Another DIY turntable and tonarm project journey

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Hi all, long time reader of this forum, but now I post my DIY project. The turntable project began last winter and the linked photo journey shows its progress. The most recent project just finished is a DIY tonearm. I got lots of ideas for both from places as this. I hope you all enjoy the photo essay.



Here is an added journey report of the tonearm...


Well am just finalizing my latest DIY project. I decided recently to build a DIY tonearm to add to my existing DIY turntable. In doing so I built a new armboard for the tonearm.

After much reading on DIY projects and lots of prep work, trial mock ups and modifictions. I now have a working setup.

I introduce the new "Aurel Seduction" turntable with "Equinox Series One" tonearm.

The arm is based on a uni-pivot design of my own thoughts using info gained by looking at other uni-pivots. The arm tube is 3/8ths. inch aluminum that has been painted in multiple layers (8 total) of high quality silver colour aluminum wheel paint. Not only does it improve the look of the arm wand but adds good damping to it.

The uni-pivot housing is stacked layers of cut and sanded into a square block Corian, Painted silver too. The pivot is the tip of a good quality ball point pen affixed to a 5/16ths. aluminum shaft. The shaft is sleeved into the black armboard for VTA adjustibility. The ball point pen tip sits facing up into a drilled out and lightly polished aluminimu rod captured inside the Corian block. The arm pivot rod is designed to be able to work in all six directions, up down, left, right, and roll left and right. It can be lifted off as only the weight of the Corian (which is pretty heavy relative to its size) holds it in place. I have brass rods out each side of the block in line with the pivot point. There are brass nuts as outriggers to help keep rolling forces to a minimum.

The arm tube is affixed to an aluminum rod and that is secured to the Corian block by a solid set screw. The counter-weight rod is a 3/8ths. threaded rod with a layer of shrink tube affixed to its threads where it turns into the Corian block for support. The counter-weight is a series of 3/8th dia. opening fender washers epoxied together and sunk to hang below the rod. They are held in place by being pinched with threaded nuts. This allows me to make minor azimuth adjustments so the that cartridge rides parallel to the record.

My anti-skate is a fishing line and ball weight hanging on a rod and can be adjusted along that rod.

My cueing setup (is still a work in progress) but it's a home made design to pivot the arm up and down. It's a little too light and needs some work so that mass can more easily lower it to a record. It's damped with Vaseline but not as much as I like. As I said it remains a work in progress. (I recently added a lead weight to the cueing setup and the setup works better now.)

The head shell was cut out of 1/4 inch masonite board and sanded down to the profile you see now. It's quite stiff but very light. It was painted flat back for contrast.

The arm board sits above a Silestone plinth, it is three point mounted securely to the Silestone using 3/8ths x 2.5 inch long screws. I have rubber flat washers sandwiched between the flat black armboard and Silestone base plinth. The arm board is a multi-layer MDF, HDF design cut to shape and for asthetics. Each layer was glue together with wood glue and clamped tightly to dry. It carries good mass and the top layer came plastic laminated so it looks quite nice with the flat black finish.

The platter is a sandwich of an MDF sub donut drilled out an filled with 100 round lead type fishing weight. This sits on top my layered MDF sub drive platter. The platter attached to this donut is a 12 inch round Corian platter. The combined weight is over 10 lbs and the whole set up is quite resonant dead. It all sits on a built in sand box to my top shelf of the stand.

How does it sound? Pretty good so far. I still am tweaking it. But is it better than my stock Rega RB250 arm? Hard to say, I require time to listen and get use to it. It cost me a little over $40.00 for all parts, paint n' stuff. But some things I bought were not needed or used and thusly could probably have been anywhere from $5-10 cheaper. So in my case does a $40 dollar arm give the RB250 a run? Well lets say for sound quality so far I am not disappointed. Uni-pivots are more fussy in setup but can work quite well based on their simple design concept.

This project has taken me more time than I thought because of my tinkering and modifications as I was building it. I tried different ideas before I settled on what you all see here in the photo essay.

Am I going to keep it long term over my RB250? Not sure. I'm proud of my work and that it seems to operate well but it is something I'm going to live with for a while to see how it grows on me.

It has been interesting, fun at times, and bothersome at others as I tried to design and build it out properly. Love it or leave it long term, well no matter what it works well with more tweaks needed esp. the cuing setup and I learned more about tonearms as a result. It looks quite commercial and not too DIY, which is what I wanted and needed for me to be happier with it, I'm kinda fussy that way. I'll keep it running for a good while and keep my RB250 in storage just in case my thrill over the DIY arm falls off.


LINK TO PHOTOS
 
Congratulations Phileas!

A very nice looking table and all. I must say I kinda liked the first armboard (well, maybe not the color;)) but the newer one does look more -factory-.

Some better close-ups of the pivot end of the tonearm would be interesting to see.

Also, some detail on the motor controller and mounting arrangement would be welcome. Whatare you using for a drive belt?

BTW: the last photos of the table show a much deeper platter with no evidence of the 1/2in nuts for ballast. Did you keep them or mass-up the platter with the lead weights you mention in the text?

Well done :D

Jess
 
Hi Jesse,

The first version of the turntable was interesting and the armboard was cool but it was too difficult to set up VTA on. The latest version (flat black) was cut with the curves similar to the original red board but with my uni-pivot arm I can adjust VTA by releasing two set screws on back and just slide up or down the post holding the pivot and then relock the screws. The flat black is more satin finish and looks cool on top the Black Silestone base.

