Hi Navin, Al
Dunno 'bout new name for thread - welcome back Navin ?
Al - the individual layers I cut all glued together fine, but after some time I noticed on 3 of the layers on one of the cabs, the layer itself split horizontally all the way around (not at glue join, but in between) The bracing I used is all heavilly glued in place, and the veneer is also in place, and totally unremovable.
So I really don't know whether it can be saved. If it can't I'll be making more of a watt/puppy lookalike, with a deeper cab and an angle that starts halfway up the bass cab at the back, and runs up to meet the back of the angled mid/tweet enclosure. Its more about the time than money tbh - I'm moving soon (hopefully within 4 weeks), and want to get this project moving before the summer kicks in!
Cheers
Rob
Dunno 'bout new name for thread - welcome back Navin ?
Al - the individual layers I cut all glued together fine, but after some time I noticed on 3 of the layers on one of the cabs, the layer itself split horizontally all the way around (not at glue join, but in between) The bracing I used is all heavilly glued in place, and the veneer is also in place, and totally unremovable.
So I really don't know whether it can be saved. If it can't I'll be making more of a watt/puppy lookalike, with a deeper cab and an angle that starts halfway up the bass cab at the back, and runs up to meet the back of the angled mid/tweet enclosure. Its more about the time than money tbh - I'm moving soon (hopefully within 4 weeks), and want to get this project moving before the summer kicks in!
Cheers
Rob
Navin, I almost forgot the title of this thread, welcome back
Rob
The cab is probably still fairly OK structurally, you just nedd to reinforce the splits. The best way to do this is to buy some 2 part epoxy, not the glue type, but the type used for boat/car body repairs with glass fibre matting.
Using a syringe ( you can buy them at a chemists), inject as much of the mixed resin as possible into the cracks. This resin is thinner than the glue type and should flow well enough to get a fair amount in, if the cracks are too small to get the needle in, just drill a few holes with a small drill bit slightly larger than the needle, and use those. You could then use a little of the glass fibre matting over the cracks, with more epoxy dabbed on with a brush.
Good luck
Rob
The cab is probably still fairly OK structurally, you just nedd to reinforce the splits. The best way to do this is to buy some 2 part epoxy, not the glue type, but the type used for boat/car body repairs with glass fibre matting.
Using a syringe ( you can buy them at a chemists), inject as much of the mixed resin as possible into the cracks. This resin is thinner than the glue type and should flow well enough to get a fair amount in, if the cracks are too small to get the needle in, just drill a few holes with a small drill bit slightly larger than the needle, and use those. You could then use a little of the glass fibre matting over the cracks, with more epoxy dabbed on with a brush.
Good luck
Hi Al,
I can see what you're saying, but the cracks are hairline - not a single bit of a gap to inject into.(the vertical bracing is holding it all tightly) If I drilled into it, wouldn't I have to route a channel all the way round and then fill that? If so a router is too big to do this.-Any other tools?
You don't think this will affect the sound quality? - If its just a case of air sealing then there isn't a problem. I was worried that the cracks would affect the sound, and thats why I was going to build new ones. I'd rather use the ones I've already built
Cheers
Rob
I can see what you're saying, but the cracks are hairline - not a single bit of a gap to inject into.(the vertical bracing is holding it all tightly) If I drilled into it, wouldn't I have to route a channel all the way round and then fill that? If so a router is too big to do this.-Any other tools?
You don't think this will affect the sound quality? - If its just a case of air sealing then there isn't a problem. I was worried that the cracks would affect the sound, and thats why I was going to build new ones. I'd rather use the ones I've already built
Cheers
Rob
RobWells said:I can see what you're saying, but the cracks are hairline - not a single bit of a gap to inject into.(the vertical bracing is holding it all tightly) If I drilled into it, wouldn't I have to route a channel all the way round and then fill that? If so a router is too big to do this.-Any other tools?
