| serse |
Sounds like an old story, but...
I am intending to rewire a RB250 with the Incognito kit. Lurking around, I found this paper which seems of some interest :
http://www.tnt-audio.com/sorgenti/analogue_bits_e.html
But I also found this one and got a bit puzzled by the warnings :
http://www.william-reed.net/audio/rega1.html
I've noticed that according to the first author, rewiring a RB300 and a RB250 seems to be slightly different ; I quote :
"Having the main tube apart allows easy access to the tiny hole the wires are supposed to go through. Believe me, this sure beats messing around with a pull cable (as still is required for the RB-250, by the way!)"
So... Can I apply the first procedure to the RB250 and remove the arm tube ? I wouldn't want to destroy the bearings in the process, even though I don't really see where is the problem...
Thanks
Pascal |
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| sreten |
Hi,
the procedure for removing the arm tube in the first post
can't be applied to a RB250 as the yoke is very different.
:)/sreten. |
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| serse |
Ok, thanks Sreten. Seems I will have to play with a kind of "fishing" wire...:rolleyes:
Hope the result will worth the hassle !
Pascal |
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| jeff spall |
Hi, that second link is mine, and I really do recommend not taking an RB250 apart!
The very easiest way is to prepare for the re-wiring *before* you remove the old wire. Tie some fine thread to the old wire and pull it through, then you have the thread ready to pull your wire through with.
If you have to start with a bare arm, then the best method I've found is to strip a single core of Cat5 wire which is about the right stiffness to thread through. With the stub out, you can start at either end, but the base is easiest.
Once the Cat5 is through, you can either solder the wires to it and pull them through from the base, or use the Cat5 to pull some thread through and use that to pull the wires. I find the second method can work best.
If you're using the Incognito loom, you'll only have to do the cartridge tags as all the rest of the work is already done, so it's a fairly easy job.
regards, Jeff
PS, Although the RB300 just unscrews, the bearings were originally set up using a jig and there's no really accurate location for the two bits of Yoke (like dowell pins) so the chances are that you may not be able to replace them as accurately as originally. Bearing alignment and loading are really critical to performance. |
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| serse |
Hi Jeff,
Thanks for your comments. Actually I had a slightly different method in mind : I was intending first to remove the existing counterweight and stubshaft (as I have to do it in order to install the Michell TecnoWeight...), then to introduce the Incognito wire from the base, to get the wires from the rear of the arm and to pull them (gently) along the tube with a very thin stick of bamboo (as suggested by someone ).
What do you think ?
Regards
Pascal |
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| jeff spall |
Hi, It might be hard to get the wires up the vertical tube from the base by pushing rather than pulling as they'll tend to bunch. Also, there should be a tiny rubber grommet at the top of the tube making it much more difficult (but that often gets displaced when de-wiring the arm. Pulling through on thread or wire is very easy once you have the thread in place and there's very little chance of damaging the very delicate wires.
regards, Jeff |
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| graeme uk |
Ive been wanting to take my rb250 apart for a while so i can strip and drill the arm tube.
What is so difficult about taking them apart?
Ive read your warnings but dont see the problems as ive never tried. |
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| jeff spall |
"What is so difficult about taking them apart?"
Nothing hard about taking them apart, just putting them back together as you will definitely ruin the bearings and damage the brass stubs.
I've done six RB250s and never been able to get those stubs out without damaging them. They are in very tight and the brass is very soft, so you damage the screw slot badly. Unless you can devise and make a rather precise little puller to act only on the outer race, you have to drift the bearings out, which seriously trashes them.
The yaw bearings in the brass body can usually be left in place whilst their shaft is taken out, but replacement is so easy you might as well change them. Alignment and loading of the bearings is *very* critical, as I've found to my cost and there's not really a chance to adjust them afterwards. I really wouldn't want to tackle setting up new bearings using the standard Rega location method. I now make every component from scratch keeping only the arm tube, 'cos proper bearing location is easier that way!
