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  1. #1
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    Default Very ott welded saw back for a back saw.

    Very OTT welded saw back for a back saw.

    Now ,say that fast, after a couple of dirty grannies(there a cider ,get your mind out of the gutter)
    Non welders will possibly start dropping off from this thread about now.
    Spending considerable time away from ones creative zone(that's fancy for shed) gives one ,one the ability to come up with the most inmagntive ideas.
    My latest hair brain Idea, is yes welding some steel pieces together to form a steel back for a back saw.
    Now among the saw purists ,it seems the norm is for shinny brass,either traditional folded or slotted.
    For me ,this posses a slight problem,
    I like a bit of bling in my tools ,but not of the gold brassy look.
    More along the lines of shiny silver polished steel look.
    Sterling silver is out of the my price range at present,tho ,I have asked the better half to look into that[emoji849].
    So my rumbling thoughts so far .
    Two identical pieces of steel ,ruffly 200/300 mm long ,say 15/20 mm deep and about 2/3 mm thick.
    I haven't actively gone looking for steel stock yet ,but will obviously use what is readily available stock.
    So ,don't take these measurements as gospel.
    The two pieces will receive the exact same treatment ,so I will just talk about one for now.
    The steel on one face is smoothed off ,either using some wet and dry attached to float glass or in my case my small surface plate.
    Taken to I think ,240 grit would be more than enough possibly even 180 would be fine.
    Some might even stop at 120.
    The purpose of this if you haven't clued up on my grand scheme.
    Is to face the saw plate tightly.(struggling here with the right big words lol).
    Or this could also be done with steel held down on a know flat surface and smoothed with a diamond or water stone.
    Or even draw filed with marking blue!
    Being careful of course to flatten the steel and not make it convex.
    The goal is really just to give us two flat faces on the steel.
    Unless you want to use some of the exotic stuff A2 O1 for instance which generally comes very nicely smooth all ready.(Of which tho I have definitely considered)
    My choice of plain Jane mild steel is I'm quite comfortable welding mild steel in the said thickness.
    I've never welded the other stuff or even know if it can be welded?.
    Once this is done the edge of the steel on one edge will be slightly beveled maybe four five degrees at the max.
    This is to enable a good penetration of the weld to come.
    Now ,once this is all done ,to now both pieces of stock.
    The two pieces are placed together spaced out with the required saw plate.
    Noting the saw plate to be position suitable far enough away from the weld fillet ,but not far enough away letting the two halfs of the saw titl back to come together.
    I'm working on the theory here that saw plate say for argument sack is .6mm(0.025")
    That's not to bad a gap to weld up, some would say even advantages.
    Now before those start yelling at me ,that this will warp and bend all over the place the two backs of the saw back plus the spacer plate(saw plate)
    Are all sandwiched between to big heavy pieces of angle iron,say approximately 50 mm deep 3/4 mm wall thickness and placed in my old machinest vice and clamped down hard.
    To one,stop the whole sandwich becoming a donut by acting as a heat sink.
    Plus a few G clamps at each end that hang out of the sides of vice.
    As I think the vice jaws from memory are only about 150 mm long.
    Then for the main event weld the plates up to become one whole glories steel saw back.
    This might actually take two complete passes.
    But the bonus off this is because I intend to do this in winter I may enjoy some warmth for about ten min fantastic.
    Of course once the weld has cooled it will need dressing up with some filing.
    I'm thinking of oxy welding this as the weld is generally easier to file or grind then a mig weld.

    A short re cap, grab some steel sandwich a piece of saw plate between them weld it up nice and tight!!!
    Then grind file it smooth.
    So to all the budding saw builders,have I just come up with the most fantastic idea ever to grace these pages? or massively over thought the idea?
    All comments and encouragement taken on board.
    Including the well try and tell us how it turns out.

    Note point this is all theory though up while I should possibly be doing other more productive life matters[emoji849].

    Cheers Matt
    Apologies if you have read this and now feel sick[emoji41].

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  3. #2
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    Quote Originally Posted by Simplicity View Post
    A short re cap, grab some steel sandwich a piece of saw plate between them weld it up nice and tight!!!
    Then grind file it smooth.
    So to all the budding saw builders,have I just come up with the most fantastic idea ever to grace these pages? or massively over thought the idea?
    All comments and encouragement taken on board.
    Including the well try and tell us how it turns out.
    the back will warp and you'll never get the saw plate straight


    what I've learnt from welders is when doing similar, the first pass is a series of tack welds, the second pass is the full length / depth

    "thoughts"
    weld overrun inside the formed slot will weld the blade blank or spacer in place
    might be achievable using a series of wedges to keep the open side "open" -- but it'll still warp enough to be useless as a back

    how hard is it to machine mild steel with a carbide slot cutter and cutting fluid?
    regards from Alberta, Canada

    ian

  4. #3
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    Quote Originally Posted by ian View Post
    the back will warp and you'll never get the saw plate straight


    what I've learnt from welders is when doing similar, the first pass is a series of tack welds, the second pass is the full length / depth

