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Post by mhensen on Jan 31, 2016 20:30:10 GMT
Aren't you afraid that that the levers will be to weak with the tubing instead of full metal type...
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Post by GA-Dawg on Jan 31, 2016 22:32:21 GMT
Hi Mhensen,
The arms are the things that I am most concerned about. I have the ability to machine up some billet aluminum ones but that kind of takes the DIY part out of the project. I am open to suggest.
-gadawg
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Post by mhensen on Feb 1, 2016 6:42:17 GMT
I am in the same situation.. thus far I have made everything by myself on the lathe and welded it up... This last thing for me to tackle on the hardware side is the lever..
The keyway is my problem but I saw you were using the power drive H pulley and that gave me new hope... So now I am looking to get them too, I believe I saw them on Amazon..
I will be using 50*25mm steel to make the levers.. that would be sufficient enough, I guess :-) nearly the same way as you but just a thick slab of steel instead of tube..
(Edit: Checked on amazon, but they don't deliver it internationally :-) and shipping from electric motor warehouse would be $135 :-( So back to 0 ) |
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Post by paulg100 on Feb 1, 2016 6:47:50 GMT
based on the levers i had made and the weight of them i reckon 20mm will be plenty thick enough. 5mm will make quite a difference to the weight of the lever.
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Post by mhensen on Feb 2, 2016 16:54:19 GMT
I had made some enquiries here in the Netherlands for making the arms according to my specs.. well that was a bummer!! ranging from 360 euro up to 920 euro for 6 arms..
So now I am thinking of a different and easier way.. I let the keyway out and drill a little hole in the shaft, just enough to get an m8 bolt to get just a few mm into the axle..
 and slice the part with a saw..
it will either be holding based on the friction it gets from the m8 bolt at the end of the bar and otherwise the bolt that goes a little into the axle will hold it in place..Either way there should be no play and it should all be fine..
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Post by paulg100 on Feb 2, 2016 17:18:19 GMT
if your not happy with doing your own i can let you have the details of the guy in china that done mine.
$40 each plus shipping, came to about $440 total for me i think.
about a weeks turnaround plus shipping
Edit: Found email, robinyang89@gmail.com
name is robin, just needs a PDF with dimensions.
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Post by mhensen on Feb 2, 2016 17:26:54 GMT
Thanks but have ordered the metal already.. so I'll try it firs. if it doesn't work I have one more option in the diy section.. If that also fails I'll get back to you! :-)
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Post by paulg100 on Feb 2, 2016 17:48:57 GMT
see if you can use bushings to take the rod arm that goes to heim joint. even with the machinists tollerance of .1mm there is a tiny amount of play in mine, i would have preferred to be none,
thats going to be very difficult to drill holes with an ideal tolerance without using facotry made bushings i think. when you put the shafts into the motors that we got, that is kind of the tollerance that would
be ideal. Spent a bit of time reading up on machining tollerances and that is way less than .1mm.
or maybe slightly undersize hole and eek it out with a drum sander to get a friction fit, or weld the rod arm to the lever arm.
You seem pretty good with metal working gadawg what do you think?
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Post by GA-Dawg on Feb 4, 2016 14:47:35 GMT
Hi Mhensen and Paulg100,
Sorry for not responding sooner.
Mhensen...I would think you should be able to find something similar to the "Power Drive" locally. Lots of the V pulleys use the "power drive" insert. That way they only have to create the one pulley but it can adapt to different shafts as the "power drive" bore comes in different sizes.
Some suggestions on your lever design. I would not drill that large of a hole through the shaft as removing that much metal could lead to a failure. What I would suggest is drilling a smaller hole (4mm) through the lever and the shaft and inserting a dowel pin. But there is a trick that you should follow. This will help insure that you don't have to much movement with the pin. It is extremely important not to have any movement as it will greatly increase the probability that the pin will sheer.
Here is the process.
1. Place the dowel pin in the freezer.
2. Drill a pilot hole through the lever and the shaft.
3. Heat both parts up to something around 500 degree and drill the hole to the final diameter. This will insure the hole is slightly smaller then the expected diameter.
4. While the lever and shaft are still hot insert the cold dowel pin.
Let everything cool naturally (do not place in water)
I do have one question. How to you plan on creating the shaft bore size in the lever?
