584,325 active members*
6,106 visitors online*
Register for free
Login
IndustryArena Forum > Mechanical Engineering > Epoxy Granite > Epoxy-Granite machine bases (was Polymer concrete frame?)
Page 129 of 253 2979119127128129130131139179229
Results 2,561 to 2,580 of 5053
  1. #2561
    Join Date
    Jul 2003
    Posts
    586
    Those Italian Elte HF spindles are pretty tasty (and very affordable).

    whats affordable?

  2. #2562
    Join Date
    May 2003
    Posts
    792

    Thanks for the info Thomas. Much appreciated!

  3. #2563
    Join Date
    Apr 2004
    Posts
    41

    This thread

    The thread seemed to be stalling a little, so I am glad my posts fired it up
    again :-)


    This thread has had my attention more than anything I ever had
    interest in, I just wish the $$ was around last year for me to have some fun
    with it, Hope this year I can have some fun with my hobby.

    The spindle "affordable", somewhere in the range of 800 euro, so $1600 dollars??
    But they seem to only be collet chucks.

    Well still working on the house, just bought 888 sq feet of insulation for this
    weekends project.....it was degress here in Georgia this morning, friggin cold!!

  4. #2564
    Join Date
    Apr 2007
    Posts
    777

    Status

    speed33317,

    Thanks for giving the thread a good kick. It's freezing cold here in Alabama too.

    Lest anyone think this thread has run out of steam,
    Here's the work I know about:

    Jack is working on a front end for the aggregate packing simulator using the math model from the book by Francois de Larrard.

    I've promised to connect the front end Jack is building to the back end aggregate packing simulator I've written when he is done.

    Walter has built the parts for a CNC router and has passed from the E/G phase to the electronics phase. His work looked outstanding last time he posted although he hasn't posted any pictures lately. . .

    John has started his own thread about the spincast E/G machine he is working on.

    I've got a commercial building to work in , a large (48x36x36) Grieve 343 oven (needs hooking up), a new admet eXpert 5601 materials test machine, an old aremco vacuum chamber (needs gasket and TLC) and a leybold SV25 vacuum pump (which needs oil). Unfortunately, I'm doing bathroom renovation for my tenant instead of any E/G research right now. Once I get back on track, I should have some epoxy samples from reichhold coming. I may also have located a source of inexpensive aluminum oxide aggregate though the grading might be interesting.

    From Thomas's helpful post, we can see that a fairly wide range of aggregate designs will work and that vibratory compacting is important. Thomas's suggestion to google for silimix shows that the comapny that makes silimix is the european equivalent of agsco http://www.euroquarz.com/com/e_index.htm. It's certainly possible to build a machine with the info we have now on this thread.

    Some folks like Jack and me are interested in optimizing the formula and creating a formula that is provably the optimal one.

    Thomas's suggestion to use an aggregate mixture based on fuller's formula is reasonable but it must be kept in mind that according to de larrard's book of the 7 common and or reasonable aggregate designs, Fuller's is the worst performing in terms of solids density. According to the rule of mixtures formula posted a long time ago, such a formula will be less rigid than it could be. Also, the greater the epoxy content, the worse the creep problem. [Creep won't matter to wood router guys much but to folks building precision metal working gear, it's problematic.]

    If anyone is interested in applying the knowledge we have now to build something, feel free to post and we can gather up what you want to know and post.

    If anyone is interested in helping to research the optimal formula, please don't hesitate to post here either. There's lots of research to do as well as software to write.

    to peach mcclure:

    80/20 is a type of aluminum channel that is used for making various mechanical things. It's somewhat expensive but there are all sorts of fittings for joining pieces of it etc. The test machine I talked about above has the load frame made from 80/20 channel.

    In short, I think Thomas, you are way ahead of us on building actual machines however I think that some of what we've found out about aggregate designs is useful although the time to use this info will be later.

    Regards all and Thanks to Thomas for Posting!

    --Cameron

  5. #2565
    Join Date
    Dec 2004
    Posts
    1137
    Quote Originally Posted by ckelloug View Post
    speed33317,

    Thanks for giving the thread a good kick. It's freezing cold here in Alabama too.

    Lest anyone think this thread has run out of steam,
    Here's the work I know about:

    Jack is working on a front end for the aggregate packing simulator using the math model from the book by Francois de Larrard.

    I've promised to connect the front end Jack is building to the back end aggregate packing simulator I've written when he is done.

    --Cameron
    Ah, now this is something I can contribute too. My current specialty (and a previous hobby) is coding PHP front ends to spreadsheet type calculations. I wrote an electric brushless motor calculator and database for a start up called www.gobrushless.com. The user was able to design and simulate winding their own motor and picking their own battery source, current limit, and propeller dimensions. It worked great but the site owner labeled it under construction because the GUI didn't match the site redesign. Long story short, I could help by providing a web version of the simulator with the possibility of a graphical representation of the "packing" based on behind the scenes calculations.

