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mtraven
04-05-2012, 05:09 AM
I am in the process of rebuilding my mower deck for my ford 1320. She needs a new set of wheels and I wanted them to be the last set she sees. Seeing how oem wheels run $100 a piece & are likely to break down again...and I have a lathe so why not make them? I found a deal on some 6" CR stock: 2peices of 5" length for $100, I pick it up on friday. I intend to make 4 wheels of 2" width and 6" less what I take off to true it. My lathe has a 16" swing, but I don't think my chuck is large enough to handle it. It will be close, but even if it is, the jaws will be real close to disengaged & I don't think that's an appropriate way to hold it.


Had a few different ideas to mount it properly, but wanted to see how some of you might do it? The more detail the better! thanks!

time is of the essence seeing how the lawn is growing & cutting 4 acres with a hand mower ain't fun at all.


ps...I have a couple old brake rotors that seem prized for a faceplate if that sounds like a good direction.

mike4
04-05-2012, 05:34 AM
Do you have a drillpress , if so as you are making wheels then just drill a 1/2 or 3/4 hole through the centre and put a grade 8 bolt through the hole with about 4'' of thread extended .
Put a couple of nuts on the thread after tightening the bolt .
Drill a centre hole in the head of the bolt deep enough for a live centre to help support the weight and start turning your wheels .

I have done this with pieces of 6' steel around 5 or so inches long when making bearing housings and just had to restrict the depth of cut to where the part did not stop turning while cutting.

Michael

scotplant
04-05-2012, 06:00 AM
My lathe has a 16" swing, but I don't think my chuck is large enough to handle it. It will be close, but even if it is, the jaws will be real close to disengaged

could you not remove chuck jaws and turn them round and hold it with the stepped side??
Tom..

J Tiers
04-05-2012, 07:59 AM
Mine is a 10" machine, and I would have no problems holding the part.

One way, with a chuck, is to use the outside jaw setting on a 6" or larger 4 jaw. That would require two setups per wheel.

Another is as above to drill and use some sort of mandrel, like the bolt.

Another is to mount on the faceplate, preferably on some sort of spacer.... hold-downs through the lightening holes (if any) or purpose drilled holes for hold-downs. That lets you bore the center hole AND turn the full outside in one setup.... not required for mere mower wheels, but useful for pulleys and other things where the two must be concentric.

gwilson
04-05-2012, 08:09 AM
I turned some 6" brass rings on my 10" Jet lathe back about 1975. They were hub bands for an 18th.C. style carriage. I could chuck them,but had to make a special tool to reach out and around those ring castings. I couldn't back the criss slide enough to get at the outside surfaces of the hub bands.

Fortunately,the castings were just real soft yellow brass,and I got the job done. The wheel hubs are still on the coach to this day.

I'm wondering if you also have a 10" lathe,Tiers,who could you get at the O.D. to do any turning on real metal,like steel?

As for the 16" lathe,old timers would have worked out a way to just securely bolt the wheels to the face plate. Early on,few ever even had chucks.

J Tiers
04-05-2012, 08:32 AM
A very simple trick for turning a max diameter part is to use a boring bar.

naturally for 6" dia in a 10" machine, there is no need to resort to any such measures, as there is at least 2" radius left outside the part. Not for LONG parts, but shorter stuff you can reach with carriage located so the part is not over the crosslide. Pulleys, wheels, etc. No propeller shafts....

But I have worked on 10" diameter pulleys on the 10" lathe. Put them on faceplate, and used boring bar or other semi-tricky setups to reach the work area. The 10" nominal Logan actually turns a part just shy of 11".

I forget what I did to work on the pulley V-groove, I think for that I must have retracted the compound and crosslide almost to max, because I do recall what tool I used.

Lew Hartswick
04-05-2012, 08:43 AM
If youre cutting 4 Acres with 6" diameter wheels you need a bigger
mower.
...Lew...

Carld
04-05-2012, 09:20 AM
I have a 13" lathe and turn 8" work as long as it's not to long.

If your going to make wheels out of 6" stock are you going to band saw them to 2" disc's? If so just chuck one up as straight as possible and face one side, flip it face the other side and bore the hole for the bushing or bearings.

