Best method of making accurate bevels.

[MikeG.]

Mike was correct in his assumptions that the originals were painted but I am trying to avoid that if I can hence the pursuit of good bevels.

In which case poplar isn't a great choice of timber. Poplar generally is for painting only, at least in better work.

 

[simonms]

Sure, it is however a good choice for sound qaulity in this particular application and also what was used originally.

I know poplar is not known for it's alluring beauty but again, I am somewhat hemmed in regarding materials choice.

 

[Jacob]

Mike was correct in his assumptions that the originals were painted but I am trying to avoid that if I can hence the pursuit of good bevels.

Painted is utterly different. There would almost certainly have been no effort to match bevels - they all would have been square planed all round, glued over a former, gaps filled, shaped, remaining gaps filled, painted. The narrow laths would make this easier as the difference at the edges would be reduced.
If you want nice looking wood then it's a different game altogether. You wouldn't use poplar for a start (boring and dull) unless veneered instead of painted. Solid wood different again.
You really need to saw stuff and smash it to bits to find out how its made!

 

[simonms]

I could see the joins through the paint quite clearly and there didn't seem to be any signs of filling but you might well be correct. I think it might be asking a lot on the first run to get things perfect so the fall back is to paint it but I would like to try.

I have re drawn the curve to what I understand might be a good way of approaching this from all the advice given.

So the first slat will start the curve with a 90 degree cut, the adjoining slat will have the face joining the first slat beveled but the opposite edge will again be at 90 degrees and so on. Here are some pictures, one of the complete cross section and another of a typical slat.

If I am right in my understanding the bevels would need to be carefully planed in offering up to check as you go over a former.

 

[simonms]

The curve.

 

[OscarG]

If you do end up painting it, could you not create a template of the entire curved shape then using that template with a router (on say 1 inch thick stock) make 39 identical curved sections and glue them all together to make one big curved wall that's a 1m high?

 

[simonms]

I see what you mean Oscar and did try that out of interest with plywood and locating dowels for each component, it was not 100% successful but perfectly passable. The issue I have is that I must adhere to the original methods of building but as Jacob has pointed out short of sawing an original to bits I have to do a bit of educated guess work and although the methods I am proposing with the last pictures might not be exactly as it was done in the past I think it would be fine as it's not a million miles away and I like the idea of being slightly more precise in the methodology.

 

[Derek Cohen (Perth Oz)]

I do not understand what is so difficult at jointing 89 degrees. I do it all the time when I aim for 90 !

Seriously, create a 1 degree shim for a flat shooting board, lay the work piece on that, and joint the edge.

Regards from Perth

Derek

 

[woodbloke66]

Seriously, create a 1 degree shim for a flat shooting board, lay the work piece on that, and joint the edge.

Regards from Perth

Derek

Simples works :lol: - Rob

 

[custard]

Here's the problem with the shim on the shooting board idea. You'd still have to check that the plane's lateral lever is correctly positioned. So why not get rid of the shim entirely and simply set the 1.5 degree bevel angle using the lateral lever in the first place?

 

[Derek Cohen (Perth Oz)]

Custard, as you are aware (is this the beginning of senior moments? ), the lateral lever is only used to square the blade. A canted blade can wreck a shooting board.

A shim should be reliable. I would use one of those digital angle gauge boxes on top of the work piece to check the angle is consistent.

Regards from Perth

Derek

 

[Jacob]

..... A canted blade can wreck a shooting board.

In that case you need to make a better shooting board. A canted blade is exceptionally useful on a shooting board or off it.

A shim should be reliable. I would use one of those digital angle gauge boxes on top of the work piece to check the angle is consistent.

Regards from Perth

Derek

I wouldn't bother at all about consistency - if you look at the OPs drawings the angle are all going to be sightly different. I'd bother about how each piece fits against the previous one. Don't measure/gauge anything - just look at the fit.
No need for digital gadgets when you've got eyes. :lol:

 

[Derek Cohen (Perth Oz)]

..... A canted blade can wreck a shooting board.

In that case you need to make a better shooting board. A canted blade is exceptionally useful on a shooting board or off it.

A shim should be reliable. I would use one of those digital angle gauge boxes on top of the work piece to check the angle is consistent.

Regards from Perth

Derek

I wouldn't bother at all about consistency - if you look at the OPs drawings the angle are all going to be sightly different. I'd bother about how each piece fits against the previous one. Don't measure/gauge anything - just look at the fit.
No need for digital gadgets when you've got eyes. :lol:

Jacob, really?

The only time you want to cant a blade on a shooting board is to square it to the side of a out-of-square shooting plane.

Consistency is everything. You can even be skewed ... as long as mating pieces are consistent with this, such as when match planing.

I do not expect perfection, but I aim for it. If you do not aim for accuracy, what do you end up with? :shock:

Anyway, I do not believe that you mean any of this - you are deliberately being obtuse.

Regards from Perth

Derek

 

[simonms]

Thanks for the continued discussion, much appreciated. I am just about to have a trial run at a few methods and see if I can turn my hand to this and just wanted to check how people feel about my methods shown in the drawings of leaving a 90 degree angle on one side of the piece and beveling the other and so on to create the curve. My intentions are to give this some practice and continue to post with any issues I might run into. I'll be making up my shooting board next week.

 

[AndyT]

There's a tiny issue in that the two edges won't match - the bevelled one will be slightly wider than the square one - so there will be a little step at the join. But in practice you should have enough spare thickness left in the wood for this not to matter. I'm assuming you will be planing everything to a fair curve, not leaving it as a set of flat facets.

 

[simonms]

Thanks Andy, yes, thats the idea. I was thinking that leaving the 90 degree bevels would halve the amount of work and leave some fairing but the reality of this process is an unknown to me. I am going to have to carefully consider my starting widths.

 

[Jacob]

..... Maybe after dry fitting for good joins I might remove them beforehand.

Nope.
The whole point of "fairing in" or finishing after something has been put together is that errors occur during the process of joining. If you try to finish before you just get a different set of things to "fair in" and lose more thickness in the process.

 

[Jacob]

.....The only time you want to cant a blade on a shooting board is to square it to the side of a out-of-square shooting plane.

Unless you want to undercut it as per our OP - often done anyway to get a nice tight join on the visible face. You can do it in the vice, not only on a shooting board

...
Anyway, I do not believe that you mean any of this - you are deliberately being obtuse. ...

Moi? No certainly not!
Our OP won't find out how to do it until he starts and if he's lucky he will start using his eyes. If he's really unlucky he'll become bogged down with "precise methodology" , precision gadgets and be endlessly trying to square the circle.

 

[simonms]

Ok, so plane bevels as I go to fit and once I am happy with that part glue up in stages and then fair.

This will be a learning curve (boom boom) for me so I won't treat the first attempt like the final job more of a matter of seeing how this particular method works in reality then adapt it if I need to but I want to draw on experience to get off on the right foot. This thread has probably saved me a few mistakes so far.

 

[Jacob]

Ok, so plane bevels as I go to fit and once I am happy with that part glue up in stages and then fair.

Yep. Mark them as you go so they go back in the right order. Perhaps pencil numbers at one end or something.
In the old days it would have been done with hot glue so you'd fit and glue each piece one at a time, not needing cramps. Not needing very precise bevels either as glue would fill space.
Trad methods are a lot easier.

I am going to have to carefully consider my starting widths.

Too much thinking! You already settled on 63mm why not just go for it?