Tell Me Why This Is A Bad Idea ( If it is )

[Gregory]

There is a definite need for Zero clearance inserts for our table saws.

 

Replacements are not that expensive, and it's good to have one for different blades.

 

I've been doing this:

 

 

 

I put a strip of masking or duct tape over the opening ( over default insert with about 1/4 clearance insert underneath )..

 

Hasn't caused any problems I'm aware of.

 

Why might it be a bad idea?

 

Edited April 16, 2021 by Gregory

[thibaultron]

The tape adds little support underneath so a strip can still be pulled down and rip the tape. Others may have better reasons.

[davyboy]

Interesting,but why not make your own zero clearance inserts ? I have the Proxxon FET saw,I made my own zero clearance inserts from aluminium strip which is cheap enough. Cut to size and drill and countersink fixing screwholes,fit and slowly raise the blade. Bingo,you have an insert for every sawblade. JMO,but I think it would be a little dangerous using tape for this purpose.

 

Dave 

[Moab]

Make sure the back/far end of your fence is not closer to the blade than the front of the fence. This would increase chances for binding and kickback...Moab

[Jaager]

Your blade is up too high..  I can see that having the edge of the blade closer to vertical has fewer teeth engaged, so there is less problem with filling the gullet, but with the crown at ~1/4" clearance -using a slower feed would work and protect you better.

 

OK - armchair theory about eliminating the danger of kickback:

If there is a Pine board on top of the billet and it has a second piece of Pine glued to it at the tail end that will sit behind the billet - push it - is also sitting on the saw table and is long enough - so long that when the billet is beyond the back edge of the blade, the blade is still inside the pusher piece.

The work is hidden - so that success can only be determined post cut - but there can be no kickback and fingers are safe.

 

translation:

Pine board = any wood that is low cost and has the needed  dimensions  to keep the blade enclosed.

billet = whatever stock is being sliced up.

[Gregory]

49 minutes ago, Jaager said:

Your blade is up too high..  I

Just a random picture..

I adjust the blade based on the height of the billet being cut..

 

What do you see as a problem with the tape as a zero clearance insert?

[Gregory]

1 hour ago, Moab said:

Make sure the back/far end of your fence is not closer to the blade than the front of the fence. This would increase chances for binding and kickback...Moab

I always do..  Haven't had a problem so far with this..

 

What do you see as a problem, if any,  with the tape as a zero clearance insert?

[Gregory]

1 hour ago, davyboy said:

Interesting,but why not make your own zero clearance inserts ? I have the Proxxon FET saw,I made my own zero clearance inserts from aluminium strip which is cheap enough. Cut to size and drill and countersink fixing screwholes,fit and slowly raise the blade. Bingo,you have an insert for every sawblade. JMO,but I think it would be a little dangerous using tape for this purpose.

 

Dave 

 I did that with my Microlux.  Was easy to make with my laser..

 

But, one day I needed a new insert and thought I would try the tape as  a stop-gap before taking the time to make one,  it seemed to work OK, so I thought " Why go to the trouble to make one? "..

 

 

[Gregory]

1 hour ago, thibaultron said:

The tape adds little support underneath so a strip can still be pulled down and rip the tape. Others may have better reasons.

Haven't had that problem..   I can see where it would be more of a possibility if the blade is binding against the material.

Time to clean or replace the blade.

 

 

Will keep it in mind..

 

Edited April 16, 2021 by Gregory

[No Idea]

26 minutes ago, Gregory said:

I always do..  Haven't had a problem so far with this..

 

What do you see as a problem, if any,  with the tape as a zero clearance insert?

This is one of these solutions that seems good until things go wrong 

 

1.  You cut a thin strip of wood and the one side gets dragged down into the blade and busts through the tape seizing the saw.

2.  The tape has drag that a metal surface doesn't.  So your piece stops and your finger don't

3.  This lulls you into thinking that your saw is set up correctly 

 

I think that you have got away with things so far.  If you have worked with power tools for a long period you will know just what a nasty habit they have of biting back just when you're not expecting it.  I have so much respect for table saws that there is no way I would do this.  Just make yourself a proper zero clearance insert and have done with it.  Why even think about taking the risk.

[Jaager]

Because your tape is near wood color, I missed what you are doing.

My initial thoughts:

0}  If the tape was not uniform thickness everywhere the stock sits, the movement - up/down or wobble/rocking = bad cuts. 

But I see that the tape extends the length/width (front to back) of the table.

1}  It would be a pain to change the tape with each new thickness to meet the fence.

Then I see that the saw fence has enough slop for it to ride on top of the tape - which makes the tolerances of the machine less than impressive.

2}  If there is any friction or resistance to stock feed, it would irritate me.  If the tape has a slick surface, that should not be a problem.

 

3}  For those of us who use a Renaissance wax protective coat, stick may be a problem

 

Otherwise, what you have is an"exsert" instead of an insert that just raises the table top.  Having a junky fence makes that not a problem.

 

For a lot of things like this, corollaries to the yacht law ( I you have to ask the price, you cannot afford it.) come to mind.  In this case, if you feel the need to ask if it is a good idea, it probably is not a good idea to begin with.)

Edited April 16, 2021 by Jaager

[Gregory]

A lot to think about..

 

I appreciate the comments.

Edited April 16, 2021 by Gregory

[Gregory]

6 minutes ago, Jaager said:

Having a junky fence makes that not a problem.

Does the Byrnes saw have any vertical play when you loosen it to move it?

 

When you tighten it?

Edited April 16, 2021 by Gregory

[mtaylor]

I would think tape is a bad idea for reasons already listed.  Making a zero clearance insert out of wood or even plexi is a better idea and really not that hard.   But if tape is want you want to use, it's your fingers.    Judging from your posts here you seem insistent on the tape.

