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Art & Inspiration Creative dash knobs

Discussion in 'The Hokey Ass Message Board' started by Barn Hunter, Dec 11, 2016.

  1. falcongeorge
    Joined: Aug 26, 2010
    Posts: 18,341

    falcongeorge
    Member
    from BC

    The style of striped acrylic knobs we see here were in a how-to in Rod & Custom in the early fifties, they were more common in customs than rods, but if you are more concerned with "period correct" than "HAMB correct" that line becomes much more blurred. They were also in the Hirohita merc.
     
  2. falcongeorge
    Joined: Aug 26, 2010
    Posts: 18,341

    falcongeorge
    Member
    from BC

    I looked it up, it was R&C Nov. '53
     
  3. Moriarity
    Joined: Apr 11, 2001
    Posts: 30,778

    Moriarity
    SUPER MODERATOR
    Staff Member

  4. CowboyTed
    Joined: Apr 27, 2015
    Posts: 343

    CowboyTed
    Member

    Raiman, instead of threading the bakelite, you can find a female thread that fits your threads, and then simply glue the threaded female insert into your bakelite. That way you don't need to worry about cracking the brittle bakelite. You can see that I used a threaded brass insert in this shift knob, to avoid cutting threads into the plastic:

    [​IMG]

    In my case, I bought a three dollar knob at the hardware store, and then smashed it to get the threaded insert out, and use it inside my shift knob. For smaller threads, you can simply use a Chicago screw with the correct thread size, and cut the head off the female side then use it as your insert, or try to find a source for "rivet nut" or "blind nut inserts." That's a lot less likely to break your bakelite knob, since you only need to drill a hole into it the correct size to accept your insert and a bit of epoxy.
     
  5. falcongeorge
    Joined: Aug 26, 2010
    Posts: 18,341

    falcongeorge
    Member
    from BC

    You could probably use a riv-nut and GEEEENTLY pull the rig-nut tool JUUUST enough to fix it in place.
     
    brad2v likes this.
  6. Inked Monkey
    Joined: Apr 19, 2011
    Posts: 1,834

    Inked Monkey
    Member

    Sweet deal, @CowboyTed What are you using to shape the knobs?
     
  7. Raiman1959
    Joined: May 2, 2014
    Posts: 1,427

    Raiman1959

    That's a good idea!....instead of 'working' the original thread, I can drill a slightly bigger hole, and insert the proper dimension....thanks!....I got so I hated touching anything bakelite simply because they were always cracking no matter what I did...I appreciate the idea.!
     
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  8. Raiman1959
    Joined: May 2, 2014
    Posts: 1,427

    Raiman1959

    ....the riv-nut idea is a good idea....actually not thought of that option! Seems like when I'm fidgeting with anything bakelite and try to be extra careful, it just makes a bigger impression of what the split looks like in the knob! I'll try your idea and Cowboy Ted's idea....I'll proceed just a little bit more ''gentle'' and hold my breath!...maybe I can actually get the knobs to do what I want for change!....thanks man!;)
     
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  9. falcongeorge
    Joined: Aug 26, 2010
    Posts: 18,341

    falcongeorge
    Member
    from BC

    Just don't squeeze the handle of the riv-nut tool too hard, if you expand the riv-nut too much, the expansion will crack the Bakelite for sure. It will take some feel.

    I have been hunting online trying to find a nice translucent pink plastic without much luck. I was actually hoping to find two shades pretty close together and some white, so I could make the knobs tricoloured.
     
    Raiman1959 likes this.
  10. CowboyTed
    Joined: Apr 27, 2015
    Posts: 343

    CowboyTed
    Member

    OK, Inkedmonkey, here's a whole tech week post, just for you. It seems appropriate in the context of this thread, since I'm sure a lot of others would like to know how to use a drill press to turn small parts without a lathe.

    I'll start from the beginning of my process, recognizing that people may start with laminated materials and have a few more steps at the beginning. I start with a chunk of acrylic "pen blank" material, which is just the right size to make several knobs from a stick that costs only a few dollars. I cut them in half first, since my drill press has limited room, and cannot fit a whole 5.25 inch long pen blank.

    [​IMG]

    Now I want to start making it round before I start turning it, to speed the process. I use a drum sander with a coarse belt. Numerous other grinding and cutting tools would work too. This drum sander is quick.