You don't think this will affect the sound quality? - If its just a case of air sealing then there isn't a problem. I was worried that the cracks would affect the sound, and thats why I was going to build new ones. I'd rather use the ones I've already built
Id they are that small, the approach i would take would be to load those areas with as much plastic as you can get to seep into the MDF (thinned polyurathane, perhaps the epoxy pinkmouse is talking about), then i would lay a fiberglass patch over it... you should be fine. If you can detect a difference in the 2 boxes then you can start planning other ones. (of course it wouldn't hurt to do all the inside.
When you 1st described it, i imaginned that the pieces had come completely asunder.
dave
RobWells said:
In that case, just dab as much into the crack as possible, then use the matting to cover the cracks, it should be fine.
The splitting may well be caused my changes in humidity causing the mdf/ bracing/veneer to try and expand or contract- did you leave them in the garage during the cold damp weather we have been having?
Hi Dave, Al
I'll be off to buy some resin/matting today then!
Al, I am working on the cabs at the factory I work at - Its a huge place that uses the big gas heaters (blow hot air out) Yes the temp does go up and down a lot - esp in the recent cold snaps we've been having.
I sealed all the inside of the cabs by rollering wood glue all over it - I'm assuming I'll have to sand all that off before I apply the resin?
I'm starting to like these cabs again
Rob
I'll be off to buy some resin/matting today then!
Al, I am working on the cabs at the factory I work at - Its a huge place that uses the big gas heaters (blow hot air out) Yes the temp does go up and down a lot - esp in the recent cold snaps we've been having.
I sealed all the inside of the cabs by rollering wood glue all over it - I'm assuming I'll have to sand all that off before I apply the resin?
I'm starting to like these cabs again
Rob
RobWells said:
Yes, you should sand off the wood glue as much as possible, but don't worry particularly about getting every single scrap off.
The sealing may be part cause of the problem, by holding any moisture in the wood from the gluing and veneering, rather than letting it dry naturally, the adhesive bonding the MDF may have weakened.
Hi Al,
I glued the layers 2 at a time over the space of a week. I sealed the insides on a monday after the last layer went on on the friday. The veneering was done at least 1 week after the inside was sealed. I'm pretty sure I left enough time between 'stages'.
I reckon it's more likely to be temperature change, but it's done now
I'm staying late at work tomorrow to apply the resin/fibreglass matting. I'm doing both cabs the same to keep them equal.
The veneer has formed a few bubbles from using clamps whilst glueing the top onto the cab(I never realised how 'squashable' mdf was!), but this was/will be easily fixed by slicing with a scalpel and re-ironing. I'll be using french polish (shellac) to finish them.
Hopefully I'll be able to post a finished pic (of the bass units) within 2 weeks. I've been really looking into my x-over, and have a good idea of what needs to be done. I'll need a lot of help with the maths when I do this so dust down your calculators chaps
I'll let you know how the resin stuff goes..
Cheers
Rob
I glued the layers 2 at a time over the space of a week. I sealed the insides on a monday after the last layer went on on the friday. The veneering was done at least 1 week after the inside was sealed. I'm pretty sure I left enough time between 'stages'.
I reckon it's more likely to be temperature change, but it's done now
I'm staying late at work tomorrow to apply the resin/fibreglass matting. I'm doing both cabs the same to keep them equal.
The veneer has formed a few bubbles from using clamps whilst glueing the top onto the cab(I never realised how 'squashable' mdf was!), but this was/will be easily fixed by slicing with a scalpel and re-ironing. I'll be using french polish (shellac) to finish them.
Hopefully I'll be able to post a finished pic (of the bass units) within 2 weeks. I've been really looking into my x-over, and have a good idea of what needs to be done. I'll need a lot of help with the maths when I do this so dust down your calculators chaps
I'll let you know how the resin stuff goes..