    I'd do it just for the fun of it, I'm not planning on building an epoxy machine

    edit: here is a link to the thrust calculator. It use exponential regression to calculate the thrust of a propeller at 600 above sea level based on experimental measurements. http://www.gobrushless.com/testing/t...=Calculate+Now

    Jay

  6. #2566
    Join Date
    Mar 2004
    Posts
    1306
    Servus Thomas,

    Danke fürs kommen.

    I think it was a shame that the thread on the German forum was stopped. It was a very interesting discussion, and I am sure the lessons learned as you move from your prototype to the first commercial design would be very interesting.
    Regards,
    Mark

  7. #2567
    Join Date
    Nov 2007
    Posts
    78
    Hello Mark!

    Danke - immer wieder gerne!

    You're right - we got much knowledge during the development time and paid training money. All this I never published more in a forum for the reasons designated by you.
    There are some tips 'n tricks we found in the development phase we improved the production steps too.

    In the start time we poured a great many material cubes to test. Some of it we could not destroy no more also by raw force. ;-)

    I will try in the next days a few principles for the mineral casting to write´here. Forms, pouring, separation castings, gate parts and so on.

    Bye
    Thomas
    from Germany Bavaria

  8. #2568
    Join Date
    Jul 2003
    Posts
    586
    is there a us distributor for silimix?

  9. #2569
    Join Date
    Nov 2007
    Posts
    78
    Hello the4thseal!

    I don't think so you can purchase silimix in us. Cameron wrote about "agsco". Perhaps
    this is an equivalent in us to silmix?

    Bye
    Thomas

  10. #2570
    Join Date
    Dec 2006
    Posts
    325
    Cameron,
    Isn't it surprising that the people at Euroquartz use Fuller's parabola to make their mixtures.

    best regards

    Bruno

  11. #2571
    Join Date
    Apr 2007
    Posts
    777
    Bruno,

    The difference Between Fuller's parabola and the very densest packing is about 7%. A mixture made on Fuller's Parabola will be much much better than a haphazard mixture of rocks and nearly as good as any of the other mixtures unless great pains are gone to. Fuller's formula is very popular, especially in the U.S. while some of the slightly better formulas for concrete aggregate are more popular in Europe.

    If the rule of mixtures calculation is to be believed, that last 7% will make a measurable difference in the modulus of the mixture. I also suspect that minimal epoxy will also minimize deformation due to creep which we haven't really begun to address.

    For making a general purpose CNC machine, Fuller's formula is just fine. You were good to have come up with it so long ago on this thread. I'm working on optimization which may not even be in use by the pros yet. The minimum segregation mixture from de Larrard upon which I base my formulation advice will be both denser and have less tendency to separate under vibration than Fuller's mixture.

    In that carefully graded mixtures appear necessary both from our and Thomas's research, I'd rather pay to have somebody like agsco grade a mixture to the nearly optimal minimum segregation curve (0.3% from optimal density) than to Fuller's formula if I'm going to pay to get graded aggregate.

    With regards to 4thseal's question, if you ask agsco to make a mixture of quartz graded to a Fuller curve, you'll get approximately what Thomas says he is using.

    Regards all,

    Cameron

  12. #2572
    Join Date
    Apr 2004
    Posts
    41

    This thread

    The science part I will leave up to the smart guys :-)

    You tell me , Put this many rocks in this bowl, this much epoxy in this bowl, then put
    them in this bowl and mix em up , then put it in that box and shake the crap out of it.

    That's what I will do :-)

    Building stuff, mechanic repair, electrical diag and wiring Ok with me, math no way....

    Oh and I got 70% of my insulation in tonight after work and it is 27 degrees out and the house is actually warming up for a change.....I am dreading my gas bill for the past month
    the heat was running non stop.......

  13. #2573
    Join Date
    Jun 2005
    Posts
    334
    Found this today; http://www.resins.com/resins/eu/pdf/...al_Casting.pdf

    "Epikote™ Resin 05102 in combination
    with Epikure™ Curing Agent 04998 and
    precisely graded mineral fillers is a
    system recommended to cast machine
    bases or structural components such as
    sanitary equipments, scale bases, tiles
    and other elements."

    There formulations seem counter intuitive.

    Jack

  14. #2574
    Join Date
    Apr 2007
    Posts
    777
    Jack,

    What seems counterintuitive? What they suggest looks quite reasonable in terms of aggregate. Their curves bend the right direction. I've recently learned that the all parts equal formula that I've posted here in the past was an over-simplification of the actual optimum formulas and I'm working on correcting it.