    "thoughts"
    weld overrun inside the formed slot will weld the blade blank or spacer in place
    might be achievable using a series of wedges to keep the open side "open" -- but it'll still warp enough to be useless as a back

    how hard is it to machine mild steel with a carbide slot cutter and cutting fluid?
    Ian,
    I’m sorry I disagree.
    The parts will be sandwiched between two heavy and thick walled L sections as I made mention too in my thread.
    Then clamped in a vice(call it a welding jig)
    I do agree a few tacs to start with can not hurt followed by a single pass.
    But if they buckled yes you could still get the saw plate straight it’s just a matter of time.
    Granted the time may not be worth the effort
    But can always be done.

    I also disagree that weld overflow will weld the space block(saw plate in place).
    I intended for the saw plate to be approximately 3/4 mm below the weld fillet.
    If you were welding in such a away that the weld is dropping from the weld puddle to the floor of the weld and onto the spacer block(saw plate)
    You need to adjust your welding style.

    It’s not hard to machine mild steel if you have the right equipment I don’t.[emoji849]

    Cheers Matt

  5. #4
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    coming back to this.

    I don't think I've ever seen a weld like you are describing. But it might be common in spot welded car bodies.

    assuming that your back pieces are 2.4 mm thick (= 3/32"), I think that the bevel (on both pieces) along the join line should closer to 45 degrees than 4 or 5 degrees. As I envision the bevel you would be aiming for a weld fillet that was around 4 mm wide (including the gap for the saw plate) and 2 mm deep. Though I'm not sure that 2 mm deep is deep enough, perhaps given the likely post welding cleanup, the fillet depth needs to be closer to 3mm.

    What I think might happen is that while the steel is held in the clamp, the weld will cool and contract resulting in the saw back springing open when released from the vise.

    Silver solder might be a better option than oxy or MIG welding. And closer to your preferred level of bling.


    I remain concerned that your heat sink may actually worsen any warping.
    I'm thinking that after tacking, the full weld should be built up in short strips separated by long gaps.
    (dividing the length to be welded into 20 sections, the weld pattern might be [strip numbers] 3, 7, 11, 15, 19, then 2, 6, 10, 14, 18, then 4, 8, 12, 16; then 5, 1, 9, 13, 20, 17. For a 300mm long back, each strip would be 15 mm long.)
    regards from Alberta, Canada

    ian

  6. #5
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    Matt, I think it will pull towards the weld even if you clamp/jig it. We used to balance weld to prevent that happening but you can't do that. Are you going to use MIG? That will reduce the pulling but TIG or oxy I would not recommend at all. The problem is the depth of material under the weld, there is not enough to prevent the tendency to prevent pulling into the weld. I suppose it is like shrinking a panel, that will be what happens to the material being welded. We used to pull pressed in cylinder sleeves out of engine blocks using the same technique, run a stick welder down the inside of the sleeve and it would shrink and fall out.
    CHRIS

  7. #6
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    Ian,
    Thanks for the comments and thanks Chris too.
    Ian, I think what I meant about the weld puddle was that if the puddle is falling through then you need to adjust your weld.
    But, I am taking on what your both saying that even with the back being in a jig.
    The weld may and I’m saying may cause the back to distort some.
    My choice in choosing oxy was one I like oxy welding but Ye not really the best reason.
    Also i was let to believe that an oxy weld is softer than a mig weld and easier to manipulate.
    Unfortunatelyi don’t have a tig or know how to tig weld.
    But I think maybe I should just do it and prove you both right.

    Cheers Matt

  8. #7
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    Quote Originally Posted by Simplicity View Post
    I think maybe I should just do it and prove you both right.
    or wrong
    regards from Alberta, Canada

    ian

  9. #8
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    All TIG is electric oxy welding and if you can oxy weld then you can TIG weld. Out of position stuff like small pipe can be a bit tricky as I found when doing my pressure ticket but it is not that difficult. Give it a go but I think it will bend along the length of the spine TBH but you'll never know if you don't have a go. MIG was invented so untrained monkeys could weld furniture together!
    CHRIS

  10. #9
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    Matt

    I think you should give it a try even if it is to prove it is not viable.

    I would look at least a double thickness of saw plate to space the two halves. My reason: The weld along the top of the spine will contract as it cools and tend to "splay" the lower edge which grips the plate. The larger space will give more movement to press it closed and replicate a folded back. (A typical folded back would have a gap at the top and be touching at the open edge.) Your main issue then is to keep the spine straight which I think you could do with heavy section angle. I am assuming that you will not have the actual saw plate in the spine when welding. That definitely would not work. If nothing else you would take the hardness out of the plate with the heat from welding.