Cheers
Rob
do let us know if the sound is different from the other cabinet.
i find resin bonded fiberglass matting to be an excellent sealer. messy but good. i built fiberglass boat hulls during a summer job (many years ago) and found that the best combination is matting combined with loose rovings at stress points (corners etc).
i find resin bonded fiberglass matting to be an excellent sealer. messy but good. i built fiberglass boat hulls during a summer job (many years ago) and found that the best combination is matting combined with loose rovings at stress points (corners etc).
Hi Rob
Nice to hear that you haven't given up hope. I know how disheartening it can be when a project doesn't go according to plan.
If you're doing repairs to the MDF I assume that you'll need to remove some of the veneer first. If you pull a few thin strips off maybe you can replace these with black or contrasting colour strips that become a feature. Depending on the location of the three splits this might look quite good (especially if you do the same on the other speaker... ).
Any reason why you are using shellac finish? Its quite a lot of work to get looking good, and there are lots of modern finishes that can look great and will be lots more durable too (eg polyurethane or rubbed danish oil or similar).
Which revelator mid are you using? The 12M, or one of the larger bass mid units?
Mick
Nice to hear that you haven't given up hope. I know how disheartening it can be when a project doesn't go according to plan.
If you're doing repairs to the MDF I assume that you'll need to remove some of the veneer first. If you pull a few thin strips off maybe you can replace these with black or contrasting colour strips that become a feature. Depending on the location of the three splits this might look quite good (especially if you do the same on the other speaker... ).
Any reason why you are using shellac finish? Its quite a lot of work to get looking good, and there are lots of modern finishes that can look great and will be lots more durable too (eg polyurethane or rubbed danish oil or similar).
Which revelator mid are you using? The 12M, or one of the larger bass mid units?
Mick
Hi Mick,
There's no way the veneer will come off cleanly - I had a bit of a problem at the join at the back, and had to move it 10mm to one side, meaning I had to remove 10mm of veneer. That was bad enough. The stuff I've got has a 'plasticy' backing(smells like perspex when you route it) and leaves this behind in places.
I used the resin last night on the cab, and it soaked in nicely. Then I covered with fibreglass matting and more resin. Seems quite solid, but I'll only know for sure when (if) I hear no difference between good and bad cab..
The mid I bought is this one:
http://www.d-s-t.com/scs/data/15w_8530k00a.htm
It has a boost of 4Db above 2Khz, which means I'll be converting the spare buffer on my 24Db LR x/o to a shelving low pass filter to straighten. (Using only 12Db/octave) on mid/tweet.
I'm still messing with the cabs for the mid/tweet. I'm concentrating on finishing the bass bits first..
Also got my Linkwitz Transform boards ready aswell. Slowly but surely I shall get there
I was recommended shellac by someone in the trade. Mind you nothing is set in concrete...
Cheers
Rob
There's no way the veneer will come off cleanly - I had a bit of a problem at the join at the back, and had to move it 10mm to one side, meaning I had to remove 10mm of veneer. That was bad enough. The stuff I've got has a 'plasticy' backing(smells like perspex when you route it) and leaves this behind in places.
I used the resin last night on the cab, and it soaked in nicely. Then I covered with fibreglass matting and more resin. Seems quite solid, but I'll only know for sure when (if) I hear no difference between good and bad cab..
The mid I bought is this one:
http://www.d-s-t.com/scs/data/15w_8530k00a.htm
It has a boost of 4Db above 2Khz, which means I'll be converting the spare buffer on my 24Db LR x/o to a shelving low pass filter to straighten. (Using only 12Db/octave) on mid/tweet.
I'm still messing with the cabs for the mid/tweet. I'm concentrating on finishing the bass bits first..
Also got my Linkwitz Transform boards ready aswell. Slowly but surely I shall get there
I was recommended shellac by someone in the trade. Mind you nothing is set in concrete...