Replacement bearings are about £4 each from RS components and all 4 are the same. do resist the temptation to try high-precision bearings in standard Rega mounts as the location isn't accurate enough for them and the results will be far worse than ABEC3 bearings. The RS ones are ABEC5 which is a bit tighet for this application, so running them in well before installing them is well worth the effort. |
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| serse |
Hi Jeff,
I had a look on your site. Quite impressive. I like very much your counterweights, especially the low-cg one.
Is it just a one-shot project for your own personal agreement or do you intend to offer some of these modifications on a (even informal) commercial basis ?
Pascal |
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| graeme uk |
thanks jeff, as a man with way more experience than me ill take your word for it.
I only wanted to take mine apart to remove the paint.
I have been mesing with adding clips to the arm tube to reduce resonace with good results, so ive been thinking about drilling the arm tube to make the mod more permenant.
Any tips?
What would work best, your spiral way, or OL's slots?
Would a row of different size holes in the underneath of the arm work? |
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| jeff spall |
Hi, since putting those pages together, I've been working on a design where the bearijng housings would be adjustable, allowing really high quality, close tolerance ceramic bearings to be used. This is only a prototype, but it's working out really nicely.
sorry, kinda getting off topic here........
This wasn't really ready to show yet, but here's some rather crummy preview pics:
http://www.william-reed.net/audio/newpics/
The new ceramic yaw bearings feature a much longer brass/aluminium/carbon-fibre-damped shaft set in a split, adjustable carrier
and the pitch bearings are carried on a split, adjustable aluminium yoke. Both can be dismantled and re-assembled by anyone.
The nice thing about this is that because assembly doesn't require any machine tools, I could offer it as a kit(s), which could be:
1 - yaw bearings: the solid aluminium centre for the arm, the bearing shaft, the arm yoke, bearings
2 - pitch bearings: a modified Rega brass body, new bearing carrier, new spindle, bearings
3 - end stub and weight
Low pivot weights.
When measuring this arm, I decided that my previous ideas about low-pivot weights were seriously wrong - I was building in far too much stability which was OK when the record was completely flat but led to very low-frequency (<10Hz) resonance with warps. The new arm reverts to a centreline weight with a slight low bias, giving a just-stable result. I've tried to match the stability to the Music Maker III compliance, about .002gm/mm offset, but only listening will tell.
As you can see, most of the work's done but I'll write it up properly when it's finished.
Regards, Jeff |
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| jeff spall |
Hi Graham.
A couple of things I've found:
- Only taking the paint off a rega casting makes the thing *much* worse. That thick black stuff really helps damp it.
- Polishing the arm is pure vanity and I confess to being guilty. I suspect it actually does harm, because castings have a surface "skin" that will probably help damp the tube as will ting surface imperfections and cracks. The Michelle technique of bead blasting would restore this effect. It's a shame, but laquering the arm after polishing helps.
- I don't really think that the kind of holes are critical, but opening up the tube really does help. In theory, cutting a slot is surely mechanically bad as it seriously weakens the tube. In practice, that might not matter. The spiral holes work well for me and are really easy to do with a regular small bench drill if you mark out a strip of tape then wind it round.
- the very best thing I've ever done to a Rega arm tube is to put in three little disks across it at intervals down the length. This is the most effective way to damp the thing that I know.
regards, Jeff |
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| graeme uk |
thanks jeff, i would be very interested if you offered your latest bearing mods in kit form.
I like the arm, but its got weaknesses, serious ones too if putting plastic clips on it makes it loads better in the treble!!
I assume the discs cant be added without taking apart the bearings? (sorry, ive forgotten your diagrams, ill have another look in a bit.)
It will be good to know how the new bearings work out sound wise, ill keep an eye on your site. |
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| jeff spall |
"I assume the discs cant be added without taking apart the bearings?"
Hi, I'd never really thought about it, but I thing they can, but not whilst the arm is wired. Once the stub of an RB250 is off, you look straight down the tube with nothing in the way.
There's no reason you couldn't drill the arm with the bearings in place, too, although I think you want to keep the bearings clean by maybe stuffing the stub end of the arm with cotton wool before you start.
