check the cost of a spindle. It could be a real time saver?


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## jimmyjames

woodtickgreg said:


> Or just order a spindle from one of the manufacturers and build around it. :dunno: Possibly look at grizzly on line to look up parts for their lathes and check the cost of a spindle. It could be a real time saver?



That's exactly what I was thinking, I can turn the spindle but the cost of sending it out and having the taper ground to a +/-.0002" is very costly, anything less accurate the Morse taper would be useless as it wouldn't engage to the required 70% , and when your turning something and the Morse taper let's go really bad things could happen. I'm going to call around and try to find a replacement shaft.


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## Kevin

Keep us updated I am reading every post of this thread.


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## Dennis Ford

My lathe is not quite as big but it is home-made. The max swing is 22 inch diameter. I have turned pieces that started over 200 lbs. Spindle is threaded 1-1/4 x 8 tpi and has a morse 2 taper. The front bearing is a double row angular contact ball bearing 80mm OD x 40mm ID, the rear bearing is a single row ball bearing 30mm ID. The morse taper was drilled, bored and reamed. not ground; it works fine. The tail-stock taper was done the same way and also works fine. I am not a real machinist but did learn a lot while building this lathe. 
The attached picture is a couple of years old, I have made a couple of tweaks since but nothing structural.[attachment=21528]


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## NYWoodturner

Dennis - That's just as impressive as hell  ~ Scott


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## Kevin

Very nice Dennis. What type of variable speed controller are you using?


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## Mike Jones

jimmyjames said:


> One thing i need to figure out if its really worth the headache and cost involved in making the spindle with the morse taper, alot probably thing that a morse taper is just drilled and reamed and done, thats not the case, it needs to be a precise ground fit, probably lapped to make it fit correctly, the added cost would be substanial. The only other option is to find a shaft with the morse taper already in it and then machine the rest, but finding one will be almost impossible and will probably be hardened and have to be hard turned which is a big chore in itself..... Does anybody on a regular basis use morse taper tools in your spindle? And if so what do you use and why?



Not having a morse taper in the headstock spindle would frustrate me right into golf...or bridge....the casino maybe. A spur drive starts many of my projects, until I can get a tenon turned on the tailstock end...then reversed and held with a scroll chuck. I, too, have used it to spin buffs, mandrels, and a drill chuck. It's worth it.


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## jimmyjames

Kevin said:


> Very nice Dennis. What type of variable speed controller are you using?



Im curious to this as well, ive been eye balling the teco 7300cv and running it on a 3hp 3 phase motor.


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## jimmyjames

Well i think i found a spindle, bearings and all, im not sure if its beefy enough but by the specs of the machine its for it should be, from the biggest grizzly lathe they sell, $165 for the spindle? theres no way i could make it for that price, especially saving me a bazillion hours drawing, writing programs, expensive reamers etc.... they also sell the morse taper tailstock parts for cheap, tailstock quill for $13?? wowza....

the spindle bearings they list is part number LM67048/10, which is a 1.25" id x 2.328 od x .625 bearing, so that means the shaft is 1.25" diameter which sounds ok, i would rather have it 1.5" or even bigger but.... 

http://www.grizzly.com/products/G0694/parts/LATHE


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## woodtickgreg

jimmyjames said:


> Kevin said:
> 
> 
> 
> Very nice Dennis. What type of variable speed controller are you using?
> 
> 
> 
> 
> Im curious to this as well, ive been eye balling the teco 7300cv and running it on a 3hp 3 phase motor.
Click to expand...

The teco's are good units. I purchased one for my metal lathe. Haven't got it wired up yet as I have been working on a couple of other projects, but soon! All the wire is ran, just gotta hook it up and program it.


