Help Sawdust Makers

[i386]

I'm building a cabinet to house an amplifier I recently built. The box turned out nicely. Working on the front and back of the box now.

I need to make some 3/4" diameter inside cuts in plywood as shown in this picture.

http://thunderboltamps.com/newcabs/P1010232 mini 5 front 2 .jpg

It needs to be as close to perfect as possible because I'll be running a roundover bit around it.

Freehand with a hand jigsaw looked really bad.

Next attempt was to drill the corners with a 3/4 paddle bit. Better, but not good enough.

I may need some new tools...

Clamp a fence in a drill press and use a hole saw?
Router w/straight bit and circle template?

 

[woosterken]

Re: Help Sawdust Makers

round over bit? it is made up of many sheets how you going to round over that?
I think I would use a hole saw before you make the cut out

woosterken

 

[i386]

Re: Help Sawdust Makers

round over bit? it is made up of many sheets how you going to round over that?
I think I would use a hole saw before you make the cut out

woosterken

Forgot to mention it'll be covered in tweed. The plans call for 1/2" plywood on the front and 1/2" roundover. Will look something like this when complete...

 

[Moody Blue]

Re: Help Sawdust Makers

Forstner bit or hole saw the corners first then complete the cutout with table saw or ???

 

[Bass Man Bruce]

Re: Help Sawdust Makers

My 2 cents.
Cut the corners with a forstner bit as mentioned, then jig saw the straight cuts with 1/8" to 1/4" to spare.
Then clamp a straight edge where you want the straight cuts and use a router with a bearing guided flush cut bit on it.

 

[i386]

Re: Help Sawdust Makers

My 2 cents.
Cut the corners with a forstner bit as mentioned, then jig saw the straight cuts with 1/8" to 1/4" to spare.
Then clamp a straight edge where you want the straight cuts and use a router with a bearing guided flush cut bit on it.

That sounds like a plan!

Thanks everyone.

 

[Tim Frank]

Re: Help Sawdust Makers

My 2 cents.
Cut the corners with a forstner bit as mentioned, then jig saw the straight cuts with 1/8" to 1/4" to spare.
Then clamp a straight edge where you want the straight cuts and use a router with a bearing guided flush cut bit on it.

How many ways are there to skin a cat?....

If you have a bandsaw and a 1/2" blade, I think you could make the "jigsaw" cuts with a guide board and skip the step with the router and trimming down to on-size. The bandsaw cuts should be more than OK especially if you are covering with cloth.
Mind you, if you have to change blades, you are going to use any time saved from skipping that step....

 

[i386]

Re: Help Sawdust Makers

Many ways I think...

The only good non-hand tool I have is a 12" Delta chop saw which is a great tool but not much help here. I purchased a decent Craftsman bench top 10" drill press (it's no Delta) and a set of forstner bits. I will give that approach a try. Been wanting a drill press for a while anyway.

Another way I heard today was just to clamp a homeade square guide in there and cut the whole thing with a router.

 

[itsaboattime]

Re: Help Sawdust Makers

Dude, take it from a carpenter, the hole saw is the way to go. Then clamp a straight edge to the stock to use as a fence. then run your Jig saw along the straight edge/fence. Its not a race, dont push hard on the saw. too much pushing is what binds the blade and causes it to "wander", causing an ugly cut.

Forstner bits are intended for solid material, not laminates like your plywood.

 

[i386]

Re: Help Sawdust Makers

Here's this evening's attempt using the new drill press and jigsaw w/straight edge...

Larger pic here. Click the magnifying glass for even larger. We'll see how well it takes the roundover bit. These cabinet fronts are traditionally made with baltic birch plywood which is much better that what I'm using. If it doesn't work I've got a little solid pine left.

BTW, the hardware came in today. Genuine Fender nickel plated corners and a leather strap. Also not pictured are some nice rubber feet for the bottom.

Full sized pic here.

The tweed and cane covering should arrive tomorrow. They'll look something like this.

 

[Bass Man Bruce]

Re: Help Sawdust Makers

Way to go, looks good!
We're now expecting you to sound like Santana!

 

[itsaboattime]

Re: Help Sawdust Makers

Now, before you hit it with a router, use a wood rasp to take any saw kerfs out of the cut. The smoother your cut the better the roundover will look. A little bit of time spent dressing up the cut will give better results with the finished product.

 

[i386]

Re: Help Sawdust Makers

More progress...

Almost ready for covering.

 

[ThumbPkr]

Re: Help Sawdust Makers

Sure is purty!!Congratulations on your progress and thank you for sharing with us.Ron G

 

[i386]

Re: Help Sawdust Makers

Almost done guys. Just need a few more finishing touches before I have the faceplates made...