    As for resins, the reactive dilutants are also used in the reichhold stuff we've been examining although we would have to add more diglicidyl ether to make the viscosity that low.

    In general, this data sheet clears up any confusion on whether we were on the right track and it means that a machine can be built with off the shelf technologies that are well characterized!

    Kudos to Jack for finding this supremely important and interesting document!!!!

    Regards all,

    Cameron

  15. #2575
    Join Date
    Jun 2005
    Posts
    334
    Quote Originally Posted by ckelloug View Post
    Jack,

    What seems counterintuitive?
    DOH!! Drainbramge... I thought the graphs were in Volume, not MASS.

  16. #2576
    Join Date
    Dec 2006
    Posts
    325
    Gret Info Jack!

    Best regards
    Bruno

  17. #2577
    Join Date
    Jun 2005
    Posts
    1425
    Getting near to mixing up some e/g, I thought I'd better revise the recipe, and how I could best use the material I have available.
    This led me to thinking that if one were to start with a known range of materials, perhaps not ideal, then by modifying the proportions of the different components one could approach an ideal mix. This sounds like some fairly heavyweight maths is needed
    However, I started searching for references to the Fuller curve mixture, as I wasn't to clear on that, and I tripped over this site http://people.fsv.cvut.cz/~svobodal/aggmix/

    While I can see that it is exactly what I was looking for, two problems - 1. Neither I nor Google translator speak Czech, and 2. the download of the software is no longer available.

    So I post it in the hope that it may be useful if anyone can get a handle on it.

    John
    It's like doing jigsaw puzzles in the dark.
    Enjoy today's problems, for tomorrow's may be worse.

  18. #2578
    Join Date
    Jun 2005
    Posts
    1425
    On second thoughts, I can see that I'm going round in circles again.
    This is the thought train that led me to try building the particle separator, and best quietly forgotten.
    Perhaps a better approach would be a method of dry mixing the aggregate that gave you some indication that the proportions were getting closer to "ideal " as you added each new size in turn. I remember Walter writing that the dry mix became very difficult to stir after adding some of the fine particles. Could this be quantified ?
    Is it a noticable effect earlier in the mixing with the larger components ?
    John
    It's like doing jigsaw puzzles in the dark.
    Enjoy today's problems, for tomorrow's may be worse.

  19. #2579
    Join Date
    Apr 2007
    Posts
    777
    John,

    The simplest solution (and superior to Fuller's ratio) Is to use equal parts of what you've got. If you know what you've got then we can feed that info into the Compressible Packing Model stuff I wrote from de Larrard's book eventually using the GUI Jack is working on to get an idea of how to adjust the mixture.

    The curves in the Hexion Doc that Jack just posted are very close to the optimal curves so we really don't need to do a lot more research on the "right" aggregate mixture.

    There isn't a need to complicate this any more than we already do. With the hexion grading curves, if you have graded aggregate, you can just follow the recipe. Likewise, if you have a wide variety of aggregate sizes you can just throw in equal parts of what you've got subtracting about 10 percent from the median size particles.

    I'm going to finish the modeling software with Jack so we can predict exact properties of a variety of mixes but with those curves from Hexion, anybody who is waiting for a substantially better aggregate formulation to build a machine isn't likely to see more than a few percent better. These Hexion curves are superior to Fuller's ratio and one could even order the epoxy from Hexion.

    There is no need to replow the ground covered in the last 2500 posts unless you want to work towards a better computer model. Given the Hexion curves, and the equal parts theory, just build it.

    Regards all,

    Cameron

  20. #2580
    Join Date
    May 2003
    Posts
    792
    Quote Originally Posted by ckelloug View Post
    In general, this data sheet clears up any confusion on whether we were on the right track and it means that a machine can be built with off the shelf technologies that are well characterized!

    Kudos to Jack for finding this supremely important and interesting document!!!!
    I guess the big question is - do we follow them, or are they following us?
    This stuff sounds very familiar..

Page 129 of 253 2979119127128129130131139179229

Similar Threads

  1. Replies: 71
    Last Post: 08-25-2020, 01:18 PM
  2. Replies: 14
    Last Post: 11-13-2015, 02:57 AM
  3. Replies: 9
    Last Post: 01-15-2014, 11:39 AM
  4. Index to "Epoxy-Granite machine bases" thread
    By walter in forum Epoxy Granite
    Replies: 13
    Last Post: 12-02-2011, 05:45 AM
  5. Epoxy-Rice Machine Bases (was Polymer rice frame?)
    By mdierolf in forum Mechanical Calculations/Engineering Design
    Replies: 18
    Last Post: 11-02-2008, 04:16 AM

Tags for this Thread

Posting Permissions

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