Subject: Re: [teres] Teres-Bearing & Platter - New Info Date: Fri, 24 Mar 2000 00:33:40 -0700 From: WMollard, WMollard To: teres@aiko.com Thanks Chris and Bryce! You guys are the best!! Even if the 3" change was an option I would continue with the 3 x 1" rather than triple the cost to provide 3" billets. Full steam ahead... geeze maybe I ought to buy a cartridge, arm, a few records and get on with building a preamp. The modified Loesch circuit looks mighty good on your web site BTW. Once again, thanks for your effort, it is greatly apreciated! Best Bill -----Original Message----- From: Chris Brady To: teres@aiko.com Date: Thursday, March 23, 2000 9:34 PM Subject: [teres] Teres-Bearing & Platter - New Info >I have new information about our options for different >platter materials. Cutting to the chase we have no other >viable options. > >As usual Bryce had already fully explored our options. Bryce had >already given 3" acrylic sheet full consideration including some >price estimates. The price for the material 3" was roughly twice >as much. But the real hitch for using the 3" material is cutting. >Few suppliers have the capability to cut this thick of material and >nobody local to Bryce can. Even though Bryce did not get an actual >quote to cut the material he was certain that the cutting cost would >be greater than the cost of the material. At this point using 3" >acrylic is simply too expensive. There is an interesting possibility >of having 3" circles cast rather than cutting them from sheet. This >is also too expensive and uncertain to consider for this order, but >it would be better than cutting from 3" sheet. For those with deep >pockets and a desire for perfect cosmetics this would be a **possible** >but expensive option for a future order. > >Bryce checked into using black acrylic and found that it was also >very expensive. The problem is that colored acrylic is not commonly >used and would be an expensive special order to get the quantity that >we need. The price would be more than double and the lead time would >be about 8 weeks. > >This is all a moot point since the platter materials have already been >ordered and we didn't really have on option of changing the material >order without paying some possibly stiff penalties. However, it is >good to know that Bryce did his homework and I certainly would not >change anything now even if we did have the option. > >Chris > Subject: Re: [teres] Bases and Vibration Date: Mon, 27 Mar 2000 00:58:59 -0700 From: PEARL Cust Serv, PEARL Cust Serv To: teres@aiko.com Jon Lane jhlane@email.msn.com wrote: >> Bill @ PEARL, Inc. wrote: >> This is old hat really . . . . vacuum >> hold-down T/Ts exist in the first >> place to deal with THIS issue probably more than >> record warp. > > A dear friend of mine and dedicated audiophile actually > bought two copies of each favorite record and marked each > one with a preferred playing side. His vacuum hold-down > platter ruined the other side. Ended up with too much noise > to bear... > > But the Oracle uses a little tapered washer under the record > which forces the rim down as the clamp is applied. > > Jon Lane ============================== Hi: At my very 1st trade show back in . . . ummm . . . . I forget :>) a busy little guy came into the room with the damnedest t/t mat. It had a HUGE hole in the center and was REALLY thin . . . I was baffled. Seeing the look on my face, he cheerfully handed me one saying, "Here ! ! ! . . . . these are for those vacuum decks so that you don't drive dirt into the grooves ! It's made out of hard, pvc gasket material with a binder of some sort." It made so much sense that I kept it around for years and years, awaiting a vacuum deck. All I can say is that this solution works, along with glove leather and a few other things . . . . Best regards, Bill - PEARL, Inc. Subject: Re(2): [teres] Oil for bearing Date: Tue, 18 Apr 2000 06:48:47 -0700 From: Pablo Roufogalis L., Pablo Roufogalis L. To: teres@aiko.com teres@aiko.com writes: > I am not aware of any viscosity being chosen as >"official", that being left still open after some >debate, and open to user experimentation. Bryce, our >machinist may have a preferance based on his >experience >and the tolerances he is machining into our bearings. >Chris, Thom, what was Bryce's recommendation? After >consideration of a few possible oils, the focus of >interest went on to other topics.... Dear Igor, Many thanks for your comments. One overkill approach (but isn't it what the high-end business is about?) would be to use the spec'ed viscosity with some sort of dry lubricant. Colloidal graphite seems right. Will do a search later for such oils and let you know. One thing that makes it right is that even if the graphite colloids break down, it will go down to the bearing, where it's most useful, directionally. We