I'll try to look out my last lot of measurements for the disks, but each arm varies a little.
Whereabouts in Essex are you, if you're near to the M25, I'm just off junction 5 and you'd be welcome to use my (rather crappy) home workshop.
Regards, Jeff |
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| graeme uk |
Thanks for that, the dimensions of the discs would be great.
At the moment everything i do will be with the bearings in place as i dont want to get into that yet.
I was down your way last week (went to sevenoaks) but unfortunately im now in sheffield, but thanks for the very genorous offer.
I still get down that way quite often as my parents live in romford so may one day swing by for a chat if thats ok.
For now ill fit an aftermarket sub and weight (probably michells) and drill the tube.
If i can get some made, or manage it with my limited tools, ill add the discs too and rewire while im at it.
That should keep me busy for a bit:D
Actually, on the subject of end stubs and weights, sou say you didnt like the low slung weight.
Michells weight is low slung, do you think the Origin Live set up is better? |
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| jeff spall |
The whole point of low-slung weights is that they add stability to the arm in the vertical and horizontal planes (which is why they appear on every unipivot). It will tend to return to it's original position when deflected because of the geometry change and therefore "weight" change as the arm rotates. the Michell weight cleverly keeps this effect to a minimum by making the cross section small - it's a cylinder. The one i made had a very large stability effect because it put a lot of mass way below the centreline - I know now that it was a bad move because although the sound was greatly improved on flat discs, it excited almost-subsonic noise from the very compliant cartridge on warped discs. Less compliant cartridges (like MCs) can take a more stable arm and I think the Michell would be ideal.
regards, jeff |
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| Gforce |
Jeff
it looks very interesting. I found your site last year and was very interested in what you have done to the RB250... especially the VTA adjustment!
I would be very interested in the your bearing mod kit if you ever offer it.
Would you still use the Rega anti-skate, or move over to the thread and weight system?
I did rewire my Rega with Satcure, nearly drilled it... but didn't.
I think I might try this as well as your disc idea. I think it is possible to do this without removing the bearings as you've pointed out.
The discs might be harder to machine...I don't have a lathe, which I think would be a great help in machining them.
Any way very much appreciate you sharing with us.
Regards
Gerry |
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| jeff spall |
Hi Gerry,
Those disks are something that you could make with just a drill - it's just an awful lot easier with a lathe.
Assuming no lathe, no way to cut threads and no micrometer, start with a length of M3 threaded rod and some nuts.
Cut out and drill some 1/2 - 1mm thick aluminium to roughly the right shape - cut 6 or 8 of them.
Mount one on a bit of the rod in the drill and use files to round it to a little oversize. You can now use that as a guage to see where it fits down the tube. Get it to size for the smallest fit - at the cartridge end. This will need lots of test fits! You'll want to be able to push it to within about 5mm of the finished place. Now mount the rest of your disks on the rod with your trial disk and use that as a guage to size the others - give the whole lot a slight taper. If you make lots of disks and want two or three, you'll find the ones that fit where you want them.The size difference is very subtle A slight burr left on the edge will help when fitting.
You then use your rod with just one nut on to insert the disks onto the arm. Once they are pushed home, give the end a tap with a hammer - this is where the extra 5mm movement comes in. Job done!
The very best way is to heat the arm tube as well, but you can only do that with a bare, stripped tube. |
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| Gforce |
Jeff, thanks. Very helpful. I will give it a go.
Regards
Gerry |
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| AudioOrigami |
| quote: | [i]
Replacement bearings are about £4 each from RS components and all 4 are the same. do resist the temptation to try high-precision bearings in standard Rega mounts as the location isn't accurate enough for them and the results will be far worse than ABEC3 bearings. The RS ones are ABEC5 which is a bit tighet for this application, so running them in well before installing them is well worth the effort. [/B] |
hi
yes i cant aggree more on this subject...i get a lot of enquires about new bearings on a rega
nice work on the modified bearing area m8ty
best wishes
j7:smash: |
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| Derekva |
Just to clarify...you can disassemble an RB300 to rewire? I'm planning on rewiring an RB300 in the not-too-distant future and don't want to ruin the arm.