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## jimmyjames

woodtickgreg said:


> jimmyjames said:
> 
> 
> 
> 
> 
> Kevin said:
> 
> 
> 
> Very nice Dennis. What type of variable speed controller are you using?
> 
> 
> 
> 
> Im curious to this as well, ive been eye balling the teco 7300cv and running it on a 3hp 3 phase motor.
> 
> Click to expand...
> 
> The teco's are good units. I purchased one for my metal lathe. Haven't got it wired up yet as I have been working on a couple of other projects, but soon! All the wire is ran, just gotta hook it up and program it.
Click to expand...


Did you get the cable to hook it up to your computer and program it that way? Have you read up on the dynamic braking it has and did you get the resistor thingy for the braking?


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## jimmyjames

Looks like the most costly things will be the spindle assembly parts, tailstock assembly parts and motor and the vfd, I already have a motor but its single phase, will need to source a 3ph, other than that stuff I listed I have all of the iron to build it other than a couple pieces of ground flat stock for making the ways, probably have maybe $1000-$1200 in it total. One thing I still need to decide on is the pulley arrangement, a lot of them I notice they use serpentine belt step pulleys which are expensive but I could make but having a good vfd that will still give the motor low end torque is the step pulley arrangement needed? What's the max rpm you turner folk use on your lathe? If I just do a single pulley with a 1:1 ratio that would give me 1750 rpm max spindle speed, will I need anything higher than that? And I'm guessing that the minimum spindle speed needed will be maybe 200rpm? My only concern is that turning the motor at 200rpm with the vfd it won't have enough torque therefore needing a step pulley arrangement to turn the motor at a higher rpm to multiply the torque and also get the motor into its "power band". Any thoughts on this? The stepped serpentine pulleys are about $200 each but I can probably make them for $50 each and have about 4 hours into them....


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## jimmyjames

I'm thinking that a stepped pulley will be a must, I believe 1750 max rpm is far too low


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## woodtickgreg

jimmyjames said:


> woodtickgreg said:
> 
> 
> 
> 
> 
> 
> jimmyjames said:
> 
> 
> 
> 
> 
> Kevin said:
> 
> 
> 
> Very nice Dennis. What type of variable speed controller are you using?
> 
> 
> 
> 
> Im curious to this as well, ive been eye balling the teco 7300cv and running it on a 3hp 3 phase motor.
> 
> Click to expand...
> 
> The teco's are good units. I purchased one for my metal lathe. Haven't got it wired up yet as I have been working on a couple of other projects, but soon! All the wire is ran, just gotta hook it up and program it.
> 
> Click to expand...
> 
> 
> Did you get the cable to hook it up to your computer and program it that way? Have you read up on the dynamic braking it has and did you get the resistor thingy for the braking?
Click to expand...

The one I have programs with the touch pad, I did not get the resistor for braking but braking is adjustable through the key pad also. With my metal lathe you don't want it to stop too quickly or the chuck can spin off and that would be bad. But the one I have is also in a nema 4 wash down enclosure. If it's water proof it's also dust proof, dust is not good for these things. It is also capable of variable speed through the touch pad or you can mount a variable speed pot externally.


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## Dennis Ford

I am using a Hitachi VFD; it is not the least expensive (nor the most expensive). I have heard good things about the TECO units also.


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## jimmyjames

jimmyjames said:


> I'm thinking that a stepped pulley will be a must, I believe 1750 max rpm is far too low



or i could go with a 3450 rpm motor? Dang im having an entire conversation with myself :wacko1::wacko1:


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## barry richardson

If, as you say, you want to use it for big stuff, 1750 rpm is about twice as fast as you will ever need to go. 1750 is plenty fast enough for turning spindles too.


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## waterboy12

When I turn large stuff (>14") on my nova I'm usually in the 500-800rpm range. Fallowing the Diameter x RPM = 6,000-9,000 rule.


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## davidgiul

I am enjoying the thread, Jimmy. Thanks for starting it and continuing it.


