Progress is happening on this project but it is slow.
I made some wheels for the bandsaw out of MDF but ended up scrapping them because I saw no feasible way to solve two problems:
1: Alignment of the shaft to eliminate lateral wobble. The wheel was a sandwich of two pieces of 3/4” MDF with a hole in the middle and the shaft rammed into it.
2: affixing the shaft to the wheel in a removable fashion. I would have had to resort to epoxy or something to secure the shaft.
I also have doubts about the durability of MDF considering how much tension I plan on applying with this machine.
I decided to make new wheels using a number of segmented parts laminated together (similar concept to how the frame was constructed). These new wheels will be a ‘split’ design and will actually be made in two halves and bolted together onto the shaft. A design element I’m tinkering with is actually drilling a hole perpendicularly through the shaft and using a bolt to mechanically secure the shaft onto the wheel. I don’t have any metalworking equipment except my drill press, and so machining a keyway or similar would be difficult. Since I am concerned about creating a weak point by removing too much shaft material with a through-bolt, my other thought was to drill a short ways in and use a tap to cut a few threads, just enough for a bolt or screw to engage and snug up against and this would act like a key and prevent the wheel from free spinning on the shaft when under load.
This is what my design is inspired by.
Here’s the Solidworks design I came up with:
EDIT:
The wheels are made from hickory and maple. I don’t know the exact subspecies of each but neither were very expensive. The hickory was a 4/4×7” and was a lot more warped than it seemed when I bought it at the dealer. The maple started out as 6/4 and I was able to resaw it on my tablesaw and end up with a piece that came out at 3/4” and one at about 5/16” after planing. Fortunately the maple was quite flat and was sold as hit & miss but was a lot closer to S2S.
I’ll be using Urea Formaldehyde powdered plastic resin glue for this, the same as on the frame.
And here is what I have done at the time of this post:
Parts
Constructed a jig for making precise 30-degree and 15-degree cuts on the tablesaw. It required a fair amount of tuning before I got accurate results.
Milling out stock. You can see the CAD plans as well.
Sorry about the wierd banding issues in the images, I think the fluorescent light above is causing that.
Thanks for reading. Stay tuned for the next post where hopefully I have completed wheels to show.
-- Woodworking from an engineer's perspective
2 comments so far
BTimmons
home | projects | blog
2303 posts in 3492 days
#1 posted 06-23-2014 03:44 PM
That’s an amazing amount of work. I’m in awe of anyone who undertakes building their own power tools on that kind of scale.
-- Brian Timmons - http://www.BigTWoodworks.com
William Shelley
home | projects | blog
609 posts in 2477 days
#2 posted 06-23-2014 03:51 PM
Thanks. I’m a firm believer in the phrase, “If it’s worth doing, it’s worth overdoing.”
-- Woodworking from an engineer's perspective
Have your say...