Thanks!
-Derek |
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| jeff spall |
Hi, yes you can with an RB300 because the yoke only has one side, but if you are starting with an arm that's wired you simply use one of the existing wires to pull through the new ones, so there's no need to take the arm apart. Unless I really had to I wouldn't disturb the factory setup of the bearings.
regard, jeff |
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| serse |
Hi Jeff,
Just a quickie : how do you remove the black paint on the arm tube ?
Thanks
Pascal |
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| jeff spall |
Hi, providing the arm is completely bare - like no wires or bearings - ordinary piant stripper works very quickly. I used "Nitromors" brand.
I would say that just taking the paint off an otherwise unmodified arm tube actually makes it rather worse than standard!
regards, Jeff |
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| AudioOrigami |
| quote: | Originally posted by jeff spall
Hi, providing the arm is completely bare - like no wires or bearings - ordinary piant stripper works very quickly. I used "Nitromors" brand.
I would say that just taking the paint off an otherwise unmodified arm tube actually makes it rather worse than standard!
regards, Jeff |
yip and under the paint the casting marks can be seen...the thick black paint rega use hides the true alloy surface
so be prepared to spend some time finishing the bare alloy
hope that helps
best wishes
j7
:smash: |
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| jeff spall |
| Hi, if you have a little bench grinder, invest in a polishing kit - 6-inch graded mops that replace one of the grinding wheels. A good quallity set will cost about 45 Euro on ebay and you'll wonder how you ever managed without it. Arm comes up real shiney in just a few minutes, like: |
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| serse |
| quote: | Originally posted by jeff spall
I would say that just taking the paint off an otherwise unmodified arm tube actually makes it rather worse than standard!
regards, Jeff |
...so the need to drill the armtube I guess ? And what's about drilling without taking the paint off ? I mean is it just for aesthetics consideration or is there any function rational behind it ?
Pascal |
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| jeff spall |
Hi, it's just very hard to do all that stuff to an arm tube without scratching it, hence stripping the paint off!
I guess polishing is just vanity, and painting it again afterwards might be a better idea! I give mine a light coat of clear varnish, but that's just to keep them shiny.
Drilling holes is a very important part of the mods, both for resonance control and to reduce effective mass, Michell and OL have both recently started doing this to their Rega arms. i don't know if there's a best pattern for holes, but any reasonable shape seems to make a big difference.
Jeff |
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| Algar_emi |
I rewired my RB300 in just 1 hour, without disassembling anything. Mine came from audiogon without wires in it, so I had to re-run a small wire first to pull the new wires.
I used a small wirewrap wire that I ran first into the arm going from the bottom of the toenarm pilar, then through the small hole under the tube (between the axis, the touchy part), then up to the exit at the headshell end.
The new wires were soldered together, then I solder it to the pull wire.
Then I simply pull all the wires back from the pilar entry up to the end of the tonearm tube.
It was easy. Bearing removal is certainly not recommended since you don't have the proper tool to readjust the bearing, etc...
Bye. |
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| promitheus |
what kind of metal is the rega arm made of?
can you solder it?
The reason I am asking is because I want to ground the arm.
I dont have the plastic cap cover that covers the hole at the opening of the arm and I cant hold a wire in place there.
Any ideas? |
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| jeff spall |
Hi, it's said to be an aluminium/magnesium alloy.
Carr's do solders that will work with aluminium:
http://www.chronos.ltd.uk
What I have done is to drill a 0.9 - 1mm hole underneath the arm and tightly press in a small piece of copper wire. You can then easily solder the ground wire to that, running it into the arm through another hole nearby.
The ground wire is really important, as I found when one broke - there was a very noticable
hum!
regards, Jeff |
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| spikeyfaz |
I've been trying to contact Jeff re his offer to supply his revised RB250 bearing kits but I've had no replies to my emails :bawling: . Anyone know how else to contact him?
