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| bobbollin |
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  Registered Member #91 Joined: Sat Aug 30 2008, 08:26AMPosts: 48 | I started a separate thread because it looks like we're hijacking Charles' thread about the Byrnes saw. Perhaps one of the moderators could move the rest of the thickness sander discussions here?? I agree with Bob H. about the sources. I got my basic idea on the sander from the link I gave in the post above where Mr. Herrick has his description. I also got a lot of assistance from a fellow club member, Gary Ison, who had already built a sander and inspired me to take on the task. The actual execution is dependent on many variables, such as the available space in your shop, the physical size of your motor, the width of sanding roller that you want, the clearance you desire to have between the sanding roller and the table, the length of table you desire, etc., etc. I probably spent at least as much time thinking, drawing, planning and revising as I did actually cutting and assembling wood. I used Baltic birch plywood in building mine. Baltic birch is expensive but is well worth it in my opinion. It is easily worked, takes finish well, has no voids, is attractive and is very sturdy. In my case it also cost $75 for a 5' X 5' sheet, which is more than enough for just the sander project. I made the base out of less expensive materials since I planned on painting it from the get-go. I can write descriptions of what I did in building mine as well as provide photos if anyone thinks it would be of value. But do take note that, as I said above, you should have, or have access to a number of large woodworking tools and have the skills to use them in order to complete this sander. I can add a few mods that I made to Mr. Herrick's fine notes on building the machine and some ideas that I picked up from Gary that I thought were quite clever and useful. It's a fun project and a tool well worth having. It is certainly not beyond the scope of the home woodworker with average skills. It presents a few challenges, yes, but I learned a few things and had a good time and got a lot of satisfaction from the job. Best Wishes Bob B. Nautical Society of Oregon Model Shipwrights | ||
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| robp |
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| Registered Member #125 Joined: Sat Aug 30 2008, 04:09PMPosts: 16 | Bob, R.J. Potter | ||
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| bobbollin |
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| Registered Member #91 Joined: Sat Aug 30 2008, 08:26AMPosts: 48 | OK Rob, I'll see what I can come up with. The first thing I would recommend, however, is to go to Mr. Herrick's write-up on the subject and print it out for future reference and read through it as well as the link that is there to Mr. Larson's article. You'll find it helpful. http://home.att.net/~ShipModelFAQ/ShopNotes/smf-SN-ThicknessSander.html Best Wishes Bob B. Nautical Society of Oregon Model Shipwrights | ||
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| robp |
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| Registered Member #125 Joined: Sat Aug 30 2008, 04:09PMPosts: 16 | Bob, Thanks for the link. Will do. Rob R.J. Potter | ||
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| bobbollin |
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| Registered Member #91 Joined: Sat Aug 30 2008, 08:26AMPosts: 48 | Before I begin, I need to give credit where it is due. Most of the ideas I used for making this sander were either a result of Mr. Herrick's notes or from ideas that were helpfully passed along by Mr. Gary Ison of the Nautical Society of Oregon Model Shipwrights. It would be very difficult to assign credit for each phase or item in my description. Assume that all credit belongs to these two gentlemen unless I specify otherwise. Any and all measurements are solely mine. I am sure that any sander made from this description will be unique. First considerations. 1) A motor: I was lucky in that I already had a 1/2 h.p. motor on hand that I pulled from an old table saw that I had replaced back in March. 1/2 h.p. is probably as big as you'd need to go on this tool. Gary's sander is 1/4 h.p. and it seems to be very adequately powered. Remember that you are only taking off about 1/16" maximum on a pass with this sander. If you make it labor too much you'll burn the wood. There are numerous sources for motors on the Internet. I am sure that, as Mr. Herrick suggests, there are also sources for used motors, such as old furnace motors and the like. A little ingenuity and searching here would probably help. You'll need to know the physical size of the motor in order to plan the size of the "box" on your sander. This is probably not a major issue, but it could be and it helps to have the major components on hand, if for no other reason than self-assurance that you are proceeding in the right direction. I would recommend that you obtain a motor with a flat (otherwise known as a "cradle") base mount for ease of assembly. The speed of the motor will probably be somewhere in the area of 1800 or 3600 rpm and the direction of rotation will be CCW or CW. None of these are important considerations since they can all be dealt with later. Drill Rod shaft and bearings: There are numerous sources for drill rod and bearings. One place to find both drill rod and the steel dowel pins that Herrick recommends and that I used in mine is www.fastenal.com . If you are lucky they will have a retail store fairly close to you. On the Internet they only want to sell dowel pins by the box of 100. You only need 2. If you deal with the store they will sell you 2. I used 1/2" rod for the shaft. This is all you need and matches standard available pulleys and bearings. I got my pillow block bearings from www.smallparts.com . Get the type with grease fittings.  