Jump to content

Namerow

Members
  • Content Count

    1,109
  • Joined

  • Last visited

  • Days Won

    17

Posts posted by Namerow


  1. (Stating the obvious) A structure won't deflect unless it's subjected to a load.  If the centre and rear sections of the unibody are supported (axle stands under the pinch welds at the front), then everything from the firewall forward will 'droop' because of its weight (i.e. load = force of gravity).  However, there's not much weight left up front after you remove the engine/transmission, the hood and fenders, the bumper, the front suspension/steering and the front crossmember.  As a start-off guess, I'd say maybe 150 lbs, tops

    In vertical bending, each side of the front part of the unibody gets its strength from a ~ vertical panel (the inner fender) that's reinforced by an upper and a lower boxed section.  The upper box section is sometimes called the 'horn' and it's made from very thick (0.050" steel).  The lower box section (aka the 'frame rail') is also made from 0.050" steel.  The inner fender panel is the usual 0.032" (20 gauge).  Both box sections are pretty deep vertically (which is what you want for vertical stiffness).  The inner fender isn't really a 'vertical' panel, but it serves the purpose and it ties the upper and lower box sections together.

    The center part of the unibody is boxed by the firewall  (which is, in turn, helped out by the transmission mount frame that helps to reinforce the open trans tunnel area).  The front frame rails aren't needed to box the center section of the unibody (as I think you would intuitively expect), so cutting one out isn't going to cause the centre section of the unibody to twist.

    Ahead of the firewall, when you cut out the frame rail on one side you weaken that side of the front unibody structure somewhat, but the upper boxed section and the inner fender panel are still intact.  I expect they're plenty strong (see next paragraph) to support their respective shares of the weight of the front section of the unibody (150 lb?) without any any droop, remembering too that the 'cantilever' effect of the structural weight steadily diminishes the closer you get to the firewall.  The boxing of the front unibody structure at the front by the rad support frame will further serve to resist any differential droop (i.e. twist).  Let's break it down...

    I have one of ZeddFinding's replacement frame rails in my shop.  It's made from 0.062" steel and weighs 8 lb.  Let's say the upper frame rail weighs 10 lb.  Then let's say the inner fender panel adds another 10 lb.  Add 2 lb for the T/C Rod bracket.  Add 5 lb for the shock tower blister.  Add another 5 lb for the upper ledge panel.  We're up to 40 lb per side, 80 lb total.  Let's add another 15 lb for the front rad support bulkhead.  That's 95 lb.  Add another 5 lb for miscellaneous.  Hard to make the whole front structure as being much over 100 lb.  That's just 50 lb per side.  And it's distributed over a length of about 4 feet (from firewall to front of structure), so it's not like a 50-lb point load hanging off each front bumper bracket.

    When you cut out the lower frame rail on one side, the 50 lb on that side reduces by 10 lb.  So 50 lb on the intact side, 40 lb on the cut side.  10 lb difference.  Same as two 5-lb bags of sugar.  Not much of a twisting load.  If you're still worried, put an axle stand under the corner of the rad support bulkhead and shim it up to take out all the clearance. 

    If you're still feeling uncertain, put a dial indicator on the underside of the rad support on the cut side before you cut out the rail and measure the droop after the rail comes out.  If you don't like what you see, use the axle stand and shims to push things back up into a zero-droop state before you weld in the new rail.  If you do this, I'll be curious to learn what you measure.  My guess is 4 or 5 thousandths of an inch (but I'm ready to be shown wrong).  Maybe someone else has already made this measurement?

    Everything I've said depends on your car having good structural integrity where the front unibody elements join the firewall (and, to a lesser extent, where the rad bulkhead joins the inner fenders).

    You may find the attached article, 'Analysis of Early Z Chassis' informative.  Credit to the author, James Lux.  It appeared in an old edition of a unknown club publication called 'NewZletter'.

     

    Analysis of Early Z Chassis - NewZletter - James Lux - 19xx.pdf

    • Like 2

  2. ZeddFindings (Kingston, Ontario, Canada) has been the traditional go-to supplier for Z frame rails.  Parts are well-constructed, credibly priced, and I've never heard anyone complain about fit.  Looks like your passenger-side rail is kinked...

    www.datsunzparts.com 

     


  3. Those rubber seals ('6 out of 10') respond very nicely to Krazy Glue, provided that they're just torn and all of the rubber is still there.  You can even graft in filler pieces cut from a thin sheet of rubber (arts-and-crafts store item). That said, you really have to take the handle apart to do a good repair (it's not that difficult).  I'm not aware of anyone selling replacements for these seals.

