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Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 12:24 pm
by Skizzity
For me, it's a spacer.
Image
I guess next time a measurement is asked for using an unspecified method I'll just use my foot. So much attitude around.

Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 12:29 pm
by JPG
Skizzity wrote:For me, it's a spacer.
Image
I guess next time a measurement is asked for using an unspecified method I'll just use my foot. So much attitude around.

Your foot will not suffice - you ain't the king! :D

Re: RE: Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 12:34 pm
by Skizzity
JPG wrote:
Skizzity wrote:For me, it's a spacer.
Image
I guess next time a measurement is asked for using an unspecified method I'll just use my foot. So much attitude around.

Your foot will not suffice - you ain't the king! :D
I wasn't petitioning to be.....are you?

Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 1:04 pm
by reible
Some years back when I had only one shopsmith I worked on trying to get a good way of returning the headstock/blade/carriage to a previously setup condition and have it be repeatable time after time to the point of not having to worry if it was right.

Results were not good. The rubber baby bumper combined with the slop on the tube, where it hits on the headstock and the general lack of precise control led me to make several attachments to make a more positive control that I could actually adjust and return to. Success was moderate. Never to the point of being as good as I wanted.

So why do that level of control? Well one criticize of the shopsmith is fact that you have to take it from one operation to another because is all machines in one. Say you are cutting some stock and before you finish some thing comes up that you have to do some drilling..... but you know you have more identical parts you want to cut. So you take down the machine and convert it to a drill press, do the drilling and now you have to reconfigure back to your sawing operation. How nice would it be if you could get it back to the same configuration with out additional time spent on getting that set up back?

In the past I did some posts on using stop collars for some applications that related to this project. I never posted the other part which was this control issue because I was never happy with it. Besides once you have several machines this is a mute point. You simply use a second machine.

I guess what shocked me the most was now much variance there was when the rubber stop was isolated as the control. I did like 50 tests of sliding things together with that as the sole control and did measurements. If I ever find that data again I'd be willing to share it but like I said there was little consistency to the level I was hoping for. Those that have tried to use a zci can attest to that.

I see no advantage in actually getting the blade in the precise centered location in the table opening, centered is a relative term unless followed by a dimension since there will be variances between machines and blades and set up. Since we are given little guidance it is pretty much what each finds acceptable.

Ed

Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 1:37 pm
by jsburger
JPG wrote:
dusty wrote:
jsburger wrote:
We will probably never know since the person that came up with the idea is probably no longer with us. A shock absorber seems more logical since the width varies by a fair amount. However, if that is/was the intent I would think there would be two. How wide are the ones you just got? My bought new in '94 510 was 1 1/4" (I still have it). It did not center the blade. I got a new one from the MS in about '96 when I mentioned it to them. It is 1 7/16". I think JPG said his is 1 3/8".

So they are all over the place. Seems to me to be too much deviation for a spacer.

However we have to look at Magna for clues. I have an original Magna Engineering copy of the preliminary manual shipped with the first 10E's.

Page 6 talks about a spacer "bolt" for table saw mode. That to me suggests that the rubber bumper is for that same purpose. I assume the Magna made MK 5's had the bumper and it was not introduced later.

It still begs the question why the width dimension is all over the place if it is supposed to be a spacer.
I'll have to measure it again. I did but do not remember. I do know that the ones today were just a tad larger than what I already had.
I think the variance is simply the MS being sloppy.

Historically the spacer was a threaded rod(on the Greenie) that was adjustable. Unfortunately it also acted as ram rod when failing to lock the headstock prior to raising and that caused the carriage(with the hole the rod was threaded into) to become broken.

So it was eliminated with the Goldie(or about then) and the hard 3/8" spacer was added.

Then the 505-510...520 redesign took place and the spacer became a rubber tube. As for the length, the purpose is still to center the blade in the slot.(± ?) The table and carriage both contribute to the amount of length change.

My 1 3/8" one was obtained 'used' and the history is unknown(it replaces one that was shortened by becoming bowed out).

As a 'bumper' it is woefully inadequate. MHO

P.S. adjusting the table in the trunion mounting holes will shift the 'center' of the slot so there is some possible variance for dead centering. Also the ends butt against non-precision surfaces that are not even parallel to each other.
So were all the greenies Made by Magna Engineering? They had the same stop rod as the Model 10's. So can one conclude that the rubber bumper came after Magna Engineering. Possibly with Magna America or yuba in an attempt to eliminate the issue you site?

I agree the intent is not as a bumper but a spacer.

Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 3:40 pm
by robinson46176
reible wrote:Some years back when I had only one shopsmith I worked on trying to get a good way of returning the headstock/blade/carriage to a previously setup condition and have it be repeatable time after time to the point of not having to worry if it was right.

Results were not good. The rubber baby bumper combined with the slop on the tube, where it hits on the headstock and the general lack of precise control led me to make several attachments to make a more positive control that I could actually adjust and return to. Success was moderate. Never to the point of being as good as I wanted.

So why do that level of control? Well one criticize of the shopsmith is fact that you have to take it from one operation to another because is all machines in one. Say you are cutting some stock and before you finish some thing comes up that you have to do some drilling..... but you know you have more identical parts you want to cut. So you take down the machine and convert it to a drill press, do the drilling and now you have to reconfigure back to your sawing operation. How nice would it be if you could get it back to the same configuration with out additional time spent on getting that set up back?

