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Anyone with a good knock-down Dob base?

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#1 woodscavenger

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Posted 30 November 2014 - 09:53 PM

My z12 is rock solid but the base is huge. I have poked around the web and have not seen much.  Any ideas out there from the meta-brain that is CloudyNights?

 

 



#2 kfiscus

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Posted 01 December 2014 - 01:45 AM

Look at my Z12 bases in the Reflector Forum's "Mega-Mods for Zhumells" thread, starting around page 16.  My design is 10 pounds lighter, easier to get through doorways, and much more durable.  An added benefit is that it won't roll around when in my van.

 

You could modify my design to make it knock-downable by using threaded inserts and bolts instead of the modified lag screws from the stock mount.

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  • 100_1642.JPG

Edited by kfiscus, 01 December 2014 - 01:47 AM.

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#3 kfiscus

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Posted 01 December 2014 - 01:50 AM

Here's a view from the rear.

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Edited by kfiscus, 01 December 2014 - 01:51 AM.

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#4 Pinbout

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Posted 01 December 2014 - 07:50 AM

My z12 is rock solid but the base is huge. I have poked around the web and have not seen much.  Any ideas out there from the meta-brain that is CloudyNights?

 

 

Astrogoods.com makes them



#5 jtsenghas

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Posted 01 December 2014 - 07:29 PM

I have an idea I'd like to draw up this week just for the fun of the exercise that may suit your needs that would be a variation of the folding base for my folding scope (in which the rocker box actually folds flat and is stored within the OTA). If you have modest woodworking skills and access to a router and a pattern bit with ball bearings on the bottom then this could be easy to make perfectly symmetrical in a single day. I recently made a replacement "stretch" version of a rocker box for a friend's Orion dob and thought afterwards I would have preferred to have made a folding version for compactness of storage. I recognize your rocker box would have to have side panels of greater stiffness due to the increased height required with smaller altitude bearings than in my case, but I have an idea that will have it latch together within seconds without any loose pieces and would probably be much lighter than the original and a tad stiffer.

 

[The following paragraphs were edited after I watched an assembly video of this scope and better understand the design of its bearings]

 

Could you share the following relevant required design information? a) the diameter and thickness of the cradles for your altitude bearings, b) your preferred height of the centers of the altitude bearing cradles during observing, c) the diameter of the bottom of your OTA, d) the height distance between the centers of your altitude bearing cradles and the top surface of your circular base for swing clearance, and e) the required width of the inside of your rocker box, that is, the distance between the near surfaces of your side boards.

 

If you want to further reduce weight you can have an open hole for your azimuth bearing similar to that of the folding triangular base on my scope, but the concept I'm willing to offer you could have a more conventional circular base with a center bushing. You could also modify your existing circular base so that your new folding sides latch onto it.

 

As soon as I compress a few photos, I'll attach those on an additional post too.  Feel welcome to PM me also on this topic, but I plan to post my drawn suggestions on this thread.

 

 

 

 


Edited by jtsenghas, 02 December 2014 - 01:03 PM.


#6 jtsenghas

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Posted 01 December 2014 - 08:05 PM

Okay, here are the photos I referenced just above. The scope still needs final varnish and paint, but the triangular base shown below, which I made two weeks ago, was the last component I needed to build so that everything could be packaged as planned. For the past five months I've used a triangular plywood box of the same dimensions as the opened base. My plan is to make an equatorial platform next that has identical Teflon pads and nylon roller bearings as this triangular base. The plan after that would be to use EITHER this folding triangular base OR the equatorial platform to place the square groundboard on.

 

My rocker box has hinged fold-out reinforcements to allow it to be very slender when packaged. The idea I propose to draw for you will be a hollow core design that will be a compromise between the original design and my set-up. This will have two vertical hinges that will allow the sides to be folded. I'm toying with a couple of ideas that won't have any loose hardware to lose in the dark. When unfolded, it would latch or bolt to a groundboard either similar to that shown, or to a more conventional round base if you really want a larger footprint and are willing to suffer the weight.