can claim it's by design ;-) Were this a commercial venture, we could repackage an industrial product and resell it at huge margins. We would have to find a catchy name for it, though. Snake Oil would be truthful but I'd guess not adequate for marketing purposes ;-) Pablo Roufogalis L. papablo@aretecnica.com (se dice papablo atencion de aretecnica punto com) ¡Arrobas NO!. Visite http://www.aretecnica.com/fam/od.htm Visite http://www.aretecnica.com/fampg.htm Subject: Re(2): [teres] Oil for bearing Date: Tue, 18 Apr 2000 10:56:27 -0700 From: Pablo Roufogalis L., Pablo Roufogalis L. To: teres@aiko.com teres@aiko.com writes: > Overkill is OK in serious audio. Do you favor >graphite over, say Teflon (and for what reasons)? I >suppose we should rule out Moly Disulphide (never >considered seriously previously on these pages) as it >is meant to settle out on the metal surfaces, and this >does not at all sound like a good idea for surfaces >machined for tolerances as tight as ours. Moly, Teflon and graphite provide friction reduction when the oil film fails to separate the metal surfaces. All three work by depositing a layer of slippery material on top of the metal surfaces so the contact is made between these layers and not between the underlying metals. I'd guess that in our application, the metal to metal contact should be negligible because of the small pressures involved. With highly polished surfaces and the spec'ed oil viscosity for the bearing clearances and overall design, there should be no significant metal to metal contact. So I'd say dry lubricants are not required. The long life of turntable bearings using regular oils back this. A molecular layer of slippery material on top of polished bearings surfaces is non-detrimental. I'd guess we could use any of the three mentioned above if we want to go the overkill route. >I have had >good results with a MS based lubricant in skate >bearings meant for high performance & frequent >replacement, but this is hardly an analogous >situation. >Your thoughts and operative guidelines? Any reason to >think that oils with additives like graphite, MS, or >Teflon, putting questions of lubrication and stability >(as isolated issues) to the side for just a moment, >may (or may not) be as (microscopically) *quiet* as >oils without any additives of a particulant nature? One test we could do, with any turntable, is to measure the drag of the bearing with and without graphite enhanced oil. The test could be to let the platter turn with a weight and a string (unattached) around the record clamp and count the number of revolutions the platter does. Do this several times to get a valid average. Then add the graphite lubricant, play several albums (black music would be adequate, say, the complete Porgy and Bess), and repeat the test several times again. Directionally, it should turn more times than before. If it doesn't we would confirm it is not needed and no harm is done. If it does, we would have advanced the state of the art ;-) The viscosity of the oils must be the same for the test. BTW, it has to be colloidal graphite. Sparkling "dry" graphite in the bearing is a bad idea. We don't want the bearing grinding a very hard material such a graphite. Regards, Pablo Roufogalis L. papablo@aretecnica.com (se dice papablo atencion de aretecnica punto com) ¡Arrobas NO!. Visite http://www.aretecnica.com/fam/od.htm Visite http://www.aretecnica.com/fampg.htm Subject: Re(3): [teres] Oil for bearing Date: Tue, 18 Apr 2000 11:36:26 -0700 From: Pablo Roufogalis L., Pablo Roufogalis L. To: teres@aiko.com Hello to all. > >To give you an idea, it is similar in viscosity to a grade 50 engine oil It's been more than ten years since I don't deal with lubricants. A grade 50 engine oil is not equivalent in viscosity to an ISO 22. ISO 22 is much lighter. Sorry. Pablo Roufogalis L. papablo@aretecnica.com (se dice papablo atencion de aretecnica punto com) ¡Arrobas NO!. Visite http://www.aretecnica.com/fam/od.htm Visite http://www.aretecnica.com/fampg.htm Subject: [teres] OIl viscosity Date: Tue, 18 Apr 2000 11:52:18 -0700 From: Pablo Roufogalis L., Pablo Roufogalis L. To: teres@aiko.com Hello again. ISO 22 is similar to 5W oil, not grade 50. Were the keys closer I could've claimed a typo :-( Regards, Pablo Roufogalis L. papablo@aretecnica.com (se dice papablo atencion de aretecnica punto com) ¡Arrobas NO!. Visite http://www.aretecnica.com/fam/od.htm Visite http://www.aretecnica.com/fampg.htm Subject: Re(2): [teres] Oil for bearing Date: Tue, 18 Apr 2000 16:13:09 -0700 From: Pablo Roufogalis L., Pablo Roufogalis L. To: teres@aiko.com teres@aiko.com writes: >I plan on such an additive, but was considering the teflon-in-mineral oil >suspension marketed in the US under the brand names "Tetra Lube", "Tetra >Bike" and "Tetra Gun". I currently use it in