My 3a restorations (was: New AR 2ax Restoration)

[npt3]

As I noted in my old 2ax resto thread, I've just come into some REALLY nice 3a's - two pairs actually! I'm doing the older pair first - will post "before" pictures in due course. These will apparently only need new woofer surrounds and a good pot cleaning. The other drivers sound perfect! and re-capping hardly seems necessary.

A couple of questions for the group:

- are there preferred surround kits for the 3a woofers, or will any 12" kit do?

- the woofer in one of the pair appears to be decidedly younger than the other (it looks like the ABTech replacements I just dropped into the 2ax', with a foam "liner" in the well where the mounting screws are). Should I "match" the woofers from the other pair, or does it really not make any difference? (I'm guessing the latter.)

- pot cleaning: is it worth it to re-plate the pot contacts, or is a good Dremel cleaning and polishing all that's needed?

[npt3]

As I noted in my old 2ax resto thread, I've just come into some REALLY nice 3a's - two pairs actually! I'm doing the older pair first - will post "before" pictures in due course. These will apparently only need new woofer surrounds and a good pot cleaning. The other drivers sound perfect! and re-capping hardly seems necessary.

A couple of questions for the group:

- are there preferred surround kits for the 3a woofers, or will any 12" kit do?

- the woofer in one of the pair appears to be decidedly younger than the other (it looks like the ABTech replacements I just dropped into the 2ax', with a foam "liner" in the well where the mounting screws are). Should I "match" the woofers from the other pair, or does it really not make any difference? (I'm guessing the latter.)

- pot cleaning: is it worth it to re-plate the pot contacts, or is a good Dremel cleaning and polishing all that's needed?

[Shacky]

As I noted in my old 2ax resto thread, I've just come into some REALLY nice 3a's - two pairs actually! I'm doing the older pair first - will post "before" pictures in due course. These will apparently only need new woofer surrounds and a good pot cleaning. The other drivers sound perfect! and re-capping hardly seems necessary.

A couple of questions for the group:

- are there preferred surround kits for the 3a woofers, or will any 12" kit do?

- the woofer in one of the pair appears to be decidedly younger than the other (it looks like the ABTech replacements I just dropped into the 2ax', with a foam "liner" in the well where the mounting screws are). Should I "match" the woofers from the other pair, or does it really not make any difference? (I'm guessing the latter.)

- pot cleaning: is it worth it to re-plate the pot contacts, or is a good Dremel cleaning and polishing all that's needed?

Have you reviewed the AR 3a restoration guide?

[JKent]

Hmmm... My reply disappeared.

Anyway: I'm green with envy! Two pair!

Re your questions:

• I like MSound surrounds. Great kit and instructions, good support. Here are his refoam directions http://www.citlink.net/~msound/refoam/ and here's the kit: http://cgi.ebay.com/AR-3-AR-3a-reFoam-Kit-...kers_Subwoofers
  
• Your woofers should match.
  
• No need to re-plate. Clean them up, then apply some dielectric grease.
  

And although you didn't ask--replace those 40-year old caps. See the Restoration booki, p 16.

Good luck!

Kent

[npt3]

Have you reviewed the AR 3a restoration guide?

Absolutely - I used it extensively when I was doing the 2ax project.

[npt3]

Hmmm... My reply disappeared.

Anyway: I'm green with envy! Two pair!

Re your questions:

• I like MSound surrounds. Great kit and instructions, good support. Here are his refoam directions http://www.citlink.net/~msound/refoam/ and here's the kit: http://cgi.ebay.com/AR-3-AR-3a-reFoam-Kit-...kers_Subwoofers
  
• Your woofers should match.
  
• No need to re-plate. Clean them up, then apply some dielectric grease.
  

And although you didn't ask--replace those 40-year old caps. See the Restoration booki, p 16.

Good luck!

Kent

Yes, I'm very fortunate to have found two pair, and from a very nice owner that cared for them a LOT and treated them pretty much like I treat my own things. He even left the protective tape on the badges! :-o That will save me a little bit of Brasso.

At the very least, I can cannibalize the other pair if I need immediate replacements (e.g., pot knobs.) The pair I'm restoring are Cambridge models.

Woofers: even if the newer woofer is a Teledyne "Service Replacement Unit" that (will be) refoamed along with the older? The older woofer is the "A.4" version, and the newer one is the Tonegen "A.7" (see attached pix.) Since, with the extra pair of Norwoods that I have, I CAN match them, so this is not a problem for me - but it would be nice to see what the prevailing wisdom is here.

Thanks for the insight on the woofer refoaming kits!

I didn't ask about caps since I knew what you'd say, Kent! ;-) I guess while I'm inside cleaning the pots, though, I may as well re-cap them even though these speakers are in FAR better shape than the 2axs I just did. Time for another visit to Madisound...