 

Attached Thumbnails

  • base folded.jpg
  • base opened.jpg
  • base with groundboard.jpg

Edited by jtsenghas, 02 December 2014 - 07:51 AM.


#7 jtsenghas

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Posted 02 December 2014 - 03:09 PM

Here's one more shot showing the leg detail. The dowels, legs, and rails are all oak because of the stresses involved. An important design element is that pair of screws through each dowel to secure each of them and to prevent the wood from splitting from the stresses of weight in use. I used pocket screws for a solid 3/8" flat-bottomed head for strength. As a last step (after this photo) I counterbored their holes 1/8" deep to keep the screw heads from scratching other surfaces.

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#8 piaras

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Posted 02 December 2014 - 06:32 PM

I made a knock down that folds up flat. Total height flat-pac is about 4" from the feet up. See this post.

Pierre


Edited by piaras, 02 December 2014 - 06:32 PM.

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#9 jtsenghas

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Posted 02 December 2014 - 07:55 PM

I like that folding base that piaras shared a link to above, and have seen a lot of good bases on these forums for dobs with low centers of gravity and large altitude bearings. I'm hoping, however, that we'll see on this thread a number of designs for closed tube scopes with high centers of gravity and small altitude bearings in which the height must be much greater than the width.

 

I've seen a lot of commercial dobs with bases of particle board that are heavier than the optical tube assembly. I've also seen a number of home-built bases for these scopes that are much too flexible. By necessity, the side boards must extend quite a bit above the front boards on these scopes, and the deflection of such cantilevered boards increases with the cube of their length. I'm thinking that, despite the increased thickness, side boards with a hollow structure would be the way to go (think of hollow interior doors and how stiff they are.) Even reusing an original circular base to simplify construction for those with more limited woodworking skills, or for those who want to save a base with digital setting circles, and making just a lightweight folding box to attach to that base could be a huge space and weight savings for the owner of a big closed-tube tube dob. I really like the designs that have no hardware to drop in the dark also. Fasteners that stay with the components, but don't interfere with their storage can be really useful, in my opinion.

 

I think it would be a fun engineering exercise for us to share some ideas on stiff, TALL, rocker boxes. I recently made a replacement base for an 8" F/6  Orion dob for a friend who is well over six feet in height. The base I made was 13" taller than the original and has a storage box in it that adds to the stiffness, but is heavier than I'd like. I purposely designed it to look much like the original, and used laminated particle board shelf stock, but could have saved half the weight if I had done something like I'm proposing here.

 

With all the experienced DIY folks on this forum, I'm willing to bet several of you can offer already-made examples. Bring it on!


Edited by jtsenghas, 02 December 2014 - 07:57 PM.


#10 Pinbout

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Posted 02 December 2014 - 08:44 PM

I made a knock down that folds up flat. Total height flat-pac is about 4" from the feet up. See this post.

Pierre

 

:waytogo:



#11 kfiscus

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Posted 02 December 2014 - 10:54 PM

My take-away from the above COOL photos provided by J.T. is the circular cutout in the base.  That's some major weight savings right there.

 

I've begun trying to imagine my non-knockdownable mounts with captive hardware, tool-free bolts and the like for people really wanting that option.  The bottom bolts holding the 3 vertical pieces would have clearance issues with their heads.



#12 jtsenghas

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Posted 03 December 2014 - 12:54 AM

Perhaps with this post I'm starting to stray a little off-topic, but I'd like to share one of my methods of keeping hardware so it won't get lost on knock-down assemblies. This is not the method I plan on using in the idea I plan to post later this week for a folding base, but I think at least a few of you out there may see how this could be useful.  This is how I keep my altitude bearing knobs from getting away.  The knobs themselves are 1/4" bolts with press-on knobs. This method allows the bolt to travel up to 1/4" less than the length of the clearance hole it passes through. 

