SVP-80 Profile Knife Jig - Limiters

[alpasty]

I have just bought the above jig. All looks well made and should be great to use with the T7. After having read the manual, I couldn't see any mention of the limiters. Do these need sharpening as well to keep them the same thickness as the knife itself, or is it ok to use keep them at their original thickness as the knife slowly reduces in thickness after a few goes at sharpening?

Many thanks,

Alex

[jeffs55]

I have no direct knowledge of this jig or its use. I do not have a molding cutter. However, if there is a "limiter" made into the jig, then you should not alter its specifications. If you do, then it is only a limiter on that certain sharpening session that you are engaged in. In other words, you have destroyed its ability to limit except in that one session on the wheel. A limiter that has been altered in size, no longer limits. Its ability to limit is always changing at the whim of the person sharpening the "limiter". Having said all that, remember that I have never seen what you are asking about.

[alpasty]

Thanks for your reply, but unfortunately it seems you have not understood the question fully. European spindle moulder cutting blocks mostly have the two knives and two limiters, which are the same profile and thickness as the cutters, but blunt and slightly shorter. Their purpose is to limit the amount of wood that can be removed with each pass of the blade, making them safer to use. Chainsaw chains also have this feature to limit the amount of wood removed.

The type of cutter and block I am describing is shown below.



The steel coloured cutters are the cutters and the black ones are the limiters. So my question is that is it ok for the limiters to remain their original thickness while the cutters slowly reduce in width, or should they be reduced in width to keep them the same as the cutters?

Many thanks for any replies.

[Herman Trivilino]

Have you considered using the SVH-320 to sharpen those blades?

http://tormek.com/international/en/grinding-jigs/svh-320-planer-blade-attachment/

To answer your original question, I don't see why you'd need to do anything to those limiters unless or until they started to interfere with the cutting process by producing too much limit.

[alpasty]

The SVH-320 would possibly work for the straight cutting blades shown in the picture, the spindle moulder block will hold (and is mostly used for) profiled cutters like this for instance:



The jig I bought will handle all the different profiles I have.

I get your point about not needing to alter them unless they interfere with the cutting, I was thinking about balance or the effectiveness of the retaining wedge.

Thanks for your reply.

[jeffs55]

Thanks for your reply, but unfortunately it seems you have not understood the question fully.
You are right, I had no idea what I was talking about so I cannot help but someone on here can.

[Rob]

The SVH-320 would possibly work for the straight cutting blades shown in the picture, the spindle moulder block will hold (and is mostly used for) profiled cutters like this for instance:



The jig I bought will handle all the different profiles I have.

I get your point about not needing to alter them unless they interfere with the cutting, I was thinking about balance or the effectiveness of the retaining wedge.

Thanks for your reply.

Hi Alpasty

It appears nobody here (the Americans) have understood your question.  As I understand it, your real question is should you keep the same proportional width's of the actual cutter and the limiting cutter in your spindle moulder knives?  The answer is yes you should because the offset of the limiter knife is a safety feature of the design (it is about balance) and yes you can sharpen the limiter with your jig in much the same way as you would sharpen the actual cutting blade. 

Please forgive the Americans, they have a history of responding to perfectly innocent questions with inappropriate answers.

[alpasty]

Thanks Rob,

I was wondering, but I guess this type of spindle moulder tooling is not commonly used in America. Your answer makes sense, I guessed this would be the case. I think Tormek should perhaps update their manual to include mention of the limiters.

As an aside, when I bought the jig from Axminster at one of their tool events I asked about how many times the cutters can be resharpened and was told their thickness could be reduced by a third, and that therefore they could be resharpened at least 25 times. Reading through the manual, it clearly states that the cutter can be reduced by .3mm only, meaning 6 resharpening goes.

It still makes economical sense, but I thought I should mention it for the benefit of others, as this information seems a bit buried in the manual.

Thanks again, Alex

[Rob]

No worries :-)

[Herman Trivilino]

The jig I bought will handle all the different profiles I have.

If you'll be interchanging different blade profiles, it seems their thickness will vary.  How will you decide how thin to make the limiters? 

Or do you change out limiters when you change out blades?  If so, it may appear that Rob is right. 

[alpasty]

For each profile I have there are two blades and two appropriately shaped limiters. So each profile is basically a set of 4 pieces. I will set the jig up to sharpen a cutter and then sharpen all 4 pieces using the same setting, therefore keeping all part of the set an identical thickness.

The setting will have to be changed for each set of 4.