|james short||12/07/2018 10:47:26|
|3 forum posts|
Hi I have just joined group ? and have purchased a Drummond M type lathe 1948 ,How do I engage back gear.I have read some ware that when altering the Bull gear you have to be careful not to over loosen the nut or it falls into the works ,any suggestions
|not done it yet||12/07/2018 12:34:03|
|2566 forum posts|
You will likely get your answer here, but do join the yahoo group for Drummond lathes - as much as I hate navigating any and all of the yahoo forums! Some good posters over there, other than the ones that frequent this forum as well.
2313 forum posts
If you have not yet done so look up www.lathes.co.uk - they have information about pretty nearly every lathe made. It may set you on the right course.
|David George 1||12/07/2018 20:22:22|
614 forum posts
Hi James I have an M Type and to change to back gear there is a slotted screw on the bull gear just loosen and rotate the bull gear with the button to the end of the slot. Then re tighten the slotted screw. You then rotate the back gear lever to engage the mesh on the gears rotate as you do to help engagement. Do the reverse to take out the back gear but after rotating the bull gear slot tighten the screw and importantly hold the chuck and by hand rotate the pulley to make sure that the spring loaded plunger has located you will hear and know when it is. If you need any further info send me a message and it is worth looking on my album's for info.
Edited By David George 1 on 12/07/2018 20:24:51
3144 forum posts
Welcome to the forum. There are quite a few of us M-type owners on here. Not sure which nut you are worried about falling into the works? If you mean the slot-headed screw on the front of the bull gear that you slacken to rotate the plate to engage/disengage the bull gear, it only needs to be loosened a quarter of a turn or less to allow the plate to be rotated around to the end of its slot. The screw is then retightened before starting the motor.
The main thing is to MAKE SURE the bull gear is disengaged from the pulley unit before engaging the back gear and starting the motor. When the bull gear is disengaged, but the back has not yet been disengaged, you should be able to turn the chuck or spindle by hand freely without the pulleys and belts moving. Once you can do that, engage teh back gear and start the motor.
3460 forum posts
I use a pair of longnose pliers in my right hand to gently pull on the brass pin then my left hand thumb shoves the knurled screw clockwise while my left hand fingers hold the outer rim of the bullwheel
this pushes the inner plate forwards to wedge the pin out and disengages the bullwheel from the pulley, making the backgear system available
Reverse the procedure to go direct drive again
Edited By Ady1 on 13/07/2018 09:14:39
|Adrian Harrison||04/01/2019 05:37:20|
|38 forum posts|
so the slotted screw needs to be tighten and loosen when engaging and disengaging the bull gear?
3144 forum posts
Yes. Loosen the slotted screw half a turn or so then rotate the plate around so the face cam action pulls the pin outwards and disengages the bullwheel (gear) from the 3-step pulley. Then tighten the slotted screw again.
The plate you turn should have either a small knurled knob sticking out that you push on with a screwdriver to rotate the plate. Or there will just be a small hole in the plate if the knob has fallen out over the years.
You will see the plate has a slot in it that the screw sticks through. You rotate the plate so the slot moves all the way to one end or the other.
Once the plate has been rotated so the drive pin is pulled out, and slotted screw retightened, you should be able to spin the chuck or spindle without the 3-step pulley rotating if its held by hand. This means the direct drive is disconnected. Then you can swing the back gear into mesh with the two gears - the bullwheel gear and the small gear at the other end of the 3-step pulley.
Once you do that, you should be able to pull on the belts to rotate the 3-step pulley on the spindle and the spindle/chuck will rotate slowly. If it is all locked up, you have not disengaged the drive pin properly, so don't start the motor untill you can turn things over by hand first.
|Nicholas Farr||04/01/2019 08:06:10|
1730 forum posts
Hi, according to the Drummond user manual, **LINK** (pages 4 & 5) there is no need to undo or retighten any screws to disengage/engage the direct drive. My Myford version will disengage/engage just as the manual describes.
3460 forum posts
I keep them loose myself, but you've got to watch that none of them come out too far or they start to catch on the main headstock housing
A light finger tightness works for me
|Adrian Harrison||05/01/2019 04:06:15|
|38 forum posts|
ok thanks.. with mine I have never moved any screws but it does work as it should so i will make sure nothing is lose
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