my Oracle bearing (as well as >on my bikes and guns and other precision bearings). Hello Steve, I'd guess any dry lubricant would be adequate. Teflon-based compounds might be easier to find as you point out. Colloidal graphite particles are very small so there won't be any grinding of large particles in the bearing. As in most things related to lubrication, a little is much better that a lot. What you get is the graphite filling in the valleys in the surface of the metal so it presents a flatter, larger and more slippery surface. Once this process is complete, no additional graphite is needed. I don't anticipate any building up of dry lubricant at any part of the bearing, even if overzealous owners "change" the oil frequently. What won't get layered in the metal surfaces will be in suspension in the oil. > > >I am not a Mechanical Engineer by any means, Me neither, it was a past incarnation ;-) >and it has been years and years >since college chemistry classes, but the use of colloidal graphite >concerns >me. I know that the use of powdered graphite in door locks, while >lubricating the mechanisms for awhile ultimately ends up gumming up the >works, and in worst cases, the graphite due to it's position on the >chemical >activity spectrum will accelerate galvanic corrosion and pitting of other >materials. Granted, our bearing surfaces will always be covered by the >base >oil, which should exclude oxygen and moisture, but I hate to take the >chance >with graphite. Never thought of galvanic corrosion in this context. I'd guess the mass ratio is so large the effect should be negligible. Teflon is of course inert so, yes, why risk it? Will look for information on Tetra products. Tetra Table sounds right. Regards and thanks for your comments. Pablo Roufogalis L. papablo@aretecnica.com (se dice papablo atencion de aretecnica punto com) ¡Arrobas NO!. Visite http://www.aretecnica.com/fam/od.htm Visite http://www.aretecnica.com/fampg.htm Subject: Re: [teres] Oil vs resistance Date: Wed, 19 Apr 2000 05:53:30 -0700 From: Pablo Roufogalis L., Pablo Roufogalis L. To: teres@aiko.com teres@aiko.com writes: >I do not remember the general conclusion of the early Teres discussion on >the desirability of using a heavy viscous oil to act as an engine brake >and >therfore improve speed regulation, like the Verdier TT. I am still in >favour >of this idea. At least in theory. Is the Verdier belt-driven? High turning resistance can cause slippage at the motor pulley which in turn can cause erratic pulling of the belt. The use of heavier oil (i.e., heavier than the one the bearing was designed to use) is an effective and simple way to add drag, if desired. I tend to believe that low turning resistance and a heavy platter is adequate for the requirements. Regards, Pablo Roufogalis L. papablo@aretecnica.com (se dice papablo atencion de aretecnica punto com) ¡Arrobas NO!. Visite http://www.aretecnica.com/fam/od.htm Visite http://www.aretecnica.com/fampg.htm Subject: Re: Re(3): [teres] Oil for bearing Date: Thu, 27 Apr 2000 21:20:39 -0700 From: Stewart Ono, Stewart Ono To: teres@aiko.com Graphite oil is favored by Linn not so much for its lubricating properties as for the fact that it is slightly conductive and will wick away the worse of the static build up. Stu Subject: [teres] RE: Teres Bearing Date: Sat, 27 May 2000 09:24:36 -0700 From: Tony Bombera, Tony Bombera To: teres@aiko.com Hi, A question to the original members of Teres group (I was likely number 8): Why do we have 2 different hardness materials: stainless steel and brass in the bearing? Would the same material work or would there be some problem? On another note, SME put a pump into their bearings. I would guess that their bearing may be similar to ours and they felt that there was a need to put the pump there. Just food for thought... Regards, Tony Bombera Subject: Re: [teres] RE: Teres Bearing Date: Sat, 27 May 2000 10:27:33 -0700 From: Chris Brady, Chris Brady To: teres@aiko.com Tony, I don't recall much discussion on the choice of materials for the bearing. It is common for bearings to use a mix of hard and soft materials. Brass is a very common material for bearings and since it is easy to machine it seemed like a good choice for the bearing body. Stainless steel was chosen because is is hard and will not rust. The idea of adding a spiral groove to pump oil to the top of the bearing was considered. But since the Teres bearing will be filled with oil a pump would not be of any benefit. However, a pump would be very useful for inverted bearings. Chris > Hi, > > A question to the original members of Teres group (I was likely number 8): > > Why do we have 2 different hardness materials: stainless steel and brass in > the bearing? > > Would the same material work or would there be some problem? > > On another note, SME put a