Harmon Collins Rotors ?????

I know you all have been waiting patiently for me to finish the rotors up, and wanted to post the progress. I'm hoping to get some time this week with the injection mold machine and wrap it up, meanwhile, I had to remake custom rivets that hold the terminals down, make ANOTHER mold (shown in attachment) to stamp out the spring copper contact. (Not regular copper either)

And, another mold to stamp out the brass (Low resistance brass BTW) contacts. Now that that's all done, we are ready for production/assembly!!!

The real dirty moldmker picture is a fine wire that like a bandsaw, electrically extracts material away with high precision. The cncmaker picture is the other machine also with high precision electrically 'washes' away the "Swiss Steel" (what the molds are made from) cha ching $$$....not cheap stuff.

enjoy :o
 

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I personally would not let those who may be impatient to get these rotors rush you along on this project. I would say take the time you need to do this like you want to see it done. No one will probably remember if it took you, three months, six months or longer to get this made right, but on the other hand, if they don't turn out right, they will never forget. Just my opinion. Thanks for taking the initiative do something like this that has been needed for a long time.
 
Hi Guys!


Happy New Year.... well, see attachments, I think they came out pretty nice! the rivet on the right gets sheared down today and stamped down finalizing these puppies. Each (4) piece mold extract takes 7 minutes for ONE injection cycle with this Bakelite. Since I didn't want to alter the original design, they came out of the mold with difficulty. I only managed to produce about 85% and the rest needed to be chipped out due to the angles in the original design. (too straight)
:o
 

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I have no use for these in my applications, however I want to take a moment to thank-you for stepping up to the plate to help those of us who do need these.....I applaud you...Thank-you.........Matt in Alameda
 
An outstanding effort, well done!

Are you able to install Ejector Pins on your mould to help remove the parts without damaging them. I may be talking thru my hat as I'm not familiar with Injection Moulds, but I have done a lot of Drop Forging, and on some dies the only way to remove a forging is with Ejector Pins.
 
Fe26 said:
An outstanding effort, well done!

Are you able to install Ejector Pins on your mould to help remove the parts without damaging them. I may be talking thru my hat as I'm not familiar with Injection Moulds, but I have done a lot of Drop Forging, and on some dies the only way to remove a forging is with Ejector Pins.
Click to expand...
Only from one side, can't have them on both. Because bakelite is higher temp, the expansion and contraction leaves me at the mercy of the parts and mold sides. after the fiirst few came out ok, following ten were chipped out....then by some act of nature, they began to comeout ok.
 
Interesting. Most of the pictures show the "top" side of the rotor, the one with the ejector pins. The fins on that side look to have very little draft. Is that the feature that's hanging up in the mold? There was one picture back at the beginning of the thread showing the "bottom" and the bosses there appear to have a heavy draft angles on the outside. They shouldn't be causing problems. Are there problems with the ID's in those bosses?
 
They look GREAT! Sorry you are having trouble getting them out, but you will figure it out Im sure! I am ready when you are----Thanks
 
PeteVS said:
Interesting. Most of the pictures show the "top" side of the rotor, the one with the ejector pins. The fins on that side look to have very little draft. Is that the feature that's hanging up in the mold? There was one picture back at the beginning of the thread showing the "bottom" and the bosses there appear to have a heavy draft angles on the outside. They shouldn't be causing problems. Are there problems with the ID's in those bosses?
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The issue was with the amount of interference (When heated would get tight) with the brass tube (inside the bottom boss) ID/mold. The bottom half would stick in the mold. Dissimular metal expansion coefficients. There's no draft in the inside of the tube. Tube being the brass piece that holds the bottom side carbon contact and spring.
 
Turlock swapmeet is coming up...I'm not too far away, and will be in Turlock on Sunday of the meet (but not at the SM)...anyway, if anyone going there, and assuming DF has some ready to go, to save multiple shipping cost he could send them to me and I could deliver on Sunday, if it helps someone save a few bucks here and there, as I know a lot of Barners go to Turlock.

Just trying to do my part to help!
 
Ladies & Gentlemen, you asked for it - ya got it! Here's the first rotor off the production table. I will continue this week and see if we can start shipping end of next week. PM me if you'd like a pair. (Gotta sell in pairs....i'm a Po' boy ;)

ENJOY...
 

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