Cheers
Rob
i am looking for a finish that will give a mirror black look to my speaker.
i know i am still far away from painting or polishing it but i would like to ask for ideas.
i want the cabinet to look like glass. so much so others should wonder how i bent glass into the odd shape shown in the pics posted by planet 10 (dave).
i know i am still far away from painting or polishing it but i would like to ask for ideas.
i want the cabinet to look like glass. so much so others should wonder how i bent glass into the odd shape shown in the pics posted by planet 10 (dave).
Many things....
First, cute kid navin!!
Second. glad to hear things are working out for you, Rob. (Especially with getting the cracks fixed) When I read about your cracks, and how small they were, a thought that came to mind would have been to hit it with a dremel instead of a router. (I assume they're in the U.K. as well, if not, its basically a very tiny hand held router)
As to the finishes, I can offer some advice to both of you.
First, navin, for a mirror glass look, you're talking a LOT of hard work. Its also difficult to do by hand. The mirror finishes you see are sprayed lacquer. If you don't have spraying equipment, it becomes more difficult. I don't remember who, but someone on this board has posted a link to a website that gives an explanation of a way to do it by hand. (Do a search in the loudspeaker forum for finishes)
Second, Rob. Rob, did the person who recommended the French Polish technique give you an idea of how much work that is going to be? Also, are you aware that shellac can be easily damaged by alcohol? (even when "dry") Don't get me wrong, its a great finish, and finishing medium that I've used on several occasions, its just not a great durable finish. Depending on the veneer you used and what you're looking for in a finish, I can recommend some over finishes/techniques that won't be as time consuming/difficult. Things that come to mind include using Tung Oil (it gives a great touchable finish, but yellows pale woods slightly)
If you want a great looking finish be prepared to spend some time on it. Don't rush it. For me, when I'm building furniture, I allocate at least a week for a good finish. Lots of sanding and multiple coats. A good place to get information on finishes would be to check out Homestead Finishing. This is run by one of the top finishing guys in the U.S. (I know you're both outside the U.S., but he also has a forum, and will answer questions as well)
I'm really looking forward to seeing pictures of the finished cabinets! I'm hoping to be starting some cabinets of my own soon! (I'll be using some of the ideas from both of you guys)
First, cute kid navin!!
Second. glad to hear things are working out for you, Rob. (Especially with getting the cracks fixed) When I read about your cracks, and how small they were, a thought that came to mind would have been to hit it with a dremel instead of a router. (I assume they're in the U.K. as well, if not, its basically a very tiny hand held router)
As to the finishes, I can offer some advice to both of you.
First, navin, for a mirror glass look, you're talking a LOT of hard work. Its also difficult to do by hand. The mirror finishes you see are sprayed lacquer. If you don't have spraying equipment, it becomes more difficult. I don't remember who, but someone on this board has posted a link to a website that gives an explanation of a way to do it by hand. (Do a search in the loudspeaker forum for finishes)
Second, Rob. Rob, did the person who recommended the French Polish technique give you an idea of how much work that is going to be? Also, are you aware that shellac can be easily damaged by alcohol? (even when "dry") Don't get me wrong, its a great finish, and finishing medium that I've used on several occasions, its just not a great durable finish. Depending on the veneer you used and what you're looking for in a finish, I can recommend some over finishes/techniques that won't be as time consuming/difficult. Things that come to mind include using Tung Oil (it gives a great touchable finish, but yellows pale woods slightly)
If you want a great looking finish be prepared to spend some time on it. Don't rush it. For me, when I'm building furniture, I allocate at least a week for a good finish. Lots of sanding and multiple coats. A good place to get information on finishes would be to check out Homestead Finishing. This is run by one of the top finishing guys in the U.S. (I know you're both outside the U.S., but he also has a forum, and will answer questions as well)
I'm really looking forward to seeing pictures of the finished cabinets! I'm hoping to be starting some cabinets of my own soon! (I'll be using some of the ideas from both of you guys)
I contacted homestead last year and Jeff sent me
an email on how to get the piano black finish.
here is what he said;
This is all with the Fuhr Products and others we sell.
