Last of the GR Research builds - 5.1 kit

[bibin3210]

Never use Iron Nails on MDF, they will pop out (1 or 2 mm) after few years and spoil the finish.

Use only glue (Fevicol SH) or glue along with self tapping screws.

Thanks,
Bibin

 

[omishra]

Wow. So treat started.
Captain, keep it on.

 

[keith_correa]

I expected this question but wanted to cross the bridge when it comes.

The surface after sawing can never be as smooth as the one that is planed or routed and hence not only the adhesion would be suboptimalbut even the fit may not be airtight. The bigger the saw, the rougher would be the surface area resulting from the cut. By sacrificing 1mm they achieve far superior adhesion with the glue and ensure airtight fit.

Smooth does not equate to optimal adhesion. A little rough is better, IMO, as long as the surfaces align and they are adequately clamped after gluing up. And, with MDF [which I assume you're using] with what I've seen, cuts using a power saw are more than adequately smooth. I wish I had a picture to upload here to show how smooth but I didn't take any the last time during a build. As far as I know [with what was told to me by the guy who builds them for me] the sharpness of the saw is everything so if their cut surfaces are not smooth it's time for them to change the blade. Also, using a circular saw, the guy who builds them for me ALWAYS tells me that the size will be +- 2mm from what I've given. He gives a damn about being precise because he feels that it does not matter but if he really applies his mind to it he can get the level of precision needed. All he needs to do is take into account the thickness of the blade but he could care less.

But all this is OT. Carry on please.

 

[venki7744]

Never use Iron Nails on MDF, they will pop out (1 or 2 mm) after few years and spoil the finish.

Use only glue (Fevicol SH) or glue along with self tapping screws.

Thanks,
Bibin

Is this true for Glue with Nails?:sad: I Switched from screws to Brad nails recently. What I thought was the nails/Screws are only for adhesion till the glue dries after that the panels stay together due to the strength of glue. I have seen people removing screws after drying and filling the hole with wood filler (e.g. Hexbase (PWK) designs in youtube).

 

[bibin3210]

Is this true for Glue with Nails?:sad: I Switched from screws to Brad nails recently. What I thought was the nails/Screws are only for adhesion till the glue dries after that the panels stay together due to the strength of glue. I have seen people removing screws after drying and filling the hole with wood filler (e.g. Hexbase (PWK) designs in youtube).

No Nails at all on MDF. You can remove the screws once the glue is dry. If you have enough F-Clamps to hold the panels together, there is no need for screws as well.

 

[keith_correa]

Never use Iron Nails on MDF, they will pop out (1 or 2 mm) after few years and spoil the finish.

Why would they pop out?

 

[bibin3210]

Why would they pop out?

MDF basically splits or chips when you nail into it with no holding power as it has a layered internal structure.

 

[venki7744]

MDF basically splits or chips when you nail into it with no holding power as it has a layered internal structure.

Does it split even if I use 18G brad nails, I didn't notice any splitting. I am using a pneumatic Nailer to push these through.

Rajesh Sire, if you feel that this conversation is hijacking your thread please feel free to ask mods to move this to a separate thread.

Thanks,
Venki

 

[keith_correa]

MDF basically splits or chips when you nail into it with no holding power.

No it does not. At least not if done right and if the MDF is of good quality and thick enough. Plywood gets the way you described but again - not ALL plywood exhibits this behavior.

as it has a layered internal structure.

Not!!! Plywood has layers and carpenters use nails all the time on it.

 

[magma]

Never use Iron Nails on MDF, they will pop out (1 or 2 mm) after few years and spoil the finish.

Use only glue (Fevicol SH) or glue along with self tapping screws.

Thanks,
Bibin

correct

No Nails at all on MDF. You can remove the screws once the glue is dry. If you have enough F-Clamps to hold the panels together, there is no need for screws as well.

MDF basically splits or chips when you nail into it with no holding power as it has a layered internal structure.

absolute correct!!!

bibin you forgot the part about the bloody lambi and paint shrinkage issue when you use nails OR screws
especially when you do water buffing DUCO

 

[bibin3210]

No it does not. At least not if done right and if the MDF is of good quality and thick enough. Plywood gets the way you described but again - not ALL plywood exhibits this behavior.

Not!!! Plywood has layers and carpenters use nails all the time on it.

I disagree with your statements. I know many of the carpenters here use nails on MDF, there are carpenters they even use screws on multi wood. Basically they are not formally/technically trained to use these new generation wood substitutes. Most of them treat it the same way they deal with natural wood. In-fact there are special screws available for MDF, not sure about the availability in India.

Please go through the Wiki page also pasting it here for easy reference :
https://en.wikipedia.org/wiki/Medium-density_fibreboard

"MDF may be glued, doweled or laminated. Typical fasteners are T-nuts and pan-head machine screws.[6] Smooth-shank nails do not hold well, and neither do fine-pitch screws, especially in the edge. Special screws are available with a coarse thread pitch, but sheet-metal screws also work well. Like natural wood, MDF may split when woodscrews are installed without pilot holes."

 

[turgid]

Given this not so convenient nature of natural wood and MDF, why not use stronger, easily workable and more cost-efficient alternatives like Good Wood which is a homogeneous synthetic resin sheet that feels and sounds just like MDF. Available in multiple thicknesses and easier to maintain.... once painted looks just like wood too!