I don't see a real problem doing the disc's. It's a mower and the OD concentricity is not that important.

garagemark
04-05-2012, 09:25 AM
Here's a dumb question: Why true up the 6" CR in the first place? These are not high speed wheels. Why not just cut your 2" slices, center drill them and bolt em on? Unless you need to cut bearing pockets or something else, I can't see the need for perfect deck wheels. 2" Slabs will last forever, or until the center hole wears out. Then simply sleeve them again and again.

I may have missed something though.

Mark

lakeside53
04-05-2012, 12:12 PM
I interpreted the OP question as a holding for a facing/boring operation.

Surely the 16 inch lathe can handle the stock if the jaws are turned around. My 14 with and 8 inch chuck can do it in a heartbeat. I've used expanding mandrels where the faces and OD of 7 inch stock needed to be done in one setup.

Dieseldoctor
04-05-2012, 01:10 PM
I think what the OP is wanting, since these seem to be anti-scalp wheels for a mower deck, is to crown the outside diameter so they don't tear up the grass while turning with wheels carrying some load. I would use a mandrel the size of the mounting bolt as previously suggested or drill a couple holes though web of wheels to bolt to faceplate also previously suggested.

mtraven
04-05-2012, 04:15 PM
wow 10 responses already, thank you all so much, let me try to respond to these suggestions:


If youre cutting 4 Acres with 6" diameter wheels you need a bigger
mower.
...Lew...

what do you mean by this? this are the mower wheels, its a belly mounted 60" wide deck....short of a brush hog or similar 3 pt implement I can't go any bigger.


could you not remove chuck jaws and turn them round and hold it with the stepped side??
Tom..

Could you clarify what you mean by the "stepped side"? when I pull the chuck, I have a 4 hole backer plate (with reg boss)....I do not own a faceplate at this time, but wouldn't mind an excuse to make one.


Before I realized my chuck wont handle it, I had planed on making nice hardy arbor out of some 1-1.5 cr I have...make a nice threaded shoulder at the end and maybe a second for the tail end. I have used this method many times to do my "normal" work(~1-2" stock) The trouble I have is putting the center hole it without the lathe. Yes I have a drill press, put have never had much luck in accurately locating the center & if I miss then I am starting with an irregular cut at 6" and I worry about the machine handling that . My drill press probably needs a good tramming if I am to go in that direction.



I have a 13" lathe and turn 8" work as long as it's not to long.

If your going to make wheels out of 6" stock are you going to band saw them to 2" disc's? If so just chuck one up as straight as possible and face one side, flip it face the other side and bore the hole for the bushing or bearings.

I don't see a real problem doing the disc's. It's a mower and the OD concentricity is not that important.

yes I plan on a band saw to slice them, but was thinking I would take the od down to true before than slice, but I still cant hold it for that first turning. My plan was similar to bore out bearing cups for ball bearings. and I know concentricity is not crucial, but I would like to do it well to expand my skill set.


Here's a dumb question: Why true up the 6" CR in the first place? These are not high speed wheels. Why not just cut your 2" slices, center drill them and bolt em on? Unless you need to cut bearing pockets or something else, I can't see the need for perfect deck wheels. 2" Slabs will last forever, or until the center hole wears out. Then simply sleeve them again and again.

Mark

my father suggested this....I am putting bearings it the wheels (2per wheel) & making new axle bolts to mount them. This is overkill, but the old steel on steel bearing arrangement led to the shafts looking like irregular cams and the bores to be nearly 0.250 over sized....it took about 20 years, for this wear to occur but I don't want to do it again, ever.


I interpreted the OP question as a holding for a facing/boring operation.

Surely the 16 inch lathe can handle the stock if the jaws are turned around. My 14 with and 8 inch chuck can do it in a heartbeat. I've used expanding mandrels where the faces and OD of 7 inch stock needed to be done in one setup.

I thought so to, unfortunate its a 16" swing with a 5" chuck...would love to get a big 4 jaw in the future, just not in the budget right now. I cant reverse the jaws, but I have 2 sets, neither are big enough.


