Bearings for HEQ5 Pro

[teoria_del_big_bang 698]

With the recent poor viewing I have decided to strip down my HEQ5 pro mount and upgrade the bearings and add the Rowan belt modification.

From threads I have looked at on this forum and also looking at the Astrobaby guide I think I need the following bearings, I know many on here have already upgraded the bearings so thought I would just check they are correct before ordering.

 

I have ordered rubber seals in order to prevent moisture ingress. Now I know these tend to make them run slightly tighter than metal seals but they do not run at speed so though they would be better. Any thoughts?

 

Steve

Edited January 24 by teoria_del_big_bang

[teoria_del_big_bang 698]

Without spending too much more is there anything else I should be attending to to improve the mount?

Steve

[Skipper Billy 2,612]

Good quality grease - I used 'Superlube' and it worked brilliantly even at very low temperatures.

[vlaiv 2,909]

I can't remember exactly, but you list does look right - there are three distinct types: small ones that go on worm shaft, large ones that go on main shafts (RA and DEC) and conical one that goes on dec where CW shaft extends.

I just took mine with me, went to local shop - showed them to the guy and said "I want the best ones like these" - he gave me bunch of SKFs

Further "mods" that you could consider would be better tripod (if not pier mounted) and saddle plate.

There is one "trick" you might want to try also - but involves just settings. DEC axis can have different amounts of backlash depending where on "circle" you are checking - and if you remove backlash where there is plenty - you will get stiff motion on opposite side. If you adjust where is little backlash you might still get some backlash on other side. If this happens - you can actually determine range of DEC motion that you are likely to use with your mount - you are likely to go below equator on south side, but you are not likely to hit anything close to horizon on north side, so it is likely that DEC won't do full 360 rotation in use (it might do even less if part of sky is not accessible from your location). Place problematic part of DEC where it will not be used by turning it either by hand (worm wheel when mount motor cover is off) or in EQMod - by slewing to that position and then resetting motor position to home (not parking to home but resetting to home - if you have done PEC, make sure you don't do slew in RA - keep it as is - in home position). Return scope to home by undoing clutches.

[wxsatuser 4,876]

Looks about right to me, don't see any problem with rubber sealed bearings.

Don't over tighten the taper rollers, they should run smooth with no play when you rock or pull on the shaft.
Watch the endfloat on the tiny worm bearings, again run smooth with no pinching and no rock in the shaft.
Take your time adjusting the backlash in each worm

Some of the old 6006 bearings on mine were really rough from new, glad I did the overhaul.

It's a great mount when the bearings are done and the Rowan mod is complete.
 

Edited January 25 by wxsatuser

[teoria_del_big_bang 698]

Thanks for all the help and other advice (much appreciated).

I am pretty confident now I have the correct bearings and will order today. 

All in all cost me about £56 for good quality bearings. I think that is a small price to pay. I have some "SuperLube" for the roller bearings and anything else that needs it, the others bearings are greased for life and sealed so should be okay

Will be ordering all but the smaller ones for the worm shaft from www.bearingsrus.co.uk as they were far cheaper than others I found, postage was extra but under £2, and still SKF and Timken for the tapered rollers.

The smaller ones for some reason were cheaper from simplybearings.co.uk and free postage.

The Rowan belt mod will be ordered from FLO of course.

Good point @vlaiv but I hope to at least get a pier built this year if not a small obsy (usually my plans for the year take several though so not holding my breath  )

 

Hopefully then I have a good platform for imaging, pity I can't fix the weather in the UK so easily  

Steve