pump into their bearings. I would guess that > their bearing may be similar to ours > and they felt that there was a need to put the pump there. Just food for > thought... > > Regards, > > Tony Bombera Subject: [teres] Platter blanks Date: Thu, 8 Jun 2000 11:04:35 -0700 From: George Powell, George Powell To: teres@aiko.com I walking along Canal Street in NYC and I found a Plastics shop. They have 12" x12" x 3" blocks for $75. If they have larger sizes would they be helpful for making the platters? They also do laser cutting for $50 ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com Subject: Re: [teres] Platter blanks Date: Thu, 8 Jun 2000 13:59:39 -0700 From: Chris Brady, Chris Brady To: teres@aiko.com George, This price is a real bargain, especially if they can laser cut the the blocks into 12.5" circles. Bryce was told that you can not do laser cutting of 3" material. If the cost for a cut 12.5" block is close to $125 then we should look into it. We could even get by with 12" material if the price is right. Chris > > I walking along Canal Street in NYC and I found a Plastics shop. They have > 12" x12" x 3" blocks for $75. If they have larger sizes would they be > helpful for making the platters? > > They also do laser cutting for $50 > ________________________________________________________________________ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com Subject: Re: [teres] Platter blanks Date: Thu, 8 Jun 2000 16:35:46 -0700 From: George Powell, George Powell To: teres@aiko.com Thom, Chris How many should say, if I need to sweeten the deal? Also I will confirm it's ingredients, the size (12.5" x 12.5" x 3") and quality of the laser cutting. >From: Chris Brady >Reply-To: teres@aiko.com >To: teres@aiko.com >Subject: Re: [teres] Platter blanks >Date: Thu, 08 Jun 2000 13:58:22 -0600 > >George, > >This price is a real bargain, especially if they can laser cut the the >blocks >into 12.5" circles. Bryce was told that you can not do laser cutting of 3" >material. If the cost for a cut 12.5" block is close to $125 then we >should >look into it. We could even get by with 12" material if the price is >right. > >Chris > > > > > I walking along Canal Street in NYC and I found a Plastics shop. They >have > > 12" x12" x 3" blocks for $75. If they have larger sizes would they be > > helpful for making the platters? > > > > They also do laser cutting for $50 > > ________________________________________________________________________ > > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com Subject: Re: [teres] Platter blanks Date: Thu, 8 Jun 2000 16:35:54 -0700 From: Thom Mackris, Thom Mackris To: teres@aiko.com The price is indeed a killer deal based on the numerous quotes we've received. My guess is that for the next go-around, we will be doing quite a bit of research on optional materials for platters (e.g. delrin) as well as sources for 3" acrylic. After all ... we're just a bunch of nutty experimenters For those who care, a 12" platter would be a reduction from the current 12.28" diameter. This would result in minor cosmetic changes at the platter's edge as well as negatively impacting compatibility with Merrill's periphery clamp. Cheers, Thom ----- Original Message ----- From: Chris Brady To: Sent: Thursday, June 08, 2000 1:58 PM Subject: Re: [teres] Platter blanks George, This price is a real bargain, especially if they can laser cut the the blocks into 12.5" circles. Bryce was told that you can not do laser cutting of 3" material. If the cost for a cut 12.5" block is close to $125 then we should look into it. We could even get by with 12" material if the price is right. Chris > > I walking along Canal Street in NYC and I found a Plastics shop. They have > 12" x12" x 3" blocks for $75. If they have larger sizes would they be > helpful for making the platters? > > They also do laser cutting for $50 > ________________________________________________________________________ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com Subject: Re: [teres] Teres Update (pictures!) Date: Tue, 20 Jun 2000 00:45:39 -0700 From: PEARL Cust Serv, PEARL Cust Serv To: teres@aiko.com; sound@lists.io.com Chris Brady wrote: >> Hmmm, I think I may do that... then again, I like the way it looks now >> anyway. What does he use for the fluid to machine the acrylic?? I need to >> get some acrylic parts machined and are not quite sure of the right method >> to do it (whether the fluid is necessary or not). >> >> Daus > Bryce found that at high speeds the acrylic chips, resulting in a white > somewhat rough finish. Too rough to be suitable for our purposes. > He tried some different speeds to get the finish in the pictures. > This seems to be a good compromise between smoothness and also >leaving a frosted finish. Bead blasting should give you the finish you are > looking for