A Wallaby of my own.

[steamer]

I need to make a broach now to cut the 1/16 keyway.  I get to use my keyway cutter again!

Dave

[Don1966]

 Nice job on the pinions Dave, you have been busy. Great come back on the fly cutter too. I will have to try my hand at cutting some gears. I want to make a set for cutting mm threads. My lathe is equipped with imperial cutting gears.


Don

[steamer]

Thanks Don!  I wouldn't have been able too without GailNM.   His spreadsheet is a great tool!   

A 37/47 cluster works very well as a metric transposition set.  It only has a .0002" millimeter error...so really it's better than most lathes.

Zee, no such thing as a bad question friend....Don't mind questions at all...by all means!

Dave

[swilliams]

Looks great Dave, was just reviewing how you made the flycutter way back on page 4, some handy info there.


The 37/47 cluster is a good one. Given suitable other change gears you can do a fair bit with a 21 tooth gear, upon recognising that 63/80 is extremely close to 100/127; 21 being a factor of 63.

Steve

[Don1966]

Dave I had made a spread sheet to calculate spur gears and checked it against on line calculators and it is spot on. The problem I have is my Myford is a screw cutting lathe. Not being very familiar with all of this. I am having trouble calculating the gears because of the change gear box. There is a chart inside the cover for metric and I have the manual but it is still difficult of me to absorb. The spindle gear is 30T, the tumbler reversing gears are 28/30, the tumbler sleeve gears are 24/30, the first stud gears are 19/57, the second stud gears are 19/57 and the lead screw gear is 72. Confusing enough the quick change gearbox to boot. As it is I can cut threads in imperial measurement and have. But not metric yet.

Don

[Jo]

Don,

The chart inside the Myford  change wheel guard refers to use of the metric conversion set. If you have not got a metric conversion set it is possible to cut the missing gears but you will also need a replacement change wheel quadrant (the bracket the gears mount on) as it is a different shape to allow for the gear clusters, see top left on page 51 of the manual. The last page in your Myford manual identifies the original metric conversion set, the later set (which I have) has 13 change gears in it.

For the silly money they sell for it could be worth making your own conversion set . 

Jo

[Don1966]

Jo my chart says I need 30T for the lead screw, tumbler stud gear goes from 28/30 which I have,to 35,40,45,55 and 60. Then it shows 1st stud 60T and 63T, 2nd stud 45T and 50T. This tells me I need a bunch of gears. The page in my book is page 31. The book I have is for the Super 7 without the quick change gear box. At least in don't see it. I also have the Ian Bradley series 7 manual. None of them show the quick change gear box.

Don

[Jo]

...... The book I have is for the Super 7 without the quick change gear box. ...... None of them show the quick change gear box.

Don

That explains why the table in the book is confusing you, the chart in the book it is for the standard change wheel set.  The S7B manual has  parts list at the back which covers the quick change box and the conversion set.

[Don1966]

That is what I have and thanks Jo, the last page of the book shows all the gears the chart is showing.

Thanks don

[Don1966]

I also went online and found a 712V manul for my gearbox and it shows all I need. I believe I will forget about metric thread for now. To many parts to change out. Thanks Jo and Dave.

Don

[steamer]

Still need to make a 1/16" cutter for the key way cutter....focusing on the SB this week.....patience....

Dave

[tel]

Still need to make a 1/16" cutter for the key way cutter....focusing on the SB this week.....patience....

Dave

A cut down jigsaw blade in a bit of bar will do the job.

[steamer]

Thanks Tel!   I'll keep that one in mind.

Dave

[Jo]

A cut down jigsaw blade in a bit of bar will do the job.

I like that idea

I wonder  taking your idea further... if you got a junior hacksaw blade and cut it into a number of short sections and put them together side by side, fitted into a shallow tapered slot....

Jo

[steamer]

Don't see why not...if you have a junior hacksaw blade.

I'll get a chance to do more on the beasty this weekend coming...once I'm done with lathe beds .....and verification and test protocals at work!   

Dave