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## jimmyjames

Well heres some progress on the lathe, decided on a 40" swing and 60" bed, the spindle height will be 36". I cannot go much further on the design until i get some parts for it so i can do some measuring. The tube for the bed is a piece of 8"x8"x1/2" wall square tube that i have, the bed is made from ground 4140 flat stock and a 3/4" piece of 2" wide cold roll for a spacer between the ground flat stock and tube. I plan on filling the 8" tube with sand and also the base of the headstock side of the lathe.

bottom of tailstock
http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock2_zps7d6ab12e.jpg

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock1_zps663230f0.jpg

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock3_zpsc5039153.jpg

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock4_zps257677de.jpg

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock5_zpsefffe896.jpg

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock6_zpsb9058f8d.jpg

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock7_zps46b596f2.png

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock8_zps8c5f39b3.png


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## jimmyjames

Added the foot on one side, need to draw the pieces to box it in, and also a bolt on plate for the end of the bed tube so i can add or remove sand easily.

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock9_zps3408481a.png


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## jimmyjames

added gussets around bolt holes for floor mounting
http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock91_zps84d623d1.jpg


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## Mike Jones

jimmyjames said:


> I'm thinking that a stepped pulley will be a must, I believe 1750 max rpm is far too low



And 200 RPM is too fast.....if you want to sand a spinning piece. Not only will that much speed blow sanding dust beyond the DC capacity to capture it, it will also create heat. Heat can be bad for the wood...and for the fingers.


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## Mike Jones

jimmyjames said:


> Added the foot on one side, need to draw the pieces to box it in, and also a bolt on plate for the end of the bed tube so i can add or remove sand easily.
> 
> http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock9_zps3408481a.png



...._." the spindle height will be 36".._....... Too low! Rule of thumb puts the spindle height at about "the crook of the elbow".

Also: The tube is 1/2" wall steel? I question whether you will gain much by filling this with sand. Your ballast, if you think that you will need it, would be better placed nearer the floor.

I'm checking "Priceline" for flights to Council Bluffs......I gotta see this when finished!  (Great thread!


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## jimmyjames

Mike Jones said:


> jimmyjames said:
> 
> 
> 
> Added the foot on one side, need to draw the pieces to box it in, and also a bolt on plate for the end of the bed tube so i can add or remove sand easily.
> 
> http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock9_zps3408481a.png
> 
> 
> 
> 
> ...._." the spindle height will be 36".._....... Too low! Rule of thumb puts the spindle height at about "the crook of the elbow".
> 
> Also: The tube is 1/2" wall steel? I question whether you will gain much by filling this with sand. Your ballast, if you think that you will need it, would be better placed nearer the floor.
> 
> I'm checking "Priceline" for flights to Council Bluffs......I gotta see this when finished!  (Great thread!
Click to expand...


You know i was thinking the same thing about the weight needing to be closer to the floor, but any added mass regardless of where its placed will make it more stable, On the height, i can easily change that with a few mouse clicks, i will have to measure how high the crook in my elbow is , thanks for the info Mike  Oh and the 8x8 tube weighs about 50lbs per foot, and is about 80" long, so about 325lbs worth of tube....


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## jimmyjames

Mike, looks like my "crook" is 48" from the floor, so should i make the spindle 48" from the floor? Im used to metal lathes and most tool room lathes are about 40" im guessing, but on those your not holding the cutting tools either.....


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## jimmyjames

ok, edited the associated parts for the leg and the spindle height is now 48"

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock92_zps313d41f3.jpg


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## Dennis Ford

48" spindle height sounds about right.

You might consider a little more space between the ways and the square tube; shavings tend to build up there, you need to be able to get them out.

Your graphic skills are impressive as is the design.



jimmyjames said:


> ok, edited the associated parts for the leg and the spindle height is now 48"
> 
> http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock92_zps313d41f3.jpg


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## jimmyjames

Dennis Ford said:


> 48" spindle height sounds about right.
> 
> You might consider a little more space between the ways and the square tube; shavings tend to build up there, you need to be able to get them out.
> 
> Your graphic skills are impressive as is the design.
> 
> 
> 
> jimmyjames said:
> 
> 
> 
> ok, edited the associated parts for the leg and the spindle height is now 48"
> 
> http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock92_zps313d41f3.jpg
Click to expand...


