bowl shape doodling software

Stumbled on this free software to create bowl and hollow form shapes and didn't know where to put a link but this is entertaining and useful. Software to design a bowl or hollow form then print and cut out to make a template. We may not want a template for more than rough forming but it gets you started. Fun to doodle with the software and every once in awhile I make something I want to save. I struggle a little with the bottom shape and working with this and the 3-D model in the side pane should help me. Documentation is slim but with a search in help I found that you double click a spot to add a new point to move around and just drag a point out of the work area to get rid of it. Easiest to make a smoothly flowing form using the fewest possible points to define it so after getting a shape you like getting unnecessary points out of the way may smooth the lines. I haven't found a way to do sharp corners, I think you have to just put several points very close together, not hard with the zoom, or maybe make a design in several sections on different drawings. Not super sophisticated for free but with instant three dimensional imaging in the side pane it seems pretty fancy to this old CAD operator from the age of dinosaurs!

Sorry if this is already posted, I didn't find it in a search.

Hu

http://www.billooms.com/bowlshape.html
 
Yeppers, Bill's little bowl program has been around for a while, but it's definitely a handy tool, especially for folks who are getting a feel for forms they like. :thumb: It's a handy way to illustrate the fact that sometimes a little tweak in the form can make a big difference in the final look.

You mentioned templates for roughing bowls...that's a sign of your metalworking experience showing through. ;) With metals, you have a predictable material throughout the blank. With wood, sometimes a fault or feature in the blank will dictate what can be done with it. I think most guys approach a bowl blank with a fairly open agenda. I know in my own case, I might have a slight idea of what I want to make, but no real concrete plans for the form. Then, as I strip away the waste wood and things unfold, I can get a better idea of what would look best with that particular piece of wood. And that may or may not be what I started out to make.

Still, experimenting with software like Bill's is good practice for fine-tuning forms. :thumb:
 
The template doesn't always take you very far, that's a fact! I seem to see curves a little differently on the lathe and on the shelf, the curve between the sidewall and bottom is usually steeper than anticipated for example. I'm kinda thinking making a template of my outside wall after it is shaped and reversing it to have an inside template might be of help to me too. It would show me how much different the two shapes are and give me a pretty good idea where I could whittle a little more off.

I started a piece yesterday, was pretty sure it wouldn't work when I started since I haven't seen anything quite like it. No surprise, it didn't work so now I have a tall hollow form started roughing. I'll eventually make something else out of it.

A bit of trivia, stone isn't too consistent either! Michelangelo's David was designed around a crack in the marble. Worked out pretty good for him. ;)

Hu
 
The template doesn't always take you very far, that's a fact! I seem to see curves a little differently on the lathe and on the shelf, the curve between the sidewall and bottom is usually steeper than anticipated for example. I'm kinda thinking making a template of my outside wall after it is shaped and reversing it to have an inside template might be of help to me too. It would show me how much different the two shapes are and give me a pretty good idea where I could whittle a little more off.

I started a piece yesterday, was pretty sure it wouldn't work when I started since I haven't seen anything quite like it. No surprise, it didn't work so now I have a tall hollow form started roughing. I'll eventually make something else out of it.

A bit of trivia, stone isn't too consistent either! Michelangelo's David was designed around a crack in the marble. Worked out pretty good for him. ;)

Hu

I usually get the outside where I want it (or more commonly where it ends up.. :rolleyes:) and then use a pair of calipers to keep the thickness ~mostly consistent (~mostly because I'm getting better, but well .. yeah there is often a fair bit of variation). The biggest problem I have is with the bottoms, so far I haven't made a funnel - I'm pretty sure that means I'm being overly conservative :D

Calipers like this is what I mostly use:
http://www.woodturnerscatalog.com/p/5/-/19/86/-/5113/Turners-Select-Inside-Outside-Caliper
Although these look interesting (heck they have a plethora of types here):
http://www.woodturnerscatalog.com/p/5/-/19/86/-/5105/Turners-Select-Double-Ended-Caliper
I haven't used them.. At this point consistent cutting is looking more important than consistent measuring so working on that :D

Looking at shapes and curves is pretty interesting though often something I didn't think would look good ends up actually being kinda cool - and vice versa so its been educational to me to try things and see what it ends up like in wood - although hitting a specific mark is often elusive.
 