I think what the OP is wanting, since these seem to be anti-scalp wheels for a mower deck, is to crown the outside diameter so they don't tear up the grass while turning with wheels carrying some load. I would use a mandrel the size of the mounting bolt as previously suggested or drill a couple holes though web of wheels to bolt to faceplate also previously suggested.

this is correct, although I am planning to create a lip on either side to retain some rubber treads I'm making to give a little cushion to the wheels & keep the power coating on the entire chuck of steel....rust always worries me on agriculture equipment.

Given the suggestions, I am inclined to go with the mandrel method as I intended, but starting that hole on the drill press...something I never do, because I have a lathe, could you all give me some advice on getting that center hole accurate? I know I can turn it true no matter where the hole is, but I'de like to keep as much material as possible. thanks again everyone!

RussZHC
04-05-2012, 08:58 PM
Its not the most accurate but for smaller round stock I use a center square (3" and under) but for the size you have, try using the center head of a combination square set

http://www.mcmaster.com/#combination-squares/=gzaj3o

Astronowanabe
04-06-2012, 02:46 AM
you can also use a live centre to press/clamp the disks against the jaws of your chuck to true them up, as long as you are not taking big cuts it works fine

the more you expand the jaws out, the more leverage less slippage you will see

914Wilhelm
04-06-2012, 03:16 AM
Lot of work for going and getting something off the shelf like this:

http://www.harborfreight.com/7-inch-semi-solid-wheel-98951.html

Jaakko Fagerlund
04-06-2012, 03:37 AM
you can also use a live centre to press/clamp the disks against the jaws of your chuck to true them up, as long as you are not taking big cuts it works fine

the more you expand the jaws out, the more leverage less slippage you will see
Was going to suggest this same thing, you only need a center drill hole in the stock.

Getting the punch mark for drill press in the center of stock is easy: Just measure the OD, halve it, lock your calipers to that number and scribe a line from couple of directions to get about a square in the middle of the stock. Then just punch mark the center of that tiny little square and it is good enough :)

fixerdave
04-06-2012, 03:55 AM
If you're going to make bearing cups... you can't use a central mandrel :confused: I mean, that would work to true up the outside, but then what? You still can't chuck it. Seems the best way is that multi-bolt clearance hole idea.

Spin up something that you can chuck and face yet allow a bolt radius bigger than your hub needs to be, maybe some clearance in the center for your boring. Drill and tap the bolt holes in it. Drill holes in your blanks larger than the bolts you intend to use so you can true it up on the above face-plate/mandrel thing if you're off in your drilling. Dial it in, tighten up the bolts. If you do well, you may not need to take anything off to true the outside.

I'm far from an expert but that's what I'd do. Well, I'd just park a big whack of old wrecked cars on all that grass and be done with it... but that probably wouldn't work for you.

David...

Jaakko Fagerlund
04-06-2012, 05:05 AM
Actually yiou can use a central mandrel, if the stock lenght allows. I recently had to do aluminum timing belt pulleys, they only had a 10 mm through hole in the center and a small hub on one side. I chucked them first from the hub, drilled through, bored the center hole to about the required diameter and then bored the bearing recess.

Once I had done this for all the pulleys, I chucked up some steel bar, turned a step that would fit snugly to the bearing recess in the pulley and also a small length that would fit the through bore. Then, drilled this deep, made a screw hole in the bottom of the hole and bored a 10 degree included angle in the front. On another lathe (or prior to turning this mandrel), I took a 12.9 SHCS that I turned to have that same angle in the head.

Last thing to do was to slit the end of the mandrel in 4 places with a cutoff disc mounted in an angle grinder, cleaning the cuts and presto! Instant expanding mandrel! This way I could put the halfmade pulley on the mandrel, tighten the screw and bore the other bearing recess without dialing in anything and without marring any surfaces :)

Timleech
04-06-2012, 05:25 AM
I've machined a couple of 23" flywheels, for starter ring gears, in my 19" lathe.

http://i559.photobucket.com/albums/ss38/Timleech_2009/DSCF2889.jpg

Method was to make a mandrel to fit the spindle internal taper, with a register to fit the flywheel bore. Then fit the flywheel to the mandrel with a drawbar through the headstock, and pressure from a revolving centre as a safety measure.

http://i559.photobucket.com/albums/ss38/Timleech_2009/DSCF2827.jpg

No help if it's the bore you need to machine, but worked well for the outer edge.
I tried a boring bar to begin with but the amount of metal that had to be removed would have taken ages, so welded a brazed tip turning tool to some heavy flat bar, which enabled me to take some decent cuts.

