Routing suggestions

[sucramuk]

Hi all

I want to construct the attached.
It will made up of around 15 - 16 separate sections of 18mm ply.

I have had templates cncéd for the shape already, my production process is:

1. Mount template to first ply piece
2. Use flush bit to trim ply to size, rough cut shape already
3 . Remove template
4. Mount machined ply to next ply piece
5. Back to step 2

Is it worth me building a router table for the flush cutting as opposed to trying to balance router on a small surface area, all being well I will be producing a few of them 10's maybes 100's,if it works out.

Will it be safer option to use top mounted flush cutter.

Thanks

 

[marcros]

i would look at (subcontracting out) cncing the shapes. for production of 10's or 100's, you have the quantity to make it efficiently. probably cheaper than your labour.

 

[pcb1962]

I would get a quote for CNC'ing them before going any further.

 

[sucramuk]

I agree, but its in its infancy.

I have a couple of 2000w routers at the workshop

Also if the pieces are premachined. I then have to ensure they all line up exactly.

 

[SkinnyB]

I would recommend a router table. Not only is it a large area to balance the work. It will eliminate any chance you may tilt the router and leave a mark on your finished piece. You can also extract the dust and chips better. As your pieces have straight edges you would be able to bring you fence in close with a extractor hooked up and possible below.

I do this thing quite a lot and prefer doing it on the table.
http://skinnerdesigns.blogspot.co.uk/20 ... q=template
Hope that helps.

 

[sunnybob]

How are you cutting the middle out?
If you are planning on removing all that ply with just a router bit, you should order in a stock as they will gum up and overheat from the adhesive inside the ply.

without a cnc it would best to remove almost all of the internal with a large forstner bit or even a jigsaw, and most of the external on a bandsaw. leaving just a final finishing cut with the router.

 

[sucramuk]

Hi

Yes intended to use jigsaw to cut out as much as possible, just hopefully clean up with the router.

 

[morturn]

Am I understanding you correctly?

Are suggesting you flush trim the first piece with the template, then use the first piece as the template for the next, and so on?

If you do that you will multiply any error by two on each successive step.

If I was doing this I would certainly make up a router table. Does not have to be a complex building, just a flat piece of plywood with the router bolted underneath it.

There is a guy on You Tube who makes some quite impressive boxes with the simplest of router tables. Cannot recall his name, but a search may find him

 

[sunnybob]

Just remember that if you are cutting an inside shape on a router table you go the opposite way round!

If you dont youll get a lot of splintering.

 

[sucramuk]

Just remember that if you are cutting an inside shape on a router table you go the opposite way round!

If you dont youll get a lot of splintering.

So move workpiece left to right then for inside pieces?

 

[sunnybob]

work out which way the cutting edge rotates in relation to direction of cutting.
For example, on a table you move the wood right to left to cut accurately. If you move the wood left to right it will snatch and maybe even throw the wood across the room.

If you are cutting inside a shape the direction of travel should be reversed. i have a diagram somewhere but cant find it at the moment.

 

[sunnybob]

Cant find the really simple one, but this article will explain direction of cut.
http://www.kregtool.com/files/newslette ... ary14.html

 

[sucramuk]

I'm thinking about this, my flush bit has bearing top and bottom, so if I flip the workpiece over then i can travel all pieces right to left?


I will have to be careful in the internal corners as there will be a tendency for the ply to grab?

 

[LancsRick]

I'd sing the virtues of a router table and advise you to get one purely because of useful they are. If for some reason you don't want to, then how about fixing a board to the router baseplate, and securing it upside down securely. For the area you're working on then that might work as a makeshift table. If you do this, ensure beyond a shadow of a doubt that the router is secure.

 

[sucramuk]

I decided to buy a router table on Friday, I thought it will get some use.

Attached are images based on advice Im being told, am I correct in workpiece direction?
(arrow points to direction workpiece will move)

Want to be clear as cutting tomorrow morning.

Also I agree if I need to make a fair amount these then I will get the pre flush cut shapes cnced.

 

[LancsRick]

Not quite. I assume the diagram is top down. Therefore the cutter will be rotating counter clockwise as you look at your diagram. If you are cutting at the 12oclock side of the cutter you should be moving the workpiece left to right on your diagram. If cutting on the 6oclock side, moving right to left.

The mental check to do is that you should be pushing INTO the cutter edge as it comes towards you. If it's the other way, the cutter will grab the piece and pull it with its direction of travel. Which will give you noise, a broken workpiece, and an adrenaline hit. Shorter fingers too if you don't let go of the workpiece.

 

[sunnybob]

those are the correct directions assuming you are using a table and viewing from above.
If not, take a few seconds to look at the cutter blade. the blade has to pushing into the cut, not bouncing along from behind the cutting edge.

 

[sucramuk]

Thanks guys.

So pending if I'm cutting at 6 or 12 oclock will determine direction.

There is no issue cutting either side whilst using a table?

Also as said I have a flush cutter with bearing top and bottom, should i cut with workpiece on bed with template on top contouring on top bearing? This to me seems safer as there will less cutter protruding through router bed.

 

[sunnybob]

forget about the bearings. direction of cut is determined SOLELY on the blade attacking the wood as it rotates, rather than the blade hitting the wood backwards.

Direction of cut is NOT 6 or 12 oclock, its internal or external.

 

[sucramuk]

So I done the project today.

A few niggles.

The burn marks, I guess I need to move the piece quicker, sometimes difficult when trimming the external and internal corners..

I managed to get zero gouges so the process of mounting new piece and flush cutting against previous piece worked.

One thing, the piece grew by about 2mm over the 16 pieces, I guess the router could not have been cutting perfectly square.

Now suggestions on how to mount to wall, don't really want to just put coach bolt through solid backing piece, suggestions please. It need to carry the weight of the build plus a bike 10 -15kgs.

Many thanks.