Thanks, im self taught on this particular software, on the spacing for the tube, the space from the bottom of the tailstock clamp plate and the tube is .320", i will have to clean it out before i go to move it but even if i had a 12" gap in it i will still have to clean it out. I appreciate the input though. On the ways they will bolt to the spacer with counter sunk allen head screws and the spacers will be welded to the tube, after i weld the spacers to the tube and get the ways bolted on im sending it out to be ground flat at a local grinding company, probably overkill but the company i work for sends them hundreds of thousands of dollars of work and i know the owner so he owes me a "favor" or 2...

Is there anything else i should consider or possibly change dennis? Again i appreciate the input.


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## woodtickgreg

Have you ever looked at a Robust American beauty lathe? They use a square tube like you are doing but they stand it on edge so the chips and dust just fall off. It would mean making and welding a bunch of uprights to mount the bed to but not that difficult really. It's just a thought and since you are still in the design stage it might be worth looking at. Just google Robust American beauty lathe for some pics. If money was no object it would be my lathe of choice.


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## jimmyjames

woodtickgreg said:


> Have you ever looked at a Robust American beauty lathe? They use a square tube like you are doing but they stand it on edge so the chips and dust just fall off. It would mean making and welding a bunch of uprights to mount the bed to but not that difficult really. It's just a thought and since you are still in the design stage it might be worth looking at. Just google Robust American beauty lathe for some pics. If money was no object it would be my lathe of choice.



Those look like nice machines, only thing i dont like about them is the motor placement wouldnt allow outboard turning. The design on the bed is pretty clever but would increase the cost considerably, the most expensive thing in my build will be the laser cutting of the flat plate parts, with going with that design it would more than double my laser cutting costs and also the amount of 1/4" plate i would need to purchase, im basically designing this around the supplies i have on hand. Plus im the type of guy that engineers something as simple as possible  I see some of the lathes they sell have the headstock mounted on the ways and to do outboard turning you slide the headstock to the other end of the lathe, thats really overcomplicating a design, and im sure theyre price shows it.


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## DKMD

This is a cool thread, Jimmy! One thing I haven't seen mentioned is having some kind of through hole in the spindle. If you're going to use morse taper accessories, you'll need some way to bang them out. It's also a necessity for vacuum chucking. There's a lot that can be done without a vacuum chuck, but now that I have one, I wouldn't want to do without it.

I looked at the grizzly spindle you referenced, and I couldn't tell whether it had a through hole or not... I'd definitely make sure it has one.

The other thing that came to mind was incorporating some kind of 'swing away' for the tailstock. On a lathe this size, you're invariably going to use a steady rest for large items, and lugging the tailstock on/off is a royal pain the the rear. Some hollowing rigs require removal of the tailstock as well. I've got a Butler swing away on my Powermatic, and I like it. The Robust and others use a hinged/fold down mechanism if I remember correctly.

One other thought... 40" of swing is a lot, and probably more than I would ever want inboard. The reach from banjo to working height would require a very beefy tool post and a long, beefy banjo assembly to deal with the increased swing. Depending on how you design it, you may not be able to use stock toolrest and accessories that mount in a traditional banjo due to the length and size of the tool post that you may need.

Just remember the further you get away from industry standards, the more custom tooling will be required to accessorize your machine. Best of luck and keep the posts coming... I'm geting a kick out of this thread.


