A Wobble Bowl

[PeteG]

I thought this was going to be a fairly easy project I could make in a two or three hours, a 7" Wobble Bowl. The wood is a little thicker than the plans suggested so it stands a bit taller.
I started cutting the base with a Hobbies No5, the cuts were nice and clean and accurate but the blade soon lost it's egde. After finishing the base I swopped blades for an Olson PGT No5.
I've been having problems with tension on the PGT's, when I thought I had the tension right the blade would come out of the top or bottom holder soon after turning the saw on. I kept
playing with the tension until I could keep the blade in the holders, but the downside is, the sections would only remove from above, so the sides were angled. I also ended up with quite
a few burn marks. Each blade would cut just over one section before I had to replace it, but on the last piece I switched to a No7 for cutting the outer circle.
I spent a few hours on the bobbin sander removing the burn marks and trying to straighten the sides the best I could, so each piece is a bit thinner than it should be which didn't
leave a lot of room for glueing. Now it's it had a coat of Wood Silk I'm quite pleased, and hopefully the next one will be easier .

 

[bodge]

I "might" have the patience to cut that on the scrollsaw, but I certainly wouldn't have the patience to sand it all! Well done Pete, it looks really nice. 8)

 

[Chippygeoff]

Very nice piece of work there Pete. It looks perfect to me. I can't see a fault anywhere. Are you covering the wood with clear packaging tape to help prevent burning. I think I would have gone for a number 7 blade to cut all of the pieces, which I feel would have prevented some of the burning but it depends on how big the bowl is and how thick the wood is.

 

[monkeybiter]

That looks great, nice wood and nice work.

 

[PeteG]

I "might" have the patience to cut that on the scrollsaw, but I certainly wouldn't have the patience to sand it all! Well done Pete, it looks really nice. 8)

I'll do my best to make sure there's less sanding next time Bodge, but once I'd started, there was no going back

Very nice piece of work there Pete. It looks perfect to me. I can't see a fault anywhere. Are you covering the wood with clear packaging tape to help prevent burning. I think I would have gone for a number 7 blade to cut all of the pieces, which I feel would have prevented some of the burning but it depends on how big the bowl is and how thick the wood is.

Hello Geoff Yes, I've been using masking tape to cover the wood and then sellotape to hold the pattern down. I struggled a bit trying to get the No5 blade through the holes, I only have 50mm cutting depth on my Sealey and I think I was at the limit with this for internal cuts. I used a 1.5mm drill bit which I think was a little small for the No7, and the next one up is a 3mm bit.
I've checked the pattern again and I'm pretty much right with the timber thicknesser, it says 5/8" and used 14mm. I know I tried a few different speeds to find a balance between cutting and accuracy, but them
I'm still learning

That looks great, nice wood and nice work.

Appreciated Monkeybiter, I should have mentioned the wood, I think it's Oak, but after one of my previous posts, I wouldn't bet on it!

 

[Claymore]

looks lovely Pete, if you are getting an angle and burning on your wood it could be your putting too much pressure/speed while cutting? my first Intarsias used to do the same and these guys recommended i check the blade tension and also take my time and just put enough forward pressure on the blade so it cuts....... after a while i got to the stage where i used a nice steady pressure and my cuts improved and no burning. Worth trying.
Cheers
Brian

 

[gilljc]

Nice cutting and really good sanding =D>
Shame about not being able to get enough tension on the blades to make it easier for you, sounds like your clamps are maybe not as grippy as they could be, and lack of enough tension will cause blade irregularity and cause them not to cut well and wear quicker
I have made two or three of these bowls, and have used wood as thin as 9mm, which give a nice shallow bowl, one I made a piece of wood out of 3 different colours, and when I glued it up a little twist at each layer gave a nice swirling effect, though I am sure you know all this.
I have a nice pattern I found on youtube for a bowl with some variety in the 'wobbles', if you were interested you could pm me your email and I will forward it to you, or anyone else who is interested

 

[nadnerb]

Nice work Pete, I just wrote in another thread that if you use a industrial packing tape instead of sellotape it works better and should stop the burning
Regards
Brendan

 

[martinka]

Very nice, Pete, much better than my attempt at one of those bowls.

Both #5 and #7 PGT blades should fit through a 1.5mm hole, and in fact they should go through a 1.2mm hole. Make sure you sand the bottom of the drilled hole and also use an awl, or something similarly pointed, in the hole to give it a slight starting taper; it makes it much easier to get the blade in. The #7 blade is near enough 1.2mm but if you take the sharp corners off the top of the blade, it should go through easy enough. I sometimes touch the end of the blades on the 1" belt sander to take the corners off.

