What's new
What's new

Replacing way wipers on Big Lathe.

I used mcmaster #6 profile wiper material when I made them for my monarch which didn't come with any wipers for cross slide. I used superglue to attach. Messy and finiky but it worked out ok
20221029_112505.jpg

20221029_112434.jpg


20221029_112410.jpg
 
Make a mold out of acrylic and cast your own, I did this for a CNC lathe that I built for a prototyping company. Get the correct material from Smooth-On.

Casting is a valuable skill that can be used on a large number of projects, whether it is copying existing parts that are no longer available or making items to your own designs. Attached is a photograph of a 3 piece mold for molding seals on a back flow check valve. The missing core to create the undercuts was made from brass to get the accurate thickness required.

mold.jpg
For scale mold is 40mm x 40mm. Detail was machined with 0.25mm ball nose cutter.
 
Who knows if it's original. The bottom of the cross-slide or saddle bottom doesn't look like it was scraped and the compound does. We do know that the machine is about to get worse if nothing is done. Most think the reason ways get scores in the ways is because dirt get in under bad wipers. I have found score in the middle of a short side under the saddle in the middle and no scores running out to the edges. If it was from crud it would be scored all the way or from one side to the middle. The reason it is scored is because of lack of lubrication. Your machines lubrication system was plugged and that's why the ways are smooth. Your lucky it hasn't scored up. I bet if you had a straight edge or a long parallel and set it on the bottom of the saddle it would pivot in the middle (hinge). Thats why you need to hire someone or do it yourself to scrape new low oil scrape marks in the ways and to lower the center 40% so it doesn't rock when moved forward and back. Remeber when it is on the bed you can't pivot the saddle as it is trapped on the V ways. That's why you have to use a scraped straight edge or a ground parallel or a granite SE or parallel.
Thanks richard. The only straight edge i have is too narrow to get a good feel. I need to het myself a proper straight edge thats at least 1" wide...
 
Even one of the narrow ones should tell you. Or if you have a parallel even if its short it will tell you something or use a surface gage and indicator running along a clearance surface under there measuring the ways. Or mount the saddle on the ways near the right TS end and put a indicator on the cross-slide flat and move it 1/2" and see if it rocks.
 
Just finished stoning the ways under the sadle... it looks better, and i think im just going to install it as is with the new oil sysytem that works.

I still have yet to buy or make a hand scraper, buy a tip, and practice before i under take scrapping . I need to use the machine, and as i said, i may use it for 2 to 3 hours a month. Always wipe the beds before use and apply vactra 2 oil...

Some pics below







 
As long as you plan on scraping them someday. I would also buy a round stone and chamfer the oil groves. If you leave them sharp the oil won't flow out of them. They will sheer the oil and it will stay in the groove. Another tip, before you move the saddle move it the opposite direction to get an oil film under the ways. Once you get around to scraping new oil pockets in the ways it will feel like it's floating on a cloud. You will have a lot of stick slip now. It's like rubbing 2 gage blocks together when the ways are like that. Remember this condition will get worse and it will score next. Be careful and good luck.
 
As long as you plan on scraping them someday. I would also buy a round stone and chamfer the oil groves. If you leave them sharp the oil won't flow out of them. They will sheer the oil and it will stay in the groove. Another tip, before you move the saddle move it the opposite direction to get an oil film under the ways. Once you get around to scraping new oil pockets in the ways it will feel like it's floating on a cloud. You will have a lot of stick slip now. It's like rubbing 2 gage blocks together when the ways are like that. Remember this condition will get worse and it will score next. Be careful and good luck.
Understood! I sent you a email for the plans of the scraper. I will definitely chamfer the oil grooves! Thanks for the advice!!
 
Better then nothing. Set one in the middle of the bottom and see if it spins in the middle. Have to teach you to step scrape. You would be better finding a longer one if you can, be it granite or cast iron. One student I has in Maryland bought a 36 x x 48 inch granite surface plate, took it to a tombstone maker and had him cut it into straight-edges. Rounded the edges and he said it worked quit well.
 








 
Back
Top