Routing a precision 'ledge' for GG in mahogany, which bit type?
I am starting work on a 14x17 conversion back for Deardorff S11. I need to rout a ledge or groove for the GG to the correct ANSI depth of 0.320 +/-
0.016. Setting the correct depth will be simple once I set up, but I am not a real woodworker. I have done work like this in metal on a mill.
What sort of bit is used?
What is the cheapest type of router to use?
I say cheapest, as this tool will have one purpose, this job, perhaps once.
I may rout the ledge in the 4 pieces first and then build the GG holder.
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
Hi Randy,
The challenge I see is that the .320" dimension is from the face of the wood to the face of the ground glass, which
is the side opposite the side you're cutting.
You need to set a reference surface on the vise within the open section of the back that projects up by the proper distance, then
touch off the face of your cutting tool to that reference. This assumes the work is sitting flat on the vise base.
The standard solution would be to build a stack of gage blocks.
You can get router bits that have non-cutting ends, to control the horizontal depth of cut.
Fancy ones have a small ball bearing on the nose; cheap ones just have a cylindrical steel projection.
The diameter of the cutter is determined by the required horizontal depth.
I would cut out the corners with a drill so they don't challenge the router bit.
This is not an issue if you cut the four pieces before assembling them.
- Leigh
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
Leigh, I know you are a machinist.
I understand machinist methods, and it is the best way, but if I have a known dimension or height, I can cut from above, down to that T distance #.
I don't consider 0.304 - 0.336" range to be a difficult target to achieve with crude setup. A flat table and flat wood clamped to it can be tried a few times until I reach the correct bottom face to GG spec.
I do wish I had that granite surface block they threw away at work. :(
Trial and failure will give me experience. But I don't know which $30 bit and cheap router to buy. I looked at Home Depot. :) I imagine I will not need a very powerful router as the cut will be shallow and not wide.
Basicly T distance is 5/16". I have flat milled and sanded 1/2" wood. I need to remove 3/16" down and 3/16" wide to create the GG ledge.
My 1/2" stock right now is 0.504. I'm going to let it set a while and adjust to my RH. Then I will sand it to darn close to 0.500"
I have way more time than money in my early retirement. I can experiment.
This guy is a bit of inspiration, but I am only making a back. I have holders and camera.
http://vimeo.com/28160586
Quote:
Originally Posted by
Leigh
The challenge I see is that the .320" dimension is from the face of the wood to the face of the ground glass, which
is the side opposite the side you're cutting.
You need to set a reference surface on the vise within the open section of the back that projects up by the proper distance, then
touch off the face of your cutting tool to that reference. This assumes the work is sitting flat on the vise base.
The standard solution would be to build a stack of gage blocks.
- Leigh
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
For hard woods, specifically Padauk, I often use carbide end mills designed for aluminum, I get the ones that have been re-sharpened so many times that they are no longer useful for the aviation industry here in Montreal. I find I get better results with these than with cheap router bits from Home Depot, and for less money. I've tried doing this sort of thing with a Dremel tool and the Dremel 'router table', but they're far too flimsy to get proper results. You need a solid cast iron or cast aluminum shaper table, with proper jigs, if you want repeatable results with proper tolerances. I'm afraid these aren't cheap.
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
I do have a few mills, never thought of using them on this. My toy mill, a Unimat is a hassle to set up for anything bigger than a coin
This is really a new project, I figure midwinter before it really gets moving.
Back to plumbing the sinks...
Quote:
Originally Posted by
Jody_S
For hard woods, specifically Padauk, I often use carbide end mills designed for aluminum, I get the ones that have been re-sharpened so many times that they are no longer useful for the aviation industry here in Montreal. I find I get better results with these than with cheap router bits from Home Depot, and for less money. I've tried doing this sort of thing with a Dremel tool and the Dremel 'router table', but they're far too flimsy to get proper results. You need a solid cast iron or cast aluminum shaper table, with proper jigs, if you want repeatable results with proper tolerances. I'm afraid these aren't cheap.
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
A router table with a fence would be the ticket for what you want to do.
You can cobble a table together out of MDF.
I did most of my light routing with a Ryobi laminate trimmer mounted upside down on a piece of MDF
before getting a router table. For a one off this may work for you.
I've ordered and used their carbide tipped bits for making lens boards -
http://www.mlcswoodworking.com/shops..._straight.html
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
Thanks guys, I think a trim router will do it, of course I will need to fiddle with depth and cut.
I made a boat once just to learn how wood is used.
I know I can do this. I spent years watching and helping my brother obsess with his custom woodwork business until it put him down. He's alive, but barely. If he would crawl out to his shop he could make a damn nice camera. That's not happening.
When I make something, I will show it here.
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
Google videos of DIY router tables. You'll get some good ideas on how to throw a cheap one together.
A plunge router would make things easier, as you can change the depth easily with these.
Have you considered hiring a router?
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
I just spent a while looking this up.
I prefer DIY, as I get it done. Hiring is usually a bad idea for me, I should always just buy the tool and learn to use it.
I miss my factory mechanic job as we could do anything in that factory, we were a million square feet of DIY, every function under one roof.
Retirement is both Hell and Heaven.
Quote:
Originally Posted by
Lachlan 717
Google videos of DIY router tables. You'll get some good ideas on how to throw a cheap one together.
A plunge router would make things easier, as you can change the depth easily with these.
Have you considered hiring a router?
Re: Routing a precision 'ledge' for GG in mahogany, which bit type?
After you screw it up once, it'll be much easier the second time around! :)