docrocz
off to a rocking start
Member since June 2012
Posts: 11
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Post by docrocz on Nov 25, 2012 17:24:59 GMT -5
I've been having some great luck with using a tile saw and plugging it in to a Router Speed Control to slow down the speed of the saw to accommodate the suggested RPM's for the blade.
Now what I'd like to add to my set up is a power feed which should allow for better cut control as opposed to doing things by hand.
Does anyone have any info on building a power feed?
Any and all suggestions are welcome.
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jamesp
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Member since October 2012
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Post by jamesp on Nov 25, 2012 22:15:40 GMT -5
Covington sells their power feed seperately.It uses all thread as the lead screw.Looks like a challenging project.Maybe the gravity feed method should be considered.I have heard pros and cons on a gravity feed.Some commercial saws use it.
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Post by johnjsgems on Nov 26, 2012 20:45:49 GMT -5
Gravity would be simplest and once dialed in very good feed method. Be advised the router speed control will cut power and shorten motor life. If the motor has brushes it will work better than non brush motors but still will have negative results over time.
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Deleted
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Post by Deleted on Nov 27, 2012 15:17:09 GMT -5
Gravity would be simplest and once dialed in very good feed method. Be advised the router speed control will cut power and shorten motor life. If the motor has brushes it will work better than non brush motors but still will have negative results over time. Hi John, I am curious as to why this is. Do you know why this happens? Thanks!
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Post by johnjsgems on Nov 27, 2012 20:55:43 GMT -5
Non brush motors will die quickly because the speed controls reduce voltage to the motor. Brush type motors will run. Barranca had Sankho that made their wet polishers in Japan test them with router speed controls after customers reported they worked better slower. Per the factory the power was reduced and in long run tests the motor life was shortened. Mostly motors work best at the voltage they are wound for. Better to slow speeds through pulleys.
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jamesp
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Post by jamesp on Nov 28, 2012 5:45:04 GMT -5
Why do more saws not use gravity feed?Maybe counter weights to control down force.It just seems cheaper,simpler and more reliable.Like a giant chop saw,or do you bring the rock to the blade?
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Deleted
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Post by Deleted on Nov 28, 2012 23:02:22 GMT -5
sorry jamesp, nothing to add about gravity feed. It looks like VFD is the way to go for certain types of AC motors. The motor RPM set by the frequency of the AC current. Keep the voltage steady but slow the motor with a change in frequency does a beautiful. I don't know how the router motor controllers work. But VFD speed controllers seem a little expensive though. Might be cheaper to replace motors. editI just found pulse width modulation speed controllers for ac motors are cheap - $6 Need to check into these.
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Post by johnjsgems on Nov 29, 2012 8:45:49 GMT -5
I think most manufacturers don't make gravity feeds because most customers don't want them. Covington is only one I know of and only on their smaller slab saws. I think I've only sold one Covington gravity feed saw ever. We are a push button world and people want to turn on and not worry. Gravity feed is infinitely adjustable so in theory better than a fixed speed power feed motor. But, a fixed speed if slow works well too.
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jamesp
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Member since October 2012
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Post by jamesp on Nov 29, 2012 12:32:43 GMT -5
I agree with you John.It makes good sense.Seems self controlling in that it could speed up in thin cut and slow down in the wide cut.Unless the speed up in the thin leaves saw marks(higher in/min).If i was forced to build,i would do gravity.And you have only sold one graqvity unit?Seems odd....
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jspencer
freely admits to licking rocks
Member since March 2011
Posts: 929
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Post by jspencer on Nov 29, 2012 13:55:27 GMT -5
I added a gravity feed to my 14" saw for about $8 with materials from Home Depot. Nylon coated 3/16" cable, a couple of small rope block sheaves and an empty paint can to hold the weights. It works great and I never have saw marks on my slabs plus hardly any nibs at the end of the cut. Less nibs than most power fed saws. I put a foam rubber landing pad to ease it out of the cut when the weight hits bottom.
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Post by johnjsgems on Nov 29, 2012 20:37:59 GMT -5
Some people use a bottle or can that lowers into a larger bucket of water to "ease it at the end" to eliminate the end nub. I bought a Great Western 18" saw because it takes up about half as much space as any other 18" and because it has a fool proof gravity feed. Now if I only had time to use it. Maybe it will fly back to Quartzsite this Winter and find a new home. If I were to build a saw it would be a gravity feed if a slab saw or more likely a drop saw.
