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Doc Mark
11-14-2008, 09:43 AM
Good Morning, Friends,

Well, it's about time to do some light sanding, and a good re-oiling of my 4411 cabinets, and also a few other's I have on hand. In their old "JBL Enclosure Information Manual", they recommended using "6/0" sandpaper for beginning that task. What, exactly, is "6/0 " sandpaper? I've not heard of that before. After the initial sanding with this paper, and first oiling of the veneer, they recommended going to 360 grit wet-and-dry sandpaper, and several more sanding/oiling sessions, to finish the job.

Since I'm only taking out small scratches on the 4411's, I'm thinking that "6/0" sandpaper, whatever that might be, may well not be needed, at all, and that I should just use the 360 W&D paper. What do you recommend for such a task, please? I tried to use the search function to find info on this, but pretty much came up empty.

When finished with the 4411's, I'd also like to re-oil the L300's, but they do not need sanding, as far as I can see. Thanks, very much, for your suggestions and guidance on this, Friends! Take care, and God Bless!

Every Good Wish,
Doc

brutal
11-14-2008, 10:23 AM
Depending on the depth of scratches, and estimated thickness of the veneer (those pesky LxxT floor standers are THIN), I normally start with 120, then work into 220 and lastly 320. Always use a solid sanding block and take care near the edges/corners. If the scratches are simply superficial, I'd wipe the cabs down with mineral spirits to de-glaze the finish somewhat and remove any residual waxes, dirt, etc. then get after them with 220 until the old finish is gone. I prefer the synthetic non-clogging papers, but el-cheapo stuff for the initial finish removal as the old oils will clog up most anything anyway.

What are you planning to use for "oil?" I prefer Watco Danish oil as it sets up a nice durable finish. I think it has some polymers in it that harden the wood more than JBL's Gum Turpentine/Boiled Linseed Oil concoction.

Doc Mark
11-14-2008, 10:44 AM
Hey, Brutal,

Thanks, very much, for your thoughts on this! I can take a few photos of the scratched areas on the 4411's, and post them for you to see. But, they do not appear to be too deep, and should respond to a bit of TLC. From previous posts on oil choices, I did get two kinds of Watco Danish Oil, both "natural", and "medium walnut". I was going to try them both out, at different places, on an old single 44312A enclosure that I have, and see which finish I like best. Any thoughts on which you would suggest? Thanks, again, and I'll try to take the "scratch" photos in an hour, or so. Take care, and God Bless!

Every Good Wish,
Doc

Baron030
11-14-2008, 11:43 AM
In their old "JBL Enclosure Information Manual", they recommended using "6/0" sandpaper for beginning that task. What, exactly, is "6/0 " sandpaper?
Hi Doc

That's a good question.

So, I googled 6/0 sandpaper and I turned up a site with a crosswalk table.

Link: http://www.sizes.com/tools/sandpaper.htm

It turns out 6/0 sandpaper is equal to 220 grit.

Now, from my own experiences, there are some slight differences even within a grit size as to its cutting speed.
Silicon carbide has the hardest and sharpest grit shape, so it will cut the fastest of all the common abrasives.
Aluminum oxide has a slightly more rounded grit shape and will cut a just little bit slower.
Garnet, Emery, Flint are all naturally occurring abrasives.
And as result are softer and will cut slower and they also wear out the fastest.

Since, you are working on a veneered enclosure.
I would recommend that you use something finer then 220 grit.
Otherwise, you could very quickly cut right though the veneer.
And that would not be a good thing.

Baron030:)

rdgrimes
11-14-2008, 12:31 PM
I'm using 220 grit to start, then 320, then 400. 150 grit can be used on deep scratches, but 150 WILL go through the veneer pretty fast on the edges and corners.

Using Tung Oil, I like either Minwax Tung Oil or Formby's Low Gloss Tung Oil. Tung oil has no stain, but is mainly penetrating oil with a small amount of urethane. You get a very minimal gloss but bullet-proof finish.

I recommend avoiding any stains unless you need to deal with fading. Danish Oil and Tung Oil are very similar.

Use of 6-0 steel wool to apply the tung oil 1st coat works nice for polishing. After 24 hrs, a light buff with dry 6-0 steel wool will remove all the little sharpies and dust and further polish. Use a soft lint-free cloth to apply a second coat. 3rd coat will add more gloss.

brutal
11-14-2008, 01:26 PM
Hey, Brutal,

Thanks, very much, for your thoughts on this! I can take a few photos of the scratched areas on the 4411's, and post them for you to see. But, they do not appear to be too deep, and should respond to a bit of TLC. From previous posts on oil choices, I did get two kinds of Watco Danish Oil, both "natural", and "medium walnut". I was going to try them both out, at different places, on an old single 44312A enclosure that I have, and see which finish I like best. Any thoughts on which you would suggest? Thanks, again, and I'll try to take the "scratch" photos in an hour, or so. Take care, and God Bless!

