Finalists questions

[Avalanche]

I have a few additional questions:
- Will the plate with the jacks seal well enough?
- Where should I place the crossovers?
- The pvc tubes are 1mm too long, what's the recommended way to trim them precisely?
- Why did one builder cover the mid port?

Since I had to redo two panels it ended costing me more to order them than buy the rotor...

[Jim Holtz]

I have a few additional questions:
- Will the plate with the jacks seal well enough?
- Where should I place the crossovers?
- The pvc tubes are 1mm too long, what's the recommended way to trim them precisely?
- Why did one builder cover the mid port?

Since I had to redo two panels it ended costing me more to order them than buy the rotor...

The plates should be sealed to the cabinet with window or door insulation, rope caulk or something similar.

I placed my crossovers in the bottom of the cabinet and secured them with a wood screw to hold the crossover board in place.

If it were me, I'd either cut or sand the extra 1mm off and then glue it to the MDF

The switch in the binding post plate is there to allow close wall placement by plugging the mid tube in back and flipping the switch to provide the correct balance when close to the wall behind the speaker.

HTH

Jim

[Avalanche]

Thanks for the answers Jim.
There's already rubber gasket on the lips of the plate as in the drivers but I'm not sure they seal well enough on the mdf.
I understand about the close wall placement but why seal it altogether?

I took a picture of the inner front baffle over the redone outer front baffle. It's hard for me to guess how rigid it will be when glued. Is it good enough with this size difference?

[Jim Holtz]

I can't answer why anyone would want to seal the mid when it's made to switch between closed mids and open back so easily. I much prefer open back but I designed these to work in my room.

I think you'll have enough MDF to hold the drivers securely. I like the double thickness but it'll be fine.

If there's a gasket on the binding post plate, that's all you need.

Jim

EDIT: Use Jim Holtz Finalist.pdf for better cabinet plans.

[Avalanche]

I made a mock with the same thickness mdf boards and it failed (you can see the crack). I drilled holes first, applied glue, screwed in 5cm long screws, then put on it a weight overnight. What did I do wrong, should I use shorter screws?

[Jim Holtz]

My suggestion, don't use screws. Clamps will provide the strongest joint. I use a brad nailer to hold the panels position and then clamp securely.

There are others that are much, much better cabinet makers than I so hopefully they'll jump in with advice.

Jim

[Avalanche]

EDIT: - I tried a different method for using screws which failed as well so screws are out of the question. Since clamps are pretty pricy and I already invested more than I planned, what's the min. number of clamps necessary for completing the entire assembly?
- Shall I place the crossovers below the foam?
I plan to use wax to cover the mdf from inside. For finish I think I'll use enmale paint and polish it for gloss.


There's nothing much to say about the crossovers except they seem to be working.



It may be unnecessary but I'm looking for a way seal any small openings that may be around the jacks and switch:

[Steve Manning]

My suggestion, don't use screws. Clamps will provide the strongest joint. I use a brad nailer to hold the panels position and then clamp securely.

There are others that are much, much better cabinet makers than I so hopefully they'll jump in with advice.

Jim

I agree with Jim, with mdf stay away from the screws in the edges. I would suggest either biscuits or using dado's, they work very well for alignment and additional joint strength. Either option you can put the entire box together for a "dry" fit before you add any glue or clamps.

Steve

[Avalanche]

How would biscuits help? I need a way to press the pieces together anyway.
I can't use a dado because I don't have any special carpentering tools.

[knowledgebass]

Biscuits help by providing positive assistance in positioning during glue-up, making joints less likely to slip out of alignment, a change in grain direction through the joint, and increased surface area for glue to adhere to. The last two points increase the joint strength. Biscuits require a specialised tool or router adapter to install. I used a combination of biscuits and dados in my ongoing build and can pick up my 34"x10"x15" cabinets with just two clamps applied across the width. It's also made it possible to do the glue-up in one go but I'm using 14 clamps and could have used more.

[Steve Manning]

How would biscuits help? I need a way to press the pieces together anyway.
I can't use a dado because I don't have any special carpentering tools.

knowledgebass just summed it up nicely. Here is the build I finished up this past summer, https://www.htguide.com/forum/showth...sen-1071-Build, lots of biscuits in this one and there's some pictures in there of a cabinet all put together with no clamps at all. Not only do the biscuits help align the joint but the friction in the pocket helps it from coming apart. Yes, you would have to get a biscuit joiner but they are not too expensive these days and if you can find a gently used one there a good option to add to your tool kit. Besides I thought you had to buy at least one new tool during a project build, I'm sure it's a rule.

Steve

[Carl V]

http://www.mcfeelys.com/product/JSS-0001/3-D-Square-Precision-Aluminum-Clamping-Corner

http://www.woodcraft.com/category/4/1001028/1004032/corner%20clamps.aspx

http://www.woodcraft.com/category/3/1005233/1001028/Clamps.aspx

Look at the 3d Corner clamps.


See if you can find something you can both use & afford form these links.

The trouble with DIY is the hidden costs. People look at the basic parts list
and often times over look the tools required. DYI is fun but it can be more
expensive than you might at first thought. Which is why PE cabinets are so
nice & handy.