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## jimmyjames

DKMD said:


> This is a cool thread, Jimmy! One thing I haven't seen mentioned is having some kind of through hole in the spindle. If you're going to use morse taper accessories, you'll need some way to bang them out. It's also a necessity for vacuum chucking. There's a lot that can be done without a vacuum chuck, but now that I have one, I wouldn't want to do without it.
> 
> I looked at the grizzly spindle you referenced, and I couldn't tell whether it had a through hole or not... I'd definitely make sure it has one.
> 
> The other thing that came to mind was incorporating some kind of 'swing away' for the tailstock. On a lathe this size, you're invariably going to use a steady rest for large items, and lugging the tailstock on/off is a royal pain the the rear. Some hollowing rigs require removal of the tailstock as well. I've got a Butler swing away on my Powermatic, and I like it. The Robust and others use a hinged/fold down mechanism if I remember correctly.
> 
> One other thought... 40" of swing is a lot, and probably more than I would ever want inboard. The reach from banjo to working height would require a very beefy tool post and a long, beefy banjo assembly to deal with the increased swing. Depending on how you design it, you may not be able to use stock toolrest and accessories that mount in a traditional banjo due to the length and size of the tool post that you may need.
> 
> Just remember the further you get away from industry standards, the more custom tooling will be required to accessorize your machine. Best of luck and keep the posts coming... I'm geting a kick out of this thread.



yes the grizzly spindle has a through hole, if it didnt there wouldnt be any way to knock out the morse taper tools. The tool post will be beefy, im actually designing it as we speak, it will be stout.


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## Dennis Ford

jimmyjames said:


> Dennis Ford said:
> 
> 
> 
> 48" spindle height sounds about right.
> 
> You might consider a little more space between the ways and the square tube; shavings tend to build up there, you need to be able to get them out.
> 
> Your graphic skills are impressive as is the design.
> 
> 
> 
> jimmyjames said:
> 
> 
> 
> ok, edited the associated parts for the leg and the spindle height is now 48"
> 
> http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock92_zps313d41f3.jpg
> 
> 
> 
> 
> 
> Click to expand...
> 
> 
> Thanks, im self taught on this particular software, on the spacing for the tube, the space from the bottom of the tailstock clamp plate and the tube is .320", i will have to clean it out before i go to move it but even if i had a 12" gap in it i will still have to clean it out. I appreciate the input though. On the ways they will bolt to the spacer with counter sunk allen head screws and the spacers will be welded to the tube, after i weld the spacers to the tube and get the ways bolted on im sending it out to be ground flat at a local grinding company, probably overkill but the company i work for sends them hundreds of thousands of dollars of work and i know the owner so he owes me a "favor" or 2...
> 
> Is there anything else i should consider or possibly change dennis? Again i appreciate the input.
Click to expand...

Having the spacers ground flat is a very good idea; not overkill IMO. Using 4140 steel for the ways may be overkill (IMO).

With 40" swing, you will need lots of torque and some slow speeds for the rare occasions that you turn something that big. I recommend a large (3 hp) 3ph motor, a VFD *and* step pulleys. Three ranges on the step pulleys should be adequate (perhaps 600, 1200, 1800 rpm at rated motor speed). On a 1750 rpm motor, you can go above 60 hz and get 2000 - 2400 rpm with no problem. You will probably not use speeds that high anyway.


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## jimmyjames

Thanks for the info dennis.

Heres the toolpost, its made with 3" od. DOM steel tube, havent decided on the id. yet, i see most toolpost accessories are at 1" but some go up to 1 1/2" but are hit and miss. The bottom of it is made with 2 bars of 2" x 1.25" with a 1/2" gap between the two making the total dimension 3" wide x 2" thick. Also the final height of the toolpost will be determined once i figure out which ones i will use.

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock93_zpsb36c38f8.jpg


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## jimmyjames

Also i figured up the final weight and it will be between 1475 and 1600lbs with the 8" tube filled with sand


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## jimmyjames

Also boxed in the leg which will also be full of sand

http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock94_zps80b23d42.jpg


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## DKMD

Looks cool, Jimmy! Any consideration to adding some kind of angle bracket or support between the upright and horizontal portions of the banjo? My worry with the swing being so large is that there might be significant vibration with such a long reach from bed to rest... Of course, I may be overanalizing...


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## jimmyjames

DKMD said:


> Looks cool, Jimmy! Any consideration to adding some kind of angle bracket or support between the upright and horizontal portions of the banjo? My worry with the swing being so large is that there might be significant vibration with such a long reach from bed to rest... Of course, I may be overanalizing...