 

First drill a clearance hole and, if desired a shallow counterbore the diameter of a fender washer. Here the hole through my altitude bearing and glued oak spacer is 13/32" and the counterbore is 1" diameter.

drill and cbore.jpg

 

Then, drill and countersink and screw on the fender washers or simply epoxy them into place.

drill washer.jpg

 

mount washer.jpg

 

(It looks like I'll have to finish this in the next post due to memory restrictions)

 

 

 

 

 



#13 jtsenghas

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Posted 03 December 2014 - 01:05 AM

(continued from above)

Now, here's the important part. Run several stainless steel nuts onto a bolt (shown are 1/4"-20) and spin them with a drill against a grinder or belt sander until their OD is just less than the clearance hole. Shown is 3/8".
grind spacers.jpg

Finally assemble your knob, washers, and glue your spacer within the assembly with epoxy or Loctite thread locker.

knob.jpg

Voila! The threaded spacer allows only a little wiggle room so threads are very easy to start when you are mating the components! The corresponding mating hole can be a threaded insert, or a nut pounded and glued into a counterbored hole on the opposite side of the mating panel, or a T-nut with the head on the opposite side.

This method is better than using retaining snap rings because the threaded spacers made from ground nuts act as a guide for assembly and they can be put on last. Just be very careful not to get glue on the threads elsewhere. I applied Loctite to the threads nearest the knob as I put it through the fender washer and then threaded the ground nut on all the way from the tip by jamming a thin screwdriver alongside it and tightening the knob.

These work great and keep all eight knobs from getting lost on my most recent scope.

Edited by jtsenghas, 03 December 2014 - 02:21 AM.


#14 jtsenghas

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Posted 03 December 2014 - 01:13 AM

My take-away from the above COOL photos provided by J.T. is the circular cutout in the base. That's some major weight savings right there.

I've begun trying to imagine my non-knockdownable mounts with captive hardware, tool-free bolts and the like for people really wanting that option. The bottom bolts holding the 3 vertical pieces would have clearance issues with their heads.

Stay tuned for a similar, but quite different method for the bottom bolts or for any members meeting at right angles! These will screw from above, but still let the panels fold flat AND the hardware will be just as captive.

Edited by jtsenghas, 03 December 2014 - 06:52 AM.


#15 kfiscus

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Posted 03 December 2014 - 10:01 PM

Clever solution.  I'm looking forward to the next installment.



#16 jtsenghas

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Posted 04 December 2014 - 09:22 AM

Within the next couple of days I plan to play in my shop and take some pictures to explain the method I'm referring to above for knock-down assembly techniques for parts meeting at right angles.  This method is easy to apply to existing assemblies of plywood or particle board that currently don't disassemble and are to be converted to break down.

 

woodscavenger, the original poster, responded to a private message last night and will reportedly try to take the relevant dimensions I requested in the near future. Again, I'm hoping this thread turns into a good discussion with many contributors on TALL, STIFF, LIGHTWEIGHT structures for dobs with relatively high centers of gravity.

 

I checked out the designs on the astrogoods.com site that Pinbout mentioned. One clever technique used there is to miter corners to 45 degrees, which can allow piano hinges to be rotated up to 270 degrees for folding.  I like that idea for some applications, but it requires greater complexity and relies even more on other threaded fasteners for strength. The method I'll propose will still let the layers fold completely flat but will have only right angle edges that are generally more within the grasp of do-it-yourselfers.

 

The design that I'm going to draw up can be simplified to have straight cuts only, allowing something similar to be made by those who have only table saws or hand-held circular saws and straight edges to clamp alongside them to use.  Construction time can be vastly reduced, profiles can be made more creatively, and precision greatly improved, however, with the use of a router with a pattern bit as shown here:

pattern bit.jpg

One nice thing about these tools is that a pattern can be retained for quickly knocking out future parts, and that pattern can be made of softer and easier to work material than the project is made from. I have a few MDF patterns carefully made for repeated use such as for the altitude bearings shown.  Another advantage is that if one part is made carefully, another can be duplicated (such as for the sides of rocker boxes) for precise assemblies. This method doesn't require additional materials for patterns.



