Messages

1

Toy Makers / Re: Gear Toy

« on: December 01, 2018, 03:48:19 am »

Here are the finished gear teeth cut and sanded in the blanks.


Next came drilling the holes for the cuttouts, prior to scroll sawing. I used 1/2" and 3/4" Forstner bits for the drilling, but the sanding sleeve for the 1/2" spindle sander spindle is oversized, so the smaller radiuses ended up closer to 5/8". 


And the finished scroll cut and spindle sanded cutouts. 


And with this, I am out of material for today.  Still to come for the gears is drilling out the respective peg and center pivot holes, but that may have to wait a bit. Granddaughter arrives tomorrow morning. 

Rick

2

Toy Makers / Re: Gear Toy

« on: December 01, 2018, 03:33:35 am »

I made a jig for my 4x36" belt sander table for sanding the gear and gear bases to finish size.  To minimize the amount of sanding, I did the OD sanding after cutting out the teeth.  No point in sanding wood that won't remain. 

The jig consisted of a base which had the key on the bottom for the table slot.  This key was pivoted on the left side and slotted on the right to allow adjusting its distance from the belt, the use of which will be discussed below. 


The jig had a top slider piece that had pivot holes for each size of gear and the base.  It also pivoted on the left side, on the same point as the base.  It had a pivoting slot on the right, but it was never locked down.  This pivot allowed the slider to move inward and outward so the roughed gears could be sanded progressively smaller, with the slider pivoting in until it reached the end of the slot, which acted as a stop on the sanding action. The point of that "stop" was set by locking the base distance from the belt and remained the same for all diameters of blanks. 


Pivot holes were placed such that each gear would "stop" sanding at the correct finish diameter (visible in the second photo).  The gear base is 2" OD.  The gears started at 3.375" OD and increased by two inches for the medium (5.375") and large (7.375") gears.  This jig made for very fast and accurate sanding of the ODs. 


Gear tooth profiles were sanded on a 1x30" belt sander.  The smaller size sander was required due to the narrow width of the platten, for getting in there to the bottoms of the tooth side profiles.  The bottoms had alread been cleaned up adequately using the bandsaw as described in an earlier post, but I did go in with sanding blades on the scroll saw to sand down the few spots missed by the bandsaw. 

Rick

3

Toy Makers / Re: Gear Toy

« on: December 01, 2018, 02:45:40 am »

Then came cutting the gear teeth.  For this, I used a 1/8" wide, 14tpi blade, again in the Carter Stabilizer guide.  The curves on the gears did not require use of the 1/8" blade, but making the turns inside to bottom did. 


After the tooth profiles were cut, I cleaned up the gullets using the bandsaw blade.  I held the tooth bottom in close to the blade and moved it laterally using the front surface of the blade sort of like extremely fine sandpaper to clean out the roughness left by the turns at the bottom.  Worked surprisingly well and allowed me to get nice square corners.  Before is the gullet on the left, after on the right.


Bandsaw cut gear teeth.


Rick

4

Toy Makers / Re: Gear Toy

« on: December 01, 2018, 02:35:03 am »

I cut the gear blank and gear base rough ODs on the bandsaw.  Shown is the Carter Band Saw Stabilizer I mentioned earlier for blades under 1/4" which allows effective scroll-like cutting.  It is a single, top guide, no bottom guides, which lets the blade twist a bit.  Forward tension on the blade is created by pushing the single bearing guide forward, keeping the blade securing in the groove in the bearing when backing out of cuts.  Makes if feasible to scroll cut tall pieces and stacks in surprisingly tight curves/turns. 

No tight turns with these blanks, in either the OD or cutting out the teeth.  Here I am using a 3/16" wide, 6tpi blade to cut the ODs.




Rick

5

Toy Makers / Re: Gear Toy

« on: November 30, 2018, 04:17:50 am »

...snip...
I am using my vertical mill with DRO to drill the pegboard holes rather than the printed patterns so the holes will match the PB perfectly (in theory at least).  I'm also using those holes to peg several gears in stacks. 
...snip...

My vertical mill with DRO, drilling the center holes.  Note DRO is at 0,0.   I had used a laser center-finder to line up the three peg holes and then centered the mill on the center pivot hole and zeroed the two axes, X and Y. 


And drilling the peg holes, for both the pegboard but also for locking together stacked gears.  Note the DROs show peg holes position.  The peg holes are on 1" centers since that is the hole pattern of the pegboard.  Each hole is exactly 1/2" off of the gear centerline in each axis direction, so running the DRO to 0.500" puts it right on spot. 


Here are all of the stacked and pinned gear blanks.  These were stacked in anticipation of scroll sawing, so the maximum height was 1.5".  I ended up cutting them out on my bandsaw, so stacking could have been taller, except the internal cutout of the medium and large gears required maintaining the 1.5" max.