Every Good Wish,
Doc

I've always used the Watco natural. That said, if I'm just sprucing up some dirty cabs, I'll hit them with Howard's Restore-A-Finish and a fine synthetic pad (aka scotchbrite sanding pads), followed by Watco, and lastly, some Howard's Feed-N-Wax.

I'm very leery of using "true" Tung oil as I've seen others end up with some disastrous results when other finishes are encountered and the tung reacts adversely with the old finish. 100% pure Tung oil makes me nervous if there were to be any future finishes applied as well. Unfortunately, Tung Oil (blends) and Danish Oil can be the same thing depending on the blends involved. Here's a good but brief read on the differences. http://www.sawmillcreek.org/showthread.php?t=15837

Since you already have the Watco, and we know it's a safe product, I'd stick with it. The natural is going to produce a lighter finish than the Gum Turpentine/Boiled Linseed Oil JBL used (the Linseed Oil darkens the wood), but I think makes for a better looking finish. I usually apply at least three coats, the 1st and 2nd rather heavy as it will soak in quickly. Sand/buff between coats and you will get outstanding results.

Doc Mark
11-14-2008, 01:53 PM
Hey, Guys,

Thanks, very much, for the suggestions, and definitions! I will go ahead with the Watco Danish Oil, as I already bought it, and would like to see how it works. Before I jump into the 4411's, I will "practice" on that old 4312A cabinet down in the Hobbit Hole. I'll use the natural Watco on one side, and the medium walnut on the other side, with some other oils on the top and bottom, then compare the results. As our L300's do have a small bit of sun-fading in a few places, I may use the darker stuff on them. But, it all depends on which oil I like better, after having compared them on that old JBL cabinet.

As promised, I'm posting a couple of photos of the 4411's, and you can easily see which side was the "down" side. It appears that previous owners never used them in the horizontal position, but rather on end, with the woofer down. The "top", or opposite side, is shown as a comparison, and it's easy to see that it's in better shape, overall. Not too much work, in any case, and I hope to get to it later today, or tomorrow. I will take some photos of that old 4312A, showing the differences between natural, medium walnut, and also another oil finish that I picked up, with orange oil in it. Thanks, again, Friends, and God Bless!

Every Good Wish,
Doc

SMKSoundPro
11-14-2008, 01:59 PM
Dear Doc,

I am so glad you are putting so much time and detail into these 4411's.

I have a pair in my shop also, and have been refoaming the drivers, while reading your posts. All drivers are done and now comes the cabs.

Someone drilled large holes in the back and installed hubbell twistlocks. Seems a bit extravagant. So I am plugging the holes with a piece of 1/4" ply on the inside and will fill the hole on the back with a wodden plug from a hole saw scrap. Then fill with bondo and re-paint the backs black.

Mine have many rough scuff marks all over the walnut veneer, and I have sanded them with 220, then 320. In the sound shop I worked in for 17 years, we put 400 grit wet/dry sand paper on the random orbit sander and "wet-sanded" the Watco oil right into the veneer. The oil as a lubricant and staining agent at the same time. The result was amazing. A super smooth oiled finish. Let dry completely. BURN all watco oil cloths and rags!!! Then a couple days later, rubbed in some watco wax with the same random orbit sander only fitted with a polishing pad. The results are very good.

Post pics when you can. I will too. My 4411's are not a mirror image pair, but should still sound pretty good. Can't wait.

Good luck!
Scotty.

SMKSoundPro
11-14-2008, 02:04 PM
Try the Medium Walnut Watco as it will blend the newer scratches and the good veneer and blend the whole lot together.

Sort of like a drag queen makeover, gotta cover the beard with trowell grade spackle.

I am pretty sure you get the picture.

smk.

grumpy
11-14-2008, 02:13 PM
question (sorry if it has been asked before):

Can one mitigate dents/grooves where the wood fibers were essentially crushed
(as opposed to material being removed) by carefully moistening or steaming the
area... -before- sanding (or after a very light sanding to remove the finish)?

SMKSoundPro
11-14-2008, 02:28 PM
I understand that a clothes iron will steam and "fluff" the wood - within reason.

A deep dent is exactly that. Too much heat will lift the veneer. Reheat will attach the veneer.

Be careful, and don't tell the iron owner and clean any residue before she irons her Sunday blouse!

Allanvh5150
11-14-2008, 02:29 PM
And to follow up Grumpy, saliva works much better than water. I would go for the steel wool for finishing as well.:)

brutal
11-14-2008, 04:12 PM
A few of those gouges look deep enough that you may burn through the veneer trying to get them out. I'd be very, very cautious after getting through the superficial ones.

