A lay shaft reducer for the 7x14 lathe.

[modeldozer]

Hi everyone,

When I was turning the ER25 chuck and the hand wheel from large diameter steel I realized I would need to add more reduction to the lathe drive train to get better torque.
The design and build is being done as I am proceeding and adapted to materials on hand.

Started with a piece of 40mm square HRS and some round bar.



The square bar was squared up and cut to size on the mill.









Setup square on end and finished with a fly cutter

.

The shaft hole was marked out, located and drilled through.





A bearing seat was bored.



Then it was flipped over and the other bearing seat bored.



Mounting holes was drilled and tapped to coincide with the original motor in the lathe.



Next, keyways was machined in the ends of a piece of 8mm round bar to form the shaft.



The shaft support finished.



Another chunk of square bar was sawn and machined to form a spacer for the support.







For the new motor mounting a piece of 25mm calibrated square bar was setup and edges located on the mill.





And the motor radius was machined on one side using the boring head.



Forgot to take photos of the rest of the bracket's procedure.
Drilling and spot facing holes in a piece of 12mm shaft.



And together they form the motor mounting.





Drilling and reaming some holes in the fixing clamps.



All mounted on the lathe.





As part of the reassembly process, the hole in the aluminium cover for the belt drive was bored bigger so it can fit over the tachometer disc on the spindle.





Now waiting for belt and pulleys to arrive.  There will be three different pulleys on the lay shaft and the motor can slide in the clamps to align with any of them.  Will start wit 2:1, 1.5:1 and direct ratios and see how it works.

Next, as part of this mod I will also add extra support to the rear of the headstock.

Cheers for now.
Abraham

[Rob.Wilson]

Hi Abraham 

Nice going    , all this  modding too the lathe will make it  a cracker when your done    , I see your making good use of a gudgeon pin as a cylindrical square 

I noticed a few shots on this and other posts of  a boring head , did you make it ?


Cheers Rob

[modeldozer]

Hi Rob.

Thanks, heres hoping all the mods make for a usable lathe.

Gudgeon pins are thanks to my previous ocupation.

The boring head was done by me, see http://madmodder.net/index.php/topic,8375.0.html

Cheers
Abraham

[loply]

Abe,

That's a nice piece of work and will no doubt work a treat.

I do wonder though, why not just fit a larger pulley onto the spindle? If you cut away a little bit from the aluminum cover you can put a very large pulley in place of the original, thus saving the need any lay shaft.

I did this on my old 7x14 and got the top speed down from 1,110rpm to around 650rpm, so almost halved it (or doubled the torque).

Cheers,
Rich

[modeldozer]

Hi Rich,

the resons for the layshaft route are,

can have more than one ratio .

and it gives me room to ad much needed support to the rear of the headstock.

More to follow.

Abraham

[John Rudd]

Cracking job I think... despite the comments...

You go ahead and do your own thing Abe...great entertainment. 

[doubleboost]

Great looking mods
Very well shown
I have a couple of big gudion pins as well
John

[krv3000]

well dun good job

[modeldozer]

Hi John, john and krv3000,

Thanks for the encorragement.

Abraham

[modeldozer]

Hi all,

While I am waiting for the belt and pulleys to arrive I made the rear headstock support

Machined a piece of 10mm plate square and did a cutout in one side.



Made a half moon cutout at the top to go around the gear change lever.



The two pieces that will make up the support.



Drilling the holes to bolt the two together.





Set up the smaller piece and cut a chamfer at the outer top.





Drilled the holes to bolt it to the headstock, and a large hole for the cables to pass through.



And fitted to the lathe.  At the bottom it bolts to the heavy channel the lathe bed is bolted to.







Cheers
Abraham,

[modeldozer]

Good evening al modders,

The pulleys and bits finally arrived.



So I started a small production line to drill, ream and cut keyways in all the pulleys.
I used pulleys and a belt from my CNC router so I could use the lathe.  At 2:1 ratio it had a lot of torque, enough to ream the holes at 50 RPM without any difficulty.







Then it was over to the mill to drill and tap some holes for grub screws.



Then disaster struck when I broke the second tap in the large pulley.



The middle size pulley had its hub removed.  I could do facing cuts of 1mm at a time with no problem, something that was impossible in the past.



When I got around to remove the hub of one of the small pulleys, the lathe was striped down again, and not wanting to reassemble it, I cut it down in the mill with a fly cutter.



All done.  The 2:1 ratio is a bit slow for normal use so it was set on the 1.5:1 for now.







I have not used it much yet, but between the additional head support and increased torque there is a definite improvement.

Next up is a new guard for the motor.

Cheers
Abraham

[modeldozer]

Hi all,

I think I have come up with a design for the motor guard.  Had a few pieces of sheet cut by a friend.



After doing some cutouts the pieces was soldered together with plumbers tin solder.  Unfortunately my gas torch does not work well for doing this with silver solder.



Loosely fitted on the lathe.





Then made a hinge for it so it can be opened and closed easily.







Added a border at the top edge to prevent chips from entering.



And working on the lathe.





Still need to add some reinforcement and bits, more to follow.

Cheers
Abraham

[andyf]

Hi Abraham,

You might consider heat build-up inside the motor enclosure, and put some ventilation in there. David (Stilldrillin) has burned out a motor or two, so he fitted a computer fan. So did I. David's is in this thread:
 http://madmodder.net/index.php/topic,7560.0.html
and mine is shown here:
 http://andysmachines.weebly.com/motor-cooling-fan.html

Andy

[modeldozer]

Hi Andy.

Thank you for mentioning a fan, I will keep it in mind, especialy since I also cooked a motor.  Nothing burned, just lost all its power.

Cheers
Abraham

[modeldozer]

Hi everyone,

Finally had some clear whether to finish the guard.

Punched a hole for the power cable.





Build a fixing system for when it is closed.



And all done, painted and fitted.







Cheers 
Abraham

[Rob.Wilson]

Very neat and well finished Abraham , Well done   



Rob

[Stilldrillin]

Well done Abraham! 

Looking really professional. 

Don't forget Andy's tip, re. cooling fan. It makes a BIG difference........

David D

[andyf]

Very neat, Abraham. You are a lot better than me at folding up sheet metal.

Did you make your own toolpost? That thick central pillar looks as solid as a rock.

Andy

PS Don't forget the cooling fa...Oh, never mind!

[modeldozer]

Rob, David,

Thanks for the comments.

Andy,

The sheet metal was not folded, I cut all the panels and soldered them together.
The toolpost is self made, it is part of the QCTP amongst the Ralph Patterson plans on the tools and mods site.
Have not forgotten the fan, it will be part of the the phase of mods.

Cheers
Abraham

[dsquire]

Abraham

Even though I haven't been saying anything I have been following along with your mods. I think your doing a first rate job and it will pay you back every time that you use the lathe. Your next mod of some air flow around the motor will also help to extend the life of the motor.

Thanks for taking the time to do the photo's and explanations for us. I know it is time consuming on your part and the members do appreciate it. 

Cheers 

Don