NEQ6 Play in RA after Belt Mod

[Spoon]

hi all,

i did the belt mod on my neq6 the other day and after reassembly i found that there was a lot of play in the RA, so i stripped it down again and found that the RA worm bearing nut had come loose so the worm was moving the the worm carrier hence the play, however after tightening it all up and reassembly there was a lot less play but still enough to cause backlash, more so that with gears, i can't literally tap it from side to side. I've followed AstroBaby's instructions to the letter on worm adjustment so i don't think its that, but i can't find anything else it could be. any ideas?

Cheers in advance

Cam

[Tinker1947]

I got rid of a bit of backlash by cutting a feeler gauge to fit in the other end so worm carrier can't move back and forth, feeler gauges are cheap bit of trial and error getting the thickness right, to thick causes binding...bung some grease in there as well...

[Spoon]

I got rid of a bit of backlash by cutting a feeler gauge to fit in the other end so worm carrier can't move back and forth, feeler gauges are cheap bit of trial and error getting the thickness right, to thick causes binding...bung some grease in there as well...

i put plenty of TF2 Lithium Grease in. I might just strip it down again and see where its coming from 

cam

[sloz1664]

NEQ6-Belt-Kit.pdf

Hi Cam,

Did you use the Rowan Belt Mod or source the parts yourself.

If sourced, review the instructions attached:-

Astro Baby's strip down & rebuild instructions are superb but the Rowan instructions are aimed at the belt mod.

The only issues I can see are:-

Not in any preferential order....

RA Worm Shaft end float:  Remove cover and whilst rocking RA from side to side feel for any play. Adjust to suit

RA Worm -Wheel mesh adjustment:   With the RA axis clutch locked take hold of the axis and ‘feel’ for play in the worm wheel mesh. Adjust to suit

Other issues could be:-

Loose RA Worm Shaft Pulley. Should be held with two grub screws.

RA Belt tension. I tensioned the belt using a screwdriver to lever against the motor and nipping up the cap screws using an allen key.

Loose RA motor.

Steve

[Spoon]

NEQ6-Belt-Kit.pdf

Hi Cam,

Did you use the Rowan Belt Mod or source the parts yourself.

If sourced, review the instructions attached:-

Astro Baby's strip down & rebuild instructions are superb but the Rowan instructions are aimed at the belt mod.

The only issues I can see are:-

Not in any preferential order....

RA Worm Shaft end float: Remove cover and whilst rocking RA from side to side feel for any play. Adjust to suit

RA Worm -Wheel mesh adjustment: With the RA axis clutch locked take hold of the axis and ‘feel’ for play in the worm wheel mesh. Adjust to suit

Other issues could be:-

Loose RA Worm Shaft Pulley. Should be held with two grub screws.

RA Belt tension. I tensioned the belt using a screwdriver to lever against the motor and nipping up the cap screws using an allen key.

Loose RA motor.

Steve

Hi,

I used the Rowan one, got it for a good price at the IAS. I can't find where it's coming from. Would really help if the worm carrier was transparent!

Cam

[1parsec]

Hi Cam,

How much side to side movement is there ?  Where do you see the movement and is this noticed when you move the axis by hand or with the controller ?

If the RA is moving sideways and not in a rotational sense, is could be the RA locking nut is loose and allowing the RA axis to wobble. See step 25 in the instructions.

Also if you strip the mount down, it is essential to remove the motor from the mount before separating the axis otherwise the belt may (will)  be damaged.

Dave.

[Spoon]

Hi Cam,

How much side to side movement is there ? Where do you see the movement and is this noticed when you move the axis by hand or with the controller ?

If the RA is moving sideways and not in a rotational sense, is could be the RA locking nut is loose and allowing the RA axis to wobble. See step 25 in the instructions.

Also if you strip the mount down, it is essential to remove the motor from the mount before separating the axis otherwise the belt may (will) be damaged.

Dave.

Hi, it's not a lot at all, but if I tune the worm carrier I can remove the play but then there is some binding, but tuning out the binding loosens the RA

Cam

[1parsec]

Hi, it's not a lot at all, but if I tune the worm carrier I can remove the play but then there is some binding, but tuning out the binding loosens the RA

Cam

Hi Cam,

I would back off the mesh on the worm wheel then gently tighten the worm end float adjustment ring. Then set the worm wheel mesh again..

Dave.

[Spoon]

Hi Cam,

I would back off the mesh on the worm wheel then gently tighten the worm end float adjustment ring. Then set the worm wheel mesh again..

Dave.

Will do

Thanks

[Spoon]

Hi Cam,

I would back off the mesh on the worm wheel then gently tighten the worm end float adjustment ring. Then set the worm wheel mesh again..

Dave.

Nope that wasn't it now I can't get the mount back into the bit that says NEQ6 on it

[malc-c]

By the sounds of things it would seem that the original gearing was such that it prevented any lateral movement in the worm.  Now with the belt kit, the pulley's position means that the worm is free to move.  If you are not able to remove the rubber bung and adjust the endfloat then you will need to strip the mount and make the required adjustment.

My experience with an HEQ5 is that getting the optimum meshing of the worm, and getting minimum amount of backlash is a very narrow band.  It takes hours of making small adjustments of the grub screws.  I did find that the metal used to cast the mount is soft and I had to replacace the grub screw with a longer one as the thread at the bottom of the hole had stripped through over-tightening, and thus the orginal wasn't actually making any pressure on the carrier.  Make sure you back off one side before tightening the other.