I usually get the outside where I want it (or more commonly where it ends up.. :rolleyes:) and then use a pair of calipers to keep the thickness ~mostly consistent (~mostly because I'm getting better, but well .. yeah there is often a fair bit of variation). The biggest problem I have is with the bottoms, so far I haven't made a funnel - I'm pretty sure that means I'm being overly conservative :D

Calipers like this is what I mostly use:
http://www.woodturnerscatalog.com/p/5/-/19/86/-/5113/Turners-Select-Inside-Outside-Caliper
Although these look interesting (heck they have a plethora of types here):
http://www.woodturnerscatalog.com/p/5/-/19/86/-/5105/Turners-Select-Double-Ended-Caliper
I haven't used them.. At this point consistent cutting is looking more important than consistent measuring so working on that :D

Looking at shapes and curves is pretty interesting though often something I didn't think would look good ends up actually being kinda cool - and vice versa so its been educational to me to try things and see what it ends up like in wood - although hitting a specific mark is often elusive.

Ryan,

You just hit on one of my concerns. It isn't specific marks I am trying to hit as much as specific marks I am trying to miss, funnels and unplanned piercings! I have calipers, plenty of medium sized ones. I wish I could find them. I have one very small set I can find but since they don't reach as far as my fingers they haven't done me much good.

I'm kinda thinking that sans calipers I can cut a template to match the outside pretty closely, then use that template to mark and cut an inside template. Whack a half inch off the bottom and round the bottom corner pretty nicely and see how it works out. Push come to shove homebrew calipers might happen. I just remembered I have a few hundred feet of quarter or five-sixteenth hot roll round bar up the road. A wooden hinge and calipers can be had, shaped however I am in the mood. Might work, might not. The bar stock is where my bandsaw is and it seems like my bandsaw has been missing me, time to bring it up here on the farm when I get a chance.

Just had a late breaking thought. Had to chase it around with a butterfly net awhile but I finally caught it before it escaped forever. Have you tried a bright light? A light shines through some fairly thick wood and I would think would show thick and thin very good. Might have to play with that soon. Actually I think I have to go clean up my play area and mow the grass pretty soon, after that I can play with the lathe some more, maybe. Sure wish they would come out with a variety of grass with good fill that grew to two and a half inches tall and stopped there.

Hu
 
Boy howdy you're getting thinner than I am if a light shows through very well! Most bowls I manage to get down into the 1/4" to maybe 1/8" range; I think at the thinner end of that the light might work, although have never tried it in this context.

The reason I like calipers over inside templates is that the wood starts to get pretty flexy in the 38" - 1/4" or so (depending on the type, dyness, size, etc...) so I find it easier to do something about like the following (ain't saying this is the best way, just mostly works for me most of the time):
  1. Turn the outside to the shape it ends up at
  2. Rough the inside, leave the walls fairly thick (I hear words like "1/10 the diameter but I just eyeball it to "fairly thick")
  3. Start turning the inside to finish. I usually do about 1" or so at a time to "pretty close and then when I get a ways in (maybe 3" or there abouts) do another "finish pass" to clean it up a little which is the last cut before sanding. The finish passes are a good excuse to take a short break and resharpen the chisel as well :D

This way the wood is plenty sturdy where I'm actually cutting so it doesn't bounce around to much. The finish cut I take pretty fine so it doesn't cause a lot of flex. When I try to work the whole thing down at once I end up with more "decorative scalloping" than I'm happy with which I guess can look kinda cool, but not when its unintentional (weirdly I read about someone else having the issue and what to do to NOT have it and then started having more issues.. go figure).

An inside template would - I think require a more continuous reduction so you loose the "thick bottom" stability.

The biggest problem I have with calipers is right at the bottom you can't really measure that with them so its a little more guess and by golly (and yes I'm familiar with the T stick trick - but I tend to conservatively leave a bit more than needed on the inside so it has enough to survive when I return the outside of the bottom... and well yeah.. my head isn't there yet).
 