[impala454]

knowledgebass just summed it up nicely. Here is the build I finished up this past summer, https://www.htguide.com/forum/showth...sen-1071-Build, lots of biscuits in this one and there's some pictures in there of a cabinet all put together with no clamps at all. Not only do the biscuits help align the joint but the friction in the pocket helps it from coming apart. Yes, you would have to get a biscuit joiner but they are not too expensive these days and if you can find a gently used one there a good option to add to your tool kit. Besides I thought you had to buy at least one new tool during a project build, I'm sure it's a rule.

Steve

Awesome build! Love the attention to detail!

[Avalanche]

Will gluing with clams in many steps work too? I'm trying to find an easy and affordable way to go on with the assembly... Instead of using biscuits I'm thinking about using straps around the assembly to help it keep aligned. I made marks where the clamps will be placed.

[Avalanche]

Lastly:

[knowledgebass]

Yes, that is certainly workable. Consider using some corner/'L' brackets with some hand spring clamps to assist you with holding it all square as you tighten the clamps. You can buy specialty ones for wood working, but shelving L-brackets should work just fine if you verify them with a carpenter's square.

[Avalanche]

I made a little more progress and so far it looks a lot less refined than I hoped. I manually filed around the driver holes to maximize airflow. Now I wonder whether I should proceed with the current panel or get a router and make a new one: 1. is the manually filed no-so-symmetrical bevel good enough as it is? Is the partial gap in the gasket a good reason to make a new one?

[Avalanche]

I started gluing each part separately, let's see how it works out...

[Jim Holtz]

The bevels look fine to me. They're on the inside so they don't have to be pretty.

Jim

[Avalanche]

I glued some further today. I saved $100 on clamps but now I see it'll make the work harder than I'd thought since the parts won't match perfectly and I'll have to file them to match despite my attempts to align them as best as I could...

[Avalanche]

I tried to glue these parts as aligned as possible. Now I'm not sure what to do about the tiny gaps...

[Jim Holtz]

Silicon bathroom caulk works great to fill very small gaps. There are a whole bunch of sealers/glues at the home stores that can be used inside the cabinet to seal things up. If you have a gap on the outside of the cabinet, I prefer auto body filler for a permanent repair that has strength to it. Wood filler for tiny outside gaps.

Jim

[TEK]

That's quite a common problem. It's darn hard to get those panels to the exact right size...

Those gap are so small that it might be enough to just fill with wood glue. If you do not think that is enough you could also mix MDF saw dust with wood glue and use that to fill the gaps. Be sure to get it pressed as long as possible inside the gap. It will be as strong as the MDF and it will also bind to both the MDF plates and give a very strong joint. This is my preferred method to fill gaps like that.

[Avalanche]

I'm not worried about the air seal, I'm worried about how I'm supposed to glue the panels to a strong box without a close fit. I'll try to file some material off the left side panel where the brace is protruding (L), but how am I supposed to make a strong joint between the right side panel and the brace with the small gap (R)? The only ways I can think of are either using a cement like material for filling, or removing material from the joint with the front panel (marked in violet). Remember I don't have any precise carpentry tools.

[TEK]

MDF is quite easy to shape.
Sandpaper (60) on a hard, plain, surface is well suited to fine tune and adjust according to need, and is quite cheep.
If you still have gap you could fill it using MDF dust and wooden glue as mentioned before.

[Carl V]

http://www.alibaba.com/showroom/concave-molding.html

Scotia White MDF molding. Glue this on the inside, does two
things seals up that gap & provides for joint reinforcement.

You could also use 1/4" or 1/2" solid wood Square stock.
Achieve same end. Seals & reinforces...sorta like Corner blocks.

I have used this technique when I had no access to Dado blades
& I wanted nice & strong Internal braces

[Avalanche]

Carl V, I fail to see how gluing these will make it nearly as firm and strong as gluing the mdf panels directly to each other... filing off material by hand to make it fit could be a lot of work and not very accurate so I'd rather do it additively. What and how can i glue or mold to the panel to make a joint as strong as if it was part of the original panel?

[Carl V]

in addition to gluing the MDF sides to one another....not instead of or in lieu of.
There have been times that after gluing up a box, you may find a gap or air leak
for whatever reason. The method I mentioned will help to solve that mishap.
Managing the occasional mistake is all part of the fun of DIY.

Yes, of course sanding the high~spots will also work. A little troublesome. But
you find that afterwards you box is no longer perfectly square. Not a deal breaker.

[Avalanche]

I glued one side panel after sanding some excess mdf. We'll see how that worked...

Now how will it work for the small 2mm gap to sandwich glue that skinny unidentified panel between the mdf panels for filling?

[Avalanche]

I glued the bottom panel...

[Avalanche]

And the result...





Could be better I suppose but not bad for hand work.

Looks like I didn't pay enough attention to details and should have removed the excess glue to make it a tighter fit:

[Avalanche]

What should I do before I glue the last panel? Should I glue the internal wires?
How can I seal all the tiny cracks air may leak through?

[TEK]

First you fill the visible cracks with one of the methods described in the previous replies.
When thats done and everything looks OK you can use silicon or tec7 on all edges inside your box to ensure that they are air thight.