#17 jtsenghas

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Posted 05 December 2014 - 04:27 PM

Okay, it appears that I won't have time to get to my workbench for a couple of days to mock up samples of the technique I mentioned earlier this week for attaching knock-down panels at right angles to each other, such as the sides of tall rocker boxes (that formerly were screwed from below) to be secured from above, or with securing flip-up panels to the mating sides (which is where I'll propose to use them on the upcoming suggested design). I did, however, over the last couple of days sketch it up in CAD and can show what I was referring to here. 

 

(Note: I made a minor correction in the last step of this description later in the day of this post when I realized I had made an error in the description of the final adjustment process)

 

The basis of the design is a bar knob THINNER than the panel thickness, or a knob smaller in diameter than a panel thickness, a jam nut, and a threaded rod:

 

knob photo.jpg

 

Now, before the screams of "That's nothing new! Lots of knock down assemblies use knobs and bolts or threaded rods! Even some big commercial dobs are attached to their bases with knobs on the heads of their bolts!" please hear me out.

 

The devil is in the detail of the carefully chosen dimensions and the method of setting the knob so that is captive during storage and below flush to both surfaces of the panel while stored AND while in use (which may be important for clearances or appearances). Note that in this case press-on bar knobs aren't appropriate because they can't be adjusted for angle on the final step.

 

First, get yourself the hardware shown above, so that you can take the relevant dimensions for your case. Make sure that your knob thickness and washer diameter are both less than your panel thickness. For almost all our applications I believe either 1/4"-20 or 5/16"-18 threads will do. The advantage of the 5/16" knobs is that they typically are just under the 3/4" thickness of a common panel thickness and allow for a comfortable grip if you can suffer having the larger access hole.  Of course, the 1/4"-20 bar knobs are lighter and more compact. If you use zinc plated threaded rods and don't want raw cut ends to rust, try to use only the end pieces of the rods with the plating intact and thread the cut ends into your knobs.  Many hardware stores sell short lengths of rod entirely plated, so that waste would be minimal if you used just end pieces.  Take note of the total thickness (length or height as shown) of one washer, one jam nut, and one knob. In this case that is about 1 1/4"

 

 

Choose a drill bit the nominal size of the threaded rod (which typically is a little undersized) or SCARCELY over.  You don't want clearance of more than 1/32". Drill a hole in the edge of your panel at least an inch deep for the bolt location, being very careful to make it perpendicular to the edge and centered.  If you don't have a good horizontal boring setup, drill such a hole through a narrow board of the same thickness with a drill press (if possible) and use it as a drill bushing. The importance of making this hole before the access hole through the panel is to avoid chip break-out at the knob's mounting surface.

 

Next, make a rectangular or slotted access hole in the panel at least an inch from the bottom edge with top and bottom edges parallel to that edge as shown in this next sketch.

 

dimensioned knob.PNG

 

If you rough out any holes for this access hole with hole saws, be sure to start those holes from both sides to avoid surface tear-out. For particle board you may want to make that distance to the edge greater for strength--perhaps up to 1.5". The width of the hole should be at least 1" greater than the length of the bar knob to avoid pinching fingers in use.  The height of the hole should only exceed the thickness of the knob plus washer plus nut by the amount you need your bolt to travel. If you are using threaded inserts in the mating holes that amount of bolt travel will be just under the insert's depth.  If you are using a T-nut on the opposite face, that bolt travel amount will be just under the mating panel's thickness. Shown are the dimensions I would use if the mating panel is 3/4" thick.

