I said I would do a tech piece on how I made that 4 spoke banjo wheel. I made a three spoke this time but the method is the same. You could use the same technique if you wanted to "regrip" an old wheel that is all cracked or has no grip left. First I started with a piece of MDF 2' X 4' and marked a line to split it in half..... Next I cut the pieces and stacked them on top of each other and marked a center point and four bolt down holes and one register hole (to make sure the halves go back to the same place.) Then I marked the two halves with arrows so I really get them oriented properly. Next drill out the holes...!/4 for the center hole and 3/8 for the others The next step I did was use a holesaw to make the center bigger so I can put the halves on my rotary table on my milling machine but if you only had a router you could use a circle attachment to do the same job. Because I want the grip to be 1 inch I bought a 1 inch round router bit and chucked it in my mill I set the bit 7-1/2 inches from the center of the rotary table and that gives me 16 inches to the outside diameter on the wheel I set the depth at 1/2 inch and started turning the table Once I made a full circle I went over it a couple times to work out the machine marks then I set the depth stop 1/8 inch lower and started to make the nibs. My rotary table is 90:1 turns /rev so I made a cut every 2 turns of the handle ...works out to 45 nibs. It really helps to have an "easy button " on your machine I can use it on all my machines since I put a magnet on the back The other half of the mould is just a groove without the nibs, same procedure so now we have two halves So , here's where I make the wheel part. I machined a hub ( to fit on a three bolt Grant adapter) and cut the spokes... Assembled the spokes and welded them I had a friend with roller , roll me a 1/2 mild steel rim and I welded it to the right diameterThen I welded the spokes and rim together Next step is to prep the mould. I sanded the inside progressivly up to 320 then applied Minwax paste wax to the inside as a release agent. The scary part comes now....I mixed up about a quart of short strand fiberglass filler . I added some fiberglass resin to help it flow a bit better and I also mixed in some black fiberglass resin pigment. Make sure you mix up enough,,,,maybe even mix a little too much. I didn't mix quite enough and had a couple small voids. Not a huge deal but it would have been nicer to not have to fix the pits. Anyway take your mixed GOOP and fill both halves of the mould. Once they are full , set the rim in place and then mate both halves of the mould and bolt and clamp it together After the GOOP hardens you can carefully seperate the halves and you should have a steering wheel. Mine is not finished at this point. I still have to fill the voids and sand , prime and paint the wheel but you get the picture I hope. Now I'm sure that there are guys who know alot more about resins and casting and such and I hope they chime in with comments. I don't know how this filler will stand up to hot/cold cycles but in total it cost about 50 bucks for all the materials . I checked the Summit racing catalogue and banjo wheels in there are in the $300 + range so you do the math....anyway, it was a fun project!.....don't forget your "EASY" button
That's a really cool project. Have you done casting like this before...how'd you come up with that method, it's pretty creative. Thanks for posting. (Is there any thing needed to hold the spokes to the hub?)
Amazing! How did you get the goop into the mold? How did you center the metal in the form? Very Impressive!
i dont know why i bother. thats why i love this site. i would love being able to go buy stuff. just as much as i would love being rich. but then i get on here and see how to make almost everything. just waiting for the "Look how i casted my own WWW's". thanks Jethro.
The spokes are welded to the hub, I'm sure. This is a great example of ingenuity and rodding technology. Super job, friend.
Thanks for the compliments guys! This is the second one I've done ,but no other casting experience...just making it up as I go.The spokes are an interference fit to the hub (had to pound them in) the welded rim assures that they won't come out.
Crap, that's nice! You could just wrap that with leather or something and not worry about the voids. Looks great.
The GOOP is basically shovelled in with flexible putty knives...that way you can "smush" it into the mould. I cut the grooves for the spokes so I can get both halves tightly together.
Brilliant! this would be a good way to redo the grip on an old banjo that's seen better days. or custom make a bell style 4 spoke. smooth-on offers a variety of resins and mold making supplies and is an overall good resource for casting and molding. http://www.smooth-on.com/
Nice job !!!! Thats some talent . Wonder if you could use that liquid rubber the stuff that they dip tool handles in ??? Maybe it wouldn't get hard enough. Rocky
Jethro---Very nice tech article!!! I'm not sure how the filler will stand up, but it is tougher than whalebone, and "Nothing ventured, nothing gained"!! very nice.---Brian
WOW! I am constangly humbled by the imagination and creativity here. That is, hands down, the coolest thing anybody's posted for a while. Great use of Bondo too! I had the '48 Pontiac banjo wheel in my Chris Craft for over 10 years, and it's just patched with short strand filler and bondo, and only tep small cracks, I'm sure where some of the original plastic is still shrinking. Your's should be good for decades. Brian
sweet..nice tech..Hey..I have one of those Easy buttons too.., but since i got it nothings been easy.. fuckin great now i gotta fix my dam easy button too?
Nice job! One way to possibly avoid pits and voids is to somehow hook up a vacuum source to it. I have a customer that pours silicone forms and sets them into a vacuum chamber to suck the bubbles out of the silicone. The vacuum chamber isn't anything fancy, just a large piece of PVC tubing with a piece of Plexiglas on the bottom sealed with silicone sealant and the top is held down with a weight until the vacuum sucks it down. With the talents of the guys on the board I sure someone can think something up.
i have watched pewter casting, they used a 12" dia. table spinning at 300 rpm's, you pour the liquid in a hole in the center and it travels out through groves cut into the molds.
Thats it !!! This is the reason (amongest a MILLION others) why I Love the HAMB. It leaves a guy hope. Set yourself to it and it can be done. Oh yeah........ lots of skill!! Yeah!!! You rule!! I ain't worthy!!!!!
Industrial supply houses have a large variety of 2 part liquid rubbers with a lot off different durometer readings. You can use them for different applications where you need to mold your own mounting pads, also would be great for that banjo appication . I can remember back in the middle 40's when the home made steering wheels were wrapped with twine and then numerous coats of shellac and varnish were applied. Gary
....PICKING SELF UP FROM FLOOR.... AMAZING. This post actually inspired me. I need to build ( or at least fix) a steering wheel! KEEPER!