Jigsaw: What am I missing?

[fiatben]

Well, it's tornado season. The forecast lately has been for a nice morning followed by terrible thunderstorms in the afternoon/evening. And, of course, since it's Saturday, the storms are here all day. So, it's raining.... time to get in a little shop time.

I'm going thru my jigsaw, doing all the alignments, etc. It's pretty straight forward although a bit irritating when trying to line up the upper guide assembly, the back-up tube and the split tube while keeping the hose attached and not having the tightening of one aspect move something else. But I can persevere until it all comes together. So.... guides set, tables squared, blade tensioned, etc. But I'm missing something.... or more accurately, failing to understand how something works.

I know the blade goes up and down. And I know the lower assembly is what drives it. When I think I've got everything in place, I turn the drive shaft by hand. The bottom goes up and down, but the top doesn't move. Now obviously this isn't good because the blade just flexes up and down. I've looked thru the 8 page (1964) manual that came with it (it's an old unit, serial number SS4397 which indicates it was build in December 1978) and see nothing about locking/unlocking something, etc. The only thing I can see as a hint is that there is a spring inside the upper bracket assembly so I'm wondering if: 1. is the spring even there, and 2. is it broke, and 3. is this what makes the upper assembly go up and down and keeps tension on the blade?

Bottom line, before I go tearing it completely apart, I thought I'd seek a little guidance here. So ...... H E L P ! ? ! ? ! ?

[peterm]

Sounds like tension is not set or locked. Did you do all this :
[ATTACH]12775[/ATTACH]

[fiatben]

Thanks, Peter, for the info. I actually had a PDF of the more complete manual and printed out the pages containing your posted info. I went back out to the shop and just started over with the whole alignment/tune-up process, even removing the table to better see the stuff.

I think two things were in my way. 1. Not understanding the tensioning of the upper guide, and 2. the old thing had not been used in so long that it was sticking. When I went thru the 2nd alignment process and figured out the tensioning system, I finally got it going up and down smoothly without kinking a blade. In fact, I even did a test cut on some scrap before I was done.

My first impression; there is a learning curve to using the jigsaw. You have to be much more sensitive to the speed of the cut (how fast you feed wood) and the flexing of the blade. And I'm sure it's a real art learning how to get just the right tension on the blade. Still, I'm happy it works and see possibilities.

Now, back to my jointer......

[peterm]

Glad to see you got it working. I like the flexibility of the jigsaw, in that it can use those short stiff blades with no upper arm support and the little files. I got a few awhile ago from a local seller and used them filing a tricky opening in an aluminum thingy (technical term ) I was making. You might enjoy this post:
http://www.shopsmith.net/forums/showthr ... #post60492

[nonnac1714]

I have no air coming from the hose. Ive had everything off and cleaned and checked for blockage--- nothing hoping someone has an idea I havent tried

[JPG]

Two things to check: Nylon ball check valves and leather piston seal.

[chapmanruss]

nonnac1714,

You may find the Forum thread titled Rusty 610 Jigsaw helpful at the following link.

viewtopic.php?t=25156

It goes through replacement options of the leather piston seal plus accessing and cleaning the nylon ball check valve.

Something to keep in mind is that there were very few changes to the Jigsaw from its introduction in 1954 until it was discontinued.

[Matanuska]

Depending on your jigsaw vintage I believe you may or may not have have the internal nylon check valves & springs. The 1960's version I was given has the air puffer intake valve port blocked with a rubber plug and no nylon check valves on either the intake or discharge ports so the puffer both blows and sucks, but is still able to clear the sawdust.

plug.jpg (69.23 KiB) Viewed 2246 times

I'm guessing Magna engineers made this change after too many complaints of the original internal nylon balls with springs design clogging up (or the original owner removed them and put in the plug). My puffer performed much better after I reversed the leather cup so that it faced down rather than up, sealing on the down (puff) stroke & leaking on the upstroke, making the pump itself a simple check valve. Someone must have had it apart at some time and re-assembled it backward.

I experimented by removing the intake plug and replacing it with an external aquarium pump check valve oriented so air flow could only occur in (on the upstroke) and put a second check valve in the discharge tube to allow only blowing out (on the downstroke), but the cheap aquarium valves required too much pressure to operate and blocked off the air flow completely. I found some small spring loaded rolling ball check valves online that operate at lower differentials but didn't order them after I figured out that turning the leather cup the right direction improved the puffer performance.

I'd be interested to hear from other jigsaw owners whether their saw has nylon balls & springs or the plugged version like mine and what the serial number is. My serial number is 87859 which dates my jigsaw to the early 60's.

jigsaw serial number.jpg (75.67 KiB) Viewed 2246 times

Jig saw serial numbers.png (215.6 KiB) Viewed 2246 times

[chapmanruss]

Matanuska,

I am curious if you have had the Upper Bracket Assembly apart. Once removed from the cylinder the bracket can be separated and the check valve balls and spring can be seen.

Your Jig Saw having serial number 87859 and more importantly being Model Number 505644 would make it after the part number change in the beginning of 1964. It should be a Jig Saw made by Magna American Corporation. A look at the entire cover plate shown in your second picture of the serial number would confirm this.

[Matanuska]

Yes, I’ve driven out the pin, removed the UBA, and opened it to check & replace the gasket. The inside was empty except for the black rubber plug in the inlet hole. No nylon balls or springs.

Yes, its’s a Magna American model.

Steve