Elliot 2G pedestal drill backlash question

Hi all, many thanks for the feedback on my question regarding the Prima clamp that came with an Elliot pedestal drill I've recently bought, sorry but I have another question regarding the actual drill, it's still disassembled and when set to direct drive (it has a two speed gearbox) I noticed there is quite a lot of backlash on the top pulley before you hear a clunk and the chuck actually starts to move one way or the other, the backlash is marked by the white stickers in the photo, about 1/4 turn which seems excessive to me, there is virtually no such backlash when the slow gear is engaged, could someone tell me if this is a fault or do I need to repair before I start to restore?

Thanks once again.

Paul, my Elliot has the same backlash as yours, and I've never got to the bottom of the cause. It's fine in the slow gear.

I have removed the quill in the past to replace the bearings, but was in a rush and couldn't figure out how to remove the top pulley to investigate the backlash (the quill winds out and leaves the pulley in place).

It has never caused me a problem, but if you don't wind the backlash out before you start the drill it can make a horrific clack as the slack is taken up.

Be interesting to hear if anyone has any ideas.

Andy

Hi Paul

Agree with Andy, mine's the same ..... I've used the drill for probably 30 years, probably in the same condition, and I don't think it's any worse now that it was when I got it. And I've certainly given it some hammer.

When I bought it I changed bearings and the large tufnol gear in the gearbox, so, although I cannot really remember, I'm sure I would have removed the backlash at the time if I could have. So I have a suspicion that it may have been designed like that.

I'm guessing that it's clearance in the dogs that engage the gears. Loads of clearance would make it easier to engage I suppose.

So, my recommendation is don't worry, just enjoy it, they are wonderful machines, built like brick outhouses !!

Cheers - Will

I also have an Elliot 2G, I bought it around 20 years ago and it also has always had a large amount of backlash when it the high range. I have always done as Andrew mentioned, and just wind the chuck backwards before switching on to take up the slop to avoid the sharp loud clunk.

When the low range backgear is engaged there is only a small amount of backlash.

Many years ago I did remove the gearbox cover and couldn't find any wear or broken parts, so I think it may be just the way they are made.

A few years ago I bought a three phase motor and VFD for it, and these can be programmed to give a very gentle startup and acceleration up to speed. So, as well as other benefits, that should remove the need to wind the chuck back before starting, once I fanaly get it fitted.

Edited By Lathejack on 07/01/2017 18:16:55

Edited By Lathejack on 07/01/2017 18:23:08

Ah OK, thanks everyone, that's reassuring to know.

Regards

Paul

OK calling on you knowledgeable folk once again, I'm looking to replace the original three phase motor with a single phase so I can use the drill in my home workshop, I've purchased a suitable single phase Crompton Parkinson motor, but its got a fault and I can't see what's causing it. The problem is when powered up and running its making an awful knocking noise, but when power is cut although the motor is still spinning the noise goes (see video clip below).

I've dismantled it expecting to find some fouling of internal parts but its all fine, also the bearings which are sleeve bearings seem ok, I say seem ok but maybe the power of the motor can cause play that I can't replicate.

Any suggestions appreciated, thanks Paul

https://youtu.be/E8h_XCk5Lao

Got my dad to take the motor apart and it's a faulty bearing.

Hi all, just found this post which has answered my question with regards to the backlash in the drill I just bought. If Paul Matthews is still on here I am interested to know if you needed to change any of the electrics on the forward and reverse switch when you changed the motor from 3 phase to single phase? I am hoping to do the same with mine.

Thanks

Jim

Yes you will need to change the switch wiring to suit single phase. There are previous threads on here about such wiring with cicruit drawings etc for single phase motors and reversing switches.

Don't!

Exhaust the VFD option first, even if it means digging out the star point. I paid a fortune for a new B56 framed imperial single phase motor for my meddings (the motor pulley did look like it would take the larger shaft of an 80 frame) only to swap back to the original 3 phase motor and a VFD a couple of years later.

The 3 phase motor is so much smoother not to mention easier to control (signal cables not mains to the switch gear). Wiring up a 3 phase barrel switch for reversing single phase can be done but I ended up with loads of stiff cable that was difficult to route. If I'd understood how easy it can be to find the star point and reconfigure an old 3 phase motor id never have gone the single phase route in the first place.

The other thing about a VFD/3 phase motor is that you can have a slow start-up that will take up any backlash without a massive clunk. Judging by the earlier posts that would be a welcome thing.

Martin C

Many thanks for your answers everyone.

I did look at a VFD after I posted on here mainly due to the cost of a new motor that runs at the right speed. Looks like I can get a VFD cheaper than a new motor. The slow start also sounds good as I know we will forget to move the chuck each time we use it. If anyone has any recommendations for a VFD to use that would be much appreciated. I will let you know how I get on.

Many thanks.