New epoxy bonded Bearing Base Plate

[Mike_New]

Hi Folks,
After numerous emails requesting advice on VTA height and clearance problems when transplanting new Tone Arms onto the SL1200 I have evolved a new method of attaching the Base Plate to the Chassis.

This new method does not require the dismantling of the SL1200, other than removing the circuit board.

This Base Plate can be simply bonded to the bottom of the Chassis using the new, High Strength, two-Part Alraldite Epoxy now available. This now allows those whose DIY skills are somewhat limited to enjoy the advantages of having a Bearing Base Plate installed. The bottom of the Base Plate is acid etched for maximum bond strength. The total bonded surface area of the Base Plate is Approx 15 1/2 Sq Inch; providing an extremely rigid connection to the Alluminium Chassis when using this Epoxy; which I am told is the consumer packaged version of the Industrial grade.

In fact I can now offer the Base Plate in two thickness’s. Also using the new ETP platter I can now provide this in much higher profiles with a deeper skirt on the underside, which will not show up the edge between platter and chassis when the Base Plate is used.
However the Base Plate would have to be supplied with the platter as a set if the thicker Base Plate were required.

In this way it is now possible to mount the Tone Arm of your choice at close to chassis height using a much thicker arm board of your choice, Wood, Ebony, Alluminium or ETP compound. This removes the problem of Arm rests etc which seem to get in the way with the arm well and is always a compromise.

[Marco]

Hi Mike,

Some pictures would be good, mate, showing the new products... Also, I'll move this to the trade area for you, as that's where something of this nature should be :)

Marco.

[Mike_New]

Thanks Marco,
Ron I believe is the first person in the UK to fit one.
He might have some comments from a user's point of view.

[Marco]

Nice one, Mike. Remind us of the price again of this mod? Meanwhile, here are some pictures, detailing Ron's step-by-step installation of the New epoxy bonded Bearing Base Plate:


http://img51.imageshack.us/img51/309/p1000104rl.jpg (http://imageshack.us/photo/my-images/51/p1000104rl.jpg/) http://img406.imageshack.us/img406/743/p1000111ku.jpg (http://imageshack.us/photo/my-images/406/p1000111ku.jpg/)


http://img141.imageshack.us/img141/9457/p1000112b.jpg (http://imageshack.us/photo/my-images/141/p1000112b.jpg/) http://img252.imageshack.us/img252/8254/p1000115t.jpg (http://imageshack.us/photo/my-images/252/p1000115t.jpg/)


http://img513.imageshack.us/img513/9663/p1000123e.jpg (http://imageshack.us/photo/my-images/513/p1000123e.jpg/) http://img833.imageshack.us/img833/4467/p1000124s.jpg (http://imageshack.us/photo/my-images/833/p1000124s.jpg/)


http://img580.imageshack.us/img580/1271/p1000125h.jpg (http://imageshack.us/photo/my-images/580/p1000125h.jpg/) http://img403.imageshack.us/img403/7518/p1000126e.jpg (http://imageshack.us/photo/my-images/403/p1000126e.jpg/)


http://img405.imageshack.us/img405/7839/p1000131qp.jpg (http://imageshack.us/photo/my-images/405/p1000131qp.jpg/) http://img21.imageshack.us/img21/5815/p1000136ad.jpg (http://imageshack.us/photo/my-images/21/p1000136ad.jpg/)


That should give folks a good idea of what's involved in fitting it! :cool:

Marco.

[Mike_New]

Hi Marco,
I think I must have given you a bum steer.
The person I was thinking of has a Base Plate but without the five bolts.
I am trying to recall his name on my email database.
The idea is that the base Plate is bonded directly to the bottom of the Alluminium chassis
without using any bolts. This way we avoid the need to dismantle the whole SL1200 into it's three sections.

[Marco]

Ah, ok - not to worry... When you remember who it is, let me know. In any case, when I get a bearing base plate, the above is how I'd like the job done! :)

Remind us of the price again, Mike?

Marco.

[Mike_New]

The cost of the Bearing Base Plate is A$235.00 =157.00 BPs
The bottom is acid etched to improve adhesion.
I reckon you should even be able to install it Marco.

[JazzBones]

A belated hi Mike and Marco, and many thanks for posting the photos for me (a better job than I would've done ;))

Mike: I think you meant I was the first person in the UK to drill three additional tapped screws holes into the MN bearing flange itself making a total of six screws to secure the bearing... 3 for the flange, base to top... see filed down ends, and then the filed down and reamed three holes from top into the three point bearing fixing. Its not a hard job but requires a simple jig to hold the bearing spindle facing down to enable dead accurate drilling and then tapping to take place. The prob is that you have to be dead accurate first time round :) but Mike had already pre-drilled the based plate, counter sunk, before despatch so this was used as the temp plate. You will also notice that I used a damping ring on the bearing barrel (not really necessary) but it adds a little more damping. Once the bearing is secured to the base plate as per new drilled holds I used Holymar Blue automotive gasketing paste to secure (breakable if required and allowing removal) to mate the base plate to the Techy pan and secured it with the five bolts, the holes having been drilled first, I exchanged the nuts Mike provided for flanged self locking nuts so all in all, and IMO, this is the most secure fitting for Mike's bearing I know of?