[Gregory]

21 minutes ago, mtaylor said:

Making a zero clearance insert out of wood or even plexi is a better idea and really not that hard.

I agree.  Your input is appreciated..

 

I found the tape to be quick and easy.  It didn't cause any safety concerns for me beyond what already exists.

I fail to see why my fingers would be in any more danger than with the use of a rigid insert. In either case my fingers would need to encroach on the blade, and I fail to see how a rigid insert would mitigate that if I were not being careful to keep my fingers from the path of the blade.  The tape certainly does not increase my comfort zone..

 

Now that someone mentioned it, the idea that a bind might cause a cut piece to go down through the tape, could be a gauge of a problem that needs to be addressed; cleaning, sharpening.

 

 

I'm never resistant to good ideas..  Though I try not to dismiss ideas without trying them

 

Edited April 16, 2021 by Gregory

[Bob Cleek]

On 4/16/2021 at 12:46 PM, Jaager said:

Otherwise, what you have is an"exsert" instead of an insert that just raises the table top.  Having a junky fence makes that not a problem.

My thought, too. If you have a saw that is capable of fine tolerances, e.g. a Byrnes, the tape solution will probably sacrifice some reliable accuracy.

 

On the other hand, as for tape tearing through and all that, there is an aluminium (I think) tape commonly used to tape ducting joints in HVAC installations that would probably solve any tearing issues. 

 

On balance, your idea is a clever one and perhaps a quick solution for a single cut, if you are careful and not too concerned about ultimate accuracy. For a production run of planking strips... not so much. I think you'd be better off to take the time to swap inserts rather than be sorry. Of course, it's always seems when a corner is cut for just one quick cut that's when an accident occurs. With a hand saw, "measure twice and cut once." With a table saw, "measure twice, think three times, rehearse the cut without the saw running, then cut."

Edited April 27, 2021 by Bob Cleek

[druxey]

If your brain even suggests 'Is this a bad idea?', then chances are, that it is! Use inserts for peace of mind, accuracy and bodily integrity.

[Gregory]

1 hour ago, Bob Cleek said:

if you are careful and not too concerned about ultimate accuracy.

How do you think this would affect accuracy? It raised my table by a few mills..

 

1 hour ago, druxey said:

If your brain even suggests 'Is this a bad idea?', then chances are, that it is! Use inserts for peace of mind, accuracy and bodily integrity.

Am I to believe such problems never happen with traditional ( proper ) inserts?

 

I have used this quite a bit and have had no accuracy or safety issues..

 

If one has the " proper " inserts, of course they should use them.

 

I only brought this up because I tried it on a whim, and had no issues.

 

I don't expect the pro's to stoop to such jerry rigging.     I just thought someone who is waiting on their  inserts for the Proxxon FET might give this a try  before they arrive.. ( I can't even seem to find them )

 

In hindsight, my topic title was not that well thought out..

 

 

Edited April 18, 2021 by Gregory

[Bob Cleek]

3 hours ago, Gregory said:

How do you think this would affect accuracy? It raised my table by a few mills..

The accuracy of a Byrnes Model Machines table saw is measured in thousandths of an inch with a micrometer fence adjustment. The tape may not make any difference on a right angle cut, but things can wobble when the work isn't laying perfectly flat on the table. With something between the workpiece and the table, sliding can be uneven, a slight movement can cause the blade to catch the piece and cause a kickback. It may well only happen in theory... and then again, it may happen in reality. As I said, if you wanted to take a chance, it's your blood, not mine. I think I'd be more inclined to use a larger plate and risk losing a strip down the clearance space than risk laying down tape myself. If you're looking for affirmation, yes... It shows your thinking and it's a clever work-around, but I'm not going to advise anybody to try it and be responsible if they come to grief.

[druxey]

The issue is, whether you are a pro or amateur, saw meeting flesh does not discriminate!

[Jack12477]

46 minutes ago, druxey said:

The issue is, whether you are a pro or amateur, saw meeting flesh does not discriminate!

I have a very good friend who many years ago completely lost the index and middle finger on his right hand to a table saw accident.   Ever try to pick something up with your thumb and ring finger and pinky?  Or hold a pen or pencil with a missing index and middle finger?  Think about the advice everyone is giving you ! 

Edited April 19, 2021 by Jack12477

[Roger Pellett]

Zero clearance inserts are so easy to make in your shop from thin model makers plywood that the risk of an accident from the tape idea is not worth taking.

 

When using power tools, Murphy is always just lurking in the shadows.

 

Roger

[kurtvd19]

Regarding using tape as a Zero Clearance fix.

If you have a Preac saw and are not a machinist you can't use a Zero Clearance insert due to the saw never having had one to start with.  I have at times used tape on the Preac when the stock being cut is very thin.  Stock, unmodified Preac's can cut a maximum of 1/4" due to the design of the saw.  The slot in the table top for the blade measures 0.088" wide.  The slitting blades for the Preac range from real thin up to about 0.045 - I am sure there are thicker blades that will fit but they aren't commonly used on this saw.  Most consider a 0.032" blade as towards the upper end of what they use on a Preac.

 

The first photo shows a 0.031 thick blade being used.  Note the clearance on the sides of the blade.  The second photo shows a Zero Clearance set up using painter's tape.  I think it is perfectly adequate in this case.  It does help with chip out when cutting very thin stock.  I would never use or say it's an option to use tape on a Byrnes saw or anything bigger than the Preac with it's 1/4" max cut.

 

 

[Hubac's Historian]

As long as it does the job without burning the tape, I can't see why it would be a bad idea.