and also be quite smooth. > > Chris Hi Guys: The way to machine acrylic is with slightly negative cutting angle and about a .025" radius on the tool with about 15 deg of relief *but* with the relief taken negative by about 1-2 deg for about the first .005" to .015" down the relieved face of the tool. This way the tool scrapes rather than chips and the small amount of negative relief burnishes rather than letting the tool cut clean. By this method as-machined surfaces smooth enough to pass blood without so much as hanging up a cell can be produced. Bill - PEARL, Inc. Subject: Re: [teres] Centering pin choices Date: Sat, 24 Jun 2000 22:36:21 -0700 From: Thom Mackris / Joan Panzella, Thom Mackris / Joan Panzella To: teres@aiko.com Hi Pablo, We measured several turntables. My Merrill, Blair Hansen's Sota, Steve Z's Oracle. Our attempts at universality were to produce two removable spindles: (1) a threaded (1/4" x 20) spindle for screw-on clamps. This thread matches my Merrill and Steve's Oracle. If I recall, this is also VPI clamp compatible. (2) a smooth (unthreaded) spindle for those who either don't want to clamp or who would like to use a clamp like the Sota reflex clamp. If I recall (notes not handy, and I seem to have a preponderance for fat fingers these days ), the working diameter for the spindles is .281". This translates well from a high of .283", with most spindles measuring .281. If you convert Scheu's spindle from metric, you also arive at .281". The user of the .283" spindle (I forget who) reported numerous records which were an exceedingly tight fit. On first blush, this might appear to render a more precision fit, but when you consider that records holes are not stamped with this level of precision, we concluded that this tight a fit offers no advantage - we were in agreement with Scheu on this matter. Cheers, Thom Original Message ----- From: Pablo Roufogalis To: Sent: Saturday, June 24, 2000 5:35 PM Subject: [teres] Centering pin choices Hello to all. Looking at the updated long-playmate of the century WWW site, I realized that there are two types of centering pins and somehow I missed either the discussion or the poll on this. Is the threaded version custom-made for a record clamping device? Which one? Also, count me in for a recognition gesture for Bryce. Somehow I don't believe the latest Listener magazine would be enough ;-) Regards, Pablo Roufogalis L. proufo@cantv.net (se dice proufo atencion de cantevepuntonet) ¡Arrobas NO!. Visite http://www.aretecnica.com/fam/od.htm Visite http://www.aretecnica.com/fampg.htm Subject: Re: [teres] Teres Picture Date: Sat, 8 Jul 2000 14:35:29 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com Guys, The optimumm side-pull balancing was worked out as the bearing/platter dimensions were being finalized, some time ago. The bearing is stable & comfortable with a pull located anywhere from the top edge of the top contact surface to the bottom edge of the bottom contact area, most of the shaft(!). The platter/spindle interface is ideally balanced through the axis of the bottom edge of the spindle collar, which the platter rests on. If you look at the way the platter, spindle, & bearing all fit together, you will find that the second center is slightly above the top edge of the top bearing/spindle contact area. Giving the bearing the higher priority, would mean that the top of that contact area is the ideal place to run the belt. This corresponds to almost exactly the middle of the platter's rim. Because of the platter's mass, and supra-industrial overdesign of the bearing, you can easily enough get away with running the belt wherever you must, if it is not convenient to place it in the middle of the platter's edge, or just below. Even the least optimal placement-above the center (the higher, the further from optimal) should be ok, but try to keep it down to as close to the middle as you can. For the sake of optimization, the best area should be between the center( i.e. top edge of the belt at the center), to 1/2" off the bottom, but, again, you can push that limit if you had to. Igor --- phclark wrote: > > ----- Original Message ----- > From: "Steve Zettel" > To: > Sent: Saturday, July 08, 2000 9:20 AM > Subject: Re: [teres] Teres Picture > > > > Hi guys, > > > > on 7/8/00 09:57, Thom Mackris at > thom_mackris@hotmail.com wrote: > > > > > Chris' belt location is preliminary, most likely > dictated by available > scrap > > > MDF from which the temporary motor pod was > built. > > Likely this is the case. Were I Chris, I'd only be > trying to demonstrate > the effect, not necessarily the mature application. > > > Do we know the center of gravity, or maybe what we > want is the location if > > it exists where a straight-line side pull equally > loads the top and the > > bottom of the bearing? > > Yes, one