Results 1 to 7 of 7

Thread: Redrive Built In House..

  1. #1
    Member Bart's Avatar
    Join Date
    Dec 2015
    Location
    Valdez, Alaska
    Posts
    487

    Redrive Built In House..

    Well, a couple of weeks ago I went to post some updates on my redrive build, and I found out that it had to be removed do to problems that the site had. Do to the resent hacks.
    It was kind of fun to think about the progress that I had made. from not owning a lathe, and dreaming about making one vrs. purchasing one.
    the truth be told. with the time involved and parts and pieces, it would be money in the bank to have purchased one..
    but I have learned a lot, and it has been a fun and learning project.
    2 years ago if anyone had asked me to take a 2" threaded stud bolt and make a shaft for my driven pulley, I would have said good luck. but I did that yesterday.. I have came a long way..still have a ways to go.
    the design has been upgraded, changed and revised more than a few times.
    and by the time it is over, I should have 2 different styles
    1 with a brace only on the drive pulley, and the other with a full front plate.

    so forgive me if I am jumping into the middle or tail end of this project. I may go back and fill in some of the blanks, but I didn't do to well at organizing the pictures at home with 2 different computers and picts, scattered all over the place...

    So I had made a driven shaft, bearing holders for both the upper & lower front plate, but have been waiting on a friend with a mill to drill out the holes in the front plate. might happen yet...
    but the driven shaft had a slight problem, that taper was 0004 out. not good, i have been thinking about what went wrong with that for the last couple of months.
    finally I may have figured it out. I did not have my taper attachment plumb with the lathe bed. maybe in a few I will attempt it again.
    in the mean time this last week, I turned out 4 shafts, with 2 different styles. it has been an learning and growing experience. threading can be so simple. but one careless moment. what should be the end, turns out to be the beginning of the next one...
    the final one out of the stud bolt was some hard material. went through a few carbide inserts. and was doing the final threads 1-1/4 by 12 tpi. and the nut would start. so i ran a file over the top of the crown, then went to do a clean up pass with the lathe, and some how I had bumped something, and it was a 1/2 thread off....
    so now the final product has a groove that a set screw will set in to lock it in place. no need for a lock nut.
    I had the other style that was made out of a 1-1/4 shaft with a spacer to hold the pulley off of the back plate. and had put 1-14 threads on it. I really didn't like reducing the shaft for that thread size. so I found a 1-1/4-12 nut. and I am liking how it looks.
    ps. I pick up an old band saw. replaced some parts. and it cuts real nice.
    Attached Images Attached Images       

  2. #2
    Member Bart's Avatar
    Join Date
    Dec 2015
    Location
    Valdez, Alaska
    Posts
    487

    Re: Redrive Built In House..

    one of the things that I had been contemplating was what type of pulley tension style to use. after thinking about this for the last couple of years. I ended up turning out a 94mm / 3.75 x 2" deep, custom pulley, I will be using a bar that pivots to hold it to the back plate. It is a simple design, I kind of borrowed it from the link below
    https://www.dedicatedmotorsports.com...p/551617-1.htm

    It is looking nice, but I might change, and use a concentric lob on a shaft, I turned one out of a 1.5" blank, but was only getting about 3/8" of movement. might have to use a 2" dia. blank and see what that looks like
    I will be using 2 bearings to keep things in line.
    Attached Images Attached Images     

  3. #3
    Member Bart's Avatar
    Join Date
    Dec 2015
    Location
    Valdez, Alaska
    Posts
    487

    Re: Redrive Built In House..

    the next item on the list is to fab up a prop hub extension. where I will be mounting a bearing on the outside of the drive pulley. I need to extend the prop a little to clear it.
    as you can see from one of the photos, where I have the bearing plates attached to the pulleys. I do need to extend the prop out, for clearance. the distance between the back plate and the bearing plate is 4 inches.
    the designs are rather simple,
    1 keep things concentric
    2 4 inches in dia.
    3 line up the bolt pattern. these will be 6 holes on a rotax 75 mm circle, 21/64 dia.
    4 keep everything concentric.
    5 mounting extrusions on both ends to mate up to the driven pulley, & center the prop on

    one of the things that I am looking at. is the different diameters that different prop makers have on their props
    the hub I purchased from Arrow Prop. a few years back, has a 1.5 dia. plug. this matches a few of the wooden props I have seen
    I had milled out my warp drive plate to match that.
    But my ultra prop has a 1" centering plug.
    with these 2 sizes. I am thinking about making an removable insert to accommodate these 2 sizes.
    with the rotation I should be okay using a right handed bolt to hold the insert in place..
    "my cuyuna motor has the other rotation, and it uses a LEFT handed 1/2 -20 bolt to hold the hub adapter to the shaft."

    It is kind of fun to see some of these things coming together. I wish my drafting friend was around to draw this up. but I have learned a few things, one is to put some measurements down on paper before starting any cuts, and think about it for a day or two.

    I still do not know which prop I will be using, I may be using the warp drive 3 bladed prop. where I can adjust the pitch.
    allegedly with the fuel injection update on the motor, I have read that I should expect about 20% more thrust.
    where the ultra prop, I will need to figure out the pitch blocks, all this to keep the rpm in check
    both of these props are still at 60 in. diameter.
    I just don't know what all to expect...
    Attached Images Attached Images    
    Last edited by Bart; 12-01-2019 at 05:26 AM.

