-
Welcome back Guest! Did you know you can mentor other members here at H-M? If not, please check out our Relaunch of Hobby Machinist Mentoring Program!
Burke No. 0
- Thread starter Gary Ayres
- Start date
- Joined
- Jul 2, 2014
- Messages
- 107
Cheers Phil 
)
)
- Joined
- Jul 2, 2014
- Messages
- 107
I bought a V-belt step pulley which I had to machine to fit. First of all, widening the bore to fit the spindle:
Then turning off the widest pulley (as the whole thing was too big to fit in the 'throat' of the mill):
- - - Updated - - -
And now, a question.
Please see photo below. In order to hold the spindle in position and stop it from sliding back and forward I'll obviously need to screw some kind of nut or threaded collar on the back end of it. However, that will move with the spindle and rub against the static face of the bronze bearing housing. Can any of you guys advise me of the best thing to use as a washer or spacer to minimise friction between the collar and the bearing? I have acetal, bronze, brass, steel... and I think I have also heard of someone using some kind of fibre washer. Or is it ok just to let a steel collar run against the bronze? I have a similar issue with the collar at the other side of the bearing. Advice appreciated! :thinking:
Then turning off the widest pulley (as the whole thing was too big to fit in the 'throat' of the mill):
- - - Updated - - -
And now, a question.
Please see photo below. In order to hold the spindle in position and stop it from sliding back and forward I'll obviously need to screw some kind of nut or threaded collar on the back end of it. However, that will move with the spindle and rub against the static face of the bronze bearing housing. Can any of you guys advise me of the best thing to use as a washer or spacer to minimise friction between the collar and the bearing? I have acetal, bronze, brass, steel... and I think I have also heard of someone using some kind of fibre washer. Or is it ok just to let a steel collar run against the bronze? I have a similar issue with the collar at the other side of the bearing. Advice appreciated! :thinking:
- Joined
- Jul 2, 2014
- Messages
- 107
I decided to try fibre washers as I reckon that they will wear out before anything else does and are replaceable. However, after I go them someone recommended surface ground steel, which I will try if I have any issues with the fibre ones.
- - - Updated - - -
The washers problem is pretty minor in comparison to my next question. The nut at the back of the spindle is the only thing that appears to be missing from this machine. It appears to be 15/16" x 20 tpi, which - in my part of the world at least - is about as non-standard as it gets. It's a very fine and shallow thread. As it's an American machine, is it likely to be a UNS thread? If so, there's a tap for sale which I think meets the spec. If possible, I'd rather use a tap than try to cut it on the lathe. Would very much welcome your thoughts on this...
- - - Updated - - -
The washers problem is pretty minor in comparison to my next question. The nut at the back of the spindle is the only thing that appears to be missing from this machine. It appears to be 15/16" x 20 tpi, which - in my part of the world at least - is about as non-standard as it gets. It's a very fine and shallow thread. As it's an American machine, is it likely to be a UNS thread? If so, there's a tap for sale which I think meets the spec. If possible, I'd rather use a tap than try to cut it on the lathe. Would very much welcome your thoughts on this...
- Joined
- Jul 2, 2014
- Messages
- 107
Have decided to cut the thread on the lathe. Time to learn a new skill...)
)
- Joined
- Feb 2, 2013
- Messages
- 3,916
thanks for starting the thread, it's very interesting to see the lil machine coming together!
all the best
mike)
all the best
mike
)
- Joined
- Jul 2, 2014
- Messages
- 107
Thank you Mike.
gary
gary
- Joined
- Jul 2, 2014
- Messages
- 107
At risk of seeming inconsistent I have changed my mind and am going to try the tap option for the spindle nut.
Reasons:
I have decided to learn to cut threads on the lathe soon, but will start with metric ones...
Reasons:
- I just remembered that both my lathes have metric leadscrews
- A 15/16" x 20 tpi tap was available on ebay UK for GBP 18 (31 US Dollars) including postage.
I have decided to learn to cut threads on the lathe soon, but will start with metric ones...
