Does anyone have the specs for the 917 shift knobs? I am talking about the ones that were laminated wood.

I am looking for:
What wood was used in the lamination
What are the dimensions
How was it attached.

I know someone already makes these, and I could just buy one. However, I am interested in learning how to use a wood lathe and my grandfather is going to give me his and all his tooling for it. Instead of just turning eggs until I get the idea of what I am doing, I figured this would be a more useful project to start with.

Zach

Hi Zach. We have one here in the showcase

Zach, post a picture.
It might be either rosewood or mahogany...gotta see it.
You can use either, both will gum up the tools.
First thing to learn with a lathe is how to hand sharpen the tools.
Its really important to learn this...
Rusty does pens..he can walk you through the sharpening process, or I can....dont use a machine, use oil stones, old school.
I have tried all the new fangled diamond stuff...oil is better for a razor like sharpness.

For the shape, you will have to take pretty precise measurements.
Quick and simple to do with a contour gauge, then trace that onto a piece of paper.
So, you could take the gauge into a car, get the contour, then trace it on the spot...fold that up and be on your way.

Mounting should be similar to the stock on.
That is a hole of dimension X and buy a new jam bushing to insert into the base of the knob.

Rich

Neat!
Any chance I could get you to pull some specs off it for me? Maybe some reference photos? I'm not planning on making these to sell (don't want to step on toes) but I'd like to have a better idea of what I am making.

Zach

Rich, I don't have any pictures of the original ones. I don't want to work off the repoped products if I can avoid it. Hence the call for specs and pictures, etc.

Zach

Well a balsa shift knob, was made of balsawood

the Porsche Carrera GT has an shift knob in balsa.



917 version is more "ball"shaped
This is the best pic i found from a 917 cockpit

I would be interested in the specs as well. I have also considered making one for myself.

If someone could post a link to whoever makes repro version today, that would be helpful as well.

Looks like a laminate glue up with 2 types of wood. Balsa is pretty soft. I would think you could use just about any wood you wanted as long as you liked the colors.

I thought it was clear pine and magohany. Balsa is to soft to hold up to the handling. Thomas has one and I'll take a look at it for you Zack.

no not balsa. The one we have is original old stock so I think. I will take a pic in a moment and post

huge bird thread about them;
http://forums.pelicanparts.com/showthread....alsa+shift+knob

here a pic/sale
http://www.tremotorsports.com/product.cfm?Node=10299

Zach,

If you make a couple, I'll take one. I have a shifter for the red car that doesn't have a knob. Those 917 knobs look cool.

Spoke

I do not know how to down load the image from my e mail! Sorry Jason is not here today so I need some help

Open email.
Look at picture
Hover mouse on top of picture.
RIGHT click once on the mouse as its on top of the picture.
Left click, save attachment
Save the picture to /mydocument/pictures
Now you have it.

Rich

like this

Maple and mahogany.
1/8 inch maple
1/4 inch mahogany.

Hint.
Make a long laminated glue up that is 1.5 wide (if thats the width) and 2 feet long..
After its dry, cut a bunch of square blanks for the lathe process.

Another hunt for the learning curve
Go buy a fugly cutting board at a kitchen store made from these two woods, maple and mahogany
Cut a few square blanks and turn up a few practise knows to get a feel for how fast you can cut, how to mount it etc etc.

You will end up using a custom made deadman for the non driven side of the knob...not the pin it comes with.
You turn that up out of rock maple or any super hard wood..rock maple is easier to find.
It will be shaped like a cup, but very shallow to give you room to work.
Use soap to keep it from burning.


Rich

As I don't have a plane or a bandsaw to make the thick boards thinner, where can I find mahogany and maple in 1/8 and 1/4 inch thicknesses?

Its easy in balsa or pine, but I was unable to find it in other woods.

Zach

My dad does abunch of woodworking, If you want some catalogs let me know. He gets woodworking crap as often as I get car crap.


http://www.woodcraft.com/depts.aspx?deptid...amp;topnav=true

here she is

Um no. Bad monkey, bad. Go to your poop box and think about what you have done.

Okay, we have some people saying that they are balsa/mahogany and some saying that they are maple/mahogany.

Can anyone point me to a source that says definativly what they ware made of?

I can't see how balsa would deform when laminated with mahogany.

Zach

Purple heart and Cocobolo

From messing with model airplanes as a kid, balsa wood is so soft it would probably split apart while machining and that would be really frustrating learnig curve.

The 917 Shift Knob is actually made from turned Birch Plywood. How do I know his. Hans Metzger told me. Balsa would absorb moisture like a sponge and crack as it is very porous. The shift knob was never intended to be light weight. The purpose of the wood was because the linkage transmitted so much heat from the transmission into the drivers hand that wood was used as an insulator.

I got 2 of them from Mark Cross when he was making them several years back...He may still be making them, I don't know.

I'll take pictures and measurements of mine later today if you would like.

The link to the 911S registry story is:


http://www.early911sregistry.org/forum/sho...ight=shift+knob

His email was (is?)
macross860@columbus.rr.com

David

same person as my post, he sells exclusively to TRE, wich is in the post also.

I got one of Mark Cross' knobs back when he sold them for like $35. Here is a pic.

Click to view attachment

They weren't balsa.
Here is his post from when he was selling them. It might say what he made them out of. I didn't review it.

http://www.914world.com/bbs2/index.php?sho...&pid=248306

How did you get it on he Rennshift? That looks great.