Rick

6

Toy Makers / Re: Gear Toy

« on: November 28, 2018, 02:29:06 am »

OK guys and gals,
I posted a picture of a gear toy that I made several years ago and "A" request was made for me to show greater detail of it. 
...snip...
It is in a WOOD magazine from November 2012 issue 215! (I told you it had been a few years) 
You may have to do some research to find the magazine though. Try friends that have been in woodworking for awhile or, the library or, write or call the magazine to see if you can get a back issue from November 2012.
...snip...
You are suppose to use 1/2" MDF according to the mag but, I used plywood of course. I also made more gears than you need to but, I over do everything (and I was making two of them)
...snip...

This one really caught my interest.  I was looking for a horse pattern to make my granddaughter a birthday present and then I saw this.  Totally shifted my plans and I have started on it. 

I found the pattern article in Wood magazine using the information above, purchased and downloaded it. 

I am using MDF board as in the original plans, but this was predicated on the need to make it in a week and I had the MDF, but not 1/2" baltic birch plywood.  I had never scroll or band saw cut MDF.  It cuts fairly easy, although I suspect it is hard on blades.  I've spent the last two days figuring out how to make the gears quickly (stacking) and accurately.  I made a jig for sanding them round that has positions for each diameter of gear blank.  I am using my vertical mill with DRO to drill the pegboard holes rather than the printed patterns so the holes will match the PB perfectly (in theory at least).  I'm also using those holes to peg several gears in stacks. 

I tried using my scroll saw for cutting the tooth profiles but find it goes much faster and accurately on my band saw. I'm using a 1/8", 14 tpi blade with a Carter Band Saw Stabilizer which allows for as close to scroll saw function as I think is possible on a band saw. 

Here are my first practice pieces.  The partial large gear was done on the scroll saw. The small gear was done on the band saw.  The band saw teeth are substantially superior, in my opinion. 


With now less than a week to go, I opted to get a Lego kit for my granddaughter's birthday so I could work on the Gear Toy at a more reasonable pace and give it to her as a Christmas present. 

More later,

Rick

7

Toy Makers / Re: Gear Toy

« on: November 26, 2018, 02:51:33 pm »

OK guys and gals,
I posted a picture of a gear toy that I made several years ago and "A" request was made for me to show greater detail of it. 
...snip...

Roger,

Did you stack cut these gears?  Hard to imagine cutting them individually. 

Rick

8

General Scroll Saw Talk / Re: Blade clamps

« on: July 27, 2018, 11:05:09 pm »

I love my Scheppach deco 402....apart from the blade clamp that drives me to distraction by working loose. I have changed the Allen key bolt for a lever arm one, even cut the clamp in half so it will tighten closer, but still works loose, there must be a better way, anyone got one?

Get the Pegas blade clamp upgrade. 

If interested see my Jul. 4 reply on how to install them:
"How to install Pegas Scrollsaw Chuck head"

I have no clue if they are available for your saw, but worth finding out. 

Rick

9

General Scroll Saw Talk / Re: Pegas blade holder on Dewalt results??

« on: July 27, 2018, 11:03:05 pm »

Has anyone tried the Pegas blade holder designed for the Dewalt?  My Dewalt clamp is starting to show some bending due to torquing the clamp over the years.  Thought maybe it might be worth trying the Pegas. 

Also does anyone know if the Pegas tension screw has a 'bearing' on the tip that meets the blade, like on the Dewalt

Finally any advantage to using the Excalibur clamp with the additional tension lever?

Thanks

Larry

I've had the Pegas clamps installed on my DW788 for 3-4 weeks.  Saw seems to run and cut more smoothly.  I really like how the chuck rides on the precision sleeve same as the bearing rollers.  With the DW chucks, they ride on the threaded portion of the screw that holds it all together.  A good recipe for wobble and wear. 

Yes, the Pegas clamp has the spinning cap on the tip.  I understand from others that the DW screw fits in the Pegas chuck also. 

Rick

10

General Scroll Saw Talk / Re: How to install Pegas Scrollsaw Chuck head

« on: July 04, 2018, 01:00:06 am »

hockeyiowa,

I'll see what I can do.  I just received a set of the Pegus Heads today and installed them on my DW788 without much issue.  I was puzzled by the lack of any instructions.  The kit comes with two anodized aluminum heads, four sets of: a socket head cap screw (SHCS), precision sleeve, two washers  and a nyloc nut.  The SHCS is 3mm hex key, the nyloc nyu is 7mm, so you will need those tools to install the new heads. 