The platter has changed from the first one. Instead of a 1/2in thick x 12in. dia Corian platter with an assortmnet of hex nuts hanging on the bottom as weights, then platter now is the 1/2in thick x 12in dia. Corian platter with another disc attached to it. This lower disc is a donut to fit overtop the 7 in dia x 2.25 inch thick drive platter made from MDF. This donut was also made from 1/2in thick MDF. I drew out in equal pie segments a line grid so that I could drill out 100 holes in a more or less equal spacing to plop with glue 100 round lead type fishing weights. This donut was then glued to the Corian platter and clamped to dry. Once done it looks more beefy and weighs in about 10lbs. It's quite solid and dead to resonances. I painted it silver to contrast the black table.

I'll fire off more pictures in the next day or two to post closer details of things esp. the tonearm.
 
Hi Phileas:

All in all a great job. I hope you feel is sounds a good as it looks. :) Thanks for the additional photos.

What are you using for a motor?

I have an old B&O tt that I am planning to steal the bearing, drive hub, motor and controller from to build a low-mass table. You probably know the type: vinyl platter, rubber band suspension, cassette tape for the drive belt...

I currently use a Pioneer PL51 to which I have fitted a Syrinx arm and Pioneer M403 hi-output MC cart. It makes nice tunes.

I have two suggestions for your project:

1) you might try decoupling your counterweight from the pivot body. You could replace the threaded stud with a piece of nylon rod threaded to screw into the same hole. Or, you could bore out the hole in the counterweight itself and slip some PVC tubing over the stud. This is a common upgrade for Rega arms and makes quite a difference. Most people don't want to modify a factory arm in case they want to sell it later, but one of the joys of DIY ...

2) I really urge you to replace the wire in your tonearm with some 0.2mm copper litz wire (or similar). Its a simple upgrade and makes a world of difference. (If you cant find some, email me off line and I will send you some.)

BTW: you obviously have much better skills with painting than I do - my paint jobs usually look like they were done by a 5-year-old :xeye:

Onward and inward!

Jess
 
Hi Jesse,



The motor I have came from an older Kenwood table circa about 1990. It is made by Sankyo a Japanese electric motor co. The motor is a D.C. servo motor and the box that I built to house it and switch gear allows me to not only turn it on and off but electronically set the speed for either 33.3 or 45 ropm. There are trim pots that I can adjust with a jewelers screwdriver to set final speed using a strobe disc. The setup runs very smoothly and I cannot detect any wow and flutter to my hearing which is quite good and acute for pitch etc. I est. the factory W&F was probably around .05-.06% WRMS on a plasticky Kenwood table with thin ringy aluminum platter. My mass induce setup and platter may help speed stability a bit.

The drive is a cassette tape around an MDF sub-platter. The motor has good torque for decent start up speed.

The rod for my counter-weight has had a layer of shrink tube applied to it were it seats inside the drilled out hole in the Corian block. It was set in to be parallel to the pivot point and the weight drilled to sit slightly below the pivot point.

My tonearm wires are pretty decent. They came from what was likely a 70's vintage BSR table (looked pretty high end for its day) that I bought at a thrift store for $10.00 Cdn. I may replace it with better wires one day, but truly this arm and table sound superb. I have it dialed in quite well now and playing some familar albums I am IMPRESSED with the sound. I think it may actually sound better with the Denon DL-110 cartridge than when I had that cartridge on my Rega RB250 arm. It is so hard to tell though but the imaging is very nice, the sound stage quite wide and deep. Record noise is quite low. The arm is lower in mass compared to my RB250. I used the supplied weight plate for the DL-110 to increase its rather low-moderate mass, moderate compliance and this weight just zeroed in the sound stage.

I'll live with the arm for a while and then decide if I can tell myself to sell the RB250, but only if I can live long term with this arm.

I am good with paint, I build plastic models for a main pastime and hobby.
 
Well after more tweaking of things as TF and VTA etc. and alot of listening to some albums I know well, I am more and more impressed with the updated table I made along with the tonearm I made for it. I am honestly thinking it does with the Denon DL-110 cartridge edge out my RB250 arm. It seems to have slightly better focus on imaging esp. vocals and a wider spacial image too. I don't think it's in my head. I think it really is riding the grooves better. This being said the RB 250 performed very well too and I did not embark on a DIY arm project because I did not like my RB250. I did it to see what spending minimal money and putting my own honest effort at crafting an arm could give me. I think the quality ball point pen as a uni-pivot bearing is a superlative choice. I mean ball point pens if from a good maker are in essence as high quality ball bearing as one will likely be able to get.

As I play more an more albums I think my DIY arm on the modified turntable for it is a better performer than the RB250 was. I will easily put my DIY table and arm combo up against anything in the $1000-$1500 range. I worked hard on design and making of the table and even harder on making my tonearm. As said I figured I spent easily 50-60 hours working on the arm alone trying to get it right, making alterations as I was creating it and trying out different things in the process.

I have a modest mid-fi system with a mid-range Denon receiver a Cambridge Audio 640p phono preamp, good quality RCA's and a super pair of Paradigm Export BP (BiPolar) full range speakers which for the price in the right room setup (mine is pretty good setup for Bipolars) are giant killers IMO and I have never heard audio sound as good to me, and I sold this stuff in a shop which carried better end stuff too for a few years. I'm not saying my system is the be all and end all, but for a competent mid-fi setup and in my room with careful placement of speakers etc. its sound with esp. vinyl on my DIY setup is sweet and the best sound I have owned to date.
 
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