!914 Twin HD Cannon ball request

[c.o.]

Hey Joe,

Are you too picky? I don't know.... it's your bike and if you want it finished a certain way then it's not being picky... it's about doing it right...

I've not had as much time to work on the '48 as I would like but things are being figured out and it should be up and running by the end of the month... I hope I didn't just jinx myself by saying that.......

Here's some pics for everyone's viewing pleasure....

[c.o.]

[gary.h]

i just love looking at these pics especially,when you see hand crafted metal bieng applied to old parts and seeing them combined together,it gives you a subtle outlook that when these machines are in the right hands can become immortal,just takes time and passion,looking great joe!!and as for your 48 cory,it needed to find you its in a good home now!

[Slojo]

Screwing Around

After visitors drove off today I was back at it. This time the CNC lathe was calling my name. I finished a program and set-up that was already in process, for the sole purpose of making Fillester head screws from pre-heat treat 4140 steel. This will give me the equivalent strength of a grade eight bolt except the screws will be fully machined instead of cold headed and thread rolled as new bolts are processed. I still plan on checking out a lead on an old bolt shop that I just learned about.
The eight inch chuck is a little impractical for holding onto the 3/8 inch stock and a better set of chuck jaws or a collet system might have to be put in place of the chuck to process this small bar stock and part. For now I will attempt to produce good parts with the chuck. Currently with one fair prototype of about five attempts more improvements will need to be made to process a good quality screw. If this process works a milling head will be installed into the mix to cut the screw slot in the head so a finished part will fall off every time the green button is pushed. Cycle time will probably be around one to two minutes. The primary difficulty is dealing with the length to diameter ratio of the screw. right now the screw being made is for the clamp ring on the Freewheel clutch throw out bearing 1/4X24 x 1 1/2 over all length. I am afraid I may need to add coolant to this process...what a mess.
Joe

[c.o.]

[c.o.]

i just love looking at these pics especially,when you see hand crafted metal bieng applied to old parts and seeing them combined together,it gives you a subtle outlook that when these machines are in the right hands can become immortal,just takes time and passion,looking great joe!!and as for your 48 cory,it needed to find you its in a good home now!

Slojo certainly does a good job..... He continues to amaze me with his precision work.

Thanks for the comment on the Pan.... I'll do my best...

[Barry Brown]

Is the head purposely offset? Will you be heat treating these bolts? Just curious.

[Slojo]

Barry
The offset head is important to allow me to bolt the misaligned gas tanks on to the bike. Actually that is a result of the bent bar and the way the part is processed right now. I am working on a resolution for the problem. The material has a lot of resistance to cut with the small diameter it tends to push away from the cutter, with the slightly bent bar it causes the push away to be uneven as it revolves. The material is pre-heat treated 4140 about 35 Rc and will require no further metallurgical treatments other than plating
Do my best...? the screw is not pretty at all vet, just taking shape at the moment. Chatter issues on this long, small diameter part are a problem coupled with a slightly bent bar, how did that happen?
Joe

[Slojo]

I am processing the bolt backwards so the end where the thread is cut will be nearest the chuck for rigidity. This way the head end will be exposed so the slot can be milled in the same operation as the turning, a complete part in one operation. A machine operation must be tuned just like a motorcycle engine and chassis to get the desired results.
Joe

[Lonnie]

Joe, I am curious, are you tracking the man-hours on this? It would be interesting, and eye-opening!

[Slojo]

Screwing around

Lonnie
I have not tracked the hours invested in this build but could calculate a close guess based on the time line that I have been working on the project. Last night work progressed on the fillester head screw project . Tuning this machine operation is a bit troublesome. Some times its difficult to comprehend what actually goes into a bike build, two days so far just trying to produce screws.
Joe

[chas]

Joe, perhaps a slight radius at the offset on your bolt would be a prudent precaution? I just hate seeing notches in high strength steels no matter what the load.

[Slojo]

Charley
Once this program is finished there will be no tool marks, no offsets and a nice under head radius of about .030 ". Relax all is well.
Joe

[Slojo]

Still screwing around

It is in my best interest to get this program worked out to perfection. It is nearly complete with just a little more tuning and then the finishing touch, the addition of a slitting saw to put in the screwdriver slot. Currently the cycle time is around 2.5 minutes without the slot. There is excess cycle time to reduce in the process and that will be addressed soon although the importance of cycle time is second to quality. My style of programming used on this part is once again a universal program allowing me to change the entire nature of the screw with just altering the ten variables required to define all the dimensions of a basic fillester head screw. Once complete any fillester head screw should pop off the same bar stock with five minutes of preparation.
Joe

[Slojo]

It appears that either alternative tooling or a piece of polishing paper will be required to produce a satisfactory finish on the body of the fillester screw.With a six to one diameter to length ratio vibration (chatter) results in the finish of the work piece. This particular screw is for the Free Wheel clutch adjusting clamp ring and is just the beginning of the hardware that will be produced for this cannonballer bike. A few extras will be made for those who have a need for the same item. This part has consumed to much time to develop into a good process fortunately the procedure can be used for future hardware soon to be produced.The following video demonstrates the process used for producing this screw. Cory has a photo of a finish turned screw perhaps he can post it tonight for us, it has had a slight pollish on the 1/4 body.
Joe
http://www.youtube.com/watch?v=cqc58JQ7F2Q