In the past I did some posts on using stop collars for some applications that related to this project. I never posted the other part which was this control issue because I was never happy with it. Besides once you have several machines this is a mute point. You simply use a second machine.

I guess what shocked me the most was now much variance there was when the rubber stop was isolated as the control. I did like 50 tests of sliding things together with that as the sole control and did measurements. If I ever find that data again I'd be willing to share it but like I said there was little consistency to the level I was hoping for. Those that have tried to use a zci can attest to that.

I see no advantage in actually getting the blade in the precise centered location in the table opening, centered is a relative term unless followed by a dimension since there will be variances between machines and blades and set up. Since we are given little guidance it is pretty much what each finds acceptable.

Ed


I really like having a number of SS's and several other saws and being able to make a setup and and leaving it intact until I no longer need it. It works really well... but then again I can still remember back when the entire contents of my shop would fit in a 5 gallon pickle bucket and there was no money to add to it... :rolleyes: :( :o
When I finally got my first SS, a new 510 in 1988, I felt like I had reached the big time. :) Still I often added in the use of hand tools for many of those little operations that would have otherwise called for messing up a setup. I have always glad that I was taught hand tools before machinery.
So often I see guys in tiny shops kicking out super quality work and their biggest power tool is a scroll or a router and table. :cool: Like most hobbies we are all different, we all work differently and we all have widely varying goals. As you said Ed, "it is pretty much what each finds acceptable". :)

Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 3:50 pm
by jsburger
reible wrote:Some years back when I had only one shopsmith I worked on trying to get a good way of returning the headstock/blade/carriage to a previously setup condition and have it be repeatable time after time to the point of not having to worry if it was right.

Results were not good. The rubber baby bumper combined with the slop on the tube, where it hits on the headstock and the general lack of precise control led me to make several attachments to make a more positive control that I could actually adjust and return to. Success was moderate. Never to the point of being as good as I wanted.

So why do that level of control? Well one criticize of the shopsmith is fact that you have to take it from one operation to another because is all machines in one. Say you are cutting some stock and before you finish some thing comes up that you have to do some drilling..... but you know you have more identical parts you want to cut. So you take down the machine and convert it to a drill press, do the drilling and now you have to reconfigure back to your sawing operation. How nice would it be if you could get it back to the same configuration with out additional time spent on getting that set up back?

In the past I did some posts on using stop collars for some applications that related to this project. I never posted the other part which was this control issue because I was never happy with it. Besides once you have several machines this is a mute point. You simply use a second machine.

I guess what shocked me the most was now much variance there was when the rubber stop was isolated as the control. I did like 50 tests of sliding things together with that as the sole control and did measurements. If I ever find that data again I'd be willing to share it but like I said there was little consistency to the level I was hoping for. Those that have tried to use a zci can attest to that.

I see no advantage in actually getting the blade in the precise centered location in the table opening, centered is a relative term unless followed by a dimension since there will be variances between machines and blades and set up. Since we are given little guidance it is pretty much what each finds acceptable.

Ed
I totally agree. I think the real intent was to get the blade close enough so that when the table was lowered it went into the slot and not hit the table. Without a stop that gave a rough location for the table carriage one would have to fool around looking under the table, looking down through the slot or what ever to get it lined up enough to lower the table without hitting.

Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 4:09 pm
by dusty
dgreen810 wrote:Several years ago when I upgraded from 500 to 510 they included a rubber spacer to replace the hard spacer that was on the 500. I too ran into the problem of jacking around trying to locate the saw blade in the approximate center of the insert. Didn't like the idea of adjusting it with the quill. So I cut a piece of aluminum tube to the correct length, split it one side, opened it up to slide on the way bar and closed it back up with a hose clamp. PVC would work as well. Been using it for probably 15 20 years. I have a free standing Delta drill press so rarely use the SS in drill press mode.

Don G
Perfect solution to the Carriage placement issue as long as the fixed bumper/stop is tolerable. A large majority of us, however, need more flexibility.

What I find frustration is that Shopsmith does not react toward a solution. They keep selling the spacer but the specifications on that spacer are inconsistent to say the least. I have three different versions; that is, three different sets of measurements for five (5) bumpers.

If it is a "spacer" then the dimension should be the same for all of them. Sure, you can cut your own to whatever size suites your need but it will probably be made from something like PVC. Spacer, yes - shock absorber, NO.

Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 4:11 pm
by dusty
Skizzity wrote:For me, it's a spacer.
Image
I guess next time a measurement is asked for using an unspecified method I'll just use my foot. So much attitude around.
Please, can you tell me from what document this was taken. I have never seen these instructions (well, at least I have never read them before).

Re: RE: Re: Rubber Baby Bumpers

Posted: Sun May 15, 2016 4:23 pm
by Skizzity
dusty wrote:
Skizzity wrote:For me, it's a spacer.
Image
I guess next time a measurement is asked for using an unspecified method I'll just use my foot. So much attitude around.
Please, can you tell me from what document this was taken. I have never seen these instructions (well, at least I have never read them before).
I found it under _Setting Up the Table Saw Mode_ in "Mode Setups" under my Assembly & Alignment tab. It was page C-25 for me. Mark 7, 845620 Rev. A 09/10