Page 4 of 11 FirstFirst 123456789 ... LastLast
Results 46 to 60 of 164
  1. #46
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,763

    Default

    Thats great. What a bargain!

    Variety of make/models is good!

    Can't wait to see it apart.

    Simon

    Sent from a galaxy far far away
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  2. #47
    Join Date
    Aug 2010
    Location
    Near Bendigo, Victoria, AUS
    Age
    70
    Posts
    2,999

    Default

    My brand new $140 Makita turned up today. Have had a little play with it. It has variable speed from 0-2800spm but by trigger pressure. I'll see if I can fit a Bosch wheel speed controller I have here. Otherwise I'll use the speed control box I use with many of my other single speed tools - including the vacuum cleaner when I use it as a blower
    I may get a chance to open the gearbox later tonight or tomorrow. I'll take photos and may then make a suggestion of how a mod could work with this model.
    The weight seems about right.
    Cheers, Joe
    retired - less energy, more time to contemplate projects and more shed time....

  3. #48
    Join Date
    Aug 2010
    Location
    Near Bendigo, Victoria, AUS
    Age
    70
    Posts
    2,999

    Default

    Here we go....
    I've pulled the Makita apart to have a look what's possible and what's not.
    IMG_20220129_164638_262.jpg
    IMG_20220129_164648_380.jpg
    IMG_20220129_165213_631.jpg
    IMG_20220129_165542_659.jpg
    IMG_20220129_170040_872.jpg
    IMG_20220129_170117_829.jpg
    IMG_20220129_171617_358.jpg
    IMG_20220129_172101_137.jpg
    Findings: The crown gear does not have a counterweight. It is made from powder metal and is way too hard to machine.
    Secondly, the needle roller bearing it runs on takes up the full thickness of the gear.
    There is no space to add anything on top of the gear within the housing space as it stands.

    Suggestions: As 'Stustoys' did way back, one could add a layer in between the housing halves to gain enough height for an adjustable sliding mechanism for the eccentric pin, By fixing an additional disk onto the top of the crownwheel gear, eg with a dovetail or T-slot in it, which in turn holds the eccentric pin. I'll do some measuring and thinking....
    That would allow complete reversal of the internal modification.
    I haven't yet looked at the blade holding mechanism. Further thoughts coming soon.
    Cheers, Joe
    retired - less energy, more time to contemplate projects and more shed time....

  4. #49
    Join Date
    Aug 2010
    Location
    Near Bendigo, Victoria, AUS
    Age
    70
    Posts
    2,999

    Default

    Alright. I pulled the 'plunger' and it's bearing blocks out. The plunger rod is hardened and runs in two powder metal blocks (square section). The Scotch yoke appears to be welded onto the rod before grinding, and has a hardened steel slide to stop it tilting axially.
    So far, an oder of magnitude better than the Aldi machine, engineering wise.
    Once the blade holding mechanism was off, the end is just a 14mm dia. round rod with a slot in it. Would be very easy to make a scraper blade holder to fit over that and clamp on.
    I'm playing with CAD at the moment to come up with some preliminary drawings for an adjustable stroke mechanism.
    More later.
    Cheers, Joe
    Cheers, Joe
    retired - less energy, more time to contemplate projects and more shed time....

  5. #50
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,763

    Default

    Thanks Joe. I'll be interested to see what you come up with.

    Interestingly, the model I bought, JR3050T the parts diagram shows a slightly different shaped Scotch yoke.

    Simon

    Sent from a galaxy far far away
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  6. #51
    Join Date
    Jul 2006
    Location
    Athelstone, SA 5076
    Posts
    4,193

    Default

    there's a lot more grease in there than the XU1....lots more...maybe thats just one more reason why the XU1 aint going to go the distance over a Makita

  7. #52
    Join Date
    Aug 2010
    Location
    Near Bendigo, Victoria, AUS
    Age
    70
    Posts
    2,999

    Default

    Here are my (CAD) thoughts for the stroke adjustment mechanism to go on top of the crown wheel:
    Makita Saw Conversion v5 (Small).jpg Fixed block v2 (Small).png Slide v1 (Small).png
    I'm thinking I'll make a set in the next couple of weeks and see what works.
    I think the work flow would be: turn the round disk with the eccenter pin on the bottom to locate it (may need to try and drill another small hole for a second pinon the opposite side); cross-drill the disk from the solid end to the centre hole and tap it; then mill the dovetail slot; machine the dovetail slide and screwed-in adjuster in one piece for a tight fit. Cut off the slide part and screw in the short adjuster bit; then cross-drill through that and tap it in situ (maybe with the slide already in final position). The hole for the yoke bearing pin needs to be tight and accurately square, obviously.
    Grub screws from both sides will lock the slide in position. An alternative would be a longer slide with a one-sided adjustment screw with a captive cross pin in a groove - will give that a bit more thought....
    Making the housing spacer out of a sheet of 6mm aluminium should be straightforward.
    Cheers, Joe
    retired - less energy, more time to contemplate projects and more shed time....