That's a good idea, I will add some gussetts to the inside corner. On another note I see some guys with big bowl lathes use a tool post that's on a totally desperate stand that sits on the floor, I'm not sure how well that would work.... it would be a bad day if it walked on the floor into a giant spinning log..... I've watched a lot of questionable videos on peoples lathe practices, big logs not held in with the tailstock and are way out of balance and spining them way faster than I would ever be comfortable doing..... another video I watched a guy was turning a bowl out of a square block and was cutting it round from the face and when he got to the end I knew a big chunk was going to fly off.... sure enough it exploded and wiped out his hand... bleeding everywhere...... I don't know why somebody wouldn't trim a block down from square and at least make it into a stop sign shape first.


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## jimmyjames

Dennis Ford said:


> jimmyjames said:
> 
> 
> 
> 
> 
> Dennis Ford said:
> 
> 
> 
> 48" spindle height sounds about right.
> 
> You might consider a little more space between the ways and the square tube; shavings tend to build up there, you need to be able to get them out.
> 
> Your graphic skills are impressive as is the design.
> 
> 
> 
> jimmyjames said:
> 
> 
> 
> ok, edited the associated parts for the leg and the spindle height is now 48"
> 
> http://i178.Rule #2/albums/w249/jimmyjames1981/tailstock92_zps313d41f3.jpg
> 
> 
> 
> 
> 
> Click to expand...
> 
> 
> Thanks, im self taught on this particular software, on the spacing for the tube, the space from the bottom of the tailstock clamp plate and the tube is .320", i will have to clean it out before i go to move it but even if i had a 12" gap in it i will still have to clean it out. I appreciate the input though. On the ways they will bolt to the spacer with counter sunk allen head screws and the spacers will be welded to the tube, after i weld the spacers to the tube and get the ways bolted on im sending it out to be ground flat at a local grinding company, probably overkill but the company i work for sends them hundreds of thousands of dollars of work and i know the owner so he owes me a "favor" or 2...
> 
> Is there anything else i should consider or possibly change dennis? Again i appreciate the input.
> 
> Click to expand...
> 
> Having the spacers ground flat is a very good idea; not overkill IMO. Using 4140 steel for the ways may be overkill (IMO).
> 
> With 40" swing, you will need lots of torque and some slow speeds for the rare occasions that you turn something that big. I recommend a large (3 hp) 3ph motor, a VFD *and* step pulleys. Three ranges on the step pulleys should be adequate (perhaps 600, 1200, 1800 rpm at rated motor speed). On a 1750 rpm motor, you can go above 60 hz and get 2000 - 2400 rpm with no problem. You will probably not use speeds that high anyway.
Click to expand...


I was thinking the 4140 may be overkill as well, its the cheapest ground flat stock you can get before you get into the d2, s2 tool steels etc, but if I'm going to grind it anyway I could just do it out of 1018 and case harden it a bit for durability with a torch. But then again I may be way over thinking it, I'm just used to metal machining machines that need to be as accurate as possible


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## jimmyjames

Hey guys I came across a good deal on a 5hp 3phase motor, I know the vfd will cost a little bit more for a 5hp vs a 3hp but the price for a descent new 3hp is about $400, this one is new, inverter duty for $200 and my brother can pick it up for me and bring it with him when he comes and visits. This motor is a face mount which I can work with, is it overkill?? 

http://omaha.craigslist.org/bfs/3628959239.html


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## jimmyjames

The Linky doesn't work now because I just bought it, its a marathon inverter duty motor with the higher voltage insulation so its rated to be ran with a vfd its a 208-230/460 volt 3 phase, weighs 95lbs and has a 1 1/8" shaft, a 3hp inverter duty baldor is $569 locally, so I think its a good deal, the cost difference for the vfd is $70 so I'm still saving money in the long run


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## barry richardson

Probably more power than you will ever need, but who knows, if your roughing out some 40" diameter logs you may need it. I know I stall out my 2hp all the time and wish I had 3.


