Sycamore 'sketch'

[Chris152]

I gave up on this effort a couple of weeks ago on account of my struggle with tearout - in this case I'm convinced it wasn't just me, it was the wood, too. Anyway, this morning I cut a slice out of it on the bandsaw (a table saw would be better but I don't have one) and reassembled it using a couple of nails with the heads sawn off.

It's very rough, the cut edges aren't parallel (easily sorted - I didn't notice til I looked at the photo) and much more of a problem is that the rim/ entire bowl doesn't quite line up:

It's tricky holding these bits in the vice for drilling on account of the rounded shape, and I can't use the drill press, so getting the holes going the right direction is hard. The top-to-bottom alignment should have worked as I lay the parts on the rim and used the nail points attached to one part to mark the other, but it clearly didn't - maybe because the nails weren't in straight.
Any suggestions on how I can get the drilled holes going in straight? I think I want to do more of these but don't want to chop up nicer bowls till I've got the hang of it.
Thanks
C
edit - maybe one of these? Might it work on a fairly narrow face?
https://www.axminster.co.uk/axminster-d ... gJrwfD_BwE

 

[nev]

one of these
https://www.youtube.com/watch?v=ZF8-JMMX_Wk

make a version at 90 degrees so your drill can slide across the bench and then just pack the jig or blank to get the desired height.

I'd also be tempted to cut the and drill the blank before you turn it. Glue it back together with paper between the pieces (or even use wooden dowels ) and then turn it, that way there are no issues with alignment.

 

[Sawdust=manglitter]

and I can't use the drill press

Hi Chris, when you say you cant use the drill press, do you have one that you could use? If so, what you could do is clamp 2 equally sized pieces of scrap to the top and bottom of the bowl which can then give you flat/parallel reference surfaces. Better yet if you cur the bowl with a flat surface, you could then put the bowl flat side down and clamp the scraps to it giving you a flat surface which should be exactly parallel to the bottom of your scraps, so should be exactly square then to the drill press. Did something similar myself a while back when drilling ashtray grooves...

 

[Chris152]

Thanks both. The problem with the drill press, even using your method S=M, is that there's not enough depth between the drill tip and the base to fit bowls into. That said, I looked at mine ( a small Draper) and wondered if it'd work if I remounted the upright and headstock rotated through 90 degrees, bolted it to the bench and used it over the side of the bench using your holding method and clamps to the side of the bench.
Meanwhile, I had a quick go at a variation of Nev's suggestion and that seems to work ok.

(I tried it on the slice I took from the bowl this morning.) As you say, doing it this way will allow me to place the bowl sections flat on their rims on the bench, so I might do a nicer version of that.
Nev - I didn't quite understand the second bit of your reply - if I cut, drill and re-glue with paper between, won't it fall apart when I turn it? Or how would the dowels work? Sorry to be slow... As it is, I think your suggestion for drilling should be fine.
Chris

 

[transatlantic]

These work well. Perhaps hot glue it on?

https://www.axminster.co.uk/axminster-d ... kit-210235

 

[nev]

Try it on a bit of scrap. Cut a slice out and use some PVA type wood glue like Titebond on all faces and slip some newspaper between the slices and clamp whilst drying. It should take a good whack or prising with a chisel to separate the pieces later.
The dowel suggestion - make some out of the same bit of wood, slice, drill, dowel and glue and then cut the dowels flush after separating - probably too much agro with hindsight.

 

[Ttrees]

Cool idea Chris

 

[Chris152]

Thanks all.
The paper trick sounds interesting, Nev - I'll keep that one in mind. I tried the bit of kit you thought might work TransAtlantic, holding it in the vice, but the plastic's flexible when held on just one side,

so I used the guide from it with the wood jig version Nev suggested, holding it tight in place with my thumb and the rest of my hand on the workpiece, and it really helped keep the drill going straight:

(I used 6mm dowel on this bit to try that out.) It's still not perfect but way better and will be easier once I've built the jig more solidly and figured a way to hold the work piece really steady.

Sawing the unsupported piece on the bandsaw's not easy - the blade wants to push it down, so again I need to figure a way of supporting it to counter this.
Cheers, C

 

[transatlantic]

What about hot gluing the drill guide?

 

[Chris152]

What about hot gluing the drill guide?

Found it quite difficult to align the tip of the drill bit where I needed the hole with the plastic guide in place - I couldn't see it so well. So I made another version of the jig using the metal guides hot glued to the jig:

It works really well, and it's easy to hold the piece tight against the jig and see exactly where the tip of the bit makes contact. I did another test piece this morning, and think it worked just about perfectly - though I don't think the slice was taken from the right place.

The only real problem I have now is that the teeth on the bandsaw want to tearout - I changed the blade to 6 tpi but still there. One day I'll get a table saw...
Really appreciate everyone's help.
C

 

[RogerP]

Ask Ian at Tuffsaws if he can recommend a bandsaw blade that will give the minimum, or even no, tearout.

 

[Chris152]

Thanks Roger - I've emailed him and see what he says. It's also the rake (I think that's the term) of the teeth that leave their mark, but that's less an issue as I can sand it away I think.
C

 

[J-G]

...It's also the rake (I think that's the term) of the teeth that leave their mark, but that's less an issue as I can sand it away I think.

I suspect that you mean the 'Kerf' which is the amount of 'set' there is to each saw-tooth - usually alternating left and right for adjacent teeth - which creates the clearance for the saw-blade body to avoid 'binding'.

Incidentally, I very seldom use anything coarser than a 14 tooth bandsaw - usually 24 or 32 - yes, it takes longer but the finish is vastly superior.

 

[Chris152]

Thanks J-G - I mean 'set', as you say - the little teeth marks protrude either side of the cut.

The suggestion - based on that the cut for each bowl ranges from 2 inches to the pointed edge (so cutting from 2" to nothing, gradually) - is either a 1/2" x 6/10 M42 blade, or a 1/2" SuperTuff Carbon in either 10tpi or 14tpi. I'm sure it'd be easier to advise if it were a consistent width of wood being cut.

I'm tempted to go for the 14 tpi, just because I figure there'll be less set - unless anyone can advise otherwise?

Thanks

C