  4. #4
    Member Bart's Avatar
    Join Date
    Dec 2015
    Location
    Valdez, Alaska
    Posts
    487

    Re: Redrive Built In House..

    so I spent a little time on the hub extension today, and it is starting to take shape, it seems that I will think about what and how I want it to look for a good while, then spend a few days to turn the project out. the biggest part of any project on the lathe, is to think through all the steps, that can be accomplished with out removing the piece. Like with this hub extension.
    I centered the piece in the lathe, then faced off the front and the side up until I got close to the jaws. Then with the cap that came with the pulley, I drilled a hole to center it to the piece, where I would use it as an template to drill the 6 mounting holes. knowing how easy it is for the template to rotate while drilling all the holes. I drilled and tapped the first hole, put a 1/4-20 bolt in it. then went to the opposite side, & drilled and taped that hole also. then I felt confident in drilling the 4 remaining holes. I used a ss sleeve to center the drill bit, so the hole would be centered to the template hole, and also I didn't want to elongate my pulley cap. "don't know if and when I may need it again."
    then it was off to the races. or removing the aluminum in the center, that took a little time. where after each pass I was cleaning up the chips. more than once they got rapped around the work piece, the tape helped a good bit to keep things from snagging on the chuck jaws.
    from just the little that was removed, I was able to fill a bag full of tinsel. I think that took the most time was stopping the lathe and cleaning things up after every pass, if not it always gets exciting when a birds nest wraps around the work.

    The Pulley came with 1/4-20 threaded holes. It had a warp drive 60" dia. prop mounted to it. and was originally on used on a Hirth 50hp motor.
    looking at many of the Rotax hub extensions, they are all using an 8mm bolt. Which is just .2638" I am contemplating replacing the 1/4" bolts with 5/16 bolts which would be .3125.
    I will be using 5/16 bolts to mount the prop to the hub. a question I have, about the prop side of the hub, I never see any of these holes threaded. would that be due to manufacturing, it would take just a little longer?
    At the moment, I am in the mood to thread those holes, still put a lock nut on the bolt. I may need to put some anti-seez on the threads so they don't gall after some time.

    All that is left is to turn the hub around, drill and tap 5/16's threaded holes. & make a coupled of plugs for centering the different props.
    my thoughts are to use some 1.5 round stock, and use a 5/16th right hand threaded socket head cap screw to hold them in place. and have the base recessed about .25 into the center of the hub.

    p.s. if anyone needs a bag a ready made tinsel for the holidays, let me know. my wife is refusing to let me decorate the tree with it..I had to throw 3 bags away today. there was some nice colors. blue, bronze, silver, burnt. " color & thickness is dependent on the speed and how big of cut I take."
    Attached Images Attached Images        
    Last edited by Bart; 12-02-2019 at 10:14 AM.

  5. #5
    Member Bart's Avatar
    Join Date
    Dec 2015
    Location
    Valdez, Alaska
    Posts
    487

    Re: Redrive Built In House..

    well turning out a hub has been an learning experience, in hind site I should have ordered 2 blanks, the method that I used to drill the bolt holes, the first 12 holes turned out great, then I thought of putting another set of holes, ended up breaking off a tap. needless to say I don't know if I would have ever made it as a dentist.

    but I will see about filling in the cavity with a little weld material, and I might be able to salvage it.
    For some reason I made this a 4 in. extension, it gives me a little play room with the 2 props. the warp drive I have 2.25 clearance, and the ultraprop, I have almost 3 inches clearance, I really don't know how close I the prop next to the lower hub bearing... any ideas???
    took a little time to get things lined up better, between the upper an lower pulleys, there is only a .003" difference between them.
    there has been a few other things that I may end up changing. looking at the bolt landing next to the prop. I had left it at 1 inch thick, but now looking at the arrow prop hub, and the hubs from my cuyuna, they are 1/2" & 5/8" thick. The bolts work with a thinner landing, where a 1" landing doesn't work so well. at the moment i have turned it down to a .700" and after filling in the cavity thinking of leaving it 5/8" thick.
    Attached Images Attached Images      

  6. #6
    Member Bart's Avatar
    Join Date
    Dec 2015
    Location
    Valdez, Alaska
    Posts
    487

    Re: Redrive Built In House..

    I also ended up taking most of the radius out of the inside of the extension, so I could get the bolt to set square to the extension. a lot of the pictures that I have seen on the extensions always had a inside radius, but with using a 75mm radius. it just was not happening,
    here are also a few picts. with my hub extension, and the 2 other hubs that i have showing the thickness.
    a lot of it is I am having fun just trying to see if I can actually make this happen, and I have a better idea now, on what to look out for on the next hub extension, but this will work for fit up and going forward..
    Attached Images Attached Images    

  7. #7
    Member Bart's Avatar
    Join Date
    Dec 2015
    Location
    Valdez, Alaska
    Posts
    487

    Re: Redrive Built In House..

    took a little time and filled in the holes, went a lot simpler than I expected, with the mig gun, tig would have been a lot simpler & cleaner. But it cleaned up nice and there was no cavities, when I took another .100 off.
    the landing on the prop side is .63 wide, & the pulley side is just under an inch. With a total length of just over 3.5 inches.
    when the other blank comes in, it should go a lot easier, now that I have a little better idea on process of steps, and have a finished product.
    I will be making a small tool to help keep the tap straight, so I don't have the problem of breaking one off again.
    Attached Images Attached Images   

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •