Measuring Flat Angles on Ply?

[MalcolmA]

Very Basic Question Here, So much so, I almost feel silly asking it. But after spending about 2 hours hunting and asking in hardware stores yesterday, I am no better informed.

I'm at the stage of marking intersecting panels etc on the sides of my Tuba 36, and i'm struggling with the angles.

Due to the large size of the project, I don't really want to rely on a standard 5cm radius protractor to measure, as I would imagine any minor inaccuracy would be quite a long way off once you get to the other end of the board.

I suppose i'm either looking for an oversized protractor, or perhaps a tool designed especially for drawing angles, (i imagine it would look like a ruler, with a hinge in the middle, that shows how many degrees angle between the 2 parts.

I'm amazed I have'nt been able to find a tool to help,
If you guys know of anything, or have another method your help would be much appreciated.

I have considered Sin, Cos, and Tan trig, but wrote that idea off pretty soon after I remembered what my final year Maths exams results were.


THanks In Advance,
Malcolm

[Lawrence Langford]

I would suggest using a sliding bevel to transfer the angles from the ply to your table saw. They only cost a couple bucks, but are invaluable for the job.

http://www.rd.com/content/openContent.d ... ntId=12940

[CBIERN]

Here's what I use but you still have to translate the result to set the proper blade angle on your saw.

http://woodworker.com/cgi-bin/FULLPRES. ... UM=897-877

[Les Webb]

One of these is what most carpenters use.

http://cgi.ebay.com/SWANSON-PROFESSIONA ... dZViewItem

[bgavin]

I would suggest using a sliding bevel to transfer the angles from the ply to your table saw. They only cost a couple bucks, but are invaluable for the job.

http://www.rd.com/content/openContent.d ... ntId=12940

I use exactly the same tool. You get the angle into the tool, and hold it on the bed of your table saw. Adjust the blade to match the tool until you don't see daylight. Works every time.

[MalcolmA]

Oh, Sorry I may have put you wrong there... I've Cut the sides to size but nothing else yet, and I'm still actually trying to draw the angles out on the ply, so I know where to drill holes etc for the internal panels that make up the horn itself,

Would you guys usually use a small protractor when initially marking out the ply?

[MalcolmA]

quote]http://woodworker.com/cgi-bin/FULLPRES. ... UM=897-877[/quote]

Oh silly me, yes the link above is exactly what i am after, just as i imagined it would be, Thankyou very much, have printed that page out.

Off to see if I can hunt one down locally now,

[telecast]

These work really well too. They're extremely accurate.
http://www.harborfreight.com/cpi/ctaf/d ... umber=4185

[Bill Fitzmaurice]

I'm at the stage of marking intersecting panels etc on the sides of my Tuba 36, and i'm struggling with the angles.

The angles are all shown in the plans, unless your copy is more than 4 months old.

[Lawrence Langford]

I'm at the stage of marking intersecting panels etc on the sides of my Tuba 36, and i'm struggling with the angles.

The angles are all shown in the plans, unless your copy is more than 4 months old.

My copy is. hint,hint

[Les Webb]

I think there may be a little confusion here. After re-reading your post it seems to me that you are trying to draw the layout lines using the angles provided in the plans. Big no-no.

Just use the given measurements and connect the dots.

The angles given in the plans are there to help with the bevel cuts on the horn plates.


Maybe I'm the one confused but if this is what you are trying to do it will only lead to frustration and a tuba that is laid out incorrectly.

Les

[Lawrence Langford]

I think there may be a little confusion here. After re-reading your post it seems to me that you are trying to draw the layout lines using the angles provided in the plans. Big no-no.

Just use the given measurements and connect the dots.

The angles given in the plans are there to help with the bevel cuts on the horn plates.


Maybe I'm the one confused but if this is what you are trying to do it will only lead to frustration and a tuba that is laid out incorrectly.

Les

I think that is exactly whats happening.

[taiguy]

in agreeance with larry and les. sounds like the problem is getting started with the layout on the side boards.

the measurements are all there, plot the dots, and then draw the lines connecting them with a straight edge. i'm pretty sure i revisited a fair share of middle school geometry while drawing out the tuba plans.

[MalcolmA]

Thanks Guys

Thanks, Lawrence & Les's etc understanding was correct, and thanks for that advice. So instead I will try just plotting the points and joining dots as you have advised.

Thanks Again,
Malcolm

[Bill Fitzmaurice]

Thanks Guys
So instead I will try just plotting the points and joining dots as you have advised.

That's what you're supposed to do. The angle figure is provided so that you don't have to measure them yourself to know what angles to cut the panel ends at.