The flywheel needed to be tight against the headstock to allow it to fit in the cutouts at the end of the bed. It's not a gap bed, but the bed isn't quite full height for the first few inches, presumable to allow room for chuck jaws etc.


Tim

The Artful Bodger
04-06-2012, 05:42 AM
So, the need is to turn bearing cups concentric with the outer? And this is an exercise in turning as well as a practical job?

My suggestion, drill three holes at some convenient pitch circle and mount the blank to a face plate, put some scrap blocks in behind so that you can turn the diameter without fouling the face plate. True up the face of the work piece, drill the centre and bore one bearing cup. Flip the workpiece on the face plate and use a DTI on the diameter to centre it, bore the second bearing cup.

John Stevenson
04-06-2012, 05:47 AM
Probably too late now but if it had been me I'd have welded some wheels up from a boss, a plate and a section of thick walled tube.

Quick cheap and good enough for a mower.

Carld
04-06-2012, 09:26 AM
mtraven, do you have a three jaw or four jaw? If three jaw there should be two sets of jaws, one set with steps on the outside of center and one set with steps on the inside. One set will hold the ID of a tube and the other set will hold the OD of a tube. The jaws in a four jaw are reversible. That is, they can be removed and turned around so the steps are on the outside or the inside.

A 5" diameter chuck should be able to hold a 6" ID easily.

tmc_31
04-06-2012, 11:28 AM
I think I would go ahead and build or acquire a faceplate. Then mount the cylinder between centers with a drive dog (or two) through the faceplate and into the rear face of the work. In this case, the drive dog is simply a bolt that extends through the faceplate and into an appropriately sized hole about 3/8" deep bored into the rear face of the stock.

I did this when I had to reduce the diameter a 6" aluminum cylinder by about .250".

Tim

mtraven
04-06-2012, 02:13 PM
Lot of work for going and getting something off the shelf like this:
http://www.harborfreight.com/7-inch-semi-solid-wheel-98951.html
those particular wheels are too large, but I have searched all over & tried a few wheels like these, none have been satisfactory.


you can also use a live centre to press/clamp the disks against the jaws of your chuck to true them up, as long as you are not taking big cuts it works fine

the more you expand the jaws out, the more leverage less slippage you will see
I like this idea, I think I may try it...


If you're going to make bearing cups... you can't use a central mandrel :confused: I mean, that would work to true up the outside, but then what? You still can't chuck it. Seems the best way is that multi-bolt clearance hole idea.

I am torn on mandrel vs bolting to faceplate...my mandrel plan was to thread into one face with something smaller than the bearing, but sizable....then bore out the first bearing cup which is almost 2" in diameter...at that point I should be able to chuck it from the inside to hold it to do the other...having picked the stock up today & noting its mass, I am now considering bolting it on...I am concerned about getting it bolted up...wrestling my chuck on and off is difficult due to lack of clearance for the bolts.


So, the need is to turn bearing cups concentric with the outer? And this is an exercise in turning as well as a practical job?


yes & yes


Probably too late now but if it had been me I'd have welded some wheels up from a boss, a plate and a section of thick walled tube.
Quick cheap and good enough for a mower.

I wanted to take this approach, my father(owner of tractor) wanted solid steel, and quite frankly I wasn't going to argue with getting some big hunks of steel to play with:)


mtraven, do you have a three jaw or four jaw? If three jaw there should be two sets of jaws, one set with steps on the outside of center and one set with steps on the inside. One set will hold the ID of a tube and the other set will hold the OD of a tube. The jaws in a four jaw are reversible. That is, they can be removed and turned around so the steps are on the outside or the inside.
A 5" diameter chuck should be able to hold a 6" ID easily.

the 5" is a 3 jaw, I have a 4" 4jaw as well...I really thought it would be no problem too, but when I tried, I got real close & the jaws dropped out.


thanks again for all the help, its quite nice to hear from those with experience seeing how I have little.