Print Page | Close Window

cutting plywood the smart way

Printed From: Speakerplans.com
Category: Plans
Forum Name: 1850 and 186 horns
Forum Description: Discussion / Questions about the 1850 and 186 horns
URL: https://forum.speakerplans.com/forum_posts.asp?TID=107782
Printed Date: 26 March 2026 at 5:35pm
Software Version: Web Wiz Forums 12.08 - https://www.webwizforums.com


Topic: cutting plywood the smart way
Posted By: BrainlessTekno
Subject: cutting plywood the smart way
Date Posted: 22 March 2023 at 11:40am
Hi,
im building 186 horns and i wonder if there is the "right way" to cut the wood,
for example i can cut the pieces without angles and then i can cut the angles after.
Or i can cut angles right from the start and do just one cut to make 2 angles at once. 

It is my first time building a speaker with angles different then 90 degrees and im not realy sure how to go with it. Also i would realy appreciate stylesheets, hacks or solutions to upcomming problems if u know some. Take in mind i cant afford fancy stuff like CNC 



Replies:
Posted By: BrainlessTekno
Date Posted: 22 March 2023 at 12:11pm
Also there is a lot of old questions with pictures that are no longer avalaible so if someone have them it would be amazing if they post them here


Posted By: eyeT
Date Posted: 22 March 2023 at 1:52pm
It really depends how your woodworking skills are but cutting the angles as you go, if you can do it accurately, saves a bit of time and a bit of material.
Here's a link to a cut-list online app. which may be of help to you.


Posted By: eyeT
Date Posted: 22 March 2023 at 1:53pm
https://cutlistoptimizer.com/" rel="nofollow - https://cutlistoptimizer.com/




Posted By: bob4
Date Posted: 22 March 2023 at 6:34pm
Was looking at the 1850 vs 186 plans, they seem very similar in a lot of measurements, except the panels that make up the rear wall of the horn path, adjacent to the rear chamber..... they seem a couple mm's off. And obviously the 1850 chamber is smaller. For the boards in the front size and oriemtation appear to be identical, so the angles can be taken from the 1850s design page. How about the other angles? What are the differences 1850 vs 186?

I'm sure it has been answered a million times, but maybe some veteran SP user can chime in? 

I'd advise to carefully consider where to cut the angles, and minimize their amount. It's easier to join if you cut an angle on only one of the two board edges, and leave the other one straight. 

Basic common sense tips: 
- don't rush anything
- measure more than once, check, recheck, mark, check again before cutting
- make sure you have enough offcuts/scraps to do test cuts until you have your table saw or track saw dialed in 
- make sure your tablesaw fence is perfectly parallel to the blade! 
- having the panels 5-15 mm oversize allows for enough clearance for a clean cut. If the board doesnt have excess, the sawblade will have to score/scrape the edge of the board, which is not good, and might pinch the blade and cause problems
- if the cut is not straight, it is near impossible to fix it by running again through the table saw
- at the risk of sending you down another rabbit hole, the best way to shape and fine-tune the angled edge is a handplane. With it you can take away very tiny amounts of material and straighten wobbly edges. Requires practice andto learn and get into though. For hand plane tips check rex krueger and paul sellers on youtube
- best practice would be to rebate the boards of the horn path into the side walls -> use a router, and to dry-fit without glue and screws. If the box goes together properly and square you can go ahead with glued assembly
- rebates help keeping everything aligned during assembly
- precision is neccesary, otherwise the cab could have gaps between boards, be out of square etc. I've been involved in enough speaker cabinet building that ended up in desperate efforts to force things into their place. 
- i'd probably rebate all the braces as well. Makes the fitting process also more forgiving, since the edge of the brace doesnt need to fit 100% to the face of the board if it sits in a rebate





Posted By: BrainlessTekno
Date Posted: 23 March 2023 at 8:00am
Thanks i will try to do it with jist one angle where pieces stick, I will buy nailgun for this project, do you have experience with this tool ? Should i go for some more expensive ones or is the basic one good (is there a big difference in quality) ??


Posted By: Father-Francis
Date Posted: 23 March 2023 at 12:01pm
With the nailguns all depends, is it a one time use you want to use for other stuff or only speakers, I would buy a small cheap one that runs on air ( compressor) easy to use there’s a whole lot of them out there , but that’s just me , look at one like this , I got one too , good but can’t get it to shoot some area cause it’s too big ,  https://www.toolstation.com/dewalt-dcn662-18v-xr-16g-straight-cordless-brushless-nailer/p51042" rel="nofollow - https://www.toolstation.com/dewalt-dcn662-18v-xr-16g-straight-cordless-brushless-nailer/p51042
https://www.toolstation.com/power-tools/nail-guns/c48" rel="nofollow - https://www.toolstation.com/power-tools/nail-guns/c48
Loki for the smallest you can get and make sure it can nail from 25mm up to 64mmnail 16g is fine . Hope that gives you an idea


-------------
Music is the strongest form of magic.(+45 31879997)blakmanpro@gmail.com, foa@sweetboxaudio.dk


Posted By: snowflake
Date Posted: 23 March 2023 at 1:24pm
nailgun is good if you want to work fast but if you are starting out you might find clamps and screws easier to deal with. 50mm self tapping screws with a 20mm shank. some sort of drill guide is useful until you get confident doing it by eye:
http://www.amazon.co.uk/Woodworking-Locator-Adjustable-Template-Drilling/dp/B099WNZNXW?source=ps-sl-shoppingads-lpcontext&ref_=fplfs&smid=A1ZPGB68LT4P5N&th=1" rel="nofollow - https://www.amazon.co.uk/Woodworking-Locator-Adjustable-Template-Drilling/dp/B099WNZNXW?source=ps-sl-shoppingads-lpcontext&ref_=fplfs&smid=A1ZPGB68LT4P5N&th=1

corner clamps are useful to get the outside of the box square:
http://www.amazon.co.uk/Multi-Angle-Suitable-Woodworking-Drilling-Cabinet/dp/B08F5F457F/ref=sr_1_8?keywords=corner+clamp&qid=1679577492&sr=8-8" rel="nofollow - https://www.amazon.co.uk/Multi-Angle-Suitable-Woodworking-Drilling-Cabinet/dp/B08F5F457F/ref=sr_1_8?keywords=corner+clamp&qid=1679577492&sr=8-8

check all your diagonals are equal and adjust before gluing anything - if you start off with a wonky box fitting the internals will be a nightmare.

personally when cutting two pieces for a joint I make the angles on each the same - that way you can cut them both in one go with no wastage. and the area of wood joining the two is maximised.

get a sharp saw blade and keep the rpm as low as possible to keep it sharp.


Posted By: imageoven
Date Posted: 23 March 2023 at 9:13pm
screws are easier to take out if you don't get it perfect first time.

I cut the most difficult angles first then remeasure the board and cut the 2nd, easier angle at the correct distance from the first.

A very easy mistake to make on boards with angles on opposing ends, is to cut at the correct angle but in the wrong direction, so I always mark up the board early on to show whether  the angles lean towards each other, or in the same direction and also which side has the critical measurement on.


-------------
Keep pushing on, things are gonna get better.


Posted By: bob4
Date Posted: 24 March 2023 at 8:38am
Clap good advice keeps pouring in......

Here's a good example of fully rebated construcion, note the assembly done without any fasteners, just clamps & ratchet straps!!! Shocked

http://croweaudio.blogspot.com/2013/01/b-sub-215-dual-15-project.html?m=1" rel="nofollow - http://croweaudio.blogspot.com/2013/01/b-sub-215-dual-15-project.html?m=1


Posted By: BrainlessTekno
Date Posted: 04 April 2023 at 10:41am
So i did the calculations and mange to create cutlist for 186 horn, i saw couple ppl looking for this so here u r (5mm thicknes of blade so there is no chance to mess it up by too wide saw) 

https://i.ibb.co/MsMYXDq/Sni-mka-obrazovky-2023-04-03-o-19-05-31.png" rel="nofollow - https://i.ibb.co/MsMYXDq/Sni-mka-obrazovky-2023-04-03-o-19-05-31.png

https://i.ibb.co/mt44D4R/Sni-mka-obrazovky-2023-04-03-o-19-05-18.png" rel="nofollow - https://i.ibb.co/mt44D4R/Sni-mka-obrazovky-2023-04-03-o-19-05-18.png

https://i.ibb.co/4tLLp2J/Sni-mka-obrazovky-2023-04-03-o-19-05-05.png" rel="nofollow - https://i.ibb.co/4tLLp2J/Sni-mka-obrazovky-2023-04-03-o-19-05-05.png

So u can fit 2 boxes on 3 panles 2500mm x 1250mm (there was a argument that u need 4) however you will need to be creative with back of the speaker chamber.


Posted By: cravings
Date Posted: 04 April 2023 at 3:57pm
plywood sheets are 2440 x 1220mm... you should still be ok but worth checking.


Posted By: woody2
Date Posted: 04 April 2023 at 8:43pm
Originally posted by cravings cravings wrote:

plywood sheets are 2440 x 1220mm... you should still be ok but worth checking.


Not always. 5000mm wide by any length is possible. Seems to be lots of 2400 x 1200mm around at the moment.


Posted By: Father-Francis
Date Posted: 05 April 2023 at 9:51am
Originally posted by cravings cravings wrote:

plywood sheets are 2440 x 1220mm... you should still be ok but worth checking.
where we buy they have them like this. thats in cm 
4 mm 152,5×305  
6,5 mm125×250152,5×305125×250152,5×305152,5×152,5250×125
9 mm125×250152,5×305125×250 250×125
12 mm125×250152,5×305125×250152,5×305
15 mm125×250152,5×305125×250152,5×305
18 mm125×250152,5×305125×250152,5×305 
21 mm125×250152,5×305125×250152,5×305 
24 mm 125×250152,5×305 125×250 152,5×305  
27 mm 125×250152,5×305 125×250 152,5×305 
30 mm 125×250152,5×305 


-------------
Music is the strongest form of magic.(+45 31879997)blakmanpro@gmail.com, foa@sweetboxaudio.dk


Posted By: BrainlessTekno
Date Posted: 05 April 2023 at 9:54am
well size of the ply depends on where you want to buy it, here in slovakia most of them are 1250x2500



Print Page | Close Window

Forum Software by Web Wiz Forums® version 12.08 - https://www.webwizforums.com
Copyright ©2001-2026 Web Wiz Ltd. - https://www.webwiz.net