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## jimmyjames

Dang rob I don't think k I could finish the salad that came in a bowl that big....


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## Mike Jones

Joe Rebuild said:


> I think your are thinking too small...
> 
> I could turn for months with a single piece of that crib structure!


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## jimmyjames

No kidding, just the cost of the cribbing under that tractor is probably more than the tractor is worth.... when I was a crane operator our company bought crane Matt's made from 4 timbers 12"x12"x20' bolted together, each one of those mats were $1200... there's probably $15,000 in cribbing right there..... I think our mats were bur oak


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## woodtickgreg

I think the bigger motor would be a good thing, especially at the slower speeds = better torque. Price would work for me too. And you are right, a bigger inverter will cost more but be worth it, IMO.


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## DKMD

I don't think you can have too much power although it's certainly not a necessity. I can stall my 2hp quite easily while coring... Of course, 5hp might put me through the ceiling into the attic with a good catch.


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## Dennis Ford

5 hp is a lot of motor for a beginning turner but not too much for an experienced turner when doing good sized stuff. It will allow you to turn the speed down and still have a lot of power without changing the belt position very often.
Just be aware the the power and inertia of this motor will not have much forgiveness if you get a catch (set the belt tension so that it can slip if you get in a bind)

You will enjoy the extra power and you got a good deal!


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## jimmyjames

I'm used to lathes having 20hp plus direct driven, but that's alot different than holding the tool in your hand, I will start off with small stuff, it will be a long time before I ever think k about doing anything big, I need to get the feel for it and proper tool selection down before I do anything.


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## elnino

5hp, 40inch swing! wow. 40 seem huge for over the ways. what are you going to turn that huge?


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## jimmyjames

elnino said:


> 5hp, 40inch swing! wow. 40 seem huge for over the ways. what are you going to turn that huge?



Probably nothing that big but im not the type that likes to be limited


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## Mike1950

When You get done Jim- we need a picture of you turning a pen on it.


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## jimmyjames

Mike1950 said:


> When You get done Jim- we need a picture of you turning a pen on it.



OK


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## Tim Carter

If you're going that large on everything-I'd suggest you revisit the headstock spindle. Based on the earlier posts, it sounds like you're planning to use a 1 1/4" x 8 tpi spindle. The lathe's capacity is going to be 40" x 60", which means you could put a HUGE blank on this lathe. I have a Nichols lathe with a 40" swing and it has a 1 1/2" x 8 tpi spindle with a No. 2 Morse Taper. You might want to consider using the larger size.


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## jimmyjames

Well I messed around with my buddies lathe on Saturday, I've decided Morse taper number 2 is far too small, I couldn't trust a 300lb chunk of wood spinning on that little thing.... now that I think about it I'm not sure if I will use a taper on the spindle at all, the smallest I think I would go is number 3 if I do use a taper


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## jimmyjames

Look what just fell into my lap...... spindle from an old atlas lathe, 1 1/2"-8 tpi thread with morse taper #3, i will have to do a little bit of machining on it for a keyway for the pulley but it will work!! Im going to check too see if the tailstock shaft is laying around as well, it should have the same morse taper number 3 :)


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## woodtickgreg

Now your cookin, that tapered bearing will always allow adjustment too. What is the spindle thread? Only reason I ask is wondering if you can get standard chucks and stuff to thread on or if you would have to make your own adapters.:dunno:


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## jimmyjames

Its 1 1/2"-8tpi, I found one chuck but I believe its only a 4", I'd like something a little bigger, I can make just about everything else but the chuck


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## jimmyjames

Also that bearing was on it when I got it, I may switch to a different bearing, the shaft is made for 2 different size bearings


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## woodtickgreg

jimmyjames said:


> Its 1 1/2"-8tpi, I found one chuck but I believe its only a 4", I'd like something a little bigger, I can make just about everything else but the chuck


That is a standard size for the larger chucks for wood turners. vicmarc, oneway, etc.


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