    [​IMG]


    I sand off the corners to make an octagon first.

    [​IMG]

    Then I grind off each corner again and the thing starts to look roundish:

    [​IMG]

    Now we need to mount a shaft at one end to clamp into the drill chuck. Any of these bolts or rivets will work OK. They need to be flat, and we'll use a drop of super glue to glue them on one end of the shaft. Obviously they need to be centered. A bit less obvious is that the end of the shaft must be nearly perfectly square to the sides, or the thing will spin wonky and waste material.

    [​IMG]

    [​IMG]

    After the glue sets, chuck it into your drill press.

    With the table rotated out of your way, spin the workpiece. This is when you find out whether the end was square. If not, it will be obviously out of balance as it spins. Assuming it spins well, mark the bottom end with a sharpie as it is spinning.

    [​IMG]

    This is what you will see afterward. The point of this exercise is to find the true center of the spinning shaft, which is always slightly off center. The "live center" we are about to build needs to sit in a hole drilled in the true center. Now drill yourself a small hole in the true center as indicated by the black circle created by the sharpie. I use a small drill, about 1/8 inch diameter, and about an eighth deep.

    [​IMG]

    You'll notice that the sharpie mark and the hole in its center don't look like where you would mark the center of this tube using your eye. That hole IS in the true center as it spins in the drill, and that's what counts. The difference is created by the fact that the end where the bolt or rivet is glued on is almost never perfectly square with the sides.
    [​IMG]

    Now, let's build a makeshift "live center." This is the only equipment you'll need to convert any drill press into a small, light-duty lathe. It starts with nothing more than a bolt, a sealed bearing, a few washers and a nut. In my case, I needed the extra washers because the bolt fit snugly inside the bearing on the un-threaded part of the shaft. It was a bit loose on a bolt the same size with threads running all the way to the head. The washers fill in the un-threaded space on the shaft, so it fits tight to the inner bearing race when the nut is tightened down. Bolt it all together and then take the whole piece to a grinder, and let the tip of the bolt spin against the grinder until you've created a uniform taper on the tip. The exact size of the bolt and the bearing makes little difference. What counts is that the bolt fits snug inside the bearing. Use a sealed bearing, because this thing will be covered in dust all the time. An open bearing will quickly turn to crap in that atmosphere.

    [​IMG]

    [​IMG]

    Now, find a bit of hardwood and drill a hole the same diameter as the outer edge of the bearing. This board will sit on top of the drill press table and hold the live center in place. Don't drill your hole all the way through. Just drill it as deep as the bearing race is thick. The drill a second, smaller hole under it, so the head of the bolt has room to spin inside the second hole.

    [​IMG]

    Now set your live center in to the hole. It won't be bolted down, or attached in any way except by a snug fit. It will not go anywhere unless you use way too much force during turning.

    [​IMG]

    Now, go to the drill press and set the live center in place. Have a couple clamps ready to clamp the board to the table, but don't attach it yet.

    [​IMG]

    Chuck your workpiece into the drill and then rotate the table under it. Now ease the live center point up into the hole in the bottom of the workpiece. Lift the table so that the tip of the live center is snug inside the hole. Don't attach your clamp yet.

    [​IMG]

    Turn on your drill dress and let it spin at its slowest speed. The spinning workpiece will assure that the live center is centered. Now that it is centered, tighten your clamps to hold the board in place.

    [​IMG]

    You're now ready to start shaping the knobs. Speed up the drill to 1750-3500 RPMs. The faster it goes, the harder it will fling that chunk of plastic through your guts if you didn't tighten it down enough. You don't want that to happen. It hurts. Wear a leather apron, and have the ambulance on speed dial. ;) Double check that the work is spinning nearly true and that the live center is securely in the hole. Use very light pressure so you don't push the plastic right off the live center. Plastic is brittle, so a light touch is best to keep it from breaking. You can't lathe plastic with the kind of sharp tools and high pressure that you would use for steel. I use a rasp and a coarse file to form the basic shape, and then sandpaper to finish it up and remove the file marks.

    [​IMG]

    That tool on top looks like a file, but it holds strips of sandpaper and allows you to change them out to finer grits quickly.