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Post by mhensen on Feb 4, 2016 18:06:12 GMT
I am not going through the axle.. I just made a dimple of a few mm.. Just to hold the axle in place..
I tried and made a 'test' version.. and thus far it seems to work.. Compression is working and the bolt hits the dimple nicely, so the axle is locked in....
A bit bulky.. but strong.. :-) and the rod end will be welded inside the smaller hole.. So there should be no play.. And if it doesn't work I'll have some extra work.. but I can keep the item intact, bore a bigger hole and need to weld in a Taper Bush
But that is just option 2.. For now option 1 seems to work!!!
I tried to find the power drive version but couldn't find any like it here!! |
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Post by mhensen on Feb 4, 2016 21:07:41 GMT
Actually, just thinking out loud so please correct me..
The levers are pretty nasty things to make if you don't have the right equipment or supplies..
Why are we actually bothering.. Why not weld it to the axle itself.. Worst case is that you want a new lever design.. Just cut of the axle, loose 50mm and turn the axle around and place the sensor on the cutted side..
Meaning that in my case I am considering just tacking the axle at 4 points to make sure it won't come off.. Why are we doing it all so difficult and spending time and money at various issues while it can be resolved so easy..
Please let me know what I am missing here.. Why not weld or tack the axle to the lever.. (tacking you should be able to grind it off somewhat)..
Although I do believe in my work in the previous message this might be just a safety think, just to be sure..
And new axles can be bought much cheaper that the custom made levers..
Again just thinking out loud and searching for the right answer.. In what case should we remove the lever? or do we want to remove.. :-)
Please help me?! :-)
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Post by GA-Dawg on Feb 5, 2016 17:12:37 GMT
Mhensen (Happy Friday to you)
Welding the lever to the shaft is certainly an option for some ( and one that I also considered) but there are a few points worth thinking about.
1. When you look at the platform there are a few places that are more likely to fail than others due to forces that are hard to calculate.
a. Bolt failure (used to secure the joints)
b. Hemi Joint failure
c. Lever failure
So making this items easy to replace was one of the key consideration for my design.
The other challenge I see is having the proper equipment. When I was creating this thread I was thinking it would be used for the novice fabricator/backyard mechanic. So I assumed they would be working in their own garage and only have access to the basic. Which is why I've been using my simple MIG welder, which I figured a DIY might have. I have also been using materials that are easy to source and work with which is why I am using 1x3 and not solid stock. So with my current design (I am going to rename that to option 1) you could use a simple welder to attach the lever to the shaft as the 1 x 3 would not require a significant about of heat to produce a weld with good penetration. But I also think this design is the one that is most likely to fail (lever might bends). Which means that you would have to replace the shafts with the lever (so more cost). Now If I switch to solid steel stock (like your using) I cant imagine what kind of forces would be required to cause the lever to fail/bend BUT to get it to properly adhere to the shaft you will need a professional grade welder and I not sure most would have access to that.
Given what little I have seen for the shop your using I think its safe to say that you do have access to a good welder (but I never like to assume) and welding the lever to the shaft makes perfect sense in your case.
A bit wordy, hopefully it makes sense.
-gadawg
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Post by mhensen on Feb 5, 2016 18:29:23 GMT
Hi Gadawg,
Thanks for you clear answer!! I liked how you relate all the 'issus' to your design and the public you intended you reach. I think you.ve accomplished that!
I do agree with the points you've made.. and you are right in my case with solid steel there is no way it could really fail..
And yes I do have access to a good welder..
The more I think about it, the more I am feeling for the 'weld it up' route.. AT least I would be sure there is no slippage possible..
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Post by GA-Dawg on Feb 12, 2016 21:10:16 GMT
Hi Mhensen, Your build is coming along nicely and I think welding it up was the best option given what you had access to. I have added gussets to my design, hopefully that will provide enough support. Time will tell. Oh and have you finished that beer yet (aviator) it's got to be warm by now.  -GA Dawg |
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Post by mhensen on Feb 13, 2016 15:54:09 GMT
Did the general layout today, so I'm n need of a new beer!!
the levers are quite bluky in comparison with yours and others but it will do the job :-) and that's what counts.. I hope yours are strong enough.!
Yep , lad I did weld it for sure..
I am quessing your aee mechanically also nearly ready ?!
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