Shop built thickness sander

Storebought or Homemade: Tell Us!
MaineGeezer
Posts: 1711
Joined: Wed Aug 13, 2014 12:14 pm

Re: Shop built thickness sander

Post by MaineGeezer »

I've tried the hook-and-loop attachment idea. It has a cushioning effect which seems to be advantageous compared to having the sandpaper directly against the hard drum.

I'm not sure I would trust it to hold the sandpaper by itself -- maybe the hook material I bought to go on the drum isn't the right kind to mate with the layer on the back of the sandpaper -- but I had designed my sander to clamp the ends of the sandpaper with with wedges (see photo) that go down into tapered slots on the drum. Those, together with the hooik-and-loop, seem to work really welly. I haven't used the sander much yet with this setup, but the test pieces I tried did great.
You do not have the required permissions to view the files attached to this post.
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
Skarsaune
Posts: 239
Joined: Mon Dec 03, 2018 9:12 am

Re: Shop built thickness sander

Post by Skarsaune »

Here's the table adjustment:

The whole table is mounted on hinges on the back:
IMG_2384.JPG

Under the front there's a threaded rod with a handle attached, and a nut welded to a bracket:
IMG_2383.JPG
A quarter turn of the handle gives pretty close to .010" thickness change. Not by design, it just worked out that way.

As far as the hook & loop sandpaper - it's worked fine for me for every part on the current build. Back, sides, top, binding, bridge, braces, etc, etc.
If you think about it - try separating velcro by pulling on the ends. The force on the paper is tangential to the drum as it contacts the work.
You just have to make sure you don't hit the leading edge. I have a line on my table to remind me not to go there.
You do not have the required permissions to view the files attached to this post.
MaineGeezer
Posts: 1711
Joined: Wed Aug 13, 2014 12:14 pm

Re: Shop built thickness sander

Post by MaineGeezer »

That adjustment is a lot simpler than what I came up with!

I found that that with only one support point the table would twist, so I came up with a weird and wonderful chain drive connecting an adjustment screw on each side of the table so they operate together. If you can get good results with one adjustment screw, you're fortunate.
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
JLT
Posts: 296
Joined: Wed Nov 02, 2011 9:13 pm
Location: Sacramento, CA USA

Re: Shop built thickness sander

Post by JLT »

Thanks for the write-up! You've given me some ideas.

I'm still not convinced that you don't need some sort of feeder mechanism instead of hand-feeding it, but if it's worked for you, it would certainly simplify construction. I suppose that one could always add some sort of feeder later on.
MaineGeezer
Posts: 1711
Joined: Wed Aug 13, 2014 12:14 pm

Re: Shop built thickness sander

Post by MaineGeezer »

Hand feeding does indeed take some practice, and I still can't avoid a slight bit of waviness. It's generally within range of being sand-outable though. Some woods are easier than others to get flat, too. Generally, harder woods are not as sensitive to minor variations in the feed rate as softer woods.

I thought about a power feed, but it rapidly got more complicated than I wanted to deal with.
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
Morecowbell
Posts: 280
Joined: Thu Feb 21, 2019 10:51 am
Location: Fishers, IN

Re: Shop built thickness sander

Post by Morecowbell »

As I make slow progress on my first build, a thickness sander has gone from a curiosity to the next project!

The roller is really my big question - looking at the different approaches to DIY builds on the web there's the wood disc approach, the PVC pipe approach, and then you could just buy the Performax 18/36 roller for $179, which isn't cheap but might be worth it to get past that issue and be sure that you have a good roller. So was curious what those who have done it have learned and would consider or recommend?

Many thanks and stay safe!

Clay
"Facts seldom sway an opinion." - John Hall
"The difference between theory and practice is that in theory there is no difference." - Van de Snepscheut
MaineGeezer
Posts: 1711
Joined: Wed Aug 13, 2014 12:14 pm

Re: Shop built thickness sander

Post by MaineGeezer »

That's an interesting possibility. One thing it would get you, I assume, is a good way to attach the sandpaper to the roll and a source of sandpaper designed to fit it. While one can come up with one's own solution to those problems, it would be a plus not to have deal with them.
The only negative I can think of offhand is the greater cost vs. one constructed of wood, PVC, or whatever, but after adding up the cost of materials to make your own, the incremental cost may not be all that much, especially if you put any value at all on your time, and the end result is likely to be at least somewhat better.

If you're going to build an 18" sander, buying the roller for $179 seems like a pretty reasonable option to consider.

I made my roller out of a bar of 3" diameter Delrin, but it's only 9" long. Making one 18" long would have been more expensive and more difficult.

One question to ask is, do you want to build a sander for the experience of building a sander, or do you want to have a sander?
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
Morecowbell
Posts: 280
Joined: Thu Feb 21, 2019 10:51 am
Location: Fishers, IN

Re: Shop built thickness sander

Post by Morecowbell »

Great question. Earlier in the process I would have been more on the building it side, but as things progress I'm moving to the having it side. There's plenty to learn and build along the way without adding to the list! But as I'm working through some pretty ornery EIR grain on these backs I'm understanding why people use them.
"Facts seldom sway an opinion." - John Hall
"The difference between theory and practice is that in theory there is no difference." - Van de Snepscheut
MaineGeezer
Posts: 1711
Joined: Wed Aug 13, 2014 12:14 pm

Re: Shop built thickness sander

Post by MaineGeezer »

One thing: I don't think I would try to build a cantilevered version, with the drum supported on only one end. I think it would be difficult to make the support rigid enough to keep it from flexing under load and creating a sideways taper. on what you were sanding.
If the drum you are contemplating buying comes from that type of sander, be sure you can piut a bearing support on both ends when you incorporate it into your design.
Don't believe everything you know.
Anything is possible if you don't know what you are talking about.
When things are bad, try not to make them any worse, because it is quite likely they are bad enough already. - French Foreign Legion
Skarsaune
Posts: 239
Joined: Mon Dec 03, 2018 9:12 am

Re: Shop built thickness sander

Post by Skarsaune »

Morecowbell wrote:As I make slow progress on my first build, a thickness sander has gone from a curiosity to the next project!

The roller is really my big question - looking at the different approaches to DIY builds on the web there's the wood disc approach, the PVC pipe approach, and then you could just buy the Performax 18/36 roller for $179, which isn't cheap but might be worth it to get past that issue and be sure that you have a good roller. So was curious what those who have done it have learned and would consider or recommend?

Many thanks and stay safe!

Clay
There's also the surplus conveyor roller route, like I did. $10 at the industrial scrap yard, and an hour in the machine shop truing it up.

A lot depends on your scrounging and fabricating skills and resources. Many ways to skin a cat.

I'm usually one who just wants to use the darn tool, not spend forever building it - but I'm really glad I built this one. I use it a lot and don't have much in it.
Post Reply