Doc Mark
11-14-2008, 05:35 PM
Hey, All,

I went down to our local Village hardware store, which is an Ace Hardware, and procured three sheets each of 220, 320, 400, and 600 wet and dry paper. It's made in Finland, which sort of surprised me. Bet it's good stuff, then!

In any case, work got in the way of my plans for doing this today, but I'm still hoping to get it done this weekend, or early next week. I'm going to be posting a photo which was sent to me by the fellow who sold me the 4411's, and you will easily see how the tops and bottoms got somewhat scratched up, especially compared to the sides, which are in pretty good shape. The 4411's are stacked in the very tiny kitchen of his crammed-to-the-gills mobile home!! :blink::blink: Thanks, again, for all the encouragement and nice comments, Friends!! I'll post another note when all is said and done, with photos of the results. Take care, and God Bless!

Every Good Wish,
Doc

westend
11-17-2008, 12:08 AM
Hey, All,

I went down to our local Village hardware store, which is an Ace Hardware, and procured three sheets each of 220, 320, 400, and 600 wet and dry paper. It's made in Finland, which sort of surprised me. Bet it's good stuff, then!

In any case, work got in the way of my plans for doing this today, but I'm still hoping to get it done this weekend, or early next week. I'm going to be posting a photo which was sent to me by the fellow who sold me the 4411's, and you will easily see how the tops and bottoms got somewhat scratched up, especially compared to the sides, which are in pretty good shape. The 4411's are stacked in the very tiny kitchen of his crammed-to-the-gills mobile home!! :blink::blink: Thanks, again, for all the encouragement and nice comments, Friends!! I'll post another note when all is said and done, with photos of the results. Take care, and God Bless!

Every Good Wish,
Doc
Great project! I recently refinished a pair of JBL 4313 Studio Monitors, Oiled Walnut cabs. I used Watco Walnut. They turned out very nice.

brutal
11-17-2008, 01:15 AM
pair of 4311B's I did with Watco natural, and sold (for a pittance)


http://img.auctiva.com/imgdata/6/0/2/1/4/1/webimg/193828470_o.jpg

Doc Mark
11-17-2008, 07:09 AM
Hey, Brutal,

Very nice, indeed!! A lack of time has now intruded on my desire to get the 4411 cabinets up to snuff, and so this project will have a wait just a bit, as have many other fun projects I've wanted to complete! :( Hopefully, after Thanksgiving, work will settle down and I'll be able to get this one done, and start on a few others, too! Thanks, again, for sharing your great success with the Watco! Take care, and God Bless!

Every Good Wish,
Doc

westend
11-17-2008, 05:19 PM
pair of 4311B's I did with Watco natural, and sold (for a pittance)


http://img.auctiva.com/imgdata/6/0/2/1/4/1/webimg/193828470_o.jpg
Nice work, they look great! :applaud:
I understand about the "pittance" part of this. It's impossible to recover the time and cost when dealing with the Studio Monitors, IMO.

brutal
11-17-2008, 09:55 PM
I'm still kicking myself over this.

They ended up going for about $35 over what I paid for them. All the time I put into them... painted the baffles and backs, new foam on the LE25-2's. I made $20 not including my time. Oh well, refinishing is therapeutic for me.

Worst part is I had a buyer off the CL ad willing to go the e-bay route and I missed his e-mail waiting for me to confirm the final price so I could end the auction to the high bidder (him.)

Some other flake that NEVER leaves feedback for sellers got em for $100 less.

I just have too many sets in the house right now, something had to give and I'm not particularly fond of the L100/4311 genre. The 4310's are staying for posterity's sake (plus I paid $200 for them and $189 for a pair of NOS 2105H to make them right.)

westend
11-18-2008, 02:34 PM
I'm still kicking myself over this.

They ended up going for about $35 over what I paid for them. All the time I put into them... painted the baffles and backs, new foam on the LE25-2's. I made $20 not including my time. Oh well, refinishing is therapeutic for me.

Worst part is I had a buyer off the CL ad willing to go the e-bay route and I missed his e-mail waiting for me to confirm the final price so I could end the auction to the high bidder (him.)

Some other flake that NEVER leaves feedback for sellers got em for $100 less.

I just have too many sets in the house right now, something had to give and I'm not particularly fond of the L100/4311 genre. The 4310's are staying for posterity's sake (plus I paid $200 for them and $189 for a pair of NOS 2105H to make them right.)
Understand, completely. If nothing else, you've probably made the pair more appreciable and at some time a user will cherish them and care for them as you did. Gotta' hope for that, I guess.
I am thinking of selling the JBL 4313 Monitors I just refinished. Didn't think I'd ever sell them. They are just a really nice package for small rooms and nearfield. Alas, can't hand them down to the kids and I need the space so I will probably sell them, along with a couple of other pairs. I won't loose any money on them but certainly won't get paid for the time I have in them.