HEQ5 Dec axis very stiff

[stem1989]

I've had my HEQ5 for around 3 months but only used it maybe 3 or 4 times due to weather, i don't bother using it if its looks patchy (i tend to use the EQ3-2).

Ever since getting it I have thought the dec axis is a little stiff...

for example if I am getting something in my finder with the clutches unlocked I find that moving in dec by hand isnt smooth at all, il push and nothing will happen and then all of a sudden it will jump quite a way.

Obviously the main issue is balancing, it takes a massive off balance for the dec to swing, making it very difficult to balance the dec axis.

Now having looked it seems I need to strip down and re-grease as they don't grease them very well in the factory, I've read the guide but is it an easy feat? I'm not very good with small parts, i tend to break things a lot when I mess with things.

Is there anything else it could be or is this likely a grease issue?

No issues with RA thankfully.

[Macavity]

My HEQ5 was fairly stiff, when new. I sense this would have worn off with use (and did) - As the lubricant redistributed etc. I partly dismantled my mount... and came to slightly regret it. Although this is WELL documented by AstroBaby, some of the parts were a tad reluctant to seperate and once apart, fiddy to reassemble. One of the shafts proved particularly difficult to reinsert into a cone bearing, in situ? This Cat (Macavity) nearly "had kittens" at that point.

Moreover, I noted that one of the "end bolts" NOW works loose more easily and the backlash is significantly increased. I feel I am now obliged to re-strip it and "do it properly". Perhaps the old adage, "if it ain't broke, don't fix it?". As you say, balance is important. A heavier / bigger scope can (paradoxically) HELP when moving the thing manually - Or establishing this balance.

[SnakeyJ]

Might not actually need a strip, perhaps just minor adjustment of the dec worm gear - definitely worth checking astrobabes guide on this prior to do the full strip and reassembly.

Good luck.

[dph1nm]

perhaps just minor adjustment of the dec worm gear

Surely with the clutch unlocked neither the worm nor the worm gear is actually in use? The mount casing should just spin freely round the Dec shaft.

NigelM

[SnakeyJ]

Surely with the clutch unlocked neither the worm nor the worm gear is actually in use? The mount casing should just spin freely round the Dec shaft.

NigelM

Good point Nigel - in this case if the DEC axis is stiff with the DEC clutch disengaged then worm gear alignment is not the issue. Steve, is it a new mount (under warrant) or did you get this s/h. Astrobabe's guides are very good to work through if you do choose to do this yourself (though easier with the right tools), or perhaps a dealer or other CLASS member might be able to offer assistance.

Sorry for any misdirection - Jake

[Astro_Baby]

If the clutch is unlocked the worms will have no effect. The first qustion I would ask is do you have the mount balanced well and the second question would be to check that when you relase the clutch does it stay released ? The clutches can slip a little nder the weight of the lever and sllowly close again. Not enough to lock the mount but enough to make it go a bit stiff.

Tye other problem could be that the clutch is too tight even when the clutch lever is in the off position. You could easily test this by removing the clutch lever, back out the brass screw underneath a bit, dont take it right out, and then try turning the DEC. if that frees it just put the brass screw back in and set the clutch lever at a point where its tight enough when put on but also loose enough when released.

Take a look at my strip down guide and it will give you the general idea.

Beyond the simple solutions above it may be that the lower cone bearing on the DEC shaft is too tight...thats not that hard to remove and adjust. Take a look at the guides on that.

I always tell people that although these mounts arent that hard to take to bits its best avoided unless you have some good tools and have a fair degree of mechnical nous and feel. Without a bit of a flair for amateur mechanics its probably a very miserable experience.

[stem1989]

Thanks for the replies guys, I will try those things tonight, i really dont want to take it apart. It was bought from FLO and Ive had great experiences with any issues with them, they are very helpful so if the problem persists i'll give them a call before I take it apart!

Hopefully some of the minor adjustments will help.

[valefor]

a bit more of a pain but i also had a stiff problem with my mount. but both axis's. i dissasembled the head recently, stripped the thick grease off (witch was thicker than hair putty) and regreased it with something much thinner. now it flys so smothly that even with my camera on the scope (witch puts the weight a little over the mount limit) the motors dont even struggle.

but if you do go down this path make sure you look up how to do it. i managed to do a little damage to mine as there was a hidden screw i didnt know about untill it was off. lol

but regrease or even without dissasembling it spray some wd40. that would make the greese thinner too.

good luck

dave

[russ.will]

I don't know if I'm remembering this right, but my HEQ5 was fine and then after reassembling it, it was stiff and juddery in the dec axis, exactly as you describe.

It turned out that the counterweight collar had been screwed in slightly too tight, prior to doing up the three set screws. I backed it off by a fraction of a turn, retightened the set screws and it was fine.

I can't recommend putting WD40 anywhere near a mount. It's a penetrative oil/water dispersant and is in no way shape or form suitable for use around high load bearing gears. It's also no good trying to make grease thinner with it, as it's impossible to judge how thin it will make it. Too thin and you'll be grinding metal. Personally, I use motorcycle chain lubricant. It stays stuck to the gears, is designed with very high pressure loading in mind and stays consistent over a very wide range of temparatures.

Russell

[Astro_Baby]

Counterweight collar is what holds the cone bearing in, thats what I meant above. Its quite likley thats whats causing this.

[Astro_Baby]

Ps domt go squirting wd40 into the mount....if you read my guide theres a section on the demon mount.....this was a miunt I rebuolt where somene had squirted various lubes into the mount. The effect was the lubes didnt mix, in some places the lubrication has turned to a gel and in others a mix of lubes had acted like a degaser causing stuff to seize. Many of the plastic shim washers had disintegrated and that MAY have been caused by certain lubricants though it was impossible to tell. Some lubes will eat plastic.

Lubrication of these mounts always splits the room but my advice would be as above...dont put wd40 into the mix. Its farught with perils.

The

lower done bearing is held in by the cone shaped casing around the top of the DEC ahaft, this is held on by a thread and secured with three grub screws around the casing. You will need an allen key to remove the grubs, just loosen them a bit and then unscrew the cone shaped casing a graction and see if that helps.

A word of cautio, after tightening down the grub screws its worth checking them periodically as they have a tendency to loosen up over time. I use some threadlock to hold mine in alternatly a small dab of suerglue will do as well.

[russ.will]

Good. My memory is better than I give it credit for!

Russell

[Daddystu]

I'm having this very problem with my mount now. Its not the counterweight collar.

[Daddystu]

I've sorted the binding using just a bit of patience and the set screw adjustment as described by astrobaby. I have side to side dec shaft play though which the set screws for and aft dont affect. There seems to be no external way of adjusting for this unless its the end float adjustment. Cant hurt to try.