or two of you engineering hotshoes might > pull out the old slide > rule and derive an answer for the more challenged of > us. Like Thom, I > suspect this probably doesn't make a real > difference. I was coming from the > position of "in the small liklihood of it making a > difference where you put > the belt, is there a preference?" I doubt this > should get existential. > > > Given the clearances of the bearing, the rigidity > of the platter/spindle > > interface (barring any sort of resilient isolation > here, as some have > > indicated they might try) I don't think > "teeter-totter" will be a problem. > > I tend to agree, based on little knowledge and no > experience. > > > But then, this is an area that is open for > experimentation and comparison. > > At least, if one goes with a separate motor pod. > 8^) > > Which I am doing. I'm just looking for a > "shortcut," in case someone else > had already done the heavy thinking. > > > > I'd have to guess that the bearing will outlive > us, as long as we don't > do > > > something blatantly stupid. > > > Amen to that! > > Seconded. > > > I *think*, without any empirical evidence to back > me up 8^) that we will > > find other areas of design having more impact on > the sonic signature or > lack > > thereof, than belt height. > > Again, agreed. My point was, you have to put it > somewhere... > > > Steve Z > > Thanks for the commentary. > > Peter C > > > > ----- Original Message ----- > > > From: phclark > > > To: > > > Sent: Friday, July 07, 2000 5:28 PM > > > Subject: Re: [teres] Teres Picture > > > > > >> > > > I've been messing around with the geometry of > the three major > components. > > > My preliminary answer for motor pod/platter > alignment comes up with the > > > "reverse" of Chris' configuration of the drive > belt at the bottom of the > > > platter. Mine works out to 1" from the top. > > > > > > Question: How critical is this placement for > the conceived longevity > of > > > the bearing (assuming the belt drives > efficiently at any location)? > Logic > > > and tidiness suggest centering the belt in the > 3" dimension, and most > > > massive platter illustrations I've seen also > have the belt in the > middle. > > > It would likely be a PITA for me to move it to > the center. Needs must? > > > > > > Peter C > > > > > > > > > > > > > > > > > __________________________________________________ Do You Yahoo!? Get Yahoo! Mail – Free email you can access from anywhere! http://mail.yahoo.com/ Subject: [teres] teres - Bearing Problems Date: Fri, 28 Jul 2000 14:52:23 -0700 From: Chris Brady, Chris Brady To: teres@aiko.com Last night my Teres bearing bound up. When I disassembled the bearing the shaft was scored about 5/8" from the bottom. Arrgghh!! This is right about the top of the lower bearing journal. I talked with Bryce about this and we are both confident that the damage is not galling but rather due to a very hard (and small) foreign object getting into the bearing. To score the hard steel shaft it had to be something quite hard. We also know that what ever it was it had to have been in the bearing barrel between the two journals. There is no way that something could have gotten past the top journal. Here is our best guess as to what happened. For the first few bearings Bryce used some very fine emery cloth to do a little hand polishing of the journals inside the bearing. I did clean out the bearing before my initial assembly with a paper towel. And then several more times to clean out the oil during experimentation. Although it seems a bit unlikely, there must have been some small particles from the emery cloth that did not get cleaned out. After time a particle worked its way into the bearing journal. As I said this is only our best guess as to what happened. While this damage will be fairly easy to repair Bryce and I are quite concerned about the possibility of this happening to other Teres owners. So we decided to take a couple of actions. 1) Bryce is planning to ship me a bearing and platter and have me run it 24 hours a day for a few weeks and then disassemble and inspect it. Neither of us think that my problem had anything to do with wear or time used, but we want to be sure. 2) Get the word out to the group to make sure that your bearing is very clean when you put it together. I am sure that there are plenty of ways to insure that the bearing is clean without getting exotic. Wiping with a lint free cloth followed by a solvent flush should be adequate. Compressed air would also be a good idea if you have it. The space between the metal surfaces is only 2-3 ten-thousandths so particles that would give us problems would have to be very small and certainly could not be seen. Big particles like a hair are far to big to get in the bearing and would not cause problems. Also most small particles that