 

Cut your threaded rod so that fully assembled through the hole, inserted ALMOST all the way into the bar knob, and tightened with the jam nut you get your desired dimensions. You need to put the knob, washer and nut in the access hole and run your rod through the edge of your panel. Tighten that jam nut to the bar knob with an open end wrench. Take this whole assembly and tighten it with moderate hand pressure to the mating panel and note the angle the bar knob makes with the surface of the panel as shown here (in this case it is off 60 degrees): 

 

knob off-angle.PNG

 

Disassemble your panels, and sand or file a bit of material from either the bottom of the knob or the bottom of your access hole so that a subsequent assembly fits flat like this:

 

knob tight.PNG

 

Voila! You are done!  Note that the final adjustment of height will be tiny, less than a half turn of the thread, which is 0.025" for a 1/4"-20 thread, and 0.028" for the 5/16"-18 thread. In this case shown, only one sixth of a turn, or about 0.009" needed to be removed. If, over time, your panels compress a little you can repeat that last step to align your knob. Not only do flush knobs look better, they won't snag on people or equipment while in use.

 

Note the importance of keeping the height of that access hole to a minimum.  That, along with the minimal clearance of the drilled hole for the threaded rod keeps your hardware captive.  In storage it can be tucked inside like this:

 

knob stored.PNG

 

As a final note, I want to make clear that screwed assemblies are a lot stronger when the stresses on fasteners are not into the edges of plywood or particle board panels or into end grains of solid boards.  This is particularly important on tall assemblies where leverage can increase stresses on joints.  If wood screws are used into the edges of such boards they should be chosen as long as possible to avoid splitting the panels or stripping out. If I ever put screws into the edges of particle board (such as from below on the sides of a non-knockdownable rocker box) I use screws with very large heads and lengths of at least 2 1/2" such as those designed for hanging kitchen cabinets.  Similarly, threaded inserts put into edges of plywood or particle board are inherently weak.

 

T-nuts that take advantage of the full thickness of panels can be extremely strong and the method shown above can allow for easy disassembly.

 

This isn't rocket science, and I'm not claiming it represents anything very unusual or brilliant, but the devil is indeed in the detail!


Edited by jtsenghas, 06 December 2014 - 12:50 AM.


#18 kfiscus

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Posted 05 December 2014 - 04:50 PM

I like,  A LOT! :bow:



#19 jtsenghas

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Posted 06 December 2014 - 12:03 PM

Some CAD doodles regarding hollow core, lightweight tall rocker boxes:

 

In the case of woodscavenger's requirements for a Z-12 rocker box I suspect that hollow core panels would not be required for all three vertical panels because of the modest height of the front panel. I also think that knobs installed within the panels as shown in my previous post to this one would only be required in the rear flip-up panel, which may be only slightly taller than the one I showed earlier in the post of the photo of my bottom board on the triangular base. If the front panel is not a hollow core structure, that would allow for a more creative design on the front panel, such as the COOL Z12 "Z" that kfiscus shared above, although the hinge arrangement may have to be slightly different from what I'm about to share in this post. I think, however, hollow core side panels could give woodscavenger a really light stiff box on the side panels.

 

Note that for larger aperture closed-tube dobs such as a 12", as compared to 8" scopes, stiffness is MORE important for the side panels and LESS important for the front panels due to the greater difference in height between them, ESPECIALLY when small altitude bearings are used as with that Z-12.

 

Here I'll share some "CAD musings" on the general shape I have in mind.  These could have the side panels locked down as described in the previous post, but, at another time I'll show another method that will stiffen up that bottom board and simplify assembly for use with fewer fasteners.

 

The example shown further down in this post is dimensioned for an 8" F6 scope. I had the dimensions for that handy because I made a rocker box for a friend recently which could be called a "Stretch Orion XT8". That box also had folding legs to accommodate the great height of the user.