  8. #53
    Join Date
    Apr 2019
    Location
    Adelaide
    Posts
    417

    Default

    Quote Originally Posted by Ropetangler View Post

    We may all be underestimating the quality of Ozito tools here. Way back around 1990 a builder I knew had lots of Ozito drills and saws, and he claimed to have built multiple homes and units with them with very few failures at that time. He told me that if one was to fail that he would send it back to Bunnings with his wife, if it was still in the warranty period, because he was well known to the staff there as a builder and Ozito were not marketed as professional tools. An added bonus was that they were much less attractive to thieves than high end brands like Makita or Festool, and no more likely to break when dropped or run over.
    If it lasted for 5 big jobs, I would hope that it would no longer be needed by me

    Anybody remember the GMC tools sold by Bunnings 20 years ago? Definitely suspect tools in terms of durability. Bunnings have since switched to the XU1 tools and now the Ozito. They would be very unlikely to put their reputation against tools that do not last. Built cheaper...yes. Not for heavy commercial use....yes. Light duty home use.....great bang for buck. Everybody has their own experiences with these tools and each is easier/harder on them than the next. I have an XU1 1/4 sheet sander that is still going after 20 years. I had an Ozito demo hammer that I killed on a 35+ degree day by working it wayyyy to hard and long. The replacement is going great.

    My Biax copy is based on the Ozito 850W router body. I have 100% faith in it lasting the distance as it is way over powered for scrapping so should just pur along at less than 50% load. Only issue is that I have had to design a multiple compound gear gearbox to achieve a 21:1 speed reduction.

  9. #54
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    55
    Posts
    2,120

    Default Biax/Bunax making group project

    Looks good Joe.
    The square internal corners in the dovetail might be a challenge
    I know that's not how you're intending it to be, but I started to think about how it could be done if actually needed.

    Milling the shoulders off the disc and bolting on solid blocks would do it - like this:




    Might even be an easier alternate way to do one (or both) ends instead of the small drilled and tapped dovetail piece you've drawn.
    Just musing...

    Steve

  10. #55
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    55
    Posts
    2,120

    Default Biax/Bunax making group project

    Opened up the used Bosch GSA900 I picked up yesterday.

    Very similar design to the Ozito that was posted earlier in the thread.







    Shaft is fixed in the crownwheel and rotates in 2 standard ball bearing races.

    The output rod from the yoke to the blade is a rectangular section with a twist just before the blade holder to change the orientation from horizontal to vertical.



    Edit: I did a quick file test and the back of the crownwheel appears soft enough to machine.

    Steve

  11. #56
    Join Date
    Aug 2010
    Location
    Near Bendigo, Victoria, AUS
    Age
    70
    Posts
    2,999

    Default

    @Steve: the square cornered/ended dovetail ist just my shortcut in CAD. I would have taken me another half hour to make it a semicircular end....the slider however can relatively easily be milled with a semicircular end to get full support and constraint at the shortest stroke end of travel.
    Bolting anything to the powder metal gear is the hard bit! I'm envisaging having to grind any holes with a diamond burr in a container of water....
    Even making a countersink on the existing hole for a screw - instead of the pin I drew on the round part would be a grinding operation.
    I might try making a hole in the gear in the next day or so and find out what will cut it....
    Cheers, Joe
    retired - less energy, more time to contemplate projects and more shed time....

  12. #57
    Join Date
    Aug 2010
    Location
    Near Bendigo, Victoria, AUS
    Age
    70
    Posts
    2,999

    Default

    @Mk1_oz: have you put some photos of your Ozito'ax on this forum? If so, link please. If not, please do.
    My Ozito multitool driven real Biax head lasted maybe 2 hours. I've got an old Metabo jig saw motor which is what Biax used in their previous model (before Metabo made it obsolete). I'll be making an adapter to drive it with that next.
    Cheers, Joe
    retired - less energy, more time to contemplate projects and more shed time....

  13. #58
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    55
    Posts
    2,120

    Default

    Joe - a solid rivet might be a good connection method between the crownwheel and the new part.
    Would only need a hole - nothing precisely sized etc.

    Steve

  14. #59
    Join Date
    Aug 2010
    Location
    Near Bendigo, Victoria, AUS
    Age
    70
    Posts
    2,999

    Default

    Just tried and succeeded in drilling 2 small hoes through the hard gear using a new tungsten carbide drill bit.
    So not quite as hard as I initially expected.
    Cheers, Joe
    retired - less energy, more time to contemplate projects and more shed time....

  15. #60
    Join Date
    Aug 2011
    Location
    Melbourne
    Posts
    4,763

    Default

    Very good. So do you think a HSS drill bit will go anywhere near it?

    Simon

    Sent from a galaxy far far away
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

Page 4 of 11 FirstFirst 123456789 ... LastLast

Similar Threads

  1. Biax anyone?
    By jhovel in forum METALWORK GENERAL
    Replies: 0
    Last Post: 29th Oct 2015, 04:37 PM
  2. Biax flaker anyone?
    By jhovel in forum EBAY, GUMTREE, and other off forum sales sites
    Replies: 0
    Last Post: 23rd Jun 2014, 01:58 AM
  3. What's a new Biax worth (to you)?
    By Michael G in forum METALWORK GENERAL
    Replies: 7
    Last Post: 11th Mar 2013, 12:28 PM
  4. Group or link all Group Buys into a sub-forum such as Member Deals
    By Bitslong in forum FORUMS INFO, HELP, DISCUSSION & FEEDBACK
    Replies: 1
    Last Post: 24th Jun 2009, 12:10 AM

Posting Permissions

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