Jeff: if you're out there, please get in touch :cheers: . |
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| serse |
| quote: | Originally posted by jeff spall
Hi, it's just very hard to do all that stuff to an arm tube without scratching it, hence stripping the paint off!
Jeff |
Well, I managed to make it last night. Not that difficult with a Dremel and a masking tape.
BTW, what kind of foam do you put into the arm tube ?
Pascal |
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| jeff spall |
Hi, sorry,
I've been away for the last couple of weeks, and I think there has been a problem with the "william-reed.net" email address - I don't have any emails in the "in" box, but I think it's working now. If not, try "jeff.spall@william-reed.co.uk" instead - I know that's OK.
The kits are progressing slowly, I'm working through a set of ten and so far have the materials, the bearings and a set of arm yokes and I'm gradually building jigs to make the parts. It actually takes far longer to make jigs than to make the parts, but when you're making more than one of anything, it has to be repeatable.
I had just realised that, although I've been using Rega arm tubes, my bearing assembly would work with any home-grown arm tube.
Well done with the drilling Pascal, you mst be more careful at this stuff that I am! I've not filled an arm with foam, although I'd always intended to. The main reason is because I'm still experimenting and once an arm is foam filled, you can't get the wiring out again!
regards, Jeff |
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| serse |
| quote: | Originally posted by jeff spall
Well done with the drilling Pascal, you mst be more careful at this stuff that I am! I've not filled an arm with foam, although I'd always intended to. The main reason is because I'm still experimenting and once an arm is foam filled, you can't get the wiring out again!
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The tip is to use first a fine drill then to use the hole as a guide for the final drilling
Concerning the foam, I intended to do something "à la Michell". But the problem is that I have already rewired the arm... So unless I can manage to insert some foam into the holes, I fear it's too late...
Please let me know about your offer concerning the bearings. I may be interested.
All the best
Pascal |
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| spikeyfaz |
| quote: | Originally posted by jeff spall
I had just realised that, although I've been using Rega arm tubes, my bearing assembly would work with any home-grown arm tube.
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This is of great interest to me. I only resorted to modifying the Rega when my home-brewed arm failed to perfom through lack of proper bearings. I reckon your kit would be just the job.
I'd be grateful if you could let me know when you have the kits ready to sell. I've sent you another email as well, just in case.
Regards,
Mike |
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| koyaanisqatsi |
hi jeff,
long time no see (u replied to an email of mine about bearings a couple of years ago), i checked ur site recently and didnt find these new pics. you're replacing everything but the armtube (on the rega 250) it seems. i would have thought a nice ebony armtube would finish this baby off nicely.
certainly i would be interested in your kits, except i only found this site today (late to the party as usual, but normally with the best p....), and i'm already deep into the "air bearing" arm thread and the copy shroder thread (which Frank (shroder) himself has posted on... he doesn't mind diy copies at all!) . i may just have to build all three i guess. it sure would be interesting to organise a "sound off" between the best arms on this site.
steve |
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| koyaanisqatsi |
as far as rewiring a rega, or any arm goes, i dont understand why anyone would lay out 70-100 on a wiring kit, when u can buy buy enough silver litz wire on a roll to do the job for 20 quid.... and copper litz (silver plated), which might sound better(less sharp )....for even less.
just run it down the arm and plait the wires from the arm to the amp, and finish off with a couple of bullet plugs.... 40 quid all in and better quality....
just an idea. |
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| jeff spall |
Hi Steve.
I've been rather quiet for the last few weeks as I now have a set of kits maybe more than half ready, and yes you could use them with any home-made arm tube. No photos of the "production" ones yet, but the arm I'm using now (finished, polished and laquered) is at
http://www.william-reed.net/audio/newpics/
and I'm really, really pleased with the result.
You're right about the wiring. 1/2 metre of silver Van den Hul comes to not much more that £20. The very best wire I've found is the Audio Note stuff, which is expensive at maybe £40 but really worth it.