First, you'll have to figure out how to get the old heads off.  On the DW788, the SHCSs are Torx 25 drive but the nuts were 7mm, so you'll have to figure out what tool is needed to loosen your saws head screws.  I used a 7mm socket/wrench as that provided the most secure grip on the nuts. 

Once you get the screws loosen and about ready to come apart, take them apart slowly, one, to avoid dropping anything and two, to ensure you take it apart bit by bit.  Take one screw out and then the other.  As you take the second one out, the head should come loose.  On the DW7888, the arms have roller bearings through which the sleeves and screws fit.  The DW788 sleeves are not quite as wide as the arm head and neither sleeve came out when the screws/head came out, so it wasn't immediately obvious that they should come out too.  But they do need to come out in order to be replaced by the new sleeves.  I don't know what saw you have so things my be different for you with the sleeves and bearings. 

An interesting difference between the Pegas and DW788 head/sleeves is that the Pegas sleeves are longer and extend through both sides of the head flanges that fit over the arm heads.  So, you'll have to position one head hole over the arm hole and insert the sleeve through the first side of the head and through the bearing in the arm head and into the Pegas head hole on the other side. 

Then feed the SHCS/washer through that assembly, making sure the sleeve doesn't get pushed out the other side of the Pegas head.  Then put the washer/nut on to the point that the nyloc nut grabs.  In my case, the SHCSs that came with the Pegas head were quite long and so there was a lot of tightening before they started to snug up against both sides of the head.  Feed the second sleeve through the other hole.  It was tricky getting the second arm head/bearing lined up in the Pegas head so the sleeve would feed through.  Once done, put the nut and washer on and snug up. 

Once both are on and snug, you can tighten them to final position.  The SHCS head/washer and nut/washer tighten against the ends of the sleeve, leaving the head slightly loose and able to slide side to side a bit, at least in my case.  At first I thought this would be a problem, but I found that once both screws on both heads were tightened and a blade was mounted and tensioned, the side to side motion seemed to not be a problem and the heads did not shift noticeably during operation. 

Repeat the above with the second head, paying attention to get the heads oriented so the blade tightening screw/knob are on the same side. 

I did not mention anything above about head orientation, but the blade mounting area of the heads (the wider part), goes on bottom for the top head and on top for the bottom head, so the blade mounting area is toward the center on both heads. 

That is how I mounted mine. I hope this is correct, as I'd never had any scroll saw heads off previously, so I was flying by the seat of my pants.  Looks right and seems to work right. 

Good luck,

Rick

11

General Scroll Saw Talk / Troubleshooting DeWalt 788 Blade Movement

« on: June 10, 2018, 05:24:47 pm »

I have a new DeWalt 788 that I've been learning some basics on scroll sawing.  I'm exploring a blade movement issue, that of the blade moving forward and backward through the stroke.  I've determined that the blade moves forward about 1/32" from the top to near the center/just below center of the stroke and then back again the bottom of the stroke, but not as far as at the top.  Here is a video documenting that movement.  The blade is essentially traveling in an arc, which I would have thought would not be the case, given the complex mechanics and geometry of the machine design.
https://vimeo.com/274311836

In this setup, a piece of brass 1/32" wide is held in the blade clamps upon which the indicator needle is riding.

I've read the DeWalt Tune-Up material on Rick Hutchenson's site (http://www.scrollsaws.com/) but what I am seeing does not seem to be the same thing.  I believe I read somewhere early on that the DeWalt has a design "feature" of the blade moving back away from the cut on the up stroke.  But as I'm learning by trying to make tight turns and from reading that such a blade movement is not conducive to making nice tight, sharp turns, such as at sharp points in patterns.  The blade is moving forward almost the distance of the blade width (#7 Olson PGT) and back again a little over half a blade width.  I can see how that is not good for making tight, crisp turns.

Has anyone observed this motion/behavior and is there anything that can be done about it?

If there is no fix for this, I am not wed to this saw and wonder if there are other saws out there that do not have this problem.

Rick

12

Introduce Yourself. / New Guy From NE Oregon

« on: June 10, 2018, 04:38:01 pm »

Hi, Rick here, just joined after getting a DeWalt 788 so I can make puzzles for my granddaughter.  She is loving everything I do with it, even the practices pieces and the tiny pieces of scrap that come out. 

I've been a metal and wood worker for a long time, but never much considered scroll sawing.  As could be expected, there is quite a wide world in scrolling.  I've studied a lot of online stuff, watched some videos and am reading/working through some books.  The bunny puzzle was my first go at it (1/8" Baltic birch plywood), before reading or viewing much. 


Most recently, I've been exploring some issues with blade movement patterns with the 788.  I've read some online stuff on how to fix a couple know problems, but what I'm seeing doesn't seem to fit.  I'll post separately on the general forum to elaborate and seek feedback.

Rick