[JKent]

Woofers: even if the newer woofer is a Teledyne "Service Replacement Unit" that (will be) refoamed along with the older? The older woofer is the "A.4" version, and the newer one is the Tonegen "A.7" (see attached pix.) Since, with the extra pair of Norwoods that I have, I CAN match them, so this is not a problem for me - but it would be nice to see what the prevailing wisdom is here.

OK--ya got me there. With any luck one of the authors of the Restoration Manual will chime in now with a definitive answer on that. The A4 and A7 sure look the same, so maybe... Let's wait for an expert.

Kent

[npt3]

OK--ya got me there. With any luck one of the authors of the Restoration Manual will chime in now with a definitive answer on that. The A4 and A7 sure look the same, so maybe... Let's wait for an expert.

Kent

Hey, I've chatted via email with the gent from MSound - great guy, and he loves him the Classic Speaker Pages. I'm getting my repair kits from him.

I just tried cleaning the cloth on one of the less promising grilles with Oxyclean/hot water (brush it on, let it sink in, rinse it off.) I am, however, not optimistic about retaining the grille frame integrity after soaking it and drying it. Has anyone had any success with this method (or other methods)? Can you (successfully) remove the cloth from the frame, clean it and re-install it? (I have a very good piece of original cloth from a 2ax grille that I could use on another frame, and would like to try this out.)

Lastly - thanks to all for this fantastic resource, and everyone's input. CSP is a great place.

[genek]

The pressed board material of the grille frame will swell and then dieintegrate into a pulpy mess if you let it get wet. If you want to try to clean the original fabric, you'll need to remove it and stretch it on some more water resistant frame, as it will shrink if it isn't stretched.

If you live in an area where the water has a high mineral content and don't soften your water, it will cause stains in the linen as it dries.

[npt3]

The pressed board material of the grille frame will swell and then dieintegrate into a pulpy mess if you let it get wet. If you want to try to clean the original fabric, you'll need to remove it and stretch it on some more water resistant frame, as it will shrink if it isn't stretched.

If you live in an area where the water has a high mineral content and don't soften your water, it will cause stains in the linen as it dries.

Yeah, that grille frame material is pretty spongy, as I found out. Good thing I tried it on test fabric that was attached to an already-dodgy frame! The Oxyclean does work really, really well, though (no mineral worries with my town water.) My wife has a needlepoint scroll frame that might work well for stretching wet linen.

[mrbruce4]

I've had good luck with using Oxyclean and slightly warm water in a bathtub. Using a medium bristle nylon brush, I've only allowed the cloth, while still on the frame, to stay less than one minute while I brush the cloth. A quick cool water rinse and then outside in the sun. Shake and use a hair dryer to get the majority of the water off and then let them lie flat on a raised open air support. Turn them after a little while and they turned out fine. I live in the desert so we had high temps and low humidity which means the grill is dry to the touch in about 20-30 minutes. I've done about 5 sets like this and it works here. As others have correctly pointed out, you do not want to let the frames soak up a lot of water.

I think this works because I limit the time in the water, get the excess water off in a hurry and get them air dry quickly. I imagine this wouldn't work well in a humid climate or in low temps.

[npt3]

I've had good luck with using Oxyclean and slightly warm water in a bathtub. Using a medium bristle nylon brush, I've only allowed the cloth, while still on the frame, to stay less than one minute while I brush the cloth. A quick cool water rinse and then outside in the sun. Shake and use a hair dryer to get the majority of the water off and then let them lie flat on a raised open air support. Turn them after a little while and they turned out fine. I live in the desert so we had high temps and low humidity which means the grill is dry to the touch in about 20-30 minutes. I've done about 5 sets like this and it works here. As others have correctly pointed out, you do not want to let the frames soak up a lot of water.

I think this works because I limit the time in the water, get the excess water off in a hurry and get them air dry quickly. I imagine this wouldn't work well in a humid climate or in low temps.

That would certainly explain why my frame got as soggy as it did - I really soaked the hell out of it (e.g., brushed in the Oxyclean solution and let it soak in for about 5 minutes, then rinse it very well. A LOT of brown gunk came off and the linen looks great. The frame, um, not as fabulous. I think I can carefully salvage the fabric and attach it to a new frame, though.

[npt3]

Enough about grilles for now: let's talk cabinets.

My cabs are, except for some unfortunate but not horrible water rings on the top (oh, the humanity!) and a couple of very minor scratches, in really, really good shape, and I'd like to keep their appearance as close to "stock" as possible. But I would like them to be as 'unblemished' as I can make them, too.

I've had a very good browse around CSP on this to see what others have done. For me, the absolutely least intrusive method seems to be applying Howard's Restor-A-Finish, wipe off, dry, then apply Howard's Feed-N-Wax. A next level up would be applying RAF using 0000 steel wool with the wood grain to gently even out the finish, wipe, dry, then FNW.