- Joined
- Dec 19, 2012
- Messages
- 38
Hi Gary, I was looking over the pictures of the complete mill and yours and wonder about a coupe of things. You mentioned that you wanted to make this nut and a backing washer/shim to keep the spindle from backing out. I'm wondering if the pulley assemble with hardened washers against the inside edges of the spindle supports actually hold the spindle in place? The bolt hole or flat on the spindle looks like where the pulley locks in place.
Also the threaded end, in the picture of a completed machine kind of looks like an adapter for a collet closer? I would think you need something there to hold cutters? Maybe it is missing a draw-bar?
Just my ramblings, maybe relevant maybe not, lol
Cool machine, and a cool project.
Mark
Also the threaded end, in the picture of a completed machine kind of looks like an adapter for a collet closer? I would think you need something there to hold cutters? Maybe it is missing a draw-bar?
Just my ramblings, maybe relevant maybe not, lol
Cool machine, and a cool project.
Mark
- Joined
- Jul 2, 2014
- Messages
- 107
Hi Mark -
thanks for all your good thoughts.
It's possible that in the original machine the pulley cone (which would have been 3 flat belt pulleys) played a part in holding the spindle in place. And yes, the hole in the spindle is where the grub screw holding the pulleys would have rested. However, the pulleys were missing from the machine when I bought it. I'm using a v-belt step pulley which is probably shorter so if I were to follow your suggestion some spacers would be required and I think that could work.
That said, the spindle will not slide out towards the back end of the machine because the front bearing is tapered (as is the front end of the spindle, to match). The only way that the spindle will slide out is forward, so if I were to use something on the insides of the spindle supports to prevent this it would have to be against the inside of the front bearing. That would leave the rear end of the spindle 'floating', if you follow me, so I think that plan A might still be the one to try first, i.e. the spindle is held in place by the taper on the front bearing and a nut or collar on the outside of the rear bearing (i.e. where the thread is).Actually, I have just looked and someone on the other forum I am discussing this on has suggested the use of two locking collars, one fore and one aft of the rear bearing, with the tapered front end of the spindle floating in the front bearing with a tiny amount of play.
Yes, it's definitely missing a drawbar - something I'll have to make. However, don't know if I'm understanding you correctly or not, but the threaded end is at the rear. I guess it would have been threaded either for something to tension the drawbar with, or for a spindle locking nut. The front end takes Brown and Sharpe #7 collets. At least I hope it does, because I have just ordered a set from your side of the Atlantic!
Great to know, Mark! Thanks for your encouragement)
gary
thanks for all your good thoughts.
It's possible that in the original machine the pulley cone (which would have been 3 flat belt pulleys) played a part in holding the spindle in place. And yes, the hole in the spindle is where the grub screw holding the pulleys would have rested. However, the pulleys were missing from the machine when I bought it. I'm using a v-belt step pulley which is probably shorter so if I were to follow your suggestion some spacers would be required and I think that could work.
That said, the spindle will not slide out towards the back end of the machine because the front bearing is tapered (as is the front end of the spindle, to match). The only way that the spindle will slide out is forward, so if I were to use something on the insides of the spindle supports to prevent this it would have to be against the inside of the front bearing. That would leave the rear end of the spindle 'floating', if you follow me, so I think that plan A might still be the one to try first, i.e. the spindle is held in place by the taper on the front bearing and a nut or collar on the outside of the rear bearing (i.e. where the thread is).Actually, I have just looked and someone on the other forum I am discussing this on has suggested the use of two locking collars, one fore and one aft of the rear bearing, with the tapered front end of the spindle floating in the front bearing with a tiny amount of play.
Yes, it's definitely missing a drawbar - something I'll have to make. However, don't know if I'm understanding you correctly or not, but the threaded end is at the rear. I guess it would have been threaded either for something to tension the drawbar with, or for a spindle locking nut. The front end takes Brown and Sharpe #7 collets. At least I hope it does, because I have just ordered a set from your side of the Atlantic!
Great to know, Mark! Thanks for your encouragement
)gary