Technical INTERIOR, Laminated dash knobs

My first attempt at tech,so bear with me.

I know you can buy them, but I don't really care for the clear in the center of the bought ones and making your own will add another touch that makes your car"yours"
Alot of you probally know how to make them, but if you're not sure, here's how.

I'll start by listing the supplies/tolls needed for the job.
1.1/8 in.plexiglass,acrylic or lucite,in whatever colors compliment the interior of your car.My plastic supply house has a binfull of end pieces, cut mistakes,scrap Etc. that I buy out of at a big savings over having them cut me some off a full sheet.
2. Adhesive."Weld on" #4 water thin,for acrylic.available at plastic supply house.
3. polishing compound. For acrylic. I use Dico brand. also at plastic supply house.
4. Acid brush. for applying adhesive.
5. scale (ruler)
6. a bandsaw with a fine blade. Too aggressive a blade will chip the plexi.
7. a table saw with a fine blade,not really necessary but it makes cutting down larger sheets a little easier.
8. a belt sander with an 80-100 grit belt.
9. a buffing wheel.
10. an assortment of sandpaper,40-400 grit.

Leave the protective paper on the sheet and draw a grid of 1 X 2 in. squares on both (colors) sheets of plexi. This is a good size for dash knobs, shift knobs should be a little larger.
Cut the squares out on a table or bandsaw.
Note: The reason for cutting the plexi. first is, then bonding, as opposed to bonding large pieces together then cutting them into smaller squares, is that the adhesive dries VERY fast and both pieces must have a wet wet coat of adhesive when stuck together. Very hard to do on large pieces.

For this example I used red & white. 7 pieces will make 1 knob, 4 red, 3 white. i start by lining up the squares in alternating colors to make 1 block. I then pull the paper off one side of red & white, apply adhesive to both pieces with an acid brush and quickly press both pieces together and hold for a few seconds while they bond.
Then pull the paper off the other side of the white and one side of the next red piece and bond the same way you did the first till all 7 pieces are bonded together. Wrap the block in a rag & GENTALY clamp in a vice for for 10-20 minuites to ensure a strong bond.
Note: The reason for leaving the protective paper on the pieces till just before bonding is to keep dust & the oil from your skin off the surface as it makes for a weaker bond, and you still want paper on the outside of the block.

Now I've got a laminated block with paper on each side. Draw out the basic shape of the knob on the paper. I chose a teardrop for this example.

I cut the shape just drew out on the bandsaw.

I then fire up the belt sander and work the piece to get it as close to the final shape as possible. Keep the piece moving and dont exert tooo much pressure, let the belt do the work & be patient. It takes me about 10 minuites to shape a knob on the beltsander. When you're done with the belt sander, if you have a few spots of melted acrylic The 40 grit will knock them off quickly by hand.
Now it's all hand sanding the knob up to 400 grit & you have no scratches. The finer grits you can water sand the knob.

Next step is to laod up the buffing wheel with the polishing compound, hold the knob tightly and keep it moving over the wheel. It will polish up quickly & without much pressure.

Now you can drill it and mount it.

Please let me finish posting photos before commenting or asking questions. I know it was kinda long winded but i wanted to add as much info as I could.

Billy

The supplys you'll need.

 

block bonded & basic shape cut out on bandsaw

 

After shaping on the beltsander

 

Final sanding with 400 grit paper

 

Polish it.

 

The finished product, ready to be drilled & mounted. The end.

 

Tech week RULES. Awesome post and pure genius.

-Dane

 

Very, very nice Shoebox72.

Haven't seen these done in a long time.

I would like to make one small recommendation if I may.
Drill and tap prior to buffing.
I do a lot of aluminum and brass stuff and if they are drilled & tapped prior to buffing and a bolt installed for a handle, it's a lot safer as pertains to the buffer grabbing it and flinging it off into the shop somewhere.
Just be sure to buff on the "tighten" side of the threads so you don't unscrew it with the buffer and lose it.

If you mount a headless bolt into the goodie you can use it as a mandrel on a drill press and perhaps do some additional shaping there.

Regardless, good stuff.
Gets my vote....

 

wicked!!
Im doin it.
one question..what is an acid brush?is it resistant to the glue?

 

Thanks, this is a great tech post!

Justin

 

Great post!
I might have to make me some knobs for the Olds.