    I would be tempted to use a Mig welder as it does not impart so much heat as a stick welder and is better at filling a gap. Tig would be good but you need to have a Tig welder for that!

    Regards
    Paul
    Bushmiller;

    "Power tends to corrupt. Absolute power corrupts, absolutely!"

  11. #10
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    Wouldn't it be easier to just make a folded back?
    I thought that your panel work history would make that an easier path.
    The TGIAG team used to offer both steel and brass folded backs but I see they now only offer brass.
    Now: http://tgiag.com/sawbacks.html
    Then: https://web.archive.org/web/20150502.../sawbacks.html
    I'm sure one of those steel backs would polish nicely.
    Alternatively, buy a $15 backsaw from Bunnings, take the back off it and polish it up.
    Quicker and cheaper than a pack of welding rods.

  12. #11
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    Gavin

    Fair comments, but folding a back without specialised machinery is not easy as I found out to my cost. Matt is much more accomplished than me however. The problem with "pinching" a back from a Bunnies cheapie is that they are so light and flimsy. Only really suitable for something like a gents saw.

    The two guys in a garage make a good product and they would polish well (the backs, not the guys). Trouble is they would be $70 to $90 depending on size, landed in Oz after shipping and converted to upside down dollars.

    Regards
    Paul
    Bushmiller;

    "Power tends to corrupt. Absolute power corrupts, absolutely!"

  13. #12
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    Quote Originally Posted by Bushmiller View Post
    Gavin

    Fair comments, but folding a back without specialised machinery is not easy as I found out to my cost. Matt is much more accomplished than me however. The problem with "pinching" a back from a Bunnies cheapie is that they are so light and flimsy. Only really suitable for something like a gents saw.

    The two guys in a garage make a good product and they would polish well (the backs, not the guys). Trouble is they would be $70 to $90 depending on size, landed in Oz after shipping and converted to upside down dollars.

    Regards
    Paul


    Paul,
    I was wondering what you were doing???

    Some good points have been brought up and I’m now in second question stage.That will be shortly followed by intercourse ,it I just bloody do it and not think too much lol.
    One point I’m planning on gas welding it together ,because as I’ve previously said ,I’m best at gas(oxy welding if your native bogun Ozzie)
    I don’t have a stick welder and never will, I hate them.,violent little noise smelly welding things.
    Followed shortly by MIG welding ,which I do have .
    But gas welding is much more romantic.
    Also ,have gas welding gives me the chance to use a bit of heat if needed and not just for some shed warmth in the middle of winter.[emoji849]
    I may one day get a tig welder tho, but that is way in the future.
    Given you asked why I don’t just fold one being an ex beater,and that’s a good question ,I have folded a back in a previous saw making attempt.
    I still have and plan on using that back one day!!.
    I’m just having a little time off ,from that saw as we both have issues to sort out lol.

    Folding 1mm steel is fairly easy ,folding 2/3 mm steel is a whole lot harder physically and technically.

    Just had a look at the “two guys in a garage”stuff .
    Wow ,fantastic stuff ,but it states they don’t post out of the states.

    There folded backs look great ,but I’m aiming for a more modern look and I personally prefer the shape of the milled brass backs but in steel as I love the look of polished steel more than traditional brass.
    As Paul stated, I don’t think buying a Bunnings saw for parts is really going to cut the mustard.
    But ,as I just mentioned and in previous posts, I think this is going to have to be a suck it and see idea.
    Im personally hoping it works[emoji849]

    Cheers Matt

  14. #13
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    What about going to a market and buying an old saw and using the back off that.
    I am learning, slowley.

  15. #14
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    Default Very ott welded saw back for a back saw.

    Quote Originally Posted by Pagie View Post
    What about going to a market and buying an old saw and using the back off that.
    We’re would the pain be in doing that !!
    The older saws mostly have folded steel backs which have a curvature to the top of the back due to the nature of bending the steel.
    The outside must stretch the inside must shrink
    I’m wanting a more squared back look.
    Does that make sense?

    Cheers Matt

  16. #15
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    Well Matt, if you want pain, then I suggest a nickel plated brass spine.

    Saw parts from Blackburn Tools are now carried locally by The Wood Works.
    Hand Saw Making & Repair

    So get yourself a nice spine and some split nuts:
    Hand Saw - Maintenence & Care : Spine, Stiffener, for 12 inch (305mm) CARCASE SAW, BRASS
    http://www.thewoodworks.com.au/shop/...per-set-detail

    And you can pickup a non-toxic nickel plating kit from Caswell.
    EN1 Electroless Nickel Kit 2.4 Litres | Caswell Australia

    Should look a treat!

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