There is nothing wrong with your first arrow. The line item cost merely reflects that you are purchasing two items each costing unit price. The handling charge includes shipping usually via a courier. The more you order the lower the charge gets.
Rapid are good, if they have the part and it's cheaper then use them.
Rapid are good, if they have the part and it's cheaper then use them.
wilmslow were a little more expensive and didn't have the exact component.
I have made the order with rapid now - came to around £10, a little expensive, but not too bad considering the fact that it is a vital component.
You said earlier that playing the woofer with just the inductors may cause damage - when I received it, I tested it for around 5 minutes on a low volume with this setup - it wont have been damaged in any way by this?
richie: thanks, and I didn't realise I had put 2 in.
I have made the order with rapid now - came to around £10, a little expensive, but not too bad considering the fact that it is a vital component.
You said earlier that playing the woofer with just the inductors may cause damage - when I received it, I tested it for around 5 minutes on a low volume with this setup - it wont have been damaged in any way by this?
richie: thanks, and I didn't realise I had put 2 in.
Reading the rest of the thread, if you inside-mount the woofer bear in mind you may not ever be able to get it out again without breaking the cabinet. Unless you are making a removable rear panel or something?
Also if you plan on undoing the driver mounting screws more than a couple of times I would not use wood screws as they will just end up pulling through the MDF, use machine screws and tee nuts. This may not be cosmetically ideal though if you do go ahead with the inside mounting.
Also if you plan on undoing the driver mounting screws more than a couple of times I would not use wood screws as they will just end up pulling through the MDF, use machine screws and tee nuts. This may not be cosmetically ideal though if you do go ahead with the inside mounting.
AndrewT said:
I disagree with this. The sub that was in the boot of my car whilst it rolled over at high speed and almost came out of the boot was not damaged in any way structurally. I only used butt joints, cut by hand as well.
Hi,
It was the capacitors I said might damage the amplifer, I assume you mean them not the inductor.
If you played it a low volume then it won't have done any harm at all. It is just that it puts a heavy load on the amplifer so if you played it loud it could damage it. If it still works its ok, it would have failed completely if it went. A well designed amplifer should be ok anyway its just not all amplifers are properly protected.
Regards,
Andrew
It was the capacitors I said might damage the amplifer, I assume you mean them not the inductor.
If you played it a low volume then it won't have done any harm at all. It is just that it puts a heavy load on the amplifer so if you played it loud it could damage it. If it still works its ok, it would have failed completely if it went. A well designed amplifer should be ok anyway its just not all amplifers are properly protected.
Regards,
Andrew
Surely once glued, I would have no access to the inside anyway? or is the purpose for using the nuts to allow modification until I am happy with it at which point it will be glued?richie00boy said:
Just wondering if its better to screw from the outside of the cabinet through the MDF and into the battens or:
screw through the battens and into the MDF.
I'm guessing that the first would be better as doing the opposite would mean that only a small amount of thread would be biting into the MDF (the batten is 21mm as opposed to the 18mm MDF.
I have been recommended to use no.8 1.5 (3.8cm) inch long screws.
38-21=17mm Screwing from the inside would give 17mm which would infact be the opposite of what I just thought. Would end up going too much into the MDF, leaving only 1mm spare and would probably break through, so I guess screwing from the outside is the only way to go, unless of course I get smaller screws.
How much thickness should remain between the outer wall of the MDF and the tip of the screw when screwing from the inside?
screw through the battens and into the MDF.
I'm guessing that the first would be better as doing the opposite would mean that only a small amount of thread would be biting into the MDF (the batten is 21mm as opposed to the 18mm MDF.
I have been recommended to use no.8 1.5 (3.8cm) inch long screws.
38-21=17mm Screwing from the inside would give 17mm which would infact be the opposite of what I just thought. Would end up going too much into the MDF, leaving only 1mm spare and would probably break through, so I guess screwing from the outside is the only way to go, unless of course I get smaller screws.
How much thickness should remain between the outer wall of the MDF and the tip of the screw when screwing from the inside?
When I used to cut boxes by hand I just drilled a pilot hole in the MDF and used 40mm panel pins into the end of the adjacent panel. Never had a problem. Just tap them down a bit using a punch then filler over the hole.
Have you got access to any bar clamps? I use these now and never nail or screw.
Have you got access to any bar clamps? I use these now and never nail or screw.
I'd rather use both the screws and the glue - I can use the no. 8 1.5 inch ones to screw the MDF at the corners, however, I think I will need shorter screws for the corner bracing.
Hi,
if 1.5inch is too long for the thicknesses you have selected then use 1.25inch.
If the tip of the screw gets too close to the surface of the MDF it does deform the surface and ultimately ruptures the surface with a crazed bump that does not look nice.
if 1.5inch is too long for the thicknesses you have selected then use 1.25inch.
If the tip of the screw gets too close to the surface of the MDF it does deform the surface and ultimately ruptures the surface with a crazed bump that does not look nice.
That is true Andrew, although I have rectified that in the past with the use of a file.
Just screw from the outside in and you won't have the problem anyway. The glue on it's own will be more than strong enough anyway, the screws will just help it hold in place while it dries. So they don't need to be mega gripping to the material.
Just screw from the outside in and you won't have the problem anyway. The glue on it's own will be more than strong enough anyway, the screws will just help it hold in place while it dries. So they don't need to be mega gripping to the material.
Presumably for the corner battens, I won't even need to use screws to hold them in - the glue should hold them well enough while they dry seeing as they sit in the corner?
Are you thinking of putting the battens in first to give you something to butt up against to make building easier? If not then I really don't think you even need battens. The corners are the strongest part of the box.
Well I intended to install them to just strengthen the corners to prevent any air loss. Also, they should help dampen any unwanted resonances across the MDF panel.
The corners don't need strengthening, they are the strongest point in the whole box. Unless I'm misunderstanding you - are you proposing to put the battens along the panel in the middle? That would help increase strength and reduce resonance.
Also unless your cutting skills are horrendous you should not have any leak issues, as long as you are not a total scrooge with the glue.
Just trying to save you extra effort and cost that really is not warranted 🙂
Also unless your cutting skills are horrendous you should not have any leak issues, as long as you are not a total scrooge with the glue.
Just trying to save you extra effort and cost that really is not warranted 🙂
So judging by what you are saying, the corner battens are completely pointless and a waste of time?
Yes exactly that. A total waste of materials and effort and box volume. Move them to the middle (or just off) on the panels to act as bracing there and they become worthwhile.
Try this little test. Find a basic box and rap your knuckles on the end of a panel by the corner. Now do it somewhere else on the panel and see how much more hollow and undamped it sounds.
The adjacent panel acts as a brace to the panel it's butting up against, so there is no need to add more bracing. Brace the middle (or just off) of the panel where it's at it's thinnest and most unsupported point.
Try this little test. Find a basic box and rap your knuckles on the end of a panel by the corner. Now do it somewhere else on the panel and see how much more hollow and undamped it sounds.
The adjacent panel acts as a brace to the panel it's butting up against, so there is no need to add more bracing. Brace the middle (or just off) of the panel where it's at it's thinnest and most unsupported point.
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