I found a trick to soldering Audio Note wire: i was told you have to burn off the insulation with the iron, a terrible job. I now use a tiny drop of "Nitromors" paint stripper and dip the wire end in that for a moment or two, then wipe. Result, perfectly clean silver. I've also started using the Michell cartridge tags. Horribly expensive, but so much better than any others.
regards, Jeff |
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| johnm |
Hi there!
Just wanted to say your modified arm looks awsome, and I'd love to do this to my RB250.
I'd also be interested in buying one of these kits to while away those winter months!
Cheers,
- John |
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| tubenut |
| Anyone know why Origin Live say the drilling/milling holes/slots in the arm tube can only be done on the RB250? |
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| AudioOrigami |
| might be because the bearing area in a rb300 iss much harder to strip out before any drilling work can be done;) |
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| woodturner-fran |
Hi all,
I've rewired a RB300 with cardas 33awg. Its been a labour of love but its done now.
My question is to do with anti-skate. When I balance out the arm with the cart on, arm floating, the arm swings back towards the arm rest - obviously the tension of the wires in the arm post is causing this. If I fiddle with the block in the arm post I can adjust where the arm comes to rest, but I can't seem to stop this tendancy to swing.
Anyone have any tips to stop this happening?
BTW: the rubber grommits are still in, I have an extra bit of wire left in the arm post to try and lessen the "swing".
Fran |
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| AudioOrigami |
on most regas...the anti skat magnet is still engaged even when the scale is set to zero...
so it may not all be down to the wires pulling the arm back
best wishes
j7 |
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| woodturner-fran |
Many thanks for that tip J7.
(actually you don't know how long I agonised over whether to send the arm to you or do it myself. In the end I did it myself but am constantaly doubting it! Moral of the story - shouldn't be a cheapskate/pigheaded - send it to j7))
When the arm floats, it swings back fairly gently, but the strength of the swing is higher towards the centre. As a result I have my antiskate set fairly low - <1 for a 2g VTA. It just passes the 3rd track on the HFNRR test record at that. One channel is a bit louder than the other, but I think that might be azimuth.
Thanks again,
Fran |
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| AudioOrigami |
you can use a thin wedge like paper under 1 of the cart bolts if the azimith is slightly out
i use a cartridge with a flip down stylis guard to check if the bottom of the stylis guard is flat all along the record surface:)
dl110 works well for this:D |
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| Panelhead |
Now I see where my unused ceramic flanged bearings will not improve my RB-250. That is 100.00 down the drain.
Also, I have some very good quality "sticky tape" to damp the arm tube. A pain to apply, but works great. It is a high temp, high strength material. HTis does make a large improvement.
George |
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| tubenut |
Seeing as this is turning in to a bit of an RB300/250 general mod thread......
I have been fitting RB300 stubs and weights to RB250 arms for people for a while now and for a lot less then the OL mod it is a big step up.
Anyways, reading the gumph on OL, Expressimo, Clearaudio Turbo weight, Michel Techno etc etc there is some conflicting stuff or perhaps there is more then one aspect that improves things that differnt weights may address differently.
The OL and Expressimo make a big deal out of tightly coupling the stub. The expressimo does this by just providing a hex cut out for a hex key. Nothing a set of pliers and massking tape on the stub (just to avoid scratches) could not achieve. (ALWAYS REMOVE ARM FROM MOUNTING BOARD/DECK WHEN TORQUEING UP A STUB AND ONLY HOLD THE ARM TUBE, NOT THE ARM PILLAR AS YOU COULD DAMAGE BEARINGS)
The thread in the arms is very coarse, certainly not precision machined.... So this evening I removed the stub from one of my RB300 arms fitted with tungsten weight and wrapped some PTFE plumbing tape on to the stub thread and put it back. It all felt a lot more snug going in and the sound definately appears to have better flow and be less ragged.
While the stub was off I had another look at the actual end of the tube and is not very precisely cut or machined, the paint covers this partly.
On most of these arms if one looks at the seam between stub and arm tube there always seems to be some gaping due to the "rough" tube end.