You know, I was able to find a factory Porsche crush sleeve. I tried to use it, but it took more pressure than I was comfortable putting on that wood shift knob. If I would have split that knob putting it on the shifter, I would hate myself. So, I cheated and I just used duct tape to act as a bushing between the shifter and the knob. Wrapped the shifter with the duct tape, pressed the knob on. Its a dirty secret but it worked.

Consider that a "Duct tape confession".

On the TRE site they say to glue the knob on to the shifter arm.

Zach

Although I saw this thread I never looked at it, to me who would want a knob made of balsa. Too soft and would look like crap in no time.
Also it has to be to hardwoods, as a softwood and a hardwood would be hard to machine and almost imposable to sand. The softwood will sand more than the hardwood making it rippled.

Birch ply could be correct as the Germans loved to use Baltic birch ply.




Now that peeks my interest...and I have a huge board of purple heart.

How about purple heart and black walnut or cherry
Maybe purple heart and white ash

Maybe purple heart and white ash
[/quote]


OOOOoooohhhhhhhh I'll take one please

I thought the big board was purple heart, but now that I've looked it's more likely Pernambuco and I do have some pieces of amazon rosewood

A good "type of exotic wood" site is this one:
http://www.hobbithouseinc.com/personal/woodpics/

Well, I bought enough mahogany and maple to make 3 or 4 knobs.

I could not find birch plywood - but I did not look too hard.

So, I guess the idea of the "balsa" shift knob is just a well accepted myth?

Zach

Good grief, pay the $75 and be done.

If I did that, how would I learn to use a lathe? If I wanted to just be done with it, I'd use the cool aluminum one I have on hand.

Zach

Mahogany and maple glue up.

in trimmed specs are about 47mm tall x 50mm wide.

Starting with 5 of them. I have enough mahogany for 1 more knob, and enough maple for 2 or three. But I am out of clamps and got tired of cutting disks. So, starting with 5.

Pics!




I'm at the in-laws this weekend due to the house flood, so I only brough hand tools with me. Was really relaxing to slow down and just use a coping saw for a while. I'll leave them in the clamps over night and start turning next week some time.

Zach

Finish your dang car already

It bugs me when people tell you to take the easy way out, kind of misses the whole damn point.

Next weekend.

I may be able to sell a few of these at Hershey to recover some of the money spent on the house this and next week. Sides, while I'm at the inlaws, not a lot of car work I can be doing.

Zach

The high road taken has the better view!

PROGRESS!

Okay, my grandfather, who owns the lathe that I was going to turn these on, has been hard to schedule time with. For a 94 year old man, he is busy nearly every day. The other side, though, is that he gets tired very quickly. Its important for me to spend as much time with him as I can, while I can.

But, long story short, I had time last night, so I made this without the use of a lathe. I used to do a lot of wood carving, so I carved it. I did most of the shaping with a 1/2 round cheese grater type file, and then chucked it into my drill press for sanding. I raised the grain 3 times, and the last sanding was at 400 grit. It is baby butt smooth. Then I threaded the aluminum shank so I could screw it in to my Rennshifter.

it is not *perfectly* round, but it is pretty damn close.

I think that I will finish it with some boiled linseed oil, or maybe tung oil. Something that will deepen the color and natural luster of the wood w/o staining it.

Pics!
I still don't have my good camera. I took this one at my office with a P&S, then fixed the white balance in photoshop.


This really bad picture was taken with my cell phone. Please excuse its crappyness.


Due to the fact that I threaded the shank after I made the knob, I'll need to add a small aluminum spacer between the knob and the shifter, or drill out the first 2 or 3 threads in the shifter. Right now there is a 1/16 inch gap between the ball and the shifter. I did not want to thread the shank before I glued it in place because I was worried about damaging the thread when the shank was chucked into the lathe (or drill press in this case).

I am going to make 4 more of these, using the lathe. Again, its more about the time with Pop pop then the need to use the lathe, but learning a new skill is always a plus too.

Zach

Oh! I forgot to add the ball specs.
it turned out (get it, TURNED OUT! HA!) to be 46mm wide by 47mm tall.
The ball (and shank, obviously) weighs 39 grams.

The turned aluminum knob that I have weighed well over 100 grams, and I thought it was light. My reloading scale only goes to 100 grams, so I don't know exactly how much more the aluminum knob weighed, but it was considerable.

Zach

Nice work Zach!

Nice work. If you want to sell one of the extra ones, I'll take it. I'm converting my red car to side shift and the shifter doesn't have a knob.

Spoke

I'm not sure what I am going to do with the spares. I know I am going to sell some of them to recoup costs for the project, but I am not sure if I am going to make them all into Rennshift balls, or if I will want to make a jig to turn them for the standard shifter (which I don't think will take the shank). Right now the shank can be used to attach the ball to the lathe with a standard chuck. Without the shank, I'd have to make a special jig to turn them.

I am sure that I will have at least 2 for sale at some point, maybe 4. It depends.

Zach

Nice work sir. Very attractive.

very nice.

Please let me know on the extra ones as well... I am interested

Nice work

That is fantastic and a really beautiful looking thing!!

I would love one too - s If you fancy having one residing in the UK please let me know..

I would really love one of these in the '14 so If you can't manage to save one for me, is there anywhere in the US that manufacturers them?? (I guess not as you are doing it yourself )