 

Here is a view of the plans of that (non-knockdownable) rocker box. The altitude bearings are 29 inches above the groundboard. That's a stiffening box with an eyepiece holder lid under the OTA:

Wren rocker.PNG

 

Shown below is a possible basic design of the same-sized box with hollow panels on the front and sides. Note that on one side the hinge would have to be offset rearward by the panel thickness to allow for everything to fold flat.  The yellow member would probably be solid pine and screwed to the front panel:

LB RR VIEW.PNG LB FRT VIEW.PNG LB FOLDED1.PNG LB FOLDED2.PNG

The views of it folded have the last panel opened 5 degrees for clarity. Piano hinges would be used on the vertical inside seams, so they would not be visible on the outside of the box. The rear board would be hinged to the base similar to that on my folding scope.  The knobs for that panel would be built into it as shown on the previous post, and would be bar knobs because that panel would be 3/4" thick.

 

On a very tall box like this I'd also want to use knobs like those discussed on the previous post near the tops of the side panels to make the corners really rigid. For thick panels like these, round 1" knobs could be used without interference. Those may not be necessary on a more modest height box such as a Z12 would require because the hinges are at thick flat edges that are in contact. Something like this could be easily stacked in the back of a closet or the bottom of a car trunk.

 

Of course, the design could be more artistically executed depending on need, capability, etc.  I'll probably post some ideas along those lines including an edge treatment that would be stylish and show no plywood edges on the hollow panels if straight lines are employed.

 

Thoughts, anyone? Constructive criticisms or alternative solutions?


Edited by jtsenghas, 06 December 2014 - 02:46 PM.


#20 woodscavenger

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Posted 07 December 2014 - 11:24 PM

The yellow bar is what I was missing in my folding models.  That could be attached very strongly with biscuits to the green board.  

 

The Z12 has a tall threaded rod/knob in the center of the rotating base.  I and see hinging the short rear green board inward having a cutout of the center tension knob in the green board allowing it to both protect the tension knob and allow other parts to lay flat on it.  

 

I love T-nuts.  Easy to work with.  Used them extensively in my truss dob.

 

Great ideas!



#21 jtsenghas

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Posted 08 December 2014 - 06:31 AM

YES, woodscavenger! Biscuit jointed edges are very strong especially when used with a good glue like Titebond II or Titebond III. I have a biscuit jointer and love how easy it makes for alignments on glue ups too. These joints handle the damp and dew well. I'm planning on using biscuits when I build my observing chair, which will be very similar to a Catsperch Pro, when I get to it (it is at least fourth on my list of astronomy projects). If you have a biscuit jointer, or access to one, I'll include that in the design.

 

Everyone else, woodscavenger and I have exchanged a few PMs and I just need a couple more dimensions from him. He has expressed compactness as a more important criterion than stiffness and, like kfiscus, would prefer his Z12 base to be as low as possible, possibly an inch shorter than the original.

 

With his preferences in mind I'm going to suggest a design that does not have hollow panels and will be essentially a knock-down version of that kfiscus design. Now that he has added a biscuit jointer to the arsenal of tools available, I'm going to suggest that yellow element above be just a 3/4" piece of the same Baltic birch plywood that the sides are made from. This design will only be marginally less stiff than that of the kfiscus design, but will have those the upper panels fold to a 2 1/4" thickness.

 

The remaining important element to work out is how the rear edges will be stiffened, as a knock-down design doesn't lend itself well to gussets like those shown on the kfiscus design. The last dimensions I'm waiting on will give me some ideas on clearances available for a short flip-up panel.

 

Whether the flip-up panel goes inward or outward may depend on how the sides are attached and the clearances involved. You'll see what I mean shortly. It will probably be so short that direction won't be a consideration for storage. It certainly won't need to be notched for the knob for wooscavenger's preferred height dimensions because the tube swing clearance required will dictate that such a panel not be tall enough to reach the center of the base if folded forward.


Edited by jtsenghas, 08 December 2014 - 09:19 AM.