Drill rod and the bearings come in tolerances of +/- .001" or so. In my case the rod was a bit oversize. I had to reduce the diameter. This took a bit of creativity. I was able to come up with a Rube Goldberg arrangement on my wood lathe so that I could use a file to reduce the diameter of the rod on the ends.  I clamped the rod in a collet at the headstock (a drill chuck in the headstock would work just as well) and then clamped a wood block to the tool rest which I positioned perpendicular to the rod. A V-notch cut in the top of the wood block supported the rod and kept it from wandering and the height was easily adjusted with the tool rest. In this way I was able to use a mill smooth file and reduce the diameter of the rod so that it was a snug fit in the bearing. At this time you also must determine how wide you want your drum to be. I decided on 12" for mine since I would be using it for other purposes like toy-making for the grandchild as well as modeling. What width you want is strictly up to you. You must cut your rod to length (a hacksaw will work), allowing for the width of the drum plus about 1/2" for the dust hood attachments, plus about 1/2" of "slop" all around, plus the amount that will go through the bearings, plus enough to hang out one end and accept a pulley. In my own case, with a 12" wide drum, I used up an entire 18" length of rod.     Best Wishes Bob B. Nautical Society of Oregon Model Shipwrights | ||
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| bobbollin |
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| Registered Member #91 Joined: Sat Aug 30 2008, 08:26AMPosts: 48 | Making the roller. Mr. Herrick advises using maple for the roller. I used oak because maple is difficult to get out here and rather expensive. Oak is available at the local Home Depot and works just fine. I used two pieces of ¾” and one piece of ½” to laminate each half of the roller block. I wanted to end up with a 3” diameter roller, so using these thicknesses gave me a 4” square block which allows for trimming waste and turning waste as well. I used polyurethane glue to laminate the halves. It's messy stuff as it expands a bit when it sets, but it's strong and I would be trimming off all the squeeze-out anyhow. I clamped it a well and left it overnight.  After the halves were set up, I routed a ½” wide groove, ¼” deep down the centerline of each block to allow for inserting the drill rod shaft. I used a ½” cove bit and a router table to do this and it worked very well. The drill rod needs to have 2 holes drilled through it for the steel dowel pins. I simply used one of the block halves as a support for the rod and drilled through it on my drill press. After that was done, I also had to drill holes in the wood block halves for the dowel pins to rest in during assembly.  I did not feel it was necessary to use screws in the block. I roughed up the surface of the drill rod with 60 grit sandpaper and used epoxy to join the halves together with the drill rod shaft sandwiched between them. Don’t forget the dowel pins!! I know that the manufacturers say that polyurethane glue will bond well to metal, but I have always used epoxy for this type of application and have had good success with it, so I trust it and used thirty minute epoxy. I made sure that every square millimeter of the wood surfaces was covered with glue, including the holes for the dowels. Thirty minute epoxy really takes a bit longer (like hours!) to set up, so I left this clamped overnight before attempting machining.  When the block/shaft assembly was complete, I had to trim it to close to size. I chose to make the block 3 ½” square before turning, which meant trimming ¼” off of each side.  After that was done. I had to trim off the corners to make my square block into an octagon. To accomplish this I simply made a sled from a piece of scrap 2 X 4 with a 90 degree V-notch in it and trimmed it to the appropriate width on my table saw.  Then it was simply a matter of putting the block in the sled and guiding the sled along the fence to trim off each corner.  More on turning the roller later… Best Wishes Bob B. Nautical Society of Oregon Model Shipwrights | ||
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| bobbollin |
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| Registered Member #91 Joined: Sat Aug 30 2008, 08:26AMPosts: 48 | Turning the roller was not difficult once I figured out how to mount the thing in the lathe. It required a bit of a Rube Goldberg arrangement. I have a collet-type chuck that I used in the headstock. A simple 1/2" key chuck similar to what is on a drill press would work as well if you have one...anything that will clamp down on the 1/2" rod in the roller.  At the tailstock I mounted one of the bearings that was to be incorporated into the final sander assembly onto an appropriately-sized set of blocks made from scrap 2 X 4 and smaller pieces of wood. I added shims until the central rod in the roller was level with the headstock and clamped the assembly to the lathe bed. Although it is not shown in the photo above, I eventually placed a small block of wood between the lathe tailstock and the end of the rod so that I had something to tighten the tailstock against. It all looks a bit crude but it was quite effective. From there is was simply a matter of establishing a 3 1/8" diameter at a number of points along the length of the roller drum using a parting tool and a pair of calipers. Then I turned down the sections between these notches so that I wound up with a cylinder that was roughly 3 1/8" in diameter. Precision isn't essential here as you do the final sanding for flatness and diameter on the thickness sander itself, using fairly coarse-grit paper (I used 80 grit). Best Wishes Bob B. Nautical Society of Oregon Model Shipwrights | ||
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