I picked up some walnut RAF and tried it out (using steel wool) on the bottom of one of my units, which was kind of beat up and therefore a good test surface. It performed as advertised: the grain and color stands out better, but the color is not deeper or lighter than before. Good!

My questions are about (the very well-regarded) Watco danish oil, which I know AR used themselves in their factory:

• Is the Watco "dark walnut" color closest to the AR oiled walnut finish? (it looks like it is.)
  
• If I apply it after RAF, do I need some kind of finish on top of that, or is the Watco oil enough?
  
• If no finish is applied after the Watco oil, how do I maintain the cabinets after that?
  

[genek]

Are your water rings light or dark? If they're light, then rubbing with RAF or some other naptha-based "restorer" may remove them. If black, the only way to remove them is to bleach and stain. Black water stains are caused by iron in water reacting with tannins in wood, and they likely go all the way through the veneer. If the stain is really "not horrible," the easiest way to deal may be to just stain the cabinets darker to help hide them.

AR walnut cabinets seem to fall into two general color ranges, medium dark with a reddish tone and really dark with a brown tone. Either would be "authentic."

RAF is not a finish, but Watco is (penetrating oil + catalyzed varnish). An occasional application of wax or an oil-based furniture polish should be all that is needed to maintain it.

[RoyC]

Be careful using steel wool, as particles will be attracted to the magnetic field of the drivers, and become stuck to the domes and cones.

Attached are photos of a recent 3a restoration I completed for a CSP member, using 180 to 600 grit sandpaper, and Watco medium walnut (dark walnut works well too). The water rings you mentioned can usually be removed with sanding. I don't use anything on top of the Watco.

Roy

[npt3]

Be careful using steel wool, as particles will be attracted to the magnetic field of the drivers, and become stuck to the domes and cones.

Attached are photos of a recent 3a restoration I completed for a CSP member, using 180 to 600 grit sandpaper, and Watco medium walnut (dark walnut works well too). The water rings you mentioned can usually be removed with sanding. I don't use anything on top of the Watco.

Roy

Eep! Good advice about the steel wool bits, Roy - I hadn't considered that - I'll make sure to avoid that. When I'm ready to really do the cabinets, I intend on covering the front and back faces with a sheet of plastic dropcloth cut to fit, and sealing the edges securely (but temporarily) with duct or painters' tape.

'

[JKent]

Just to follow up on a few points (I agree with Gene and Roy).

RAF does a great job and is maybe the least invasive. You CAN (and probably should) put Watco Oil over it. You CANNOT put any varnish or poly over it. In cases where you want more gloss than the Watco Oil provides, you can use Minwax Antique Oil or Tung Oil.

The RAF SHOULD be applied with very fine steel wool (00000 is good). When using it wet there is little danger of stray steel wool particles, but Roy is right: Be careful. Your idea of sealing the front can’t hurt, but use PAINTER’s tape—not duct tape. Duct tape is good for many things, but leaves a residue and is not suitable for masking.

For your water ring, here’s a tip from Heloise: Mayonnaise + ash (fireplace or cigarette). Make a paste, rub it in, let it set overnight, wipe off.

The veneer on the old AR cabinets is pretty thick, so you CAN sand as Roy described. Just be very careful at the edges and corners. Use a flat sanding block and keep it level! f you do a little careful sanding, then use the Mayo/ash trick, then RAF I’ll bet the ring will pretty much disappear. Follow up with Watco and you’re all set.

btw—You can get RAF in Walnut and Dark Walnut. Watco comes in those shades and also neutral. IMO, if you use the dark walnut RAF you can use neutral Watco oil so you won’t make your cabinets TOO dark.

Here is a great article on obtaining a “super smooth oil finish” using Watco:

http://antiquerestorers.com/Articles/SAL/smothoil.htm

To maintain a Watco Oil finish, just dust it. You may use wax if you like (Howard's Feed-n-Wax is very good) or you could apply another light coat of Watco Oil every couple of years. I "think" AR used to recommend wiping the veneer with mineral oil to bring it back to new condition, but if you are going to apply any kind of oil for maintenance, I'd stick with Watco.

Good luck and be sure to post photos!

Kent

[npt3]

Just to follow up on a few points (I agree with Gene and Roy).

RAF does a great job and is maybe the least invasive. You CAN (and probably should) put Watco Oil over it. You CANNOT put any varnish or poly over it. In cases where you want more gloss than the Watco Oil provides, you can use Minwax Antique Oil or Tung Oil.

The RAF SHOULD be applied with very fine steel wool (00000 is good). When using it wet there is little danger of stray steel wool particles, but Roy is right: Be careful. Your idea of sealing the front can’t hurt, but use PAINTER’s tape—not duct tape. Duct tape is good for many things, but leaves a residue and is not suitable for masking.