    [​IMG]

    Once you have the basic shape, you use finer grits of sandpaper to smooth out the surface. I usually use the files, then 220 grit paper, then 500 grit, then 800 or 1000 grit. At that point, I'm ready to cut the two knobs apart. I'll remove the live center from below, but leave the piece chucked into the drill press, and use a light tap from a plastic mallet to knock the super glue joint loose at the top. Then I cut the two knobs apart and finish shaping and sanding the domes on the tops of the knobs by hand. Then it's off to the polishing buff to make 'em shine!

    [​IMG]


    [​IMG]

    I used the same process to shape the larger knob, except in that case I first drilled the plastic chunk, inserted a threaded brass insert in to the hole, and installed a short threaded rod into the insert. I then chucked the threaded rod into the drill so I didn't have to glue a shaft onto the top. Here you can see the brass insert in the bottom of the knob.

    [​IMG]
     
    Last edited: Dec 17, 2016
  11. brad2v
    Joined: Jun 29, 2009
    Posts: 1,652

    brad2v
    Member

    That is gold Cowboy Ted. Thanks.
     
  12. Inked Monkey
    Joined: Apr 19, 2011
    Posts: 1,834

    Inked Monkey
    Member

    Love it cowboy ted!
     
  13. Barn Hunter
    Joined: Feb 15, 2012
    Posts: 1,514

    Barn Hunter
    Member

    Lots of cool work and information sharing. Does anyone use a guide or template to make the knobs a consistent size?
     
  14. 31Apickup
    Joined: Nov 8, 2005
    Posts: 3,367

    31Apickup
    Member

    Cowboy Ted, nicely done!
     
  15. 5window
    Joined: Jan 29, 2005
    Posts: 9,516

    5window
    Member

    Not really knobs, but I had these dash plates made at a local advertising shop to my " designs". They cost about $10 each. One sits recessed into the wood dash, the other sits in a drop down panel made from a fuel filler door. The shifter has an insert of Fordite, but I don't have a photo. Fordite is cool stuff but I couldn't fine a big enough piece to use for knobs. Not as creative as Ted's but it fits my dash style.
     

    Attached Files:

    Last edited: Dec 19, 2016
    Barn Hunter likes this.
  16. Kustomkid
    Joined: Nov 21, 2010
    Posts: 531

    Kustomkid
    Member
    from Montana

    Yeah, a template is the way to go. I made a template for the dash knobs and the spotlight and shift handles. [​IMG]
    [​IMG]


    To chop, or not to chop. That is the question.
     
    Last edited: Dec 19, 2016
  17. Aussiepete.
    Joined: Oct 30, 2012
    Posts: 168

    Aussiepete.
    Member
    from Australia

    Thats awesome

    Sent from my SM-G925I using The H.A.M.B. mobile app
     
    OG lil E likes this.
  18. Hey CowboyTed, can you post the link to that funky blank material? I could only find various types of timber when I went looking for "pen blanks".
    I have found a couple of sources for threaded inserts- masonary anchors have a loose 1/4"-3/4"
    threaded insert which can be prised out, or "T" nuts- they have 4 points which can be ground off, and you are left with a threaded insert. Epoxy them in (12 hour stuff), and away you go.
     
  19. CowboyTed
    Joined: Apr 27, 2015
    Posts: 343

    CowboyTed
    Member

    Here's the place I ordered pen blanks from. https://www.woodturnerscatalog.com/t/6/Acrylics?b=88

    This is the "project blank" I used for the shift knob. At 1.5 x 1.5 x 6 inches it's much larger material than the standard skinny pen blanks, and useful for larger knobs like shifters or spotlights: https://www.woodturnerscatalog.com/p/66/6143/Turners-Choice-Acrylic-Project-Blank

    And here's another supplier, where OG lil E buys his plastic sheet scraps for laminating knobs. Look on the left column and scroll down to find solid color and translucent plastic sheet and plastic rods that might be useful for dash knobs.

    https://www.plasticareinc.com/

    I also thought about using T-nuts as inserts, and I probably will wind up using them for at least one of the knobs on my dash, which already has a threaded shaft.
     
    Last edited: Dec 20, 2016
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  20. jcmarz
    Joined: Jan 10, 2010
    Posts: 4,631

    jcmarz
    Member
    from Chino, Ca

  21. David Gersic
    Joined: Feb 15, 2015
    Posts: 2,730

    David Gersic
    Member
    from DeKalb, IL

    Google for "brass threaded wood inserts" for some possibilities.


