Rounding over curved sides

[Wend]

Hi folks,

I'd like to round over the top edges of this softwood:

I have an arris roundover router bit, and if it simply had straight sides, then I think the long edges would be no problem with a couple of push sticks on the router table, and the short edges would probably also be OK with the mitre fence on the router table.

However, with the curved ends, I'm less sure. I'm not convinced I could make a decent job of it holding the wood freehand on the router table, and I'm not sure how safe it would be either.

Looking at videos on youtube, I think many people would use a microjig grr-ripper on the router table. I think that both quality and safety would be better, but I'm unsure whether either would be adequate.

I feel like my best bet would be the Katsu hand-held router, with the work piece held in the vice. Presumably I'd want to start in the middle of one of the long sides and then just try to go all the way round.

Does that seem like the best bet?

I'll also probably want to do the same with this bit of ash:

except I'm not sure I can hold this in the vice sensibly. Perhaps best would be to clamp one end down to the bench, do the other end with the Katsu, and then move the clamp to do the other half?

Does that sound reasonable?


Thanks for any advice!

 

[Trevanion]

I would've just done it all freehand on the router table. I assume your arris bit is only around 3mm in radius, so that won't really cause any kickback or tear out and you won't have any safety issues so long as you keep your hands away from the bit. Your workpieces are large enough to have a good grip on with your hands and perform the task without any special aid. But that's just my opinion and if you don't feel comfortable enough to do that, please don't.

The other ways you've specified about using a katsu router and clamping the pieces would be the absolute safest way to go.

 

[Phil Pascoe]

A hot melt glue gun is your friend.

 

[Wend]

A hot melt glue gun is your friend.

Forgive my ignorance, but what would I be gluing to what?

 

[Phil Pascoe]

Pieces like your bit of ash - just tack it down to your bench, do the work and peel it off again.

 

[Wend]

Pieces like your bit of ash - just tack it down to your bench, do the work and peel it off again.

Ah, thanks! I've never used hot melt glue, but I'm intrigued by glue that can resist the force a router throws at it, but which can then just be peeled off!

So now that's a microjig and a glue gun on the Christmas wishlist...the only problem being that I'm trying to make pre-Christmas decorations with them

 

[Phil Pascoe]

101-uses-for-a-hot-melt-glue-gun-t100646.html

A few ideas for you.

 

[Tasky]

Silly question, but could you not just grab a spokeshave or something and do it by hand?
Bung it in the vice and set to..... Take you 10 minutes, maybe?

Or have I missed something?

 

[Nelsun]

The Veritas cornering kit things would do the first bit pictured but not more intricate internal curves like the later one. They're enjoyable to just pick up and use (you'd have a hard time drawing blood with them!). But, like a router, you have to watch grain direction. That said, it's easy (and wise) enough to use the smaller sizes and build up to the final roundover to get a feel for grain direction. They're not the cheapest but well worth it when you need them.

https://www.axminster.co.uk/veritas-cor ... kit-510441

 

[Adam9453]

Providing it’s a bearing guided router bit then I’d personally prefer to do it freehand in the router table at home as it keeps the piece flat on the table so makes the job easier. If you’re not comfortable with the router option then just sand the corners off to a small radius, or you could use a file, rasp, spokeshave. There quickest is the router but you need to be comfortable you can do it safely as they chomp bits out of you very quickly if the wood gets thrown and you end up putting your hand in the bit, plus it happens at lightning speed when it does go wrong.
Do you know someone nearby to you that’s more experienced so could show you how to do it safely?

 

[AndyT]

Silly question, but could you not just grab a spokeshave or something and do it by hand?
Bung it in the vice and set to..... Take you 10 minutes, maybe?

Or have I missed something?

I agree with Tasky.
A router bit won't get into those narrow corners but a small penknife will.
Or if you don't like that idea, glue sandpaper onto a lolly stick and use that.

 

[custard]

I'm with Andy/Tasky. There's loads that can go wrong using a roundover bit in a router. The router references off the workpiece, so if the workpiece isn't dead square and true the, the roundover runs in and out accordingly.

Also setting up a roundover bit accurately isn't all that easy, Wealden make a superb range of roundover bits with a two degree lead-in angle, but I doubt you'll be using one of those.

You'll be far better off doing the job with hand tools. Incidentally, for a roundover that rolls around onto end grain I generally use a fine file, that is the recommended practise at the Barnsley Workshops.

 

[user22161]

they chomp bits out of you very quickly if the wood gets thrown and you end up putting your hand in the bit, plus it happens at lightning speed when it does go wrong

I can vouch for that! I now have a gripper but it hides small items so can't see what the cutter is doing. Double sided tape to hold pieces down on the bench is an alternative to glue and using the Katsu should be fine.

 

[Wend]

Thanks everyone for the advice! I'm flattered that you think I could do a decent job with a spoke shave, but I have my doubts!

I decided to set it up on the router table to see how it felt, and trying it out with a test piece it was a lot less dramatic than I expected. I guess the much smaller cutting area, compared to when I've been making grooves in the past, means there's a lot less force going on.

Anyway, with the help of the lead-on pin and guard above the blade, I rounded over the corners of the first piece, and also made a base for it to sit on and rounded over that too:

and finished:

The second piece I haven't managed to finish shaping yet, so it might get deferred to next Christmas. Although if I can get it done in the next month or two then it can be put away with the rest of the ornaments, so I'll keep at it!

I think it might be easier to do this with a grr-ripper or similar, to more easily be able to apply force in all the required directions. I guess this would mean not using the top guard, as it'll get in the grr-ripper's way, although the shape of the piece is such that the fence would need to be so far back that the guard would probably be useless anyway.


Thanks again!

 

[Inspector]

Wend it is good that you are asking about procedures that you are unsure of.

I would be comfortable routing the tree in one pass without any holding aids but you should know that you can do the job or many others with larger radii safely by taking multiple passes, starting with the bit partially retracted at first and raising it a little for each pass until you are cutting the full profile. So try a piece of scrap at 1/2 depth, raise it to 3/4 and then take a final pass at full. With experience you'll find out how much you can cut each time with different woods. This one might be good with two passes and a 3/4" radius might be better with four or five passes. Keep the wood between you and the bit and whatever is not cuttable with the bit can be hand sanded.

Pete