    As for a gasket material, I like the idea of cutting one from a thin sheet of clear acrylic plastic.  About the same thickness and hardness as that used in a lot of retail goods packaging.  The packaging from a windshield wiper refill might give you what you need.  If not, just cruise the aisles of a WalMart until you spot something suitable.


  4. On 10/10/2020 at 10:46 AM, CanTechZ said:

    The area that I am still looking for a solution is the connection for the front cross member.

    Check out Wheee's build thread.  He provides a nicely illustrated, step-by-step guide of how to fab this doubler plate (along with replacement of the entire frame rail, from front to rear).

    • Thanks 1

  5. 11 hours ago, grannyknot said:

    There is also these guys in Quebec, http://www.alfaparts.net/dat280.html.  They make each panel by hand, English wheel, bead roller and hammer/dolly.  They are making two rear quarter panels for my 510 right now.

     

    da5105.jpg

    I'd forgotten about Wolf Steel.  If the quality and fit are there, their S30 rear quarter looks like tremendous value.  Cdn$300 = US$225.  Looking forward to your report on the 510 quarter panels after you take delivery. 

    • Like 1

  6. Zedd Findings has always been a quality source of repro parts.  Now we have KF Vintage JDM (and I can personally vouch for both their product and their customer service).  The (important) surprise is Auto Panel Solutions from Britain.  These are previously unobtanium panels that are being delivered a hi-fi by a previously-unknown supplier.  RIP, Tabco.

    • Like 2

  7. I've painted the compartment with the engine in place, but almost everything else had been removed -- wiring harness, intake and exhaust manifolds, and most of the hard lines (only the long fuel/emissions pipes coming in from the trans tunnel remained in place).  You'll need a detailing gun to be able to work in the cramped spaces.  Certain areas can't be sprayed at the optimum angle.  Certain other areas (e.g. bottom of the hood latch bracket) are hard to get paint on at all.  You'll need to hold the gun backwards in some places (i.e. pointed toward you).  There where a few places where I began to think that an airbrush would have done a better job than the detail gun.  

    Because of the awkward spray angles, you'll get a lot of rough-surface painted areas that will need to be sanded down afterwards to achieve a decent final finish quality.  That's a lot of work.

    I can't see doing this job without removing the intake and exhaust ---  and most of the hydraulic lines.  Unfortunately, getting those lines off is something that requires a lot of care and patience.  Those tiny little 'bolts' used on the clamps are often seized.  You do not want to snap one off because there's little to zero chance you'll be able to extract the frozen-in-place remainder.  A light-duty hand-held impact driver worked well for me on these little bolts.  

    By the time you get finished, it will probably seem like it would have been a better idea to have just pulled the engine and removed the wiring harness.

    • Like 2

  8. 22 hours ago, JDMjunkies.ch said:

    And dents where there shouldn't be?

    I wonder what happened to create that big dent in the top of the upper frame?  That's thick metal up there.  must have been something pretty heavy that fell on it.

    In one of the active build threads on this site, member said he used a pneumatic 'needle-scaler' attachment to remove the old undercoating.  The results looked really good.  


  9. 2 hours ago, siteunseen said:

    I'm sure this an obvious observation to you guys BUT I'm bored so wouldn't taking the weight off the opened hatch somehow from above, straps from the ceiling maybe, make removing those Phillips head bolts much easier. I know when I've removed the hoods on my cars I used the latch for the hooking point and a ratchet strap around a beam in my garage ceiling to take that weight off. 

    Okay, back to the "Boobs" thread. :love:

     

    See photo.  Engine hoist.  Cargo straps.  Bath towels wrapped around engine hoist boom arm and hatch to protect hatch paint and glass.  With one set of cargo straps centred vertically and another centred horizontally, and using the cross-over point as the lift location, the hatch was pretty well balanced for a flat lift.  I trimmed it out by adding small weights (socket wrench sockets) as required on the hatch surface.  This wasn't so important during removal, but it was very important during re-installation in order to get the hinge bolt holes to line up.

    102_5510.JPG

    • Like 3

  10. I agree completely.  And yet, we are dealing with a shift in consumer ethics that had/has no problem with bypassing copyrights to illegally download music and movies and photos.  It seems like the transition from physical product (e.g. vinyl record) to digital product (in music, this was iterative:  cassette tape to CD to online digital) has made people decide that the product is virtual, so the ownership is virtual/meaningless too.  Complicated issue.  Early days.