1. Glue size all machined edges.
2. Apply 2-3 coats 9500 primer, sanding between coats. Sand final 600 grit.
3. Apply 2-3 coats Fuhr 9100 series black paint
4. Sand final coat no finer than 800 grit.
5. Apply 3 coats 375 Acrylic varnish, when dry, level sand, until no
imperfections are in finish. Touch up if necessary at this point
6. Apply 3-4 more coats, allow to dry 1 week. Then buff out to desired sheen
using Menzerna polishing products and a buffer with lambswool or foam pad.
Jeff
an email on how to get the piano black finish.
here is what he said;
This is all with the Fuhr Products and others we sell.
1. Glue size all machined edges.
2. Apply 2-3 coats 9500 primer, sanding between coats. Sand final 600 grit.
3. Apply 2-3 coats Fuhr 9100 series black paint
4. Sand final coat no finer than 800 grit.
5. Apply 3 coats 375 Acrylic varnish, when dry, level sand, until no
imperfections are in finish. Touch up if necessary at this point
6. Apply 3-4 more coats, allow to dry 1 week. Then buff out to desired sheen
using Menzerna polishing products and a buffer with lambswool or foam pad.
Jeff
Hi Jeff, Shaef, Navin.
Thanks for all the interest shown. I've been away for a few days and it was nice to get back and find these posts.
Navin - I got a quote from a "man down the road" at an automotive shop who does this work. The price is for cash, in his lunch break etc...and it wasn't too bad.(not much more than the cost of me purchasing spray paint and laquer and sandpaper etc)
I'm got to admit that I'm pretty crap at finishing stuff, and I'll usually take the easiest route [ie: the one even I could make look fairly ok ]
Schaef- I had originally planned on varnishing the cabs, but was recommended the shellac as I posted before.Yep we do get the dremmel stuff over here too! I asked at work but no-one had one to borrow. I used a cordless angle grinder and a chisel to clean off the glue and rough up for the fibreglass/resin. btw the veneer is american black walnut.
I'm going to resin/fibreglass the ok cab on Monday, and I should have both ready for finishing by next weekend. I'll let you know what happens as and when..
Cheers
Rob
Thanks for all the interest shown. I've been away for a few days and it was nice to get back and find these posts.
Navin - I got a quote from a "man down the road" at an automotive shop who does this work. The price is for cash, in his lunch break etc...and it wasn't too bad.(not much more than the cost of me purchasing spray paint and laquer and sandpaper etc)
I'm got to admit that I'm pretty crap at finishing stuff, and I'll usually take the easiest route [ie: the one even I could make look fairly ok
]Schaef- I had originally planned on varnishing the cabs, but was recommended the shellac as I posted before.Yep we do get the dremmel stuff over here too! I asked at work but no-one had one to borrow. I used a cordless angle grinder and a chisel to clean off the glue and rough up for the fibreglass/resin. btw the veneer is american black walnut.
I'm going to resin/fibreglass the ok cab on Monday, and I should have both ready for finishing by next weekend. I'll let you know what happens as and when..
Cheers
Rob
thanks for the tips Schaef/thylantyr. I am going to print this out as reference.
i can rent a compressor and spray gun. so that wont be a problem. I think I will ask a professional polishman to do this (for a fee).
I saw a pair of speakers and sub from Definitive over the weekend. the Sub had 2 passive radiators and the sats had a side mounted woofer. The sats sell for US$600 per pair (in Rupee terms) and the sub for about $1200 each. They had the kind of finish I am aiming at. black and glossy. very glossy.
i can rent a compressor and spray gun. so that wont be a problem. I think I will ask a professional polishman to do this (for a fee).
I saw a pair of speakers and sub from Definitive over the weekend. the Sub had 2 passive radiators and the sats had a side mounted woofer. The sats sell for US$600 per pair (in Rupee terms) and the sub for about $1200 each. They had the kind of finish I am aiming at. black and glossy. very glossy.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.