are airborne, skin flakes, dust, pollen, etc. are soft enough to be totally benign. What I am trying to say with all of this rambling is that we have to be sure that there is no grit in the bearing but we don't need a clean room. While this is a distressing development, my sense is that this was just a fluke and that with good procedure it will not happen again. Chris Subject: Re: [teres] teres - Bearing Problems Date: Fri, 28 Jul 2000 16:10:40 -0700 From: Thom Mackris, Thom Mackris To: teres@aiko.com I'm sure glad that we have poor Chris doing all of this beta testing for us. The explanation sounds good to me, but Bryce was concerned enough about easing all of our fears to get a bearing out to Chris in order to put a quick 500 hours on it (running 24 x 7 ought to get us there in 20 days or so). Chris' bearing is not trashed, BTW. If we didn't have Bryce as a resource, Bryce said that Chris could polish out the small scratch - both on the shaft and in the journal. This would leave plenty of remaining bearing area on the lower half of the bearing - another benefit of our overkill design. I guess that the technique involved in filling this bearing is equivalent to owining a Ferrari and *not* taking it to Jiffy Lube for an oil change It would seem that our parts bin will now contain some lint free cloth and a can of compressed air, or whatever. Thanks for the heads up, Chris Thom ----- Original Message ----- From: Chris Brady To: Sent: Friday, July 28, 2000 2:48 PM Subject: [teres] teres - Bearing Problems Last night my Teres bearing bound up. When I disassembled the bearing the shaft was scored about 5/8" from the bottom. Arrgghh!! This is right about the top of the lower bearing journal. [snip] Subject: [teres] Back up and Running Date: Sat, 29 Jul 2000 22:15:15 -0700 From: Thom Mackris / Joan Panzella, Thom Mackris / Joan Panzella To: Teres_List Chris' Teres is back up and running. He went to the hardware store and picked up an 8 x 32 bolt to fit into the spindle hole. He chucked the spindle in a drill press and polished the burr with a rolled up piece if fine sandpaper (400 grade IIRC). This reduced the height of the lower bearing by a trivial amount. He got way neurotic about cleaning things before re-assembling. Lubricant du jour: power steering fluid ... appears to be approximately like 10 weight. I think when I finally assemble mine, I'll really flush the journal (brass) out heavily. Perhaps start with an alcohol cleaning, then lots of water (its good 'n cheap & you can use lots of it here in the drought ridden West ). More alcohol to evaporate the water, some canned air. I think this ought to be fine. The plan still remains to get a quick 500 hours on a test bearing although I grow more convinced that this is overkill. Bearing filling note: Chris picked up a syringe & determined that 12cc is just about enough. The well is almost completely full with this amount of oil. 12.5cc ought to cause some minor overflow & with 13cc you'd be sure to have a small mess to clean up. Cheers, Thom Subject: Re: [teres] Back up and Running Date: Sat, 29 Jul 2000 23:18:23 -0700 From: phclark, phclark To: teres@aiko.com In order to further my hard earned reputation for not being quite all there: I rise to extol the virtues of carburetor cleaner for this and many other applications. It will dissolve almost anything organic and has generally enough oomph to blow the particles way, too. As solvents go, it's pretty aggressive, but would be just fine, thanks, for making sure the bearings are squeaky clean before assembly. It's also good for cleaning ferrofluid out of compression drivers, just blows that stuff right out, cleans it, too. 1001 uses and it's cheap. My $0.02. Peter C ----- Original Message ----- From: "Thom Mackris / Joan Panzella" To: "Teres_List" Sent: Saturday, July 29, 2000 9:16 PM Subject: [teres] Back up and Running > Chris' Teres is back up and running. > > He went to the hardware store and picked up an 8 x 32 bolt to fit into the > spindle hole. He chucked the spindle in a drill press and polished the burr > with a rolled up piece if fine sandpaper (400 grade IIRC). This reduced the > height of the lower bearing by a trivial amount. > > He got way neurotic about cleaning things before re-assembling. Lubricant > du jour: power steering fluid ... appears to be approximately like 10 > weight. > > I think when I finally assemble mine, I'll really flush the journal (brass) > out heavily. Perhaps start with an alcohol cleaning, then lots of water > (its good 'n cheap & you can use lots of it here in the drought ridden West > ). More alcohol to evaporate the water, some canned air. I think this > ought to be fine. > > The plan still remains to get a quick 500 hours on a test bearing although I > grow more convinced that this is overkill. > > Bearing filling note: Chris picked up a syringe & determined that 12cc is > just about enough. The well is almost completely full with this amount of > oil. 12.5cc ought to cause some minor overflow & with 13cc you'd be sure to > have a small mess to clean up. > > Cheers, > Thom > > Subject: Re: [teres] Back up and Running Date: Sun, 30 Jul 2000 00:40:19 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com I'll second that, as a long time user of the stuff for a thousand and one purposes. Just be careful not to breathe this stuff, it's nasty, and will easily give you a headache. A simple breathing mask *will not stop it*. One of its convenient virtues, quick vaporization, sees to that. Once vaporized, it is in solution with the air, and will go right through a common "nuisance dust" type mask, which only works on fairly coarse particulants. A charcoal filtered type does better, though not 100%, either. Best bet is just to use it outdoors (only), and hold your breath while spraying, plus a few seconds to allow it to disperse in the breeze. The stuff contains Xylenes, typically (*really nasty*), often methylene chloride (ditto), plus assorted other easily vaporizable solvents, depending on the brand used (the most common & familiar Gumout is not the only one around nowadays). Not a one of these is even remotely good for you. Another good alternative would be the all-purpose universal solvent acetone. I always keep some around (albeit *very* carefully-it is super-flash-flammable!) as it, too has a thousand uses, and evaporates quicker than money around a new girlfriend. I think, when I get around to assembling my bearing, I'll try using lens wipes to do the wiping, then use some carb cleaner to take advantage of the pressurization to blow off anything remaining, then just let it all dry out on its own to be sure not to reintroduce any lint or other particles. There, is that paranoid enough? Igor --- phclark wrote: > In order to further my hard earned reputation for > not being quite all there: Just don't breathe the stuff, and your reputation will clear right up (). > I rise to extol the virtues of carburetor cleaner > for this and many other > applications. It will dissolve almost anything > organic and has generally > enough oomph to blow the particles way, too. As > solvents go, it's pretty > aggressive, but would be just fine, thanks, for > making sure the bearings are > squeaky clean before assembly. > > It's also good for cleaning ferrofluid out of > compression drivers, just > blows that stuff right out, cleans it, too. 1001 > uses and it's cheap. > > My $0.02. > > Peter C > > > ----- Original Message ----- > From: "Thom Mackris / Joan Panzella" > > To: "Teres_List" > Sent: Saturday, July 29, 2000 9:16 PM > Subject: [teres] Back up and Running > > > > Chris' Teres is back up and running. > > > > He went to the hardware store and picked up an 8 x > 32 bolt to fit into the > > spindle hole. He chucked the spindle in a drill > press and polished the > burr > > with a rolled up piece if fine sandpaper (400 > grade IIRC). This reduced > the > > height of the lower bearing by a trivial amount. > > > > He got way neurotic about cleaning things before > re-assembling. Lubricant > > du jour: power steering fluid ... appears to be > approximately like 10 > > weight. > > > > I think when I finally assemble mine, I'll really > flush the journal > (brass) > > out heavily. Perhaps start with an alcohol > cleaning, then lots of water > > (its good 'n cheap & you can use lots of it here > in the drought ridden > West > > ). More alcohol to evaporate the water, some > canned air. I think this > > ought to be fine. > > > > The plan still remains to get a quick 500 hours on > a test bearing although > I > > grow more convinced that this is overkill. > > > > Bearing filling note: Chris picked up a syringe & > determined that 12cc is > > just about enough. The well is almost completely > full with this amount of > > oil. 12.5cc ought to cause some minor overflow & > with 13cc you'd be sure > to > > have a small mess to clean up. > > > > Cheers, > > Thom > > > > > __________________________________________________ Do You Yahoo!? Kick off your party with Yahoo! Invites. http://invites.yahoo.com/ Subject: Re: [teres] Back up and Running Date: Sun, 30 Jul 2000 13:16:29 -0700 From: Chris Brady, Chris Brady To: teres@aiko.com I told Thom that I used 12cc's, but I checked my syringe and I actually put in 14cc's. About 15cc's should fill the bearing and the recess at the top of the bearing. It's great to have the Teres spinning again! Chris > Bearing filling note: Chris picked up a syringe & determined that 12cc is > just about enough. The well is almost completely full with this amount of > oil. 12.5cc ought to cause some minor overflow & with 13cc you'd be sure to > have a small mess to clean up. >