    • Like 2

  11. I agree in general with your proposition.  I would replace one word: ""That's is what the scientists should be working on".  This nothing to do with scientists.  It has everything to do generational politics. 

    • If you're under 35, your premise is this:  'I have a career and and a life to pursue and I won't be held back by a virus that statistics tell me is no more dangerous to me than dying of influenza."
    • If you're older than 65, your premise is this: 'I worked hard to get where I am and now my life and my future is being jeopardized by a bunch of careless, selfish younger people who just don't care.'

     


  12. I have read the following tips about using paint strippers:

    • Results can be noticeably accelerated by laying cling-wrap over the treated areas.
    • Using the cling-wrap technique, the best of the modern-formulation automotive strippers will get the job done nicely after an overnight soak.
    • Keep the stripper application away from panel edges and seams (the stripper seeps into gaps and will re-surface later to ruin your paint job).  Keep the stripper at least 1-1/2" away from these 'porous' areas.   Use good-quality masking tape to protect them.  After your final wipe-down of the chemically-stripped zones, remove the masking tape and use sandpaper (power and manual) to remove the remaining paint.  For the aforementioned reason, the engine bay surfaces do not look like good candidates for chemical paint stripping.

  13. If possible, please mark the photo in Post #32 to show the area where the grinding needs to be done.  Based on the earlier pix (Post #28), it looks like you just ground off the weld bead that sits immediately below the perch stamping.  Is that sufficient to free up the perch?  Just want to be sure I understand this correctly.


  14. The Toronto Globe & Mail newspaper recently ran an article in which these high lumber costs were blamed on a pandemic-driven surge in home renovations.  Curiously, about a week later the same newspaper ran another article which said that a major mill on the Canadian west coast was temporarily shutting down because of an absence of demand.  I drew these apparently conflicting stories to the attention of the newspaper but never got a reply.  Thrown into this mix is the longstanding and ongoing battle between Canada and the US over the extent of protective duties imposed by the US on imported Canadian softwood lumber.  It's my sense that there's a lot of planted story-telling going on here as part of various parties' attempts to manipulate things to their benefit.

    Here in central Canada, an 8' length of 2x4 is currently selling for Cdn$6.15 (that's $6.95 tax-in).  If you're being charged 32% more than that in Atlantic Canada, it looks like a regional premium (which may depend very heavily on where your regional mills are finding their best market opportunity at the moment -- my guess being the U.S. northeast).

    SteveJ's report of US$6.00 sounds about the same as your NS pricing (converts to about Cdn $8.00, or Cdn$9.00 tax-in).

    One local lumber-department price that did catch my attention last weekend was that for a 10' strip of half-round 3/4" molding (plain, unfinished).  About Cdn$12.00 !

    • Like 1

  15. 5 hours ago, Dave WM said:

    My biggest prob right now is trying to figure out how to remove the hatch by myself.

    I'm sure others have succeeded at this task.  In my case, I used my engine hoist.  I wrapped the hatch using HF-quality cargo straps -- one strap along the vertical centreline, the other along the horizontal CL.  I used zip-ties at the crossover points so as to make sure that the straps didn't walk under load.  Lift cautiously.  Study the balance. Watch to ensure that nothing shifts.  Make sure in advance that you know where you're going to drop the hatch panel after removing it.  A set of movers' blankets is a good idea for protecting the hatch paint once in storage.

    BTW, I successfully re-installed my hatch (a much bigger challenge, BTW) using the same process in reverse.

    • Like 1

  16. On 9/5/2020 at 9:30 AM, grannyknot said:

    Will be interested to see what you think of the KlassicFab panels, they look great.

    I also have a shipment from KFVintageJDM on the way.  As per your experience, the shipment emanated from Bogota.  I, too, have found the company's customer service to be excellent -- fast replies, helpful and on-topic information.  Shipping was by way of FedEx and the costs were surprisingly modest.  I'm using a USA-to-Canada cross-border trans-shipper service recommended to me by Grannyknot and hope to take delivery at their Toronto drop site sometime next week. 

    • Like 1

  17. One potential issue that I didn't see discussed in the FrostFighter online materials:  Is the stick-on grid sufficiently thin*-yet-robust that it will tolerate occasional cleaning of the rear glass surface with glass cleaner?  That's one of the strong points of the OEM grids  --  they seem to be ok with paper-towel-and-windex cleaning from time to time. 

    (* by 'thin', I mean height above the glass surface)

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.