Like Ryan, I turn the inside of a bowl in stages, so a template would be of little use until i was pretty much done anyway.

I have some calipers, but very seldom use them. You might be surprised how accurate your fingers can be in feeling variations in thickness...even if the fingers are on separate hands (like when reaching inside a larger bowl). As far as knowing how much meat to leave in the bottom, that just comes with practice and experience. I usually just hold the gouge parallel to the lathe bed on the outside of the bowl, line up the tip of the gouge with the outside bottom of the bowl, then use my thumb to mark where the rim of the bowl is. Then, I put the tip of the gouge on the inside center of the bowl, close one eye and line myself up with the rim of the bowl, and see how far my thumb is from the rim. It's good for a ballpark guess, which is all I really need in most cases. We're not building pianos here. :D
 
I have some calipers, but very seldom use them. You might be surprised how accurate your fingers can be in feeling variations in thickness...even if the fingers are on separate hands (like when reaching inside a larger bowl).

Good point - fingers are also a LOT more sensitive to bumps as well, I can definitely find deviations better with them - I find the calipers mostly handy as a cheat to keep the general thickness more consistent otherwise with just fingers I've found its easy to "drift" in or out on the size a little bit - as you say I'm sure experience will improve that - for now - all the help I can get :D

It's good for a ballpark guess, which is all I really need in most cases. We're not building pianos here. :D

unless we are.... .... ... http://en.wikipedia.org/wiki/Thumb_piano <- on my list for a very long time, I'm starting to think a turned version might be pretty interesting... ;) :rofl:
 
the template is more of a failsafe when I think I am done.

I need to build a lathe stand instead of it sitting on the workbench it is on now. When I get down past finger deep into a bowl and even before I tend to get thicker and thicker sides as I go down. I do go down in steps when trying to go pretty deep. My bench ain't the stiffest and between that and the natural tendency of thin walls to move around and vibrate when I do succeed in getting the walls thin steps are the only way to go down.

I may be able to give something back here for a change. I have no difficulty finding the bowl or vessel bottom thickness. Two reference planes are all that are needed, actually lines on those planes but I think of the reference surfaces as planes. Hopefully the front of your headstock is flat but if not it is easy enough to use something square like a smallish carpenter's square or try square. Doesn't matter at all, all you need is a vertical reference line that you can return to over and over. That is your first reference plane. I use the front of the plastic dust cover on my headstock. I might be a sixteenth off measuring it in different places but a sixteenth isn't an issue for me, I leave the bottoms an eighth inch or more thicker than sidewalls anyway. A couple times I left the bottom several inches thicker which was a disappointment when I took the piece out the headstock.

Anyway, from this reference line measure to the front of your chuck jaws, faceplate, glue block, whatever is holding your work in progress. Happens to be four inches to the front of my jaws on my Talon, an easy number to remember and since it is fixed, after you measure once it never changes. Next place your long tool rest in front of whatever you are hollowing at a convenient distance eyeballing it perpendicular to the lathe ways. Working on a bowl yesterday I set my rest fourteen inches from my first reference plane. You could measure from each side back to a reference plane on your headstock or placing your right angle device on each side but I find eyeballing close enough for this purpose. The distance is whatever you want it to be so just pick one that makes the math easy. For example, had the front of my chuck jaws been 3.75" from my reference plane I might set my tool rest another ten inches in front of that for easy math at 13.75 from my reference plane. Lay your tape measure or whatever is handy with a scale on it across your tool rest and down to the bottom of the bowl. Now I have a single number to subtract from ten inches in my examples since the front of my jaws are the same location as the bottom of my bowl. Ten inches minus measurement equals bottom thickness.

It may sound involved but in practice it took less than a minute the first time I did it and once I had all of my reference numbers in place it might take ten seconds to check bowl or vessel depth. Since the front of the headstock or something else that never changes is one reference plane and the tool rest is the other, it matters not at all what the shape of your bowl or vessel is. Natural edges and warpage aren't involved in your measurements.

One of those times a picture is worth more than all the words so if anyone reading this doesn't follow I will try to do a quick and crude sketch and snap a picture, I don't have any drawing software I know how to use.

Hu
 
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