 

[PeteG]

if you are getting an angle and burning on your wood it could be your putting too much pressure/speed while cutting?
Cheers Brian

Hello Brian It's possible I might have been doing something along those lines

Nice cutting and really good sanding =D>
Shame about not being able to get enough tension on the blades to make it easier for you, sounds like your clamps are maybe not as grippy as they could be, and lack of enough tension will cause blade irregularity and cause them not to cut well and wear quicker
I have made two or three of these bowls, and have used wood as thin as 9mm, which give a nice shallow bowl, one I made a piece of wood out of 3 different colours, and when I glued it up a little twist at each layer gave a nice swirling effect, though I am sure you know all this.
I have a nice pattern I found on youtube for a bowl with some variety in the 'wobbles', if you were interested you could pm me your email and I will forward it to you, or anyone else who is interested

Hello Gill The PGT's are very wide top and bottom compared to the same size Hobbies, and I've never had a problem with those popping out. I think I was at the limit of tightening the clamps yesterday without causing any damage, still, I'll not blame my little Sealey
Do you have any images of the bowl Gill? Not sure I understand the "Little Twist"! The pattern would be much appreciated, PM on it's way

Nice work Pete, I just wrote in another thread that if you use a industrial packing tape instead of sellotape it works better and should stop the burning
Regards
Brendan

Hello Brendan and I appreciate the tip, thank you. And it's only a week ago since I bought loads of sellotape from Lidl whilst it was in stock! But I do have a couple of rolls of the brown packing tape
so I'll give it a try

Very nice, Pete, much better than my attempt at one of those bowls.

Both #5 and #7 PGT blades should fit through a 1.5mm hole, and in fact they should go through a 1.2mm hole. Make sure you sand the bottom of the drilled hole and also use an awl, or something similarly pointed, in the hole to give it a slight starting taper; it makes it much easier to get the blade in. The #7 blade is near enough 1.2mm but if you take the sharp corners off the top of the blade, it should go through easy enough. I sometimes touch the end of the blades on the 1" belt sander to take the corners off.

Hello Martin and that makes a lot of sense. I could have done with something smaller than a 1.5mm bit, I thought it was quite small but after the time spent sanding, it's leaves quite big marks. I've read that some folk take the back edge off a bandsaw blade, have you tried it on a SS blade, or is the blade too small for there to be any benefit?

 

[jonluv]

Hi Pete .
Looks good

The Hobbies no 5 blades do tend to go blunt and a lot of friction is created--- one way I reduce this is to keep a stick of Beeswax next to the saw and occasionally run the blade through it
I find the problem with this type of bowl is the gluing part--- old eyes!!

Keep up the good work

John

 

[PeteG]

Hello Jon

The glueing up was a little tricky as there was less surface area after all the sanding, but I'll know next time. Great tip regarding the Beeswax Jon, much appreciated
There's a small heart shaped bowl I want to try but the sides have to be cut at an angle by titling the the table something I haven't tried yet, should be an experience!

 

[martinka]

I've read that some folk take the back edge off a bandsaw blade, have you tried it on a SS blade, or is the blade too small for there to be any benefit?

Pete, taking the corners off the back of the blade with a stone is supposed to make is easier to turn the blade in tight corners. I've tried it, but if I noticed any difference, it was probably wishful thinking. Having said that, it might make a difference with harder wood, which I haven't cut much of. Stoning off the burr on some blades does make a difference to the angle the blade cuts at.

 

[PeteG]

Stoning off the burr on some blades does make a difference to the angle the blade cuts at.

Thanks Martin. Sounds like it may be OK for cutting tight curves but not for following straight lines!

 

[Helvetica]

That would make a beautiful light pendant!

 

[ChrisR]

Pete.

Looks good.

I make these bowls and give to my Sister, to sell in the Cats Protection Shop, for their funds.
They sell well, as potpourri bowls/containers.

Take care.

Chris R.

 

[PeteG]

Hello Chris What kind of money do these sell for in a charity shop? I can see they would make nice potpourri bowls, I think mine my well end up as one! Gill has sent me a very nice pattern, hopefully I'll be making a start on t hat on the coming weeks

 

[ChrisR]

Pete.

Sorry, I don’t know how much they sell for in the Cats Protection shop, I just pass them to my sister, who takes them to the shop.

Take care.

Chris R.

 

[PeteG]

No problem Chris, I just wondered how much these would have sold for. If I'd have charged £8.00 per hour mine would have been quite expensive