 

Cool man reminds me of Jr High we would make those in the 70s. Damn I am dating myself. .Danny

 

[ QUOTE ]
..what is an acid brush?is it resistant to the glue?

[/ QUOTE ]

These are the cheap disposable brushes sold for applying flux when soldering Copper pipe.
They are made from Horse hair,so solvents won't disolve them.
Probably each 35 cents in the plumbing section at Home Depot.

 

My only question is where to find a plastic supply house?

Can't seem to find one locally...

 

"Tap, Tap Plastics"

 

What size block(in inches) to make a shift knob? like 6" X6"?


Thanks,

steve

 

Awesome post, i saw this in a old car mag and was thinking about making a few tonight! Nate

 

Thanks for the compliments guys.

C9, Thats a good point you bring up about drilling them before polishing them. I should have recomended that but in my case, I make them at work (don't tell my boss)and bring them back to my garage and drill/tap to fit for each individual application. Also, taping for a screw to use as a handle is a good idea cause they will launch pretty hard if you don't have a good grip on them while polishing.

Try looking in the yellow pages under plastic suppliers. I get my stuff from Modern Plastics, Bridgeport CT.

Billy

 

Cool...We used to make those in my high school wood shop class..I think I'll head over to TAP this weekend..

 

Rat, I'd recomend 2X4 inch max for a shift knob. Regardless, it should be longer than wider or it will look like a popsicle.

Thanks, Billy

 

.......VERY cool!

 

Very cool! I knew the information, but it really does help to SEE it done and get all the helpful little hints, too!

 

Very cool, Great Post! I'm going to try it!

 

We used to make clear layered ones in crafts class in high school.

Diggin through the memory banks here, but it seemed the glue used was Duco - a clear glue - and it was colored with I believe food coloring. Maybe not, not real sure there.
Nice part was, the colors - usually red, blue & green, sometimes gold - looked like candy apple once the plexi was buffed to a clear finish.

We also made some plexi goodies that went into a pan of boiling water that had food coloring in it.
The colored water would permanently dye the plexi.
Longer you left it in, the deeper the color would get, but you had to watch it cuz too long and some projects would sag out of shape.
Made a cool rose colored letter opener for mom that she still has. All I had to do to it to get the color was dip it several times for a few seconds each.

If the glue wasn't Duco and if food coloring was not used in the glue, I'd appreciate hearing just what was used.

 

Great post shoebox72! I make my own teardrop knobs too. I thought about doing a post on it during the last Tech Week, but I knew it would take alot of work!

I have a few tips that might help out some guys that have never tried this before. First off, make a template. To do this, you need to take one of the extra squares that you cut out to make a stack that will become your dash knob. Be sure to LEAVE THE PROTECTIVE BACKING PAPER ON! Use two round objects (size will depend on what size knob you are making--more on that later). You can use a drill gauge to figure size, or if you don't have one, any round object will work in a pinch. One must be larger than the other--like a dime and a penny, or a nickel and a quarter. Center the objects at both ends of the square and trace around them with a pencil. Next, take a ruler and make a line connecting each circle on each side. You will kinda start to see the teardrop shape. Now, take the piece of plexi over to the belt sander and grind it to the lines. There you have it, a teardrop template. You might want to mark it so you know that its for a dash knob, shift knob, etc.

The sizes I use are as follows:

1 X 1 1/4 inches for window rollers and door handles
1 1/2 X 3 inches for gearshift knobs
1 X 2 inches for dash knobs
3/4 X 1 inch for heater knobs

These are the sizes recommended in the article I learned from. The sizes work well, but you can make them any size you want. If you're still not clear on how to do this, look through your magazines or ask to borrow your buddy's copy of Custom Rodder, Spring 1993, Volume 3, Number 2. There is an awesome article on how to do this--like I said, this is what I learned from.