I am considering to take the stub out and use very fine grit sand paper placed on a flat surface to rub the arm tube end on. The idea is to get rid of the paint and burs/rough edges where the stub flange mates with the arm tube.
Perhaps a fibre/paper washer could help there as well.
A paper doughnut works wonders between sub platter and outer platter on a Linn.....
Any thoughts anyone? |
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| Aleksunder |
| quote: | Originally posted by tubenut
Seeing as this is turning in to a bit of an RB300/250 general mod thread......
I have been fitting RB300 stubs and weights to RB250 arms for people for a while now and for a lot less then the OL mod it is a big step up.
Anyways, reading the gumph on OL, Expressimo, Clearaudio Turbo weight, Michel Techno etc etc there is some conflicting stuff or perhaps there is more then one aspect that improves things that differnt weights may address differently. |
That's always driven me nuts; "for every expert there's an equal and opposite expert"
| quote: | Originally posted by tubenut
The OL and Expressimo make a big deal out of tightly coupling the stub. The expressimo does this by just providing a hex cut out for a hex key. Nothing a set of pliers and massking tape on the stub (just to avoid scratches) could not achieve. (ALWAYS REMOVE ARM FROM MOUNTING BOARD/DECK WHEN TORQUEING UP A STUB AND ONLY HOLD THE ARM TUBE, NOT THE ARM PILLAR AS YOU COULD DAMAGE BEARINGS) |
I have a Expressimo '2-xtreme' which uses an insert and through-bolt like the OL - this arrangement definitely allows much more pressure to be applied at the stub/arm tube interface.
| quote: | Originally posted by tubenut
The thread in the arms is very coarse, certainly not precision machined.... |
Which is another reason for using the insert and through-bolt a la OL, I reckon.
| quote: | Originally posted by tubenut
So this evening I removed the stub from one of my RB300 arms fitted with tungsten weight and wrapped some PTFE plumbing tape on to the stub thread and put it back. It all felt a lot more snug going in and the sound definately appears to have better flow and be less ragged.
While the stub was off I had another look at the actual end of the tube and is not very precisely cut or machined, the paint covers this partly.
On most of these arms if one looks at the seam between stub and arm tube there always seems to be some gaping due to the "rough" tube end.
I am considering to take the stub out and use very fine grit sand paper placed on a flat surface to rub the arm tube end on. The idea is to get rid of the paint and burs/rough edges where the stub flange mates with the arm tube.
Perhaps a fibre/paper washer could help there as well.
A paper doughnut works wonders between sub platter and outer platter on a Linn.....
Any thoughts anyone? |
I did exactly what you're suggesting - flattened off the end of the arm tube with some emery wrapped around a small piece of glass - you need to take lot of care to keep it absolutely square..
Using PTFE tape on a standard RB300 stub sounds like a good idea - it might allow more torque to be applied without risking damage to the alloy thread, and conversely might also make it easier to loosen again if needed. |
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| Aleksunder |
| quote: | Originally posted by tubenut
The OL and Expressimo make a big deal out of tightly coupling the stub. The expressimo does this by just providing a hex cut out for a hex key. Nothing a set of pliers and massking tape on the stub (just to avoid scratches) could not achieve. (ALWAYS REMOVE ARM FROM MOUNTING BOARD/DECK WHEN TORQUEING UP A STUB AND ONLY HOLD THE ARM TUBE, NOT THE ARM PILLAR AS YOU COULD DAMAGE BEARINGS)
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Another observation about the insert and through-bolt stub (OL);
in tightening the bolt, you only need to hold the stub itself, which being made of steel is a lot less hassle to clamp adequately than the arm-tube, and there is also no risk at all of damaging the bearings.
Still needs to be done with the arm off the TT, of course.
As an aside, I can't understand why the OL stub doesn't use the same 1/2" diameter as the standard one, hence (I assume) you can't use a Rega weight with it (although obviously this would be moot with the RB250).
