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CLEANING INSIDE CORNERS OF STAINLESS STEEL RECTANGULAR TRAY

We are mfrs. of stainless steel rectangular trays for sweet shop, which are in different sizes and height from 1" to 4". We cut the corners, bend the sides to 90 degree and weld it by argon welding. the outside welding marks we finish by flapwheel buffing, but the inside corner remain black as tool cannot reach their. Can somebody help me to find a way to clean the inside blackness and welding marks.

Santosh Aggarwal
STAINLESS STEEL FABRICATOR - New Delhi, Delhi, India
2005

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I hope this helps you out a little bit. I am not sure of the thickness of the buffing wheel you are using,but we have done jobs with a similar problem. Try using a buffing wheel that is not thick,and has good flexibility it will allow you to get into those corners a lot easier.

Regards,

Brian C. Gaylets
- Scranton, Pennsylvania, U.S.A.
2005

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Geometric angles require angular media or supplies.This can be done with a mass finishing systems or some kind of specially built fixturing device or reciprocating device with a hard felt or rubber bob.

AF Kenton
retired business owner - Hatboro, Pennsylvania
2005

You can use small wool felt cones, brushes with suitable polishing compounds on a high speed buffing machine with flexible shaft and a chuck. This type of machines are available with dental tools/tool-die polishing apparatus.

Peethambaram Parthasarathy
- Bangalore, India
2005

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2005

You can try pickle the weld marks using jelly like compound containing HF and HNO3. This jelly easily and quickly cleans argon weld mark on Stainless steel.

Apply the jelly with cotton ( wear rubber rubber gloves ⇦ this on eBay or Amazon [affil links] ) and let it stay for 5-10 minutes. rinse the area thoroughly with plenty of water to get bright clean finish.

Manoj Desai
- Mumbai, India

You can apply jelly type material ( to be applied with brush ) on the required area to remove welding blackishness. This is very simple application and also technically better process than any mechanical process like buffing,grinding, wire brushing etc. This is first of all mechanical process and it do not give passivation to Stainless Steel weldment area and that's why you can find yellow or red spots coming near weld seam area. These mechanical process can also affect on weld seam strength due to high pressure application. So, try using pickling jelly on SS weld seam.

Vinay Golwala
- Mumbai ( Bombay ), India
2006

You will do better to try and prevent the burning in the first place. You can do this very easily by purging the inside corner with argon gas. Use a double outlet valve from your argon regulator then fit a second flow meter with a length of argon hose and make a device to keep the argon gas on the joint. You will have no cleaning to do now.

John Taylor
- England
2006