You will also notice, from the photos, that I used very thin self adhesive damping sheets (from Russ Andrews Accessories) to dampen the outside of the Techi pan.

Not shown, is an additional centre footer, under the bearing housing, to further support the deck, I mentioned this to Mike and he replied that it was a worthwhile mod.... I don't know how this would work out with Isonoe feet (?) but Mike and I both use a Seismic sink TT support in preference to the Isonoes.... Someone on A0S sold his Isonoes and uses yellow dot squash balls, get the idea :)

After everything was put back together and up and playing I was very impressed and very, very pleased with the result, yeah :) Clarity, bounce, musicality and all the PRAT a bod could ask for, yeah again.

The final task I did was to drink that bloody bottle of vino, I deserved it :lol:

Cheers

Ron :cocktail:

[Mike_New]

Thanks Ron,
You are absolutely correct in what you say it all comes back to me now.
I must locate the other fellow who wanted a Base Plate but did not want to dismantle his SL1200 in order to fit it. It is difficult to keep track of all the people who have use some or all of my upgrades over the years.

For those that are interested, the Base Plate is exactly the same as the one shown except that is does not have the five holes for the bolts.

[Marco]

Hi Ron,


A belated hi Mike and Marco, and many thanks for posting the photos for me (a better job than I would've done ;))


No worries, dude - yer welcome! Fancy fitting my base plate, when I get one? I really like how you've done it. There'll be a couple of bottles of nice vino in it for you - be a good excuse to have a listening sesh, too! :cheers:

Marco.

[JazzBones]

Hi Ron,



No worries, dude - yer welcome! Fancy fitting my base plate, when I get one? I really like how you've done it. There'll be a couple of bottles of nice vino in it for you - be a good excuse to have a listening sesh, too! :cheers:

Marco.

Marco, when I did mine I was stepping into the unknown and took more than a couple of days to finish the job... I don't mind (in a way) making a possible mistake on mine but to touch your hallowed, and god amongst Techies, would make me extremely nervous. The removal of all that circuitry for the 'Big Beastie SR7 psu' would bring on a nervous twitch.... However, I have been thinking on your Tech setup and as you now use the Funk platter, which as you know, is considerably lighter than the MN ali/copper platter that I use (and its your EX :)) I think you can achieve a similar solid foundation for your MN bearing by just having Mike's Araldited version sans the five bolt holes. MartinT already pioneered this setup with his deck...Where the MN bearing uses the existing three point fiting to the chassis, Mike drills the appropiate threaded securing bolt holes and of course provides new high tensile bolts which thread through the base plate into the Techy existing holes thus providing extra security of fixing. More importantly, you can remove the bearing itself, from the top of the plate, if need be, as Martin can. Via my method of six bolts, three through the top, three upwards from bearing base plate into the bronze bearing flange if I/you were to Araldite this/my, as per photos method, instead of a breakable gasket compound or silicon (non acidic..will corrode ferrous metal) AND PLEASE, PLEASE DON'T DO THIS OR YOU WILL NO LONGER HAVE A BEARING THAT CAN COME OUT AS IT WILL BE PERMENTLY SECURED TO THE ARALDITED BASE PLATE :eek::doh:!!! . I have chosen automotive, breakable, gasketing compound to augment the bolts thus allowing me removal of bearing plus base plate if need be.

Have a word with Martin and I'm sure he will talk you through or assist with the actual fitting. I can willingly talk you, or the person doing the job, through but believe me its all plain common sense and not open heart surgery (I've had the latter so I know what I'm talking about :))

One thing that is VERY IMPORTANT is have Mike recess the edge of the underside of the base plate if it is likely to foul the embossed raise lettering on the chassis pan, Mike is now aware of this potential prob. The base plate itself will not sit true and therefore the job cannot be done to a correct conclusion!

By the way, Mike provides a detailed instruction sheet indicating how the job is done and the sequence required. All you have to do, like I did, is hold your nerve... have fun.

It costs Mike about AUD$30.00c to mail that plate, and all necessary bolts plus brass raisers (3) to lift the PCB board and is covered by the cost of the base plate itself... you'll hear it arriving through the letter box and I assure you the dog will have a hard time chewing through it!

Don't forget that your platter will be raised approx 6mm higher.

Finally, make sure you have a variable speed drill and NEW drill bits (for mild steel) .. the Techy chassis is cast ali and will drill as easily as hard wood, wood drill bits are a no, no.

Cheers
Ron