    Sent from my iPad using The H.A.M.B. mobile app
     
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  22. Hey George not sure if you have come across this place I found them in my searches they have some cool stuff and they are actually in Canada.

    http://www.professionalplastics.com/ACRYLICSHEET-DECO
     
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  23. falcongeorge
    Joined: Aug 26, 2010
    Posts: 18,341

    falcongeorge
    Member
    from BC

    Thanks K13, yes, I found that in my searches, they don't show much in the way of pinks on their website, but that doesn't mean they don't have it. After the holidays when things settle down a bit, I will contact them directly. The car is going to be mid fifties Lincoln Amethyst with a white interior with pink piping, if I can find the materials, I would like to find white and pink and a thinner piece of a pale lavender plastic, then make a sandwich with white in the centre, the thinner lavender, then pink, then maybe a really thin piece of white on the outside.
     
  24. I would be interested to see if they have and scraps stuff they sell because it looks like they sell most stuff in 2'x4' sheets. That will make a LOT of knobs:eek:.
     
  25. falcongeorge
    Joined: Aug 26, 2010
    Posts: 18,341

    falcongeorge
    Member
    from BC

    Yes. I just dug a little deeper however, they are not actually in Canada, or it doesn't appear so. I know their website gives that impression, but it looks to be a bit misleading. When I enter my postal code in their location search, it directs me to a location in WA state.
     
  26. Yeah I noticed that as well. When I saw that the minimum order for Canada was about 5 times that of the U.S. I looked at it a little closer.
     
  27. patterg2003
    Joined: Sep 21, 2014
    Posts: 864

    patterg2003

    Some of the fancier materials are similar to those sold by knife making supply companies like Texas Knifemakers Supply. There are a lot of interesting materials used in knife making. I have turned and shaped pieces in the drill press and like the steady point shown here. I sometimes use the belt sander to speed up the machining on the drill press. Great thread.
     
    loudbang likes this.
  28. Wow, every time threads like this pop up it never ceases to amaze me the talented people that frequent the HAMB!

    @CowboyTed, great write up! Your knobs turned out super!

    I posted a large shift knob I made about a week and a half ago. I peeked in my friend's project car and saw that he was going to need one small dash knob as well, so I decided to make one more to include with the big one I made him for Christmas.

    I had some glued and shaped stacks of plastic in a zip lock bag that I put together and shaped probably about 10 years ago. I had a few different red stacks to chose from to do the small knob. The first knob I made turned out pretty good, except I learned something. Way back when I glued the stack together, I made the mistake of putting a thin piece of clear plastic on the ends of the stack. The problem I've been running into when I make these knobs when I use clear plastic is that there can be bubbles, cloudiness or other glue problems. Not as far as adhesion, but appearance wise.

    The red and white knob turned out great, except you can really see the cloudiness of the glue under the clear plastic.

    Well, I didn't like that, so I decided to make another and not put the clear pieces on the end. As (bad) luck would have it, I'm completely out of white squares that were big enough to make this size knob, so I dug around in the zip lock bag again and found a shaped stack that was red and black instead of red and white. I went ahead and did my shaping, sanding and polishing, and I think it turned out ok. I had to really hustle and get it done as Christmas is just a few days away, and I knew I wouldn't have time to finish it after tonight.

    So, here are a few pictures..........

    IMG_2178.JPG

    From left to right: The piece with the paper on it is a shaped red and black stack. The next is the finished red and black knob. The middle is the red one with the cloudy clear top. The blue and the turquoise are original Cal Custom teardrops from way back when. I also included a penny to show the size, and next to the penny is my template for dash knobs.

    IMG_2179.JPG

    This is a side view of all the knobs and the template. I don't understand why, but the camera made my knobs look like they are lopsided--optical illusion I guess (lol). You might notice my knobs aren't drilled to mount yet. I'm going to have to wait to see what size hole will be needed to mount them in my friend's car.

    IMG_2181.JPG

    These are the completed knobs next to shaped stacks. This gives an idea how much material is shaped away to get the nice teardrop shape.

    This has been a fun thread. Sorry if we all hijacked your thread @Barn Hunter. Thanks for starting it! E
     
    Last edited: Dec 23, 2016

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