Small SCM slider repairs SI 16 SF

Here are some photos of the start button. I didnt realize it came apart, inexperience not enough lighting and ancient eyes. Surprised how well it all comes apart and easily. A question for you electron guys can a little blob on the contact be enough that it doesnt make contact? its shiney figured current would still pass.

Insde the panel, shortened the white, Problem not solved just got rid of the monty python piece of wire

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Inside the panel the right button is scoring saw start not working the left is the main motor. Changed at sorting out time to at least get the main motor running

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start switch removed, simple twist the part on the front panel after loosing the two slotted screws

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Before I realized I could take this apart I cut two slots on the left with a die grinder thinking I could get paper in to clean the contacts. I did with double sided auto body paper but it still didnt work. Later with some light and glasses could see it comes apart

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This broke down to about 10 little pieces but the main thing you could get at the contacts to file them. Im not sure if I have a point file maybe just found the finest one I could

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Here are two photos of the blobs I was talking about. Removed and filed the four contact surfaces. LIkely my file was too coarse.

Attachment 387728 Attachment 387729


exceded my limit oh well

and here the moving part is sort of flopping around, one more problem, thought about putting epoxy in to keep it in place so it always aligned perfectly there is still the one main spring in there

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Ended up bending that part and tried it 20 times worked perfectly. Power back on and it worked in all the testing. Im wasnt apposed to buying a new part but told not available and likely take me time to find a used one,. Its running so can take my time now to find some used parts

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you can find those on ebay. Measure the diameter of the hole. Some are NO and some are NC ( normally closed ) and some ( most ) can be wired either way. Lots of choices in start stop buttons. Dave

cant even see what I posted, have to log off to read your post Dave., Electrician said anthing lots available. Wasnt into changing it if I could repair it start button works its done id be waiting for whatever ordered and im just as well to keep it original.

Do you know on the main shut off if arcing is the main cause of failure on those, if it is then im up for taking that apart and finding the right file. Ill find back up at another time but have it working now

thanks w

here is the handle repair, I liked the idea here best of the insert with a shoulder on the back then rethread the handle if possible. Likely that didnt work but he did rethread to 3/8", I mentioned poeple dont like Tapcons, he said some people dont use them correctly then I told hiim there is not much meat here only 1/4" he said yeah he could put a nut on the back. He works on airplanes at some point I have to let people do their thing.

Hes put a washer on the one side, a tapcon inside and a nut on the back. Likely be strong and hold time will tell.


Washer on this side

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nut on the back side

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slider bearings next, got timkens with Rubber dust shields as suggested and will grease the outside as Peter suggested. Input from everyone appreciated.

also on the HP if you convert KW to HP you need your voltage. For Amps say in this case 9 amp motor how do you figure HP, Ive always figured its close to 1 Hp per amp at 600 volts, close on most of my machines that have both listed on the plated.

I looked it up other day and could not find voltage entering into it. Converting from KW it was something like 8.9 HP. Then someone had said here they are fairly tail HP. I realize there is some efficiency factor it was on one forumala at 65 percent other stuff I read said real world on these its 90 percent.

.75 kw = 1 hp approx at any voltage. the amps change with the voltage. Most SCM motors are 5.5 kw @ 50 hz or 7.5 hp @ 50hz. When the motor is run at 60hz the kw goes to 6.6 and the hp to 9. At 240v the motors draw FLA of about 20-22. Dave

thanks Dave, plate says 60 HZ, 6.6 KW and 9 amps.

more questions to follow three speeds 35 years two saws with one speed, guess it relates to blade size, splitter geez never had one of those have to take it off see it moves for 14" blade and likely 16" or maybe not. Have blades will need a rip blade for it but have a good assortment of others in two sizes likely 12 and 14"

6.6kw is just at 9hp. 9amps is probably at 440v.

9 amps 600 volts

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Not sure where to source 1000v switch gear. Lol.

I take it you are in canada?

I think so, is that bad :)

Ive done some measures on the saw, fence and top etc Ill post some of that have to do some sorting. Next thing ill look at is the riving knife. Having never used one here are some thoughts and questions. I want to know I understand it and get the best out of it it that it can do. Past experiences cabinet saw stuff not favorable.

Based on Jacks recent post the riving knife is supposed to be less than the blade kerf and thicker than the blade plate. I measured a bunch of teeth and they were different. 14" blade thicker than the 12" etc, My plate measures were .0750 Plate on a 12" blade then the 14" blade plate was .1010. I guess the reasoning for the riving knife being thicker than the blade plate is if the wood tension releases it will press on the knife and not on the blade. Never had that luxury.

I saw a photo where someone made a riving knife from an old saw blade. Seemed to make sense if the numbers work, I guess harder to machine it.

In the recent stuff posted one thing not mentioned was the position of where the riving knife sits. I can see its adjustable and this one was shimmed out. Unfortunately the table top was moved before I picked the machine up so that has to be set up. Quick glance at it and one aspect seemed odd so will take a look at that.

Riving knife on my saw is aluminum think it was .075 thick. The slots they cut in the riving knife are too large in relation to the dowel pines it fits onto. What I dont like is the knife then can be tilted back or forward or between as the slots are so large. Are your riving knives machined fairly tight so there is little play which equals little forward to back movement before you tighten it down.

Stated riving knife spacing I think ive mostly seen .6 - .8 mm. Seems pretty tight however, is there a seperate riving knife for each size saw blade? Im thinking that is a yes or do you just use a larger one for say a 12 and 14 inch blade.

Says the saw can take up to 16" but they recommend 14". Looks like it would still take a 16 with the riving knife, not this one but one made correctly. Is there such a thing as a template pattern for these riving knives?

thanks

w

I can make an outline of the knife on my SI 16. I think there is enough adjustment that it fits with both a 14 and 26" blade. When you run a slider with a scoring blade you want to standardize your blades as much as possible. I have Lee and Sharkguard make knives for me in a couple of thicknesses. It will take me a few days to get over to the saw as it is in my other building but email me and I will follow up. I use 16" blades but 14" and 16" tend to be fairly close in plate and kerf. A 12" will usually be thinner. I prefer the heavy plate larger blades so I don't use a 12" often. Dave

PS I just looked at the Sharkguard site and Lee has SCMI knives and a drawing you can look at. He supplies three thicknesses in stock. Take a look.

Thanks David

did contact him and found out there are more thicknesses than listed. I asked him if some people set them up to put pressure on the material to hold it tight to the fence and he said some people do. Seems silly if its not set up that way. A simple finishing nail nailed into a wood insert and the head cut off will preload the material and keep pressure against the fence. That makes ripping really long material easier as you walk it into the blade. I think my question about the riving knife is that you should have ones for each size of blade. Likely would have got more responses if this was a separate post. I have more questions as I set this up and will think if its better to make separate posts and Jim can combine it later.