Given that the price of the OL (nearly £80 all-in) is major dis-incentive for many people, it would have been nice if the stub had been designed to compatible with Rega weights and sold on it's own . |
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| alspe |
Hi.
My mother language isn't english so I ask 'cos reading all takes so much time. :-(
I have Rega Planar 2 and RB250. (Denon DL110 cart)
Is there DIN-plug inside pivot/tone arm? Can I change ext cabling just with 5-pin DIN -> 2xRCA-cable? Or is wiring unbroken from cart to rca-plugs?
I' using additional extension RCA-cable with my Planar RCA-cable so that it reaches to my RIAA (RIAA is Creek phono card inside Creek amplifier, so I can not move RIAA). I would like to get rid of extension cable, it certainly would not do good for sound? :(
Is it possible to re-wire internal wire of RB250 or should I just cut original cable underneath to plinth and solder better cable in right length and better plugs. If there's not DIN plug?
What would be good cable? Cardas has AWG33 tonearm cable for ext re-wire. LINK
Would ordinary Tasker C850/C208 etc be good if I change just external cable by cutting original cable?
So for so many questions! :bigeyes:
-Ali |
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| jeff spall |
Hi, inside the base of the arm the tonearm wires and the external interconnect are soldered to contacts on the inside of the black plastic plug that fits in the base.
If you undo the M3 screw in the bottom of the base then it is possible to pull the plug out just enough to get to the solder contacts. You can then unsolder the plug to change the wiring. If you just cut the interconnect wires coming out of the base you introduce yet another solder joint.
IMO The weakest part of the Rega wiring is the internal wires:
The cartridge tags are soldered to a short length of wire which is then soldered to the tonearm wire at the headshell end. The other end of the tonearm wire is then soldered to the contacts of the plug with the interconnect wire.
The earth (ground) wire is soldered to one of the signal earths (returns) inside the plug. Not good. The first thing to do if changing the wiring is to separate the grounding wire from the signal by providing a separate earth wire.
If you do start taking the arm apart to change the wire, it is very important that the tonearm wire inside the base is dressed properly or it can upset the tracking of the arm. It is much harder than you think to do this properly, especially first time and the performance of the arm depends on those wires sitting nicely inside the base.
The easiest alternative is to use a ready-prepared kit like the Incognito one. Most of the work is already done for you, but they are expensive.
My own choice is to get rid of the plug all together, rewire the arm with good quality tags and internal wire and then terminate that to a block fixed to the underside of the armboard or plinth with phono/DIN sockets, like this:
http://www.audiomods.co.uk/images/kondo2.jpg
The arm needs careful handling when it's not mounted on the turntable, but the performance is much improved. |
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| alspe |
| quote: | Originally posted by jeff spall
Hi, inside the base of the arm the tonearm wires and the external interconnect are soldered to contacts on the inside of the black plastic plug that fits in the base.
If you undo the M3 screw in the bottom of the base then it is possible to pull the plug out just enough to get to the solder contacts. You can then unsolder the plug to change the wiring. If you just cut the interconnect wires coming out of the base you introduce yet another solder joint.
IMO The weakest part of the Rega wiring is the internal wires:
The cartridge tags are soldered to a short length of wire which is then soldered to the tonearm wire at the headshell end. The other end of the tonearm wire is then soldered to the contacts of the plug with the interconnect wire.
The easiest alternative is to use a ready-prepared kit like the Incognito one. Most of the work is already done for you, but they are expensive.
My own choice is to get rid of the plug all together, rewire the arm with good quality tags and internal wire and then terminate that to a block fixed to the underside of the armboard or plinth with phono/DIN sockets, like this:
http://www.audiomods.co.uk/images/kondo2.jpg
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Thanks for advice.
I will look for it and consider if I get to work. I think Incognito is too expensive, preferably I put that amount money to change whole turntable for better one. :)
There's couple solder joints so I think that even if I just cut external wire outside plinth and solder nice piece of good screened cables, it can't be worse situation than now. Because now there's original cable and extension of like same cable. Like two of these together.
 :smash: |
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