#22 jtsenghas

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Posted 08 December 2014 - 11:39 AM

About using biscuits on these knock-down projects:

Biscuits are great for strength on glued panels. They have replaced dowels and floating tenons for a lot of joints in woodworking. They do, however, require a special tool for a plunge cut with a 4" diameter blade that is 5/32" thick. The biscuits themselves are either plywood or hardwood with the grain PERPENDICULAR to the edge being jointed and look like this:
biscuit1.PNG

If a knock-down box were made similar to that designed by kfiscus, but with a right-side hinge offset rearward 3/4" for folding, as shown by the vertical yellow member in my "CAD musings" above, that joint could be made like this:
biscuit2.PNG biscuit3.PNG

Shown are the dimensions of a #20 biscuit, a 3" long edge corresponding to the top left corner of the "Z", and a 3/4"x1 1/2" piece (also Baltic birch plywood) for that yellow member. The same could be done at the bottom of the same side.

Biscuits could also be used as locators in knock down assemblies if they are glued to only one panel. For example, if a 3/4" wide by 1" tall hardwood rail were screwed to each side of the round base, the sides could be engaged into biscuits glued as shown below. This assembly would be stronger and have a cleaner look if those screws had their heads on the underside of the circular base, and the outer top edges of those rails could have a large, gentle radius. This would allow the folding panels to be attached only at the flip-up rear board with two bar knobs:
biscuit4.PNG

Note a slight difference of method, as well as materials as compared to my folding scope base in the photo near the top of this thread. In my scope the three panels fold out straight for storage and are rotated 90 degrees to fit AROUND such rails. In this case, the panels are folded in thirds for storage and OPENED 90 degrees and would engage WITHIN such rails. These rails could be nearly as long as the lower edge of those side panels--I'm thinking about 14"

Such a design would require clearance to set the sides opened partially (about 60-70 degrees) onto the base, and then opened fully while engaging the exposed portions of the biscuits. It would help to sand a slight lead on the tips of the biscuits in this situation so that if the base had flexed a bit and has a tiny curve to it the biscuit slots would still easily engage. If the (short, in this case) rear flip-up panel folds OUTWARD, or rearward for storage there wouldn't be clearance issues. The only two knobs required in this case would be of the bar-knob style I described previously above and would reside in that flip-up panel. If clearances are tight, they may have to be the smaller 1/4"-20 version. T-nuts would be installed on the OUTSIDES of the side panels to match. Note that this method would also considerably stiffen that base due to the 1" tall rails and that it might be made slightly thinner than originally planned.  A third rail could also be used on the INSIDE of the front panel against the inside of the "Z", which would have two or three similar biscuit slots. That rail would have to be slightly shorter and have angled ends to allow assembly, but the rocker box could indeed be held down on all three sides this way.

Thoughts? Suggestions?.......Is there anybody out there? I was hoping for more ideas and alternatives after this thread was a week old!


Edited by jtsenghas, 08 December 2014 - 01:34 PM.


#23 Project Galileo

Project Galileo

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Posted 08 December 2014 - 02:08 PM

I made a collapsible base for my LB16.  It was a fun project.  Doweling jigs and threaded inserts made a huge difference.  It takes minutes to take down and assemble. 

 

217960_10200095361683829_1235306264_n.jp


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#24 jtsenghas

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Posted 08 December 2014 - 03:16 PM

I made a collapsible base for my LB16.  It was a fun project.  Doweling jigs and threaded inserts made a huge difference.  It takes minutes to take down and assemble. 

Very good! I know not everyone prefers hinged assemblies or need adjacent panels to fold flat on knock-down assemblies, especially when such huge components are required. I see that those arced access holes are a good ergonomic shape to put a hand into as well. Is that PVC edge banding on all those panels?



#25 Project Galileo

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Posted 08 December 2014 - 05:00 PM

The sides and edges are all laminated with a Formica laminate.  I ended up making two and selling the other.  One piece of plywood made two bases.

 

10177479_10203583582487169_1471741424321


Edited by Project Galileo, 08 December 2014 - 05:10 PM.



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