Advantages of goodwood panels over traditional wooden panels in areas such as carpentry, furniture making, office furnitures, panels, constructions

 

[keith_correa]

Please go through the Wiki page also pasting it here for easy reference :
https://en.wikipedia.org/wiki/Medium-density_fibreboard

"MDF may be glued, doweled or laminated. Typical fasteners are T-nuts and pan-head machine screws.[6] Smooth-shank nails do not hold well, and neither do fine-pitch screws, especially in the edge. Special screws are available with a coarse thread pitch, but sheet-metal screws also work well. Like natural wood, MDF may split when woodscrews are installed without pilot holes."

My last post on this in this thread so as not to derail it: What the wiki page says is absolutely correct but you have to see the context. They are referring to using nails to HOLD MDF together whereas where I'm coming from is towards using nails [the really thin ones] just for holding it in place post gluing. I've got furniture at home which is made of MDF using this method and it's been 5+ years now - not one bulge anywhere. For additional strength at the edges, the carpenter also drilled pilot/guide holes and at intervals inserted regular wood screws along the edges. The screw heads were counter sunk and a mixture of MDF sawdust and diluted Fevicol used to fill the holes.

I've also seen carpenters NOT glue edges together on furniture but only use lots of really nails on MDF and they too DO NOT protrude an mm or so after 1 - 2 years.

THAT was what I disagreed to and posted against.

 

[regeHA]

Yup... That's what we need.

A bunch of guys arguing about MDF, nails, glue and what not.

Please take the discussion elsewhere guys and let us enjoy the pics.

 

[venki7744]

The rear side (Note the slot on the top portion of the depression for wall mounting)

Sire, can I make a suggestion, instead of these connectors, use Binding post that can be screwed through the box wall or a Speakon connector. These types of connectors (again binding post in a plastic base) might affect the sealed system.

Sorry one more OT (this is the last one I promise hyeah, this is the nail that I use

 

[quad]

Yup... That's what we need.

A bunch of guys arguing about MDF, nails, glue and what not.

Please take the discussion elsewhere guys and let us enjoy the pics.

It is actually an informative discussion, and the members
involved are knowledgeable. As long as the discussion remains on
target and no tempers frayed, it is educational. and relevant to
DIY speaker builds.
Perhaps they can split it off to a separate thread.

 

[keith_correa]

Given this not so convenient nature of natural wood and MDF, why not use stronger, easily workable and more cost-efficient alternatives like Good Wood which is a homogeneous synthetic resin sheet that feels and sounds just like MDF. Available in multiple thicknesses and easier to maintain.... once painted looks just like wood too!

Advantages of goodwood panels over traditional wooden panels in areas such as carpentry, furniture making, office furnitures, panels, constructions

Is it really cost effective as compared to MDF? In what way - material cost? I checked the website - would make an excellent alternative to MDF.

 

[bibin3210]

The Baffle (This would be facing the ceiling)

Checking the fit of drivers

The side view

My last post on this in this thread so as not to derail it: What the wiki page says is absolutely correct but you have to see the context. They are referring to using nails to HOLD MDF together whereas where I'm coming from is towards using nails [the really thin ones] just for holding it in place post gluing. I've got furniture at home which is made of MDF using this method and it's been 5+ years now - not one bulge anywhere. For additional strength at the edges, the carpenter also drilled pilot/guide holes and at intervals inserted regular wood screws along the edges. The screw heads were counter sunk and a mixture of MDF sawdust and diluted Fevicol used to fill the holes.

I've also seen carpenters NOT glue edges together on furniture but only use lots of really nails on MDF and they too DO NOT protrude an mm or so after 1 - 2 years.

THAT was what I disagreed to and posted against.

I was mentioning about the nails used in the above images.

Is it really cost effective as compared to MDF? In what way - material cost? I checked the website - would make an excellent alternative to MDF.

This is not suited for speaker enclosures much lighter than MDF, cost around 4.5K for 18mm 4ft x6ft sheet.

Thanks,
Bibin

 

[quad]

Given this not so convenient nature of natural wood and MDF, why not use stronger, easily workable and more cost-efficient alternatives like Good Wood which is a homogeneous synthetic resin sheet that feels and sounds just like MDF. Available in multiple thicknesses and easier to maintain.... once painted looks just like wood too!

It may not be desirable in this application where non-homogeneous
constrained layer damping etc have advantages.

Lowering Mechanical Noise Floor in Speakers Pt 2 | Audioholics

A Whitepaper: The Audibility Of Cabinet Panel Resonances and Pat. Pend. Method Of Reduction Of Audible Coloration - Dagogo | A Unique Audiophile Experience

 

[omishra]

As I already mentioned in another thread of my build, I used strong wooden toothpicks. But not hammered them forcefully. Drilled hole with exact size of toothpick, around 2.5mm diameter and 2" length where plugging done. Then I filled this hole with fevicol and lightly hammered strong toothpicks in each hole at a time. I saw Carpenter working with wooden plugs to make join internally stronger. It was done at each 4" on edge. This way I ensured keeping iron nails away.