[Spoon]

By the sounds of things it would seem that the original gearing was such that it prevented any lateral movement in the worm. Now with the belt kit, the pulley's position means that the worm is free to move. If you are not able to remove the rubber bung and adjust the endfloat then you will need to strip the mount and make the required

What rubber bung? I've only got metal end caps covering the end float. That is as long as I'm not getting my parts mixed up.

Cam

[malc-c]

On my HEQ5 they are like a hard rubber / plastic cap.  Looking at an image of an EQ6 these are the caps I was referring to.  They may well be metal on an EQ6, and may unscrew rather then pull out, I don't know as I don't have that mount.

Underneath them is the end of the worm shaft, with a keyed nut.  You'll need a couple of screwdrivers or a pair of long nosed pliers to twist it to take up any endfloat in the worm

[Spoon]

On my HEQ5 they are like a hard rubber / plastic cap. Looking at an image of an EQ6 these are the caps I was referring to. They may well be metal on an EQ6, and may unscrew rather then pull out, I don't know as I don't have that mount.

Underneath them is the end of the worm shaft, with a keyed nut. You'll need a couple of screwdrivers or a pair of long nosed pliers to twist it to take up any endfloat in the worm

Hi,

I've tightened them up as much and I can and there's no play in the worm but there's still play somewhere in the system

Cam

[Spoon]

On my HEQ5 they are like a hard rubber / plastic cap. Looking at an image of an EQ6 these are the caps I was referring to. They may well be metal on an EQ6, and may unscrew rather then pull out, I don't know as I don't have that mount.

Underneath them is the end of the worm shaft, with a keyed nut. You'll need a couple of screwdrivers or a pair of long nosed pliers to twist it to take up any endfloat in the worm

Hi,

I've tightened them up as much and I can and there's no play in the worm but there's still play somewhere in the system

Cam

[r3i]

On my HEQ5 they are like a hard rubber / plastic cap.  Looking at an image of an EQ6 these are the caps I was referring to.  They may well be metal on an EQ6, and may unscrew rather then pull out, I don't know as I don't have that mount.

Underneath them is the end of the worm shaft, with a keyed nut.  You'll need a couple of screwdrivers or a pair of long nosed pliers to twist it to take up any endfloat in the worm

Hi Malc,

The caps are indeed metal and screw in on the NEQ6.  They have 2 holes in them and you need needle nose pliers or such like to unscrew them Unless you're very careful or very lucky, it's all too easy for the pliers to slip and scratch the black paintwork on the cap.

[Spoon]

Exactly like I did, so I'm going to order new ones

[r3i]

Exactly like I did, so I'm going to order new ones

Welcome to the club ,  I've just left mine as is, as no doubt it will happen again at some stage. 

[sbooder]

I take it there is enough pressure on the RA taper bearing?  People seem to want to leave these loose but they are meant to be under pressure.  If not then it will be the fine balance of worm mesh and float, this can take hours to get spot on when you first rebuild.

[Spoon]

I take it there is enough pressure on the RA taper bearing? People seem to want to leave these loose but they are meant to be under pressure. If not then it will be the fine balance of worm mesh and float, this can take hours to get spot on when you first rebuild.

I've tightened the black ring holding it in as much as I can and still nothing. The Dec took about 30 seconds to tune!

[sbooder]

I can't think what else it would be other than the relation between worm mesh and float.  I will think on.

[1parsec]

Hi Cam,

Referring to step 19 in the instructions.   The gap between the side of the 47T pulley and the inside wall of the casing is essential so that there's no binding.

It could be that when you tighten the end float adjustment it's pushing the worm shaft to this end and it is causing the pulley to rub.

You can check this without stripping the whole mount down:-

Remove the RA motor from the inner housing. This will allow you to turn the end of the worm shaft more easily.

Loosen the end float adjustment ring a couple of turns and make sure the end cap at the other end of the worm is fully screwed in and gently tightened.

Now screw in the end float adjustment ring to take out the end float and at the same time turn the worm and check the worm remains smooth to turn.

If the worm shaft become noticeably stiff to turn or locks tight, then it's the pulley rubbing and you'll need to strip down to set the position of the pulley with clearance to the casting. 

Cheers, Dave.

[sbooder]

Hi Cam,

Referring to step 19 in the instructions.   The gap between the side of the 47T pulley and the inside wall of the casing is essential so that there's no binding.

It could be that when you tighten the end float adjustment it's pushing the worm shaft to this end and it is causing the pulley to rub.

You can check this without stripping the whole mount down:-

Remove the RA motor from the inner housing. This will allow you to turn the end of the worm shaft more easily.

Loosen the end float adjustment ring a couple of turns and make sure the end cap at the other end of the worm is fully screwed in and gently tightened.

Now screw in the end float adjustment ring to take out the end float and at the same time turn the worm and check the worm remains smooth to turn.

If the worm shaft become noticeably stiff to turn or locks tight, then it's the pulley rubbing and you'll need to strip down to set the position of the pulley with clearance to the casting. 

Cheers, Dave.

I think I remember having to do that when I first did the mod Dave.  I kept the gear wheel tight to the butt of the worm shoulder with a screwdriver as I nipped up with the small alan key.

[Spoon]

new problem now, got the mount back together but the RA is really stiff even without to locking bolt in the mount, what could be causing this? 

cam

[sbooder]

Redo your taper bearing, if this is in crooked it will cause the problem you have.  When you say locking bolt, do you mean clutch?