For your water ring, here’s a tip from Heloise: Mayonnaise + ash (fireplace or cigarette). Make a paste, rub it in, let it set overnight, wipe off.

The veneer on the old AR cabinets is pretty thick, so you CAN sand as Roy described. Just be very careful at the edges and corners. Use a flat sanding block and keep it level! f you do a little careful sanding, then use the Mayo/ash trick, then RAF I’ll bet the ring will pretty much disappear. Follow up with Watco and you’re all set.

btw—You can get RAF in Walnut and Dark Walnut. Watco comes in those shades and also neutral. IMO, if you use the dark walnut RAF you can use neutral Watco oil so you won’t make your cabinets TOO dark.

Here is a great article on obtaining a “super smooth oil finish” using Watco:

http://antiquerestorers.com/Articles/SAL/smothoil.htm

To maintain a Watco Oil finish, just dust it. You may use wax if you like (Howard's Feed-n-Wax is very good) or you could apply another light coat of Watco Oil every couple of years. I "think" AR used to recommend wiping the veneer with mineral oil to bring it back to new condition, but if you are going to apply any kind of oil for maintenance, I'd stick with Watco.

Good luck and be sure to post photos!

Kent

RAF is great, but I think it is proving to be no match for the dark rings on top of one my cabs. I do think I'll need to do some >judicious< fine/extra fine sanding and Watco staining. No big; they'll look super afterwards. I had great success using my random orbital sander in my 2ax project; has anyone worked with one successfully, or should I really just stick with hand sanding?

[genek]

RAF is great, but I think it is proving to be no match for the dark rings on top of one my cabs. I do think I'll need to do some >judicious< fine/extra fine sanding and Watco staining. No big; they'll look super afterwards. I had great success using my random orbital sander in my 2ax project; has anyone worked with one successfully, or should I really just stick with hand sanding?

RAF only works on light/white water marks, which are caused by moisture that has worked into the finish. Dark water marks are a chemical reaction between iron in water and tannin in wood and are in the fibers. If you can't sand through them to find clean wood, the only way to remove the stain is to bleach it.

[npt3]

RAF only works on light/white water marks, which are caused by moisture that has worked into the finish. Dark water marks are a chemical reaction between iron in water and tannin in wood and are in the fibers. If you can't sand through them to find clean wood, the only way to remove the stain is to bleach it.

You're right of course on the bleaching, Gene. I'm going to have to do that, probably following it up with sanding and restaining (which is OK with me.)

But on sanding, would using the random orbital with, say, 220 grit paper be Bad?

[genek]

You're right of course on the bleaching, Gene. I'm going to have to do that, probably following it up with sanding and restaining (which is OK with me.)

But on sanding, would using the random orbital with, say, 220 grit paper be Bad?

Probably not, as long as you are very careful and don't apply too much pressure. But if I was bleaching a dark ring out first and then just prepping for stain rather than trying to grind through the ring to clean wood, I'd probably start with 320.

[npt3]

A quick word about MSound: great! I have to refoam all of my 3a woofers, and the kits and instructions John provides are just awesome. So easy, my pug could probably do it. I started with an extra 2ax woofer I had, and it came out great if I say so myself.

[npt3]

I have a (totally newbie) question about caps. The conventional wisdom (and that preached in the Resto Guide) is that old caps (my 3as are about '74-'76 vintage) have drifted from their original values. I have no doubt that replacing the caps with Solens or the like is a prudent thing to do. That said, if the caps have drifted, how can you tell - i.e., is this noticeable audibly?

[RoyC]

I have a (totally newbie) question about caps. The conventional wisdom (and that preached in the Resto Guide) is that old caps (my 3as are about '74-'76 vintage) have drifted from their original values. I have no doubt that replacing the caps with Solens or the like is a prudent thing to do. That said, if the caps have drifted, how can you tell - i.e., is this noticeable audibly?

Measuring with a capacitance meter will give you a general idea of the condition of the caps. Direct comparison with the same model (and era) speaker known to have good caps can provide clues as well.

BTW, I completely agree with you regarding MSound. John is very aware of the need for very compliant surrounds in the AR world. He has recently introduced new surrounds for 8 and 10 inch AR woofers (as an alternative to the already proven JBL surrounds), and offers a variety of dust caps. Even though his prices are very good to begin with, he will provide a discount to CSP members. Many other surround sellers are offering surrounds for AR woofers which are too stiff/not compliant enough.

Roy

[Razor313]

A quick word about MSound: great! I have to refoam all of my 3a woofers, and the kits and instructions John provides are just awesome. So easy, my pug could probably do it. I started with an extra 2ax woofer I had, and it came out great if I say so myself.

ditto to that regards John and MSound. I just got finished refoaming my AR 5 woofers with the kit from John on recommendations from CSP posts. The hardest part of the job was getting the USPS box opened. Great kit from John.