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jamesp
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Member since October 2012
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Post by jamesp on Nov 30, 2012 8:23:27 GMT -5
This conversation has been very helpful.I can build tumblers and i like my tumblers for what i do.But the saw is much more complicated.I started a saw and it is gravity feed design.I lost confidence and quit.12 inch blade,built like a chops saw.A see saw,motor on left and blade on right w/pivot in center.Belt drive on out side.Chinese blade from Daniel Lopacki(sintered). That is interesting John,that it takes up less space w/out horizontalish power feed i guess.And the idea of modification is cool-sounds like power feed sled is tugged by a weighted cableover a pulley-that's like cheating.
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Post by johnjsgems on Nov 30, 2012 10:20:58 GMT -5
They complicated it by using a really heavy weight and a hydraulic cylinder to adjust the fall rate. If the expensive cylinder failed I was thinking of using a lighter weight. I had a probably home made drop saw that had a cylinder to adjust the fall. The cylinder was bad so I "temporarily" used a bungee cord to the rafter above. Temporary lasted 5 years and was included when I sold it. The weight of the blade/arbor polled the blade down too fast without and would stall the motor.
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Post by phil on Nov 30, 2012 10:55:14 GMT -5
I have 2 saws that use a worm gear powered off a pully that's run off the same belt the motor/blade does, with a spring loaded clutch to keep tension in the belt. THe worm gear then drives a piece of allthread that drives the vice sled.....
Phil
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Post by Rockoonz on Nov 30, 2012 12:49:52 GMT -5
Wouldn't a screen door cylinder make an excellent end of cut damper? My hydraulic saw has a stop chain. It doesn't shut anything off, just stops the carriage. I think hydraulic can be the best way to go for a fast, controlled cut, but a weight feed or a screw feed are best for those who aren't into extra complications.
The only thing I truly like about a Hilquist saw is the fact that the vice is mounted backwards. With that setup the saw carriage is in roughly the same spot at the end of every cut so setting up a damper or auto shut off is easy.
Lee
Lee
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jspencer
freely admits to licking rocks
Member since March 2011
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Post by jspencer on Nov 30, 2012 23:11:50 GMT -5
Mine is an old drop type saw that was re-engineered years ago at Texas A&M University. It was used in the geology dept there. The blade no longer drops or moves side to side. It is held in place with a brace holding the blade arbor housing to the bottom steel plate. A rail and carriage system was added to the open side of the blade. The vise base moves side to side for adjusting slab thickness. I brought the cable from that base to the rear of the saw then up and over and right back to the front of the saw where it attached to a paint bucket with a 3lb. diving weight in it. I like having the weight in front instead of the backside like many I have seen made.
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jspencer
freely admits to licking rocks
Member since March 2011
Posts: 929
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Post by jspencer on Dec 5, 2012 23:47:17 GMT -5
Lee my favorite thing about the 14" Hilquist I got was the price. $140 with a like new .060 Hilquist continuous rim blade. ($300 value) Powered by a like new 3/4 HP Century motor. Been in use for about a year with no problems.
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reddogrocks
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Member since April 2012
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Post by reddogrocks on Dec 8, 2012 23:46:34 GMT -5
A variable speed controll reduces motor life cause it creates a lot of heat. I have one and when i use it everything is hot. Motors don't like to be jerked around.
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cherdarock
starting to spend too much on rocks
Member since December 2012
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Post by cherdarock on Dec 20, 2012 2:08:20 GMT -5
DOCROCZ! Tile saw? What is the blade diam? Is it like a TARGET 10" or the smaller 4"-7 1/4" size? The masonry saws that utilize the rolling table are easy to convert. What do you plan to use to hold the rock once your auto feed is in? AT any rate, I plan to post this link for goodies that make fabrication and modification more DOABLE! Click, once there, check out "Motors" heck check out everything. There is alot of wacky stuff, but I have bought a number of things from them, and they have good quality surplus items, and money back as well. GREAT resource. www.sciplus.com/category.cfm/subsection/18give some spec on the tile saw, or p.m. me if you want to make the saw do your bidding.
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bandia1
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Member since March 2020
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Post by bandia1 on Mar 11, 2020 11:52:32 GMT -5
I have been reading this thread on gravity feed with great interest, I have two 10-inch saws that I would like to add gravity feed to. Are there any pictures so I can get an idea of how to add this feature?
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