Alot of you guys out there may want to try this, but think you don't have the right tools. You really don't need that much. If you don't have access to a belt sander, you can do what I did. I have two variable speed buffers that I mounted to a 2 X 4. I laid the buffers on their side and made a mark on each side of the buffer at the top, middle and bottom. Then I drilled the holes out and used heavy duty zip ties to secure the buffer to the wood. Make sure they are tight. You don't want the buffer to move around on you. A runaway buffer is VERY DANGEROUS! (If you have the money, a bench grinder will work for this as well. A light duty one at Wal-Mart, Lowe's, etc. will work fine, and they're not that expensive. Usually around $50.00. Just make sure you're equipment is SAFE!) After you do this, you clamp the wood in a vise and you have a portable sander. I use a Black and Decker Workmate and it works well. Each buffer has a rubber backing plate mounted on it and then the grinding disc. One has a 36 grit disc, the other is a 120. The 36 is for the profile, or basically it makes the teardrop shape. The other is to give the knob the "egg" shape. That is the trickiest part. You have to keep rolling the knob or it can get a goofy off center shape. It takes practice, but once you get the hang of it you'll be able to make knobs in no time. You could use a rougher grit for this step, but the time you gain by removing the material faster is lost again when you have to sand out the scratches. After the shape is set, I get some 220, 400 and 600 wet/dry sand paper and go to the kitchen or bathroom sink. I let the water trickle out of the faucet and sand away. A few minutes on each grit does fine. Keep checking the knob wet to see if there are any more scratches that need to be sanded out. After you're satisfied there are no more scratches, dry the knob off and get ready to polish. For polishing I use a Dremel and jeweler's rouge. On the Dremel, I use the little cotton(?) polishing wheels you can get at Wal-Mart, Home Depot, etc. I buy GREEN jeweler's rouge at the local truck stop. You can get a big brick of it for 5 bucks. It goes a long way. There are three different colors (white, red and green), but I've found the green works the best. It shines nicely without getting too hot or being too abrasive. Ok, take the Dremel and set it a 2 or 3. Not too fast, its easy to burn or melt the knob. Once you burn it, they never look shiny on that spot. I've tried re-sanding, polishing, etc. and nothing works. It pretty much ruins the knob. With the Dremel running, load the wheel with some rouge, and without much pressure, run it back and forth. Front to back is easier than side to side. Let the Dremel do the work for you--take your time. You'll start to see the dullness from the sanding going away and it will start to really shine! Don't let the polishing wheel get too "dry". Keep the wheel loaded with the rouge. It's a little messier, but a wet wheel is less likely to burn or melt the knob.

As far as mounting goes, I bought a cheapie drill bit gauge at Lowe's and I slip it over the shaft that will receive the knob. After I figure out what size it is, I drill a hole about halfway through the knob with a smaller bit. When you are starting to drill it, go a little way in and make sure you are centered. Let the knob go and keep the drill running. If it is straight, there will be no wobble. If it is wobbling, you need to stop and take another run at it with a little different angle. If you catch it early enough, you can correct it. Next, re-drill with the same size as the shaft is. After the hole is done, I get a little JB Weld Quick and put it on the shaft and a little in the hole and press it on. This mounting method works on most kinds of knobs, but be sure you want it on there for good, 'cause after the JB Weld goes on, they're tough to get back off. Radio knob mounting is different, but I've used enough of shoebox72 and Ryan's space here. If there is more interest in mounting them on a radio, I'll post more later.

Sorry shoebox72, I didn't mean to jack your post, but I really enjoy making these knobs and it's something that I actually know how to do! Just my little contribution to Tech Week.

 

In additon to this post, it would be cool to see some that other HAMB'ers have made. pics??

 

<font color="brown"> Great post!
I spent a few years in the sign industry. The fabrication department adhered the acrylic plastic with a solvent called Methylene Chloride. We used a glass syringe with a ground off needle.
This works extremely well and does a great job.
Any sign fabrication or plastics shop should have scraps, red, white, black along with clear being most popular for memory.
I have stack loads of it if any Kiwi Hambers need any.
Cheers,
C
</font>

 

[ QUOTE ]
In additon to this post, it would be cool to see some that other HAMB'ers have made. pics??

[/ QUOTE ]

Im going to make 2 or 3 today... depends on how long the glue takes to dry...

 

You can also use your oxy to flame pollish your plastic. Set it to a soft flame, Like a bic cigerette liter makes and gently wave the flame over the acyrlic with out setting it on fire. It takes a little practice (about 5 mins) but when you got it worked out it saves a shitload of hand pollishing.

 

thats exactly how i made the ones on my ute. i remember the first attempt at shaping one on the sander, it shot across the room and broke in 2 on the floor. i held on a bit tighter after that
craig