Which way should angles be cut?

[Sanitary sound]

Hi all, We are beginning a dr200 build.

Can anyone clear this up; when the plans show an angled cut using a bent arrow how do I know which way the angle is supposed to "face"?

I've cut the throat horn sides with the leading and trailing edges parallel (which makes sense) but the arrows in the plans seem to be telling me that that is wrong. Also the description says that both the edges should face the same direction which would mean that one edge would not be flush to the baffle board.

This is probably really simple but I now have doubt and can't find any information about woodworking diagram standards.

Cheers. Tom

[Harley]

Can anyone clear this up; when the plans show an angled cut using a bent arrow how do I know which way the angle is supposed to "face"?

:iitp:

The leading and trailing edges are cut at a 9 degree angle, both facing the same direction. Keeping in mind the flare of the horn write on them which face is inside the horn. Cut the remaining edges at 7 degrees, the blade angled so that the inside face is the wider. Draw center lines on the throat horn sides, on the inside and outside.

Also, here's the most valuable piece of information you get with your plans; Your Sketchup model is an invaluable tool. With it you can view every part from every conceivable vantage point, even from inside the cabinet. Use the tutorial to learn how to use the program.

and can't find any information about woodworking diagram standards.

There aren't any specifically for woodworking, but technical drawings normally follow engineering draughting codes of practice, of which Bill's plans sometimes do...and sometimes don't.

You have to read his plans through carefully and thoroughly several times - all the information you need is there when accompanied by using Sketchup

[Sanitary sound]

The Sketchup model seems to say different from the plan. It suggests that the leading and trailing edges are parallel. Leading edge attached to the baffle board trailing edge attached to the supports. these boards are parallel so the edges of the throat horn sides should be too. however the plan seems to suggest that I cut like this:



Which does not make sense to me....

[Harley]

Which does not make sense to me....

Of course it wouldn't because you've got both angles facing opposing directions!

btw - please ammend your post above by removing the dimensioned sketch of the side, otherwise your post will get culled. Putting plan details out on the forum is

[Sanitary sound]

Shouldn't it look like this?

[Harley]

Shouldn't it look like this?

That's confusing me now, and seems far from right.

Please use your Sketchup model and btw see my post above about removing the plan of the side from your insert.

Can't help you any further - I'm off to work

[Sanitary sound]

Which does not make sense to me....

Of course it wouldn't because you've got both angles facing opposing directions!
:

I disagree. the face of the angle is surely the side it faces. I.e. the side you can see it from. If anyone can clear this up I'd appreciate it. the plan says to mark on which side is inside the horn but doesn't say if the side diagrammed is supposed to be inside or outside. The throat horn support is also confusing me. Am I supposed to assume that the measurement given is always of the longest side once the board is cut?

[David Carter]

Sounds like the issue here is what is meant by which way an angle "faces." Since this is causing confusion, ignore the wording, and follow the sketchup model. It is correct. I think of it this way... these pieces you are cutting have two edges that are parallel to each other and two that aren't. On the edges that are parallel to each other, the angles are such that the faces of those edges should be parallel to each other. On the edges that are not parallel to each other, the faces are not parallel to each other either. They are flared so that the piece is wider on the side that will be facing the inside of the horn throat. Hope that makes sense. If you look ahead in the plans a few steps to see how everything fits together to form the horn throat, it should make more sense.

If you take a minute to dissect the sketchup model, there will be no doubts. All will be clear.

[Sanitary sound]

Ok thanks guys. I'm going to check all of the measurements against the sketchup model from now on. It seems the angle sign (bent arrow) is only being used to show when there are angled cuts not which way the angles are supposed to be cut. I'm also going to assume that the measurements from the sketchup model are more correct as I have found an instance when the dimensions in the plan are not coherent with the model. Sorry I'm nit-picking I just hate wasting wood!

I'm really looking forward to getting these loaded up and playing out! Its a wicked looking design!

[Harley]

I disagree. the face of the angle is surely the side it faces.

In trig as well as any form of draughting, here's how it works in pictorial form;



You could also say that in the top article, the angles are facing in converging directions for that particular side of the article. On the left hand side of the top article, it would be diverging directions.

Thanks for blocking off those dimensions

[Sanitary sound]

Cool. That makes sense now! Thanks

[Harley]

Cool. That makes sense now! Thanks

You're welcome.

[DrDoug018]

Cool. That makes sense now! Thanks

If it makes you feel any better, I had exactly the same question but wasn't as deliberate as you and went ahead and made the wrong cuts. I interpreted the "angles facing the same direction" the same way you did. I tried to figure it out via sketchup but didn't know (at the time) how to explode that part of the model so I couldn't see any angles. Finally, in my plans (I'm building the DR250) it said that "This figure, and all figures where there are angled cuts, shows the wider face of the part" but for this piece the top edge is actually the narrower edge. If you look very closely at the diagram you can perhaps see that top edge angle but my printed version (and my old eyes) weren't clear enough to catch that.

So, I botched up the first horn throat and had to start over. No big deal but not a very auspicious way to start this complicated build. Things have gone much better since and I am about 2/3 of the way through two cabs. Still have to make one @#$%^&* melded array